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LTX and LSXPutting LT1s, LS1s, and their variants into Third Gens is becoming more popular. This board is for those who are doing and have done the swaps so they can discuss all of their technical aspects including repairs, swap info, and performance upgrades.
Hey everyone after 16 years of ownership I am finally working on my IROC! I bought my 1987 IROC when I was 17. I have maintained it throughout its life and in the past few years I have done minors things to it. The most major change I've done to this point is swap out the factory 700R4 for a T5. Since then I have babied the car to a certain degree for fear of grenading that T5. I finally have the time and money to do some work so I decided to swap to a T 56 so I can beat on the car again. After almost 2 years the right donar car came along (1995 Z28 LT1/T56). basically for what I would have paid for a T56 by itself I purchased a running and driving Z28. After tons of research I have decided to put both the LT1 and T56 into the IROC. I am sure many people will balk at the idea of a LT1 swap in this day and age and tell me to do an LS1 instead. I have crunched the numbers many times and done lots of looking for an LS1 but the initial investment is too high. I know they are better engines and make more power cheaper but my LT1/T56 combo cost me less than a used LS1 T56! My long term plan over the course of the next year or so is get the LT1/T56 into the IROC then pull the LT1 and stroke it as well as add a head and cam combo. but first things first, I need to pull motors and trans out of both cars. I plan on updating this thread often with pics and problems and solutions to hopefully help anyone else going the same route as me, because so many other posts I have read have helped me and I would like to give something back. One great piece of advice I read was to start at the back of the car and work my way forward, so I sorta did. I purchased a few suspension parts from Sphon Performance to help plant the IROC because already in stock form the car doesn't let the TPI plant power to the ground. So my suspension parts should help with that. Shortly after my rebuild if I have enough money I will replace my rear end as I know it is on borrowed time the second I turn the key on the stroker motor. Any ways that's my story if you read this far I hope you will continue to follow my thread in the future. I have no formal training as a mechanic, nor did I grow in a home with a father who was working cars (other than regular oil changes in our driveway). I have always loved cars though and found them interesting and enjoyable to work on (when things go smoothly of course). My main motivation to learn to work on cars was because I got so tired of feeling like I had been ripped off and screwed over by mechanics. So I started learning how to do stuff myself and found that I enjoyed it a lot (most of the time). I am always open to learning more and new/different ways to do things so please feel free to comment, question, criticize (but don't make me feel bad on purpose, remember I am an amature) as I stumble my way though this project.
Last edited by 87iroctheo; 04-13-2015 at 09:12 AM.
For you Canadians out there check out Fast Toys Performance in Winnipeg, they were awesome to deal with saved me tons of money because they dealt with all the duties etc on my Spohn parts.
My Sphon parts to help me hook up.
Last edited by 87iroctheo; 04-13-2015 at 06:51 PM.
No I plan to get it in the car and everything working, that way I know where I sit with how much money I have for the motor. I don't want to half hass anything and have to redo in the next few years, just do it right from the start with good quality parts.
I'm in the middle of an engine swap. My advice is 1) don't put yourself on a time clock. Take your time. 2) tools. Start a collection. 3) get a FSM (Helms) for both cars. 4) have fun
Thanks for the advice guys. Timeline....what is that? Haha no seriously with a wife working shift work and a 2 and 4 year old and 3rd on the way, my timeline is non existent. Did out a few late hours in this weekend. Disconnected and removed majority of motor stuff, next time it's electrical and tranny stuff and I am ready to pull the TPI!
I am sure many people will balk at the idea of a LT1 swap in this day and age and tell me to do an LS1 instead.
No no, I have built and drag raced both engines in my old 4th gen Formula. The LT1 is an awesome platform... Don't let anyone else tell you different.
Originally Posted by 87iroctheo
After almost 2 years the right donar car came along (1995 Z28 LT1/T56). basically for what I would have paid for a T56 by itself I purchased a running and driving Z28.
