89 'Z upgrades and GEN V LT4 swap
#1
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
89 'Z upgrades and GEN V LT4 swap
Working on a project with my brother. Taking his Camaro and turning it free. It already has been a great experience, and we just got started. A little back story on the car. He bought it out of NY about 7 years ago from the second owner of the car. He had owned it for about 6 months before his lady got preggo and was told to sell it. The first owner bought it new and was a weekend car that was garage kept. About 4 years ago I was intent on buying the car from him, so I drove it in 2 days to California from Michigan. Fast forward to a few months ago and he moved in with my family. The car returned to his ownership and the project began.
The plan is to swap a GEN V LT4 into the car with a 8l90 trans. Fist thing we want to do is get the car ready for the added power by getting the suspension, chassis, rear end, and brakes done. So I scavenged the forums before we bought anything to try and gain some insight on what would be the best parts to buy. The ultimate goal of the car is to have it keep its factory appearance when its all done.
Parts list so far:
Koni- Sport Yellow Shocks
Eibach- Pro Kit springs. thought about the Sport Line, but wanted to keep the ride height up. Out here in SoCal there are a lot of steep drives and places to bottom out.
Spohn- Panhard bar and Lower Control Arms (chrome moly)- both are adjustable with the Del Sphere pivot joints.
Lower Control Arm Relocation Brackets.
Top Down Solution- 36mm Front Sway Bar, the lighter weight hollow bars. Front steering brace (Wonder bar), and their sub frame connectors.
BMR- 25mm Rear Sway Bar.
Moog- Center link and associated steering components and bushings.
Currie Enterprises- 9" rear end. 1350 Billet 28 spline yoke.
EATON Detroit TrueTrac differential
US Gears Lightning Series Ring and Pinion Gears, 3.OO
Wilwood- 14" Big Brake Kit- Using 4 piston on the rear and 6 piston up front. Also installing their Hydroboost kit
Advanti- Using their 18x9 Cammino wheels. Any wider and the fenders would have to be flared. We decided that we didn't want to mess with body work trying to get wider tires to fit. Maybe in the future that will change. But not for right now.
Nitto- NT555 G2 275/40. I think these tires will provide what the car will need. Tires are one of those things that you really don't know for sure until you run them.
Thats the end of the list so far. More to come as it heads to the body shop and the engine swap happens.
Out with the old...!
The plan is to swap a GEN V LT4 into the car with a 8l90 trans. Fist thing we want to do is get the car ready for the added power by getting the suspension, chassis, rear end, and brakes done. So I scavenged the forums before we bought anything to try and gain some insight on what would be the best parts to buy. The ultimate goal of the car is to have it keep its factory appearance when its all done.
Parts list so far:
Koni- Sport Yellow Shocks
Eibach- Pro Kit springs. thought about the Sport Line, but wanted to keep the ride height up. Out here in SoCal there are a lot of steep drives and places to bottom out.
Spohn- Panhard bar and Lower Control Arms (chrome moly)- both are adjustable with the Del Sphere pivot joints.
Lower Control Arm Relocation Brackets.
Top Down Solution- 36mm Front Sway Bar, the lighter weight hollow bars. Front steering brace (Wonder bar), and their sub frame connectors.
BMR- 25mm Rear Sway Bar.
Moog- Center link and associated steering components and bushings.
Currie Enterprises- 9" rear end. 1350 Billet 28 spline yoke.
EATON Detroit TrueTrac differential
US Gears Lightning Series Ring and Pinion Gears, 3.OO
Wilwood- 14" Big Brake Kit- Using 4 piston on the rear and 6 piston up front. Also installing their Hydroboost kit
Advanti- Using their 18x9 Cammino wheels. Any wider and the fenders would have to be flared. We decided that we didn't want to mess with body work trying to get wider tires to fit. Maybe in the future that will change. But not for right now.
Nitto- NT555 G2 275/40. I think these tires will provide what the car will need. Tires are one of those things that you really don't know for sure until you run them.
Thats the end of the list so far. More to come as it heads to the body shop and the engine swap happens.
Out with the old...!
Last edited by Robbie_S; 09-07-2017 at 01:33 PM. Reason: Part list update
#2
Supreme Member
iTrader: (15)
Re: 89 'Z upgrades and GEN V LT4 swap
Sounds like you have some serious money to throw at this car, should be fun to follow. I would return the Eibach springs and use a set of ground control weight jacks. Far better then the stock springs for performance and removal/installation. You will also gain ride height adjustability which sounds like it may be a concern of yours. I thought you guys paid such high taxes out there so the roads could stay nice and pristine?
