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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.
Here's a few pics of the trans crossmember installed. It turned out o.k. Like I said, I think I'm just going to make one after everything is running. I want to incorporate all 3 holes to help with some strength, since the torque arm mount is a decent cantilever from the hole locations.
I think it is going to be too flimsy and it will twist. Better to take care of it now before something breaks.
Need to beef up the whole cross-brace. Extra bolt holes to the chassis aren't enough.
Interesting spot for filter. Most ones I've seen just has filter off the back of the charger.
Well, there's definitely no room right off the procharger, it would be a very small filter. The headers are pretty big, plus the brake master.
I'm not thrilled about running that much pipe (it is 3.5" dia) but at least I can use a very large filter.
Qwk-
Yea, I'm not happy with the current design. I'm not going to be launching this thing at the track anytime soon so it will handle just around town cruising while I get the basics ironed out.
I really want to make something that is fully boxed and maybe some C-channel that wraps around the frame rails or something. I have a rough idea in my head, but I'll see what I can come up with over winter.
I've finished the piping for the procharger. Working on a bunch of small misc. stuff.
Started the wiring...not my favorite, but it's sort of necessary...lol.
However, I'm taking a small break to build and finish my garage. It's a 36 x 24 (3) car. We got the foundation and slab poured last week. Started framing today.
Soon I will be "Indebt" hahaha.
Hoping to get back at this winter and have it running in the spring time. The biggest thing left is the wiring, which I keep putting off.
Wiring really doesn't take that long, just a lot to take in at one time. Are you converting the car harness or making your own with fuse/relay panels and stuff?
Sounds like good progress. Yeah I'm not looking forward to wiring but it shouldn't be bad I hope, and got a few friends that can help.
Congrats on the garage. I just built a 30x32, 10ft walls, white metal inside except back wall. One 18x8 insulated door with a Liftmaster 8500 opener (cleaner look). If you have any questions or need tips just ask. Also, check out garagejournal.com if you haven't already. Here's mine.
Sounds like good progress. Yeah I'm not looking forward to wiring but it shouldn't be bad I hope, and got a few friends that can help.
Congrats on the garage. I just built a 30x32, 10ft walls, white metal inside except back wall. One 18x8 insulated door with a Liftmaster 8500 opener (cleaner look). If you have any questions or need tips just ask. Also, check out garagejournal.com if you haven't already. Here's mine.
I would love to have that kind of room to work on mine. My little two car garage gets pretty cramped once you add kids bikes, four wheeler, lawn mower, and the list goes on.
I would love to have that kind of room to work on mine. My little two car garage gets pretty cramped once you add kids bikes, four wheeler, lawn mower, and the list goes on.
Very nice!
Thanks. Luckily, the house we bought also had a 10x12 shed so all yard stuff and storage stays in there. It definitely helps.
Great looking build you have there. Been away from the board doing other projects myself so missed the ongoing updates, but just read through your whole build thus far. I am in progress on pretty much the same setup, which I am planning to get back on the project in the next month myself.
Couple things I noticed that you may want to consider are placing the brake lines behind steering shaft to keep them away from the heat of the header. The other thing I noticed is you are running your fuel supply to one of the fuel rails and I am assuming you are going to install the backpressure reg off the other rail. You may want to consider a Y connection on both the supply and returns to ensure you have equal fuel pressure across both rails. She will be pulling a lot of fuel at WOT and could cause fuel pressure issues in the current layout.
For the air filter, I have seen some run straight back from the supercharger using two 45s to elevate the filter above the valve cover. Going to look into that option when I get there.
Was wondering if you had any T56 magnum install issues? From the research I have done, I thought there were some special mods that needed to be done for our application? Hawks sells a nice replacement shift guide for the console if you want it to be correct for the trans.
Would you mind sharing the power steering pump and steering box adapter fittings part numbers? Not even close to that part myself yet, but would save me some searching.
indebt, nice garage! I like that door. We went with 8' tall doors as well and I'm glad we did.
HP - I've changed my air filter location. It's tight, but it fits between the master and the valve cover. I'll get some pics soon.
No issues with the Magnum. It's just big and heavy. It takes up all the room in the trans tunnel. Had to open up the rear of the stock shifter opening by ~ 2" . The shifter sits perfectly centered in the console. My car was originally a manual car too if that matters.
I guess I should rephrase my complaint about wiring. I can do it successfully. It's just one of those jobs I don't really "like" to do. Whereas I like installing headers or supercharger. I can never get myself excited about installing fan relays or something, haha.
I think these are the fittings I used for the steering box. It was a long time ago I bought them.
EAR-961955ERL
EAR-961956ERL
QWK, yes, it's just a chore. Looks like your ride is coming along nicely! How are you liking the Holley software/ECU?