It sounds like you got an awesome deal then! Play your cards right and you may be able to actually make money off of this swap and be in the green cash wise. Re-sell your 5.7 tpi engine & your T-5, plus sell the 4th gen body. It would not shock me if you made most of your money back.
That's what I did with my current LS swap; I re-sold the car I pulled the engine/trans out of... and sold off my t-5 and tpi set up... I'm almost in the green lol.
Well officially I have 2 motors and trans on the floor in my garage! I will include a order of operations I kept while removing the L98 from the IROC. I jacked up the the rear of the car and put it on ramps to allow me to pull the T5 out with the motor. Went smooth. A few things I learnt along the way that were not covered anywhere else that I read was, A) the location to hook up chains on the L98 because it would be real tough to get a bolt on the back side of that head (turns out there is a bracket back ther and I removed the ac compressor and found another bracket that threaded a bolt into as well on the front B) the bulk head harness to the right of the brake booster had a bolt tucked in between the 2 connectors, it's really hard to see unless you know it's there the harness does not like to disconnect without u removing this bolt first C) I also learnt that the motor mount will infact work off my L98, at first glance they look nothing alike (the ones from the 95 vs the 87) and they are nothing alike, however the LT1 motor has some extra holes in it, so the L98 mount will bolt right to the block no problem just now you will be using different holes than the holes the Lt1 mounts were in. I got my AC delete pulley installed on the LT1 now. I have removed all wiring harnesses from both motors and ready to tackle that next. I am really struggling with my plan for the exhaust at the moment as well. There are very few shorties left on the market (much less work) that will not hold the motor back when I build it up. I don't want to buy something temporary and then replace it down the road, so I am looking at long tube again even though they are much more work. I am looking into why people go beside the trans with it. Why not 90 them with a y pipe over to the stock location? Wouldn't this eliminate the ground clearance issues everyone has with going under the crossmember? Other things on my mind include the AC on the IROC, I am going to be looking into how I can pretty up that ugly useless black box (condenser) which takes up way too much space. I would like to go to a wrecker and try to find a car that came without ac, and see if parts can be swapped to pretty that up back there. Also on the IROC the vacuum canister down at the drivers front, I would like to get rid of it completely ( I still need to research if that's a good or bad idea). Speaking of unwanted things, I plan to delete the EGR on the LT1 (it's disconnected from previous owner anyways), along with all the air pump stuff, however as I started to hack it all out and started to wonder if this will affect the optispark venting. I noticed the venting tube connects to the intake so I assume that's a vacuum venting occurring in the opti but wonder if I pull out the air pump does that make my opti more susceptible to issues like the non vented 94's and older? I couldn't find any info in this so I might have to start a new thread and see what people think. I know many have done this delete but no one seems to mention opti issues or concerns. Anywho that's what I got so far, still having fun and learning tonnes! My wife has finished up her final exams now so I should start to be able to spend more time in the garage working on my project!
My helpers
My neighbour who came to borrow my pressure washer at the wrong time, haha.
TPI T5 up for sale, got interest I her already, maybe will sell it quicker than I would like.
Last edited by 87iroctheo; 06-01-2015 at 12:01 AM.
Front chain location, inserted longer bolt so that the hook fit better.
Rear bracket, I am not sure if all l98 have this but dam was I glad mine did, made life much easier.
Ac delete pulley from TPIS in place.
Drivers side (Left side) motor mount from L98 installed on LT1. Note the vacant mount hole in the bottom right of the pic, that's where the old mount was.
Massive difference between the mounts on the L98 and LT1. This shows the LT1 mount I removed, clearly you can see why theses don't work with the 3rd gen.
Last edited by 87iroctheo; 05-31-2015 at 11:53 PM.
What you did so far is what I thought was the easiest part. I've been on my swap for 2 years and the exhaust and wiring are still unresolved. Please say you are bagging and tagging all your bolts and hardware. I can't find my LT1 water pump bolts. I tagged everything, but can't find these bolts.
Now that your engine is out, look very carefully at the frame where the steering box is connected. I had some cracks.