The Eibachs are a gamble with how low or high you will end up, not worth it IMO.
You'll need to add on a set of inner and outer subframe connectors. If you can weld then you should make the outers yourself and buy the inners from Alston's. If you are going to use the supercharged LT4 putting out 650 horsepower then you will need a roll bar and door bar for a 6 point cage since that engine will move you a thirdgen pretty fast. Have the same place that welds in the subframe connectors weld in the cage.
I don't see the reason for using hydroboost on this engine? You can make an argument for 6 piston front calipers and 14" rotors if you road race, otherwise they are just eye candy.
If the car has that much power (650hp) and a six point cage and a full set of frame connectors, I wouldn't screw around with rubber or poly joints just use rod ends and solid motor mounts. Spohn sells a set of one piece solid motor mounts for an LS engine but IDK if those bolt to the newer LT engine. Again, if you can weld I would make a custom set of one piece conversion mounts (thirdgen sbc to LT) that are solid. In the old sbc world you would want to look into a motor plate for 650hp but since that engine is making that much stock you can safely use the normal mounting configuration.
I could write a couple pages on suggestions but for now I'll just stop here and say good luck.
The Eibachs are a gamble with how low or high you will end up, not worth it IMO.
You'll need to add on a set of inner and outer subframe connectors. If you can weld then you should make the outers yourself and buy the inners from Alston's. If you are going to use the supercharged LT4 putting out 650 horsepower then you will need a roll bar and door bar for a 6 point cage since that engine will move you a thirdgen pretty fast. Have the same place that welds in the subframe connectors weld in the cage.
I don't see the reason for using hydroboost on this engine? You can make an argument for 6 piston front calipers and 14" rotors if you road race, otherwise they are just eye candy.
If the car has that much power (650hp) and a six point cage and a full set of frame connectors, I wouldn't screw around with rubber or poly joints just use rod ends and solid motor mounts. Spohn sells a set of one piece solid motor mounts for an LS engine but IDK if those bolt to the newer LT engine. Again, if you can weld I would make a custom set of one piece conversion mounts (thirdgen sbc to LT) that are solid. In the old sbc world you would want to look into a motor plate for 650hp but since that engine is making that much stock you can safely use the normal mounting configuration.
I could write a couple pages on suggestions but for now I'll just stop here and say good luck.
Last edited by Tibo; 08-19-2017 at 07:46 PM.
#3
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
There are some serious rain gutters that run along intersections. I will see how the Eibachs do. If they're not fitting with what I want, I will look into the ground control jacks as an option.
I hadn't thought about inner sub frame connectors. That might be something I do. It will depend on how much body flex happens when launching.
Hopefully the LT4 motivates that car... I haven't decided if a cage is going to happen or not. I plan on doing some autocross with it at a local airport which runs a monthly event. Otherwise if it makes it to the strip, I will try and keep it out of the 9's...
About the brakes, like I said, I went with the larger brakes for autocross type events. And I would much rather have more brakes than I need. Plus with the canyon roads around me, the car will see regular, spirited, driving.
I will ALWAYS take suggestions. The reason I am doing this thread is for a few reasons. I want feed back, suggestions, and help others while having it documented. So feel free to share your thoughts!
I hadn't thought about inner sub frame connectors. That might be something I do. It will depend on how much body flex happens when launching.
Hopefully the LT4 motivates that car... I haven't decided if a cage is going to happen or not. I plan on doing some autocross with it at a local airport which runs a monthly event. Otherwise if it makes it to the strip, I will try and keep it out of the 9's...
About the brakes, like I said, I went with the larger brakes for autocross type events. And I would much rather have more brakes than I need. Plus with the canyon roads around me, the car will see regular, spirited, driving.
I will ALWAYS take suggestions. The reason I am doing this thread is for a few reasons. I want feed back, suggestions, and help others while having it documented. So feel free to share your thoughts!
#4
Supreme Member
iTrader: (15)
Re: 89 'Z upgrades and GEN V LT4 swap
When I had my car down to the body only (no doors) I could pick one of the front frame horns up and raise it up before the other side was lifted. Granted I have a convertible, these cars are flimsy and need all the help they can get. The six point cage adds some rigidity, it's not only safety you're getting. Sounds like it won't be a real drag car so you could just get some swing out bars or those cheater bars that don't really qualify it as a 6 point. You know the ones that are really low and just traverse the door at your butt level.