Here's how I'm running the air filter now. It's a 9" long cone filter from K&N. The piping off the D1SC is 3.5". It 's tight. That's the biggest filter I can fit. It would be nice to get some fresh air to it somehow. Maybe through the old wiper motor hole, LOL.
Here's a pic of the garage. It's coming along nicely. Can't wait.
36 x 24 with a 16 x 8 and 9 x 8 overhead doors. It's actually attached to the old 2 car garage. You can see the old side door still in place. There's a room above it that is going to be accessible from the 2nd story hallway. It'll be a bedroom/playroom for the boys.
So after we move everything out of the old 2 car, i'm going to convert half of it into a laundry room. We have no laundry room now.
I tell ya, car projects don't have anything on house stuff, lol
Just a small update. The iroc is on pause, but definitely far from dead.
When we initially started the addition/garage I had to push my car out of the old garage into the driveway and cover it up. The cover held up pretty good. I was getting nervous with all the delivery trucks and weather. So this past weekend my buddy helped me pull it into the new garage. I feel relieved that it's safe inside.
Addition is coming along nicely, I've finished the insulation and have a big drywall delivery coming this Friday. Just me working in the evenings and on the weekend.
I'm back! After hanging a ton of drywall, painting, and getting things organized I can finally work in the garage. Phew, the house has really been taking up my time this summer! The boys new room is 98% done, I just need to finish the closets out. We are planting grass and trying to do some landscaping before it gets too cold. Also, the power steering pump on my 4th gen died. So I wanted to fix that and added a separate P.S. cooler instead of the factory inline one that mixed dexcool with the P.S. fluid...
Nothing terribly exciting on the Iroc, just wiring...
Still trying to organize things, I had to put my garage stuff in the basement while I was finishing the garage. The 4th gen is in the foreground.
Current state of things. I was able to run the Holley wire harness where the stock one ran, through the passenger kick panel. Plenty of length. Its the LS1 main harness they offer.
Another shot:
Here's where it's coming through in the car. The 2 main engine connectors are off to the left. The main power connector is front and center, that one runs directly to the battery in the trunk. My plan is to mount the Holley computer behind the dash.
I mounted a Junction box in the old battery tray. Again, I made a simple plate that used stock holes in the tray, then mounted the junction box on that.
On a sidenote, can everyone still see my old pics? I can still see them, but with the photobucket nonsense I wanted to check. I'm using Flickr now, we'll see how it goes.
Continuing with wiring....
Thought I would share what I did for the coolant sensor. The Holley wire harness is set up for a 2 wire sensor, signal and ground. A stock 99-02 Ls1 ECM would then send the info to the dash. The 98 had a 3 wire sensor, signal, ground, and temp gauge. That's what I bought, since my car uses one wire from the coolant temp sensor to the dash. So here's how I modified the Holley harness.
This is the pinout for the 3-wire coolant sensor:
The connector I bought and labeled:
The Holley 2-wire connector, brown wire is the signal, black/white stripe is ground:
Stripped, soldered, and heat shrink. All I have to do is connect the green wire from the connector to the green wire from the factory harness which feeds the temp gauge.
I'll post up more as I go through the various sensors and connections.
Last edited by Thomas Aquinas; 09-20-2017 at 09:26 AM.
Did your IAT sensor come with that section? If so, where did you get it? Also, where are you going to mount the coolant sensor, stock or passenger side and tap?
The IAT sensor did not come with it. I bought a Delphi TS10077 off ebay. It has pipe threads, I wanted one that threaded in since I'm running boost. It's actually an IAT sensor for a GMC syclone.
I'm going to mount my CTS in the driver's head. These are AFR heads and that's where the sensor location is. Not sure if that's stock? Hmmm, I'm wondering if the passenger side head has a hole I need to plug, hahaha. Should probably check that out.
Both heads are the same (not specific to left or right side). The stock f-body CTS is located on the passenger side but that can interfere with the AC box of a 3rd gen car. Most people, including me, move the CTS to the driver side for easier access and serviceability. The right answer is whatever suits you best.
The IAT sensor did not come with it. I bought a Delphi TS10077 off ebay. It has pipe threads, I wanted one that threaded in since I'm running boost. It's actually an IAT sensor for a GMC syclone.
I'm going to mount my CTS in the driver's head. These are AFR heads and that's where the sensor location is. Not sure if that's stock? Hmmm, I'm wondering if the passenger side head has a hole I need to plug, hahaha. Should probably check that out.
Cool, I need to buy an IAT and a 98 CTS. On my lq4, stock sensor is on driver but I thought some people move them to passenger for better readings or more true readings, not sure.
My swap is slowly churning haha. I sold my D1SC, and bought an F1A, have my fuel pumps mounted and lines/fittings almost together/ran, intercooler should be mounted this weekend, and the wiring, the dreaded wiring. Honestly,I could probably hook my pinks up and a few others, hook up my fuel lines and start it. It's been a few years since I drove it and I'm over it sometimes. Need more time and money.