Haynes doesn't have detailed enough wiring diagrams. Helms FSMs are the way to go. Your list of items to do is necessary. If you watch Stacy David's "Gears" on TV, he has a book that is used for projects like ours. You can record everything you are doing and you'll probably need it in the future. I keep saying I'll get one.
I, too, had to figure out the motor mount issue. I used most of the 3rd gen mounts and yes The brackets that mount to the block on the pass side had me stumped for a while.
My plan is to mount the drivetrain from under the car with the K-member. We'll see how that goes. Keep at it.
I got my harness finished up until it's in the car. Everything was making snes as I made it so I hope it works. I found it difficult to get going but stumbled my way to a point where it made sense wasn't that difficult to do. I made 3 vids of my harness to help someone else out in the future, at the very least you will be able to see what you need to get started, and once you have that info it's pretty straight forward. With my harness I didn't de loom any of the LT1 harness so that I could put it back in easily. Once I fire the car up and know it works the way I want it to. I will clean up my harness, by removing unnecessary stuff, cutting wires to exact lengths, and re looming the whole thing so it looks nice. I was not planning on installing the LT1 until I got a set of headers for, but after days of trying all over North America I have given up. For now I am leaving the factory manifolds and I will mcgreuber something until I pull the motor this winter to rebuild it. At which point I am going to not go with Lloyd elliot heads as they are d ports and the D ports in a 3rd gen are impossible to find anywhere. I tried to find the hedman 68469 long tubes but there are none to be found, so I started looking at hedman 68460 but 1-5/8" primaries seem to be a 50/50 if they cover the D port. Guy at Lloyd elliot told me I needed 1.75" primaries if the headers aren't d port, that instantly eliminated any shorties because I could not find a single set that was larger than 1-5/8". There is simply only 1 choice of headers on the market that work this swap anymore and they are DYno Don's. The problem I have with them is that he doesn't ship to canada so I have to purchase through top down solutions which once I add a y pipe and shipping and exchange I am In the $1200+ CAD and that is for shorties. Therefore instead of LE heads I think I will run something else with a more common port design (IE DART or AFR), which then I can run those hedman 68460 $240CAD and make a custom y pipe which should prevent the need to hang exhuast below the trans crossmember. As for installing the LT1/6speed it went quite smooth. I used a happy hooker from TPIS and installed both the motor and trans as 1 piece. It's a little sketchy putting all that weight on those tiny bolts but I succeeded without it falling off the lift. Took some effort and a ratchet strap to pull the tail shaft down enough that I could tuck it I to the tunnel, the hard part was releasing it gently without it smacking up when the strap was released. To solve this issue I used 2 straps and just snugged one up before releasing the other one, then Back and forth until it was level (keep in mind I have the rear of the car on ramps also), so the TPI T5 came out as one and the LT1 T56 went in as one. I cut the opening in the tunnel about 1 inch deep towards the rear of the car and the shifter fits nice. My Sphon crossmember and torque arm took a little influence to get in place but no biggie, the are in and holding everything together nice and solid. Dang that torque arm is heavy duty compared to the factory one, I love it! That's it for this weekend, we will see where my motivation takes me to later this week. Probably work on running the harness through out the engine bay. We'll see.
To make my harness I focused on these in order of most used to lesser
When I converted my car to standard a few years back, I think I cut the hole a little large to the front, the dust booth doesn't quite cover the whole by about 1 inch, I will have to figure something out for this later.
Sphon torque arm and T56 swap crossmember, bolted up great!
Ya don't let anyone tell you a lt1 isn't worth the time. Granted the aftermarket has a bigger selection of goodies on the ls platform. My cammed and carbed lt1 just smoked an 2011 ss.
Wow, you're just movin' along! Great progress thus far. I bought a wrecked '95 Z28 with the LT1/4L60e and pulled the engine and tranny with the goal of rebuilding them and swapping them into my '87 Monte SS. I had a hard time getting parts together...in all fairness, I was trying to get AC Delco parts instead of going to Autozone/O'Reilly. With the aftermarket support not being what it was for the LT1, I decided to go LS. Had I come across a running LT1/T-56, I would not have hesitated one second!