#5
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
I know the bars. A cage would stiffen things up a bit more. But I really don't want to alter the interior and run a cage. I still need to fit car seats and put kids in the back lol Power Tour is going to happen.
#6
Supreme Member
iTrader: (11)
Join Date: Aug 2013
Location: MICHIGAN
Posts: 4,637
Received 751 Likes
on
577 Posts
Car: 1988 Trans Am
Engine: L03
Transmission: 700R4
Axle/Gears: 10 Bolt 2.73 Open
Re: 89 'Z upgrades and GEN V LT4 swap
Sounds like an interesting build to follow. Look forward to Power Tour photos too.
#7
COTM Editor
iTrader: (22)
Join Date: Mar 2001
Posts: 9,905
Likes: 0
Received 1,855 Likes
on
1,270 Posts
Car: '89 Firebird
Engine: 7.0L
Transmission: T56
Re: 89 'Z upgrades and GEN V LT4 swap
Most people use weight jacks to dial in ride height but really the usefulness is to corner weight the car. The Ground Control pieces also have linear springs front and rear.
Trending Topics
#8
Member
Join Date: May 2014
Location: Wichita Kansas
Posts: 340
Likes: 0
Received 1 Like
on
1 Post
Car: 92 RS
Engine: LT1
Transmission: 700r4
Axle/Gears: 3.73
Re: 89 'Z upgrades and GEN V LT4 swap
It will be interesting in seeing that tranny going in there. Good luck with the build can't wait to see the finished product.
#9
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
Yeah, the housing on the trans is MUCH bigger than the stock. It will certainly require cutting. I am hoping the lower area where the radio sits won't have to be cut into also, but I have a sinking suspicion that will be the case.
#10
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
Quick update: Got the front suspension and brakes installed today. Also put in new bushings. I am going to remove the steering box and check for any cracking on the frame. I know this can be issue on these cars. It looks ok, but I really won't sleep well if I don't make 100% sure. It looks ok as it is, but I can't tell completely. So before I put the steering back together I'll check. I hope the steering and bushings will be in by the end of this weekend. Also got my TDS sub frame connectors and wonder bar in today. I think by Friday the SFC will be welded in, but I'll have to wait and see if that happens.
#11
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
So the last few days has come with some good progress, and some headaches.
If you look at the picture here, you can see the rear sway bar isn't connected. With the new Currie rear end, the back of the bar didn't clear the of the housing when it was bolted in. It pulls up tight against the housing and rubs. Not sure if some custom brackets will do the trick, or maybe finding some new hardware that is long enough.
Have the Hydroboost kit installed. Also have all the hard lines ran to the brakes. Just need to have the soft lines placed in.
The Hydroboost kit definitely frees up some room around the engine. Which will be helpful I'm sure when the new engine goes in.
Here is the rear end with the Eibach springs and brake lines.
Also replaced all the steering linkage components.
The front sway bar and wonderbar both went in nicely without any issues.
There was a slight issue with front spindle clearing, but that was sorted out, and it looks very nice and clean.
Had the tires mounted on the rims and got the back spacing figured out. The rears took a 7/8" spacer to make them set just right. I am very happy with the stance and ride height.
Here is the rear:
Here is the front:
Really the only thing left before it can be driven is to shorten the drive shaft. Then it can be driven until the engine is swapped in. I am very much looking forward to driving with all the new goods under it though. That should be enough to hold over happily until the engine swap!
If you look at the picture here, you can see the rear sway bar isn't connected. With the new Currie rear end, the back of the bar didn't clear the of the housing when it was bolted in. It pulls up tight against the housing and rubs. Not sure if some custom brackets will do the trick, or maybe finding some new hardware that is long enough.
Have the Hydroboost kit installed. Also have all the hard lines ran to the brakes. Just need to have the soft lines placed in.
The Hydroboost kit definitely frees up some room around the engine. Which will be helpful I'm sure when the new engine goes in.
Here is the rear end with the Eibach springs and brake lines.
Also replaced all the steering linkage components.
The front sway bar and wonderbar both went in nicely without any issues.
There was a slight issue with front spindle clearing, but that was sorted out, and it looks very nice and clean.
Had the tires mounted on the rims and got the back spacing figured out. The rears took a 7/8" spacer to make them set just right. I am very happy with the stance and ride height.
Here is the rear:
Here is the front:
Really the only thing left before it can be driven is to shorten the drive shaft. Then it can be driven until the engine is swapped in. I am very much looking forward to driving with all the new goods under it though. That should be enough to hold over happily until the engine swap!
#12
Supreme Member
iTrader: (15)
Re: 89 'Z upgrades and GEN V LT4 swap
#13
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
I talked with my brother who is going to cut some brackets for me. Luckily he is a programmer for water jets and CNC machines... Thanks for the heads up. I had wondered about it, but figured I'd find out fairly quickly if it was going to be an issue. But seeing how you brought it up, I assume it will be. So might as well get that over with now.
Last edited by Robbie_S; 08-25-2017 at 05:52 PM.
#14
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
As a lesson learned for anyone who is going to place a aftermarket rear end into their car. If the 3rd member is larger than factory, the only sway bar I found that fits it is from BMR, part number SB003. They have bent their tubing to clear the largest of 3rd members. UMI, Spohn, and TDS all fit over a stock rear, and maybe slightly larger. So save yourself the hassle and just order from BMR if you think it may even be a problem for you.
#15
COTM Editor
iTrader: (22)
Join Date: Mar 2001
Posts: 9,905
Likes: 0
Received 1,855 Likes
on
1,270 Posts
Car: '89 Firebird
Engine: 7.0L
Transmission: T56
Re: 89 'Z upgrades and GEN V LT4 swap
I have Suspension Techniques rear sway bar with a Strange 12 bolt. Still have room to spare when car is on ground, but sway bar just barely clears as it sweeps under the axle when lifting the rear of the car.
#16
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
In the air I am unable to mount it, I can't get it far enough towards the front of the car around the 3rd member.
#17
COTM Editor
iTrader: (22)
Join Date: Mar 2001
Posts: 9,905
Likes: 0
Received 1,855 Likes
on
1,270 Posts
Car: '89 Firebird
Engine: 7.0L
Transmission: T56
Re: 89 'Z upgrades and GEN V LT4 swap
You mount a sway bar with the car on the ground and full load on suspension. The bar rotates below axle housing when the axle droops so you don't know where the bar is going to be in that scenario.
#18
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
If it hits when the rear is lifted with no load on the suspension it's a problem for me. It shouldn't contact the 3rd member in any scenario. So even if the car is squated and it clears, I would change still change it out. I don't want to have it hit when I'm doing maintenance or whatever.
#19
COTM Editor
iTrader: (22)
Join Date: Mar 2001
Posts: 9,905
Likes: 0
Received 1,855 Likes
on
1,270 Posts
Car: '89 Firebird
Engine: 7.0L
Transmission: T56
Re: 89 'Z upgrades and GEN V LT4 swap
Try it my way and see what happens.
#21
Supreme Member
iTrader: (4)
Join Date: Sep 2010
Location: Double Bratville
Posts: 1,617
Likes: 0
Received 42 Likes
on
31 Posts
Car: '89 Formula
Engine: LS2
Transmission: 4L65E
Axle/Gears: MW 3.42 12 Bolt
Re: 89 'Z upgrades and GEN V LT4 swap
On my 12 bolt, I used bigger saddle clamps for clearance. Got them from Spohn's website. Then I decided to up my rear spring rates w/RideTech coilovers, thus I needed to drop to a 19mm bar.
The best shock tech is showing up in coilovers for the rears. Multiple choices for weight jacks up front. Go adjustable, over time acquire additional springs and bars to dial it in. If you don't go adjustable, you will be re-purchasing and guessing. With the money you're putting in, go adjustable from the get go, and have control over your spring rates and height adjustments.
I don't know how built the 9" is, they do take some money to get to their reputation. Good choice on Currie. They went through a phase where QA was poor, but they have since changed that back around and are a solid choice, IMO. They might even be under-priced until they earn their reputation back.
I want to see your exhaust clearance around that trans . You should paddle shift this!
The best shock tech is showing up in coilovers for the rears. Multiple choices for weight jacks up front. Go adjustable, over time acquire additional springs and bars to dial it in. If you don't go adjustable, you will be re-purchasing and guessing. With the money you're putting in, go adjustable from the get go, and have control over your spring rates and height adjustments.
I don't know how built the 9" is, they do take some money to get to their reputation. Good choice on Currie. They went through a phase where QA was poor, but they have since changed that back around and are a solid choice, IMO. They might even be under-priced until they earn their reputation back.
I want to see your exhaust clearance around that trans . You should paddle shift this!
#22
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
Getting a column mount kit
It is going to be fun to get the swap done. So far it has just been throwing parts on it. Nothing complicated so far, just throwing money at it. I am really looking forward to the fabrication it will take to get the powertrain installed.
It is going to be fun to get the swap done. So far it has just been throwing parts on it. Nothing complicated so far, just throwing money at it. I am really looking forward to the fabrication it will take to get the powertrain installed.