Put in a little time tonight. I was able to get my driveshaft installed. I ended up using the drive shaft out of my 95, just because it is newer (newer should mean improved right?). You can see how close in length the 2 shafts are, but there is definitely a difference in design. The top one is from the 87 and the bottom one from the 95. For some reason it took some persuasion to get the shaft back on, once I was 1/3 of the way it slip on nice...never had that issue before (and it was same with both shafts). Also tackled tonight was the hydraulics for the clutch. I kept my 3rd gen pedals in place. Don't even think about using the 3rd gen hydraulics as the line is too short. Infact the 4th gen is even a slight stretch to get bolted in. To change it over I had to drop steering column, to access brake booseter bolts, to remove booster so that I could get the old master cylinder out. PIA to do but much easier to set up master slave once crap out of the way. Will bolt the rest back together another night, I spent for tonight.
I was interested in the differences in driveshafts myself as I wondered about that little flywheel on the 95 driveshaft. I assume it allows you to balance the shaft. Like you, I'll use the newer one.
The reason you struggled somewhat to start the slip yoke is because they actually wear in the center. You'd think that lubricated rubber would not do that to hardened metal but it does happen. I found that out when I replaced the rear seal of my 200R4. It kept leaking after I replaced the seal! I took it to a transmission shop where they measured the yoke for wear and sure enough, they said it was too worn to make a proper seal.
They ordered a new yoke, replaced the u-joint and it hasn't leaked since.
The reason you struggled somewhat to start the slip yoke is because they actually wear in the center. You'd think that lubricated rubber would not do that to hardened metal but it does happen. I found that out when I replaced the rear seal of my 200R4. It kept leaking after I replaced the seal! I took it to a transmission shop where they measured the yoke for wear and sure enough, they said it was too worn to make a proper seal.
They ordered a new yoke, replaced the u-joint and it hasn't leaked since.
I don't follow. I understand how the rubber can wear the metal down over time, but are you not talking about the rubber of the tail shaft seal? If so, I don't follow how wear on the outside of the shaft affects the Inside of the shaft and how it slips on.
I have been jumping all over on my project and therefore getting nothing done, but hopefully in short time everything will come together and it will be ready to fire. So recently I completed my oil cooler delete. I did this because I decided to go with my 3rd gen radiator and fan setup. I did this because after setting the 4th gen in place and trying out the cover etc, I thought I was going to be happier with the factory installed rad and fan setup, besides I kept my factory fan plugs, my 3rd gen rad has maybe 1000kms on it, it bolts right in place as does the fan with no modification. The only difference between the 2 rads was the extra outlet on the 4th gen (which goes to the oil cooler). My TPI had oil cooler on it as well but the lines are integrated to other lines, not a dedicated outlet on rad. After researching oil cooler delete it was pretty unanimous that they are worth deleting. It was a very simple job also. Basically removed the oil filter, then unscrewed the threaded shaft that the filter threads onto (1-1/16" If I Recall Correctly), then the cooler housing came down, there was also a nut at the front of the block that supports the lines going to the rad, after removing the cooler assembly comes out. The filter adapter is now visible. I the. Removed the 2 bolts holding it in place because they have stud ends on them and as a result will not allow a filter to thread onto the adapter plate. I looked for bolts to replave these but anything locAl was 1" or 1.5" not 1.25". So I ended up cutting the stud part off and reinstalling the adapter plate using the original bolts. The filter threaded back on perfectly and makes a nice seal all the way around. Then up on the water pump I simply plugged the spout for the cooler with a short hose and bolt (no plugs in town). Should work for time being. I am currently waiting on some parts for my rad hoses so I can connect the 1.5" outlet on the rad to the 1.25" outlet on the pump. When get all that stuff I will talk about my rad install. Till then enjoy the pics.
This is what it looks like with cooler and adapter removed, I took pic so I would remember orientation of adapter plate (in case it mattered), turned out its impression was pretty obvious the next day when I reinstalled.