#23
Supreme Member
iTrader: (15)
Re: 89 'Z upgrades and GEN V LT4 swap
Lucky.
Although if you were welding them on you could use 3/16" plate and just drill two holes 3 or four inches apart line up the top hole with the rear end, bolt the LCA into the bottom hole and then weld in place. It's fine doing it that way so long as the rear end and body don't move a millimeter.
First right hand turn you took into traffic you would hear/feel it and be wondering what was broken or installed wrong.
Although if you were welding them on you could use 3/16" plate and just drill two holes 3 or four inches apart line up the top hole with the rear end, bolt the LCA into the bottom hole and then weld in place. It's fine doing it that way so long as the rear end and body don't move a millimeter.
First right hand turn you took into traffic you would hear/feel it and be wondering what was broken or installed wrong.
#24
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
Well, the thing that really hampers what I could get done with him is that he lives in Michigan. It makes it hard to get parts made right the first time... So I am just going to buy a set already made. For $100 it is worth just buying. The back and forth of trying to get measurements right is just too much of a PITA. But, he is doing the accessory brackets for the LT4.
#25
Supreme Member
iTrader: (15)
Re: 89 'Z upgrades and GEN V LT4 swap
Well, the thing that really hampers what I could get done with him is that he lives in Michigan. It makes it hard to get parts made right the first time... So I am just going to buy a set already made. For $100 it is worth just buying. The back and forth of trying to get measurements right is just too much of a PITA. But, he is doing the accessory brackets for the LT4.
#26
COTM Editor
iTrader: (22)
Join Date: Mar 2001
Posts: 9,905
Likes: 0
Received 1,855 Likes
on
1,270 Posts
Car: '89 Firebird
Engine: 7.0L
Transmission: T56
#27
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
If you're looking for that, I'll see if he is interested in building you set now. If he is, I'll PM you his contact info and you two can figure it out. He really loves making little custom things for people.
#28
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
A little update before the holiday weekend: Car is waiting to get the SFC welded in and the LCA relocation brackets welded in too. All the other suspension and brake components are installed along with a longer drive shaft. I am looking forward to driving it and really feeling the changes that all this will do. The car hit the ground fully for the first time this afternoon... I am relived that the wheel/tire combination look fanstastic and the Eibach springs didn't lower the car by very much. The stance looks just right for my tastes. Took two pictures of the wheels (front and rear) real quick. Will up date with some better photos once its out in the sunshine!
#30
Senior Member
Re: 89 'Z upgrades and GEN V LT4 swap
Since I'm late to the game, hopefully you haven't installed the TDS inner mount SFCs yet. If you haven't, don't. These work great with the original transmissions and exhaust systems the car came with but will be in the way of the conversion crossmember required for the transmission you are planning on using. They will also cause limited heartache with exhaust routing (but the automatic transmission will be the bigger issue with exhaust routing and ground clearance). Send these back and get a set of perimeter mount ones from UMI, Spohn, BMR, etc and use those instead. I learned this after using the TDS ones for several years with a stock engine and trans and then having to modify transmission crossmembers when we swapped to LS power.
#31
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
Good to know. They are currently tacked into place, so a return is not an option. But thanks for the heads up. Looks like a new purchase will be in the not too far future.
#32
Senior Member
Re: 89 'Z upgrades and GEN V LT4 swap
Attached is a picture of the cut I had to make in one side of the Hawks T56 crossmember to get it to fit around the passenger side of the TDS mount. I actually had to cut off part of the drivers side front mount of the TDS SFC to get that side to fit. I also used 1/8 thick steel with holes in it (zip tied to the crossmember in the pics) to space it down to help clear part of the SFC mount. It works but if you can avoid it still and switch out, it will save you some headaches.
The Holley crossmember was even worse due to how it mounts.
#33
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
I think that they TDS may be taken out. Trying to decide if the cost of 2 SFC sets would outweigh the headache of a cut into the crossmember. Thank you for the picture as well. Haven't even really done much with the car as far as fabrication, and I have already got a list of Do's and Don'ts. Hopefully the list doesn't get out of control.
#34
Supreme Member
iTrader: (4)
Join Date: Sep 2010
Location: Double Bratville
Posts: 1,617
Likes: 0
Received 42 Likes
on
31 Posts
Car: '89 Formula
Engine: LS2
Transmission: 4L65E
Axle/Gears: MW 3.42 12 Bolt
Re: 89 'Z upgrades and GEN V LT4 swap
Yup, that's why I asked about your 6L80e and exhaust fitment.
I have SW 2" headers-> 3" y-pipe -> 3.5" single out w/4L65e. Fitment is a struggle. I'm sure you can do it with the 6L80e, but it will require some out-of-the-box finesse.
My y-pipe did not fit. Sent it back to Hawk's and they sent me this pic (attached) installed in one of the cars in their shop.
The two black lines is where I had to section the pipe to get better fitment. The red line is where it was contacting the cross-member. The green dot is where I decided to modify the cross-member and attach to the frame rail horizontally using some collars through the rail. I actually have more confidence with the horizontal attachment than the vertical from the bottom, but there is no need to alter the other side. I also scalloped the frame rail a little, as well.
I have Global West SFC (outers), the BMR trac pack TA, and a 3.5" aluminum driveshaft
You can see my final fitment in this embedded pic.
I have SW 2" headers-> 3" y-pipe -> 3.5" single out w/4L65e. Fitment is a struggle. I'm sure you can do it with the 6L80e, but it will require some out-of-the-box finesse.
My y-pipe did not fit. Sent it back to Hawk's and they sent me this pic (attached) installed in one of the cars in their shop.
The two black lines is where I had to section the pipe to get better fitment. The red line is where it was contacting the cross-member. The green dot is where I decided to modify the cross-member and attach to the frame rail horizontally using some collars through the rail. I actually have more confidence with the horizontal attachment than the vertical from the bottom, but there is no need to alter the other side. I also scalloped the frame rail a little, as well.
I have Global West SFC (outers), the BMR trac pack TA, and a 3.5" aluminum driveshaft
You can see my final fitment in this embedded pic.
Last edited by TEDSgrad; 09-06-2017 at 12:56 PM.
#35
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
I am not sure how the exhaust will end up running, honestly. I can't find anyone online who has done this swap. It will be a lot of learning. Are you running long tube headers or shorties? I am thinking I will end up using short to free up some room for some small CATS and hopefully have room to stuff those in. Until the trans is mounted, I have no clue what the exhaust will look like... But it will have to work somehow.
#36
Senior Member
Re: 89 'Z upgrades and GEN V LT4 swap
I am not sure how the exhaust will end up running, honestly. I can't find anyone online who has done this swap. It will be a lot of learning. Are you running long tube headers or shorties? I am thinking I will end up using short to free up some room for some small CATS and hopefully have room to stuff those in. Until the trans is mounted, I have no clue what the exhaust will look like... But it will have to work somehow.
1. There isn't a crossover point in the engine bay like there is with a SBC. The oil pan and trans bellhousing designs prevent a crossover in the engine bay. The only option I can think of that might work is to plumb it similar to a turbo system with the exhaust going forward, merging in front of the engine, and then going back as a single pipe. You might be able to find an aftermarket pan that leaves room between the pan and k member but I've never seen one for a newer motor that does this.
2. If you have to go back on both sides and join behind the transmission, the frame rails get in the way when using an automatic transmission. 4th gen Fbodies moved the frame rails out to allow routing the exhaust down the center line to the back of the transmission. 3rd gens did a forward crossover by the k member and then went back on just the passenger side so the frame rails are closer to the center. One possible option to this is when you modify the transmission tunnel, use it as a chance to raise the entire driveline up to provide space to run the exhaust. Cats will be a fun item if the emissions testers / inspectors are picky about placement.
#37
Supreme Member
iTrader: (4)
Join Date: Sep 2010
Location: Double Bratville
Posts: 1,617
Likes: 0
Received 42 Likes
on
31 Posts
Car: '89 Formula
Engine: LS2
Transmission: 4L65E
Axle/Gears: MW 3.42 12 Bolt
Re: 89 'Z upgrades and GEN V LT4 swap
LT's.
Yeah, in Cali you are forced into E-rod manifolds (LS3), not headers; but I'm not sure with the LT4 if they have approved something, yet.
Yeah, in Cali you are forced into E-rod manifolds (LS3), not headers; but I'm not sure with the LT4 if they have approved something, yet.
#38
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
They don't make an E-ROD LT4 crate, at least that I can find anywhere. So getting creative will be the name of the game. The other issue I am learning as the motor is about to get ordered is that for some reason the 8l90 will not pair up with a dry sump oil system. I am currently trying to figure out why that is...