On left is what you see when you change your oil filter, on the right is the adapter plate that hides behind the cooler.
Here is adapter plate removed, notice how studs will prevent oil filter from being installed.
Problem solved and now filter installs nice and tight, but not too right of course.
I don't follow. I understand how the rubber can wear the metal down over time, but are you not talking about the rubber of the tail shaft seal? If so, I don't follow how wear on the outside of the shaft affects the Inside of the shaft and how it slips on.
I'm talking about how the outside of the yoke can wear...not the inside where the splines fit the yoke.
By the way, when I saw that you live in Saskatchewan, it reminded me of the slowly melting mound of snow my sister and brother-in law call Mt. Saskatchewan in Winnipeg. Lol!
I have made some good progress on project zzzzzzz, just haven't been updating so here is some of my update, I will do more when I get more time down time with the car. I got my power steering working. I bought a ps line for a 95 caprice, it is maybe a foot longer than the line from the camaro. I got it bent up nice and had a great line to run it along the k member, but when I went to install it into the gear box it somehow stripped the first thread, which was weird because the 95 line feed in straight without any effort. So after some messing around and botching of the threads on my caprice line it was buggered beyond use (excellent use of $90). So I went to the factory camaro line and messed around with it, and found that if you run the line infront of the motor (between the fans and motor) it reaches with no problem. Also it clears the serp belt no problem, I prefer the route along the k member for tidiness so I probably will buy another line in the future but for now i am fine using the factory line. The reservoir I installed in the same location as most (the pass wheel well), however I utilized one of the strut bolts to allow me to install 2 bolts to hold the reservoir in place. I personally do not like hold anything inplace with a single bolt, so this worked well. By coincidence the ps reservoir has mounting brackets at different heights, so it's almost natural to bolt to the strut stud. It doesn't sit perfectly level, but I think it works.
You can the difference between the caprice line and the camaro one.
Here is the caprice line after it was bent to shape.
I have also taken care of the fuel line issue. I know there must be a cheaper option than the way I went but it worked flawless and did not require me to do a bunch of running around. Being that I live 1 hour away from the nearest major Center it's a pain to run in for a part and even worse to run back to exchange for the correct part. So in the end I am very happy with my result. I went with pure choice custom made line. I put 90 elbows on the end and straight on the opposite end. I like the 90 elbow I think it was the right choice. The length of the hose was 23", I think I might go a bit shorter like 22" for sure maybe even 21". At the price I was paying (and no returns on custom made lines) I was worried it might be too short but I think it would have been ok. Also with the hose I bought adapters for each end of the line.
Here is $230 CAD worth of fuel line materials. After exchange and shipping and duty it was pretty high but it worked flawless and looks good. Hopefully it's clear enough you can see part numbers to save yourself some searching.
Lines installed, leak proof, but as I said I would have preferred a little shorter, but it's alright.
Radiator is installed and working. The downside to running the 87 rad is that there are some hose issues to over come. The 95 rad has an extra port on the bottom drivers side which is for the oil cooler, while my 87 had an oil cooler the lines were tied in elsewhere and not direct to rad, therefore I had to do something with the oil cooler lines on the lt1. So I deleted the cooler and plugged he outlet on the pump, see earlier post regarding this. Next I had to deal with the other smaller outlet on the rad, located by the rad cap (not the one going to the overflow...that's a no brai er). The trouble here is the outlet on the water pump of the lt1 is smaller than the outlet on the rad, so I spliced to hoses together using a straight splice. Works well, but in the future I will look for a reducer, I like how that looks better. Speaking of reducers I used a flexible rad hose from napa and a reducer for the large lower outlet. Again the rad was 1.5" while the pump was 1.25". So the reducer just slides inside the other hose and when it is clamped to the pump fits like a glove and the clamp makes the seal. I used a piece of hose to connect my interior heat lines together to by pass for now because I am not sure I want to run lines there or not. As of now I am leaning towards not, since this car only runs in the summer months. The last hose on the top drivers side I used the factory 87 hose and just cut some off the end and it fit nice.