#39
Supreme Member
iTrader: (15)
Re: 89 'Z upgrades and GEN V LT4 swap
Fabrication is the name of the game when you start mixing aftermarket parts. IMO any aftermarket retrofit transmission cross member besides the Holley unit, is a waste of money. Those aftermarket pieces turn the stock mount into the fulcrum point, not a good idea especially if the torque arm will be mounted there. The Holley unit while pricey is the only bolt on solution as the others demand further end user strengthening.
If the inner connectors are tacked in place I also say cut them off and fabricate your own or leave them knowing you will be adding to an aftermarket trans crossmember. I did a decent job of cataloging the creation of mine but fueled soul's write up is great. If you do make your own you want to weld them to the outside of the frame rail as this would save sooo much heartache.
If the inner connectors are tacked in place I also say cut them off and fabricate your own or leave them knowing you will be adding to an aftermarket trans crossmember. I did a decent job of cataloging the creation of mine but fueled soul's write up is great. If you do make your own you want to weld them to the outside of the frame rail as this would save sooo much heartache.
#40
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
Awesome bit of knowledge, Tibo. Thank you. I have welded the SFC in and plan on making the trans crossmember work around that as I can't return them anyway. So if it ends up not working, I am only out some extra time in putting them on and taking them off. I have wrote in notebook to check out the Holly member.
#41
Senior Member
iTrader: (4)
Join Date: Apr 2004
Location: Houston, TX
Posts: 556
Received 0 Likes
on
0 Posts
Car: 1986 Z28
Engine: LT1
Transmission: T5 WC
Axle/Gears: 3.42 T2R
Re: 89 'Z upgrades and GEN V LT4 swap
I have a T56, but as they said, with the Alstons you'll need to do some work to fit with any crossmember. Here's the Alston's and Hooker crossmember modified to work together. It did result in a lower point in the sfc, so I'll have to see how much to scrapes. I'd still rather scrape a sfc than anything else.
https://www.thirdgen.org/forums/memb...ml#post6153965
https://www.thirdgen.org/forums/memb...ml#post6153965
#42
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
I have a feeling a custom crossmember will have to be made. I will be having a shop do the motor and trans install. With the lack of issue solving parts to help with the build and I don't have access to a CNC and other metal working tools I would need to fabricate, I think it is best to go this route. Luckily, I will be able to help with the install to keep my involvement in this entire build. I wish I could do this in my little garage or my friends, he has a lift, and keep this 100% home built, but I think for a lot of reasons I am not going to. I know it's not the popular option on this forum. And I like the idea of being more "Built, not bought" type car. Anyway, I am confident myself and the shop will be able to figure things out.
#43
Supreme Member
iTrader: (4)
Join Date: Sep 2010
Location: Double Bratville
Posts: 1,617
Likes: 0
Received 42 Likes
on
31 Posts
Car: '89 Formula
Engine: LS2
Transmission: 4L65E
Axle/Gears: MW 3.42 12 Bolt
Re: 89 'Z upgrades and GEN V LT4 swap
LOL - you didn't design and build the LT4 or the Camaro!
As long as you are making all the informed decisions, you can be proud.
I farmed out the harness, some of the SS exhaust welding, and the final spray on the paint.
As long as you are making all the informed decisions, you can be proud.
I farmed out the harness, some of the SS exhaust welding, and the final spray on the paint.
#44
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
I hate doing it. It isn't how I'd like to do it lol. I am sure I could do it myself if I wanted to end up spending more money to correct my mistakes. And take who knows how much longer to do it. Wiring would be done somewhere no matter what. I am the Houdini of wiring! I can make any wiring disappear in a puff a smoke!
#45
COTM Editor
iTrader: (22)
Join Date: Mar 2001
Posts: 9,905
Likes: 0
Received 1,855 Likes
on
1,270 Posts
Car: '89 Firebird
Engine: 7.0L
Transmission: T56
Re: 89 'Z upgrades and GEN V LT4 swap
I had to lose the store bought trans crossmember when the inner subframe connectors were installed. The crossmembers just aren't made with that idea in mind. Had one made by a local speed shop. Link is below for some ideas.
https://www.thirdgen.org/forums/ltx-...ml#post6149848
I used to run a short UMI torque arm (same idea as BMR TrakPak) but ground clearance was horrible because the front crossbar has to dip below exhaust. The inner subframe connectors gave me a new mount point and I took advantage of that to get back ground clearance, and had a longer torque arm fabricated to work with it (somewhere between full length and UMI/BMR length).
https://www.thirdgen.org/forums/ltx-...ml#post6149848
I used to run a short UMI torque arm (same idea as BMR TrakPak) but ground clearance was horrible because the front crossbar has to dip below exhaust. The inner subframe connectors gave me a new mount point and I took advantage of that to get back ground clearance, and had a longer torque arm fabricated to work with it (somewhere between full length and UMI/BMR length).
Last edited by QwkTrip; 09-07-2017 at 11:29 PM.
#46
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
So it looks like you bolted it to a bracket that was welded to the SFC? Looks like a simple fix. And simple is good.
#47
COTM Editor
iTrader: (22)
Join Date: Mar 2001
Posts: 9,905
Likes: 0
Received 1,855 Likes
on
1,270 Posts
Car: '89 Firebird
Engine: 7.0L
Transmission: T56
Re: 89 'Z upgrades and GEN V LT4 swap
Yes. I added another picture that clearly shows it (same link below). It doesn't take much to hold the transmission in place. It is the torque arm forward mount that needs support.
My prediction is you'll have no choice but to move the torque arm mount (shortened arm) because there isn't going to be enough real estate for transmission and exhaust, let alone a torque arm too. Heck, I don't even have room for a 3.5" driveline so I had to stay with a 3" steel driveshaft. You could lose the torque arm entirely if you use the Detroit Speed 4-link conversion.
My prediction is you'll have no choice but to move the torque arm mount (shortened arm) because there isn't going to be enough real estate for transmission and exhaust, let alone a torque arm too. Heck, I don't even have room for a 3.5" driveline so I had to stay with a 3" steel driveshaft. You could lose the torque arm entirely if you use the Detroit Speed 4-link conversion.
#48
Supreme Member
iTrader: (4)
Join Date: Sep 2010
Location: Double Bratville
Posts: 1,617
Likes: 0
Received 42 Likes
on
31 Posts
Car: '89 Formula
Engine: LS2
Transmission: 4L65E
Axle/Gears: MW 3.42 12 Bolt
Re: 89 'Z upgrades and GEN V LT4 swap
It doesn't take much to hold the transmission in place. AGREE
My prediction is you'll have no choice but to move the torque arm mount (shortened arm) because there isn't going to be enough real estate for transmission and exhaust, let alone a torque arm too. Heck, I don't even have room for a 3.5" driveline so I had to stay with a 3" steel driveshaft. You could lose the torque arm entirely if you use the Detroit Speed 4-link conversion.
TA IS JUST FINE FOR OUR CARS
My prediction is you'll have no choice but to move the torque arm mount (shortened arm) because there isn't going to be enough real estate for transmission and exhaust, let alone a torque arm too. Heck, I don't even have room for a 3.5" driveline so I had to stay with a 3" steel driveshaft. You could lose the torque arm entirely if you use the Detroit Speed 4-link conversion.
TA IS JUST FINE FOR OUR CARS
#49
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
Well, car is in to get an alignment done. I think the front wheels will get spaced out a bit farther, which well give some room to run the exhaust with catalytic converters. Hoping the new suspension will settle in nicely and drop the rear a bit more. If not, it will be lowered about 1" to make the stance look as it should. Unfortunately with the sun directly overhead, I wasn't able to get a great picture of how the rear sits.
It is heading off to the body shop at the end of next week to get some rusting taken care of. Also will be replacing all the weather striping around the doors and tops. You can see some of the tape along the rear hatch marking some rust spots.
Looking forward to getting the brakes worn in and really leaning on the car and see how all the new suspension handles.
Don't mind the lack of center caps. Hoping the custom ones I am getting will be finished up soon.
It is heading off to the body shop at the end of next week to get some rusting taken care of. Also will be replacing all the weather striping around the doors and tops. You can see some of the tape along the rear hatch marking some rust spots.
Looking forward to getting the brakes worn in and really leaning on the car and see how all the new suspension handles.
Don't mind the lack of center caps. Hoping the custom ones I am getting will be finished up soon.
Last edited by Robbie_S; 09-08-2017 at 03:48 PM.
#50
Member
Thread Starter
Join Date: Sep 2016
Location: Ventura County, CA
Posts: 124
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Iroc Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: 89 'Z upgrades and GEN V LT4 swap
My prediction is you'll have no choice but to move the torque arm mount (shortened arm) because there isn't going to be enough real estate for transmission and exhaust, let alone a torque arm too. Heck, I don't even have room for a 3.5" driveline so I had to stay with a 3" steel driveshaft. You could lose the torque arm entirely if you use the Detroit Speed 4-link conversion.
I am hoping to not use a steel driveshaft. I'll have to wait and see how everything shakes out. A lot of speculation at how it will work out. But it is making me think things through more and not rely solely on trial and error.