I finished things up these last couple of days! Well almost....my throttle is a hack until I decide what I want to do. Do guys bend the arm on the gas peddle, or use a stopper on the end of the cable, I also thought a guy could shim the cable on the firewall but that would look ugly. I am running the lt1 throttle cable and bought some aluminum clamps that you crush onto the cable (better get it right the first time), trouble is you have to cut the end off so you can slide it onto the cable. As of now that is my plan when I get brave enough. As for the firewall I plan on die grinding a thin washer to the shape of the cable and either welding or riveting it to the fire wall to fill in the factory hole. Right now the vise grips are holding just so I can take her for drive! The intake I ran the cold air system that came with the 95, it actually fits real nice but I ordered a 3" silicone extension so that I could put the filter a little more into the corner, again the length that it is will due for my test drive. I did however have to cut down the silencer on the duct because it would not fit as is. Basically just un clamped it cut it off as short as possible (without losing its circumference) and clamped back on, I may have also reversed the direction it sloped (I can't recall), either way it fits now.
I know it's a hack, but it's the weekend and I can't get parts in town, plus when I can I will have to wait for them to order them in and I want to drive this thing!
Last edited by 87iroctheo; 07-19-2015 at 11:26 AM.
My last step is to deal with the exhuast. I have a set of hedmen 68460 on the way, but I don't think they are going to work like I want. Either have to suck it up and go with dyno don shorties or try to cut the 68460 and try to adapt them to fit like I want. I have a lowering kit on its way as well which is why I am not interested running any exhaust pipe under the trans cross member. So I was playing around yesterday and for giggles I thought I would see how close the factory y pipes line up. The 4th gen was pointing the wrong direction and the cat hits a hump on the underside of the car. The 3rd gen y pipe looked to fit pretty close but has the wrong ends on it. So 1 hour later I had cut the 3 stud brackets off the 4th gen pipe and the 2 stud brackets off the 3rd gen pipe, cut a hole and welded a o2 bung into the drivers side pipe, and welded the 3 bolt brackets back together on the 3rd gen pipe. Next I bolted it up to the manifold and voila it bolted up to the cat back perfect! I have exhaust and am ready to drive this thing!
4th gen on left and 3rd on right, you can see how the cat points a totally different direction than the 3rd gen, maybe a cut up from there and some fab you could make it work.
2 cuts on bracket to seperate from old pipe and weld back together. If u leave a little metal on one cut you can bend it open and remove then bend back together, this makes it easier to keep bracket the correct offset so that it will line up perfect with studs.
ITS ALIVE!!!! After some tweaking with elec and playing with my tunercat to delete vats, cars, etc and block codes from the egr, CCP, air, etc. I am happy to announce the car runs and I think it will drive. Well I made it out of the garage anyways and back in. I am pumped to plate it Monday and try a test drive! Another program I found very useful for readin codes and testing my coolant fans (they weren't working), and live data logging is a program called scan9495. It's free and works awesome! I highly recommend it, and thanks to the dude who made it! If all goes well with the test drive the fun stuff begins!!! Modifying!!! I will continue my thread throughout all that stuff also.
Took care of the throttle last night as well as a few hours spent tightening up the tilt steering, I had a serious wobble to the wheel. The bolts were almost falling out! As for the throttle the aluminum clamp and washer seem to work great. I used a die grinder to round it out to the shape I needed and I also to thin up it thickness a little so the clips expanded easier. Works great, just need to drive it to the shop and tack it inplace and maybe throw a little paint on it.
Washer covers factory hole and seals it off great. Just 3 small tack welds and it's good to go.
Congrats on the start up. My swap is bogged down. I'm waiting for headers and gas tank install. Too many things happening here and the swap always seems to take a back seat.
Congrats on the start up. My swap is bogged down. I'm waiting for headers and gas tank install. Too many things happening here and the swap always seems to take a back seat.
04-13-2015, 01:21 AM