P.S. pump; and lines, routed to clear the bracket. Attachment 320319
Finally making some headway on my build and ran into an issue with the power steering relocation bracket install. The support arm that goes to the block was pushing the pump bracket away from the front of the engine. I had to elongate the hole where it bolts to the block to gain correct alignment for the serpentine belt. Gone unnoticed it would have likely thrown the belt. If you haven't already done so, I'd check the back of the crank pulley alignment with the back of the power steering pulley, just to be sure you don't have the same issue.
Just noticed you have a gap at the step where the bracket meets the block, mine had that prior to the elongation.
HP52TA - I'll have to double check that. The alignment seemed o.k. to me at the time, but it's worth a 2nd look. Thanks for the heads up.
Indebt- NICE on the F1A, I'm jealous. Have you looked at the new D1SC-X ? They make more power than the D1, but takes less power to turn it. There's a guy on LS1tech that just put up some dyno numbers on an LS3 vette. I'm keeping my eye on the D1x for sure.
Qwk - Yea, heads are the same. I looked at my passenger side and sure enough there's a hole. Good thing I didn't put coolant in yet, or i'd have a big mess. I'm going to put the CTS in the driver's head, since the temp guage wire is over there, a little easier for me. I have the 4 corner coolant thing so hopefully that helps keep the temps even.
It's a 12mm x 1.5 straight thread plug GM# 11610259. In case anyone is curious.
Awesome garage and glad to see the project rolling along. What did you end up going with for the radiator? I can't quite make it out on the pictures. Also did you reuse the stock fans?
Thanks man! I went to a griffin radiator a long time ago. I'd have to look up the part number if you need it. It's close to the stock size, I think I had to modify the little rubber "feet" on the upper and lower radiator holders to get it to fit.
I had a stock single fan with the LG4 which I removed right away and installed these:
Alright, so some big updates. I finished the wiring. I went to start it for the first time before christmas and nothing, it would just turnover. Seemed like I wasn't getting spark. I didn't have time to mess with it because of the holidays. Once I got some time in Jan. I started looking at all the sensors. The Holley system shows live data from all of them except the cam and crank. So I figured I better check those two. The holley does data logging as well as a system log. The system log will show you what is happening with the cam and crank sensors. So I made one of those ( I'll have to get a screen shot) and both sensors were good. Then I moved on to the coils. Looked over the wiring and I discovered I had them wired backwards....ooopps. Quick change of the wiring harnesses and fired right up.
I didn't get a video of the first start. Too busy checking things and whatnot.
Here's a video of the second start. It's a start-up tune, so it's still a little rough. It idles ok. I need to finish the exhaust, because I think I'm getting some fresh air on the O2's causing a false lean. But's it's good enough to get it running for now.
Guys,
Thanks a ton. It sure feels good. Now to move on to the underside. I really want to take care of the trans crossmember. I want to build my own, and make it much more robust than what I have now. I only have a few months left before nice weather.
Shifty - Right now I just stuck a bunch of pipe together to get the exhaust gases out of the garage. The plan is to run dual 3" pipes over the axle. Very similar routing to the new hooker stuff and the kooks setup on the 4th gens. I bought a pair of straight thru magnaflow mufflers with the inlet and outlet offset. The idea is to mount them like the other exhaust systems. They have a good size case, and its hard to tell from the video, but the actually do a decent job. I have my concerns about drone when cruising, but we'll see. I'll definitely post pics of my progress.
So a little more detail on the system log that the Holley system can do. Most of the time it is used to diagnose crank or cam sensor problems.
Again, I was having a no start condition. The holley data screen shows a bunch of info, pretty much everything. Fuel pressure, oil pressure, tps, iat, map, o2, injector pulse width, rpm (that screen you saw on the laptop in the video). Now I was getting a solid RPM reading and typically if you're seeing the rpm move when you're cranking it's not the crank sensor. Anyway, so I set it up that when my oil pressure got about 5 psi the system log would start and last for 15 seconds. The green is the crank signal and the blue is the cam. And the results look like what is typical. If the either one of the blue or green was broken up or flat, then I would look more into that sensor.
Also, forgot to mention about the oil pressure gauge.
After reading around that people have used an oil pressure gauge from ls1 f-bodies I decided to try one. I bought one for a 2002. I am using my stock 1986 oil pressure gauge.
It does work, but only kinda. Seems like it maxes out around ~35 psi. I have it installed in the standard location for an LS.
Now I also have a 2nd sensor for the Holley system installed above the oil filter (you can see it in an older picture). That sensor reads 60 psi on a cold start. So quite the difference.
I have a safety cut off in the computer right now, so if the oil pressure drops too low, it will kill the engine.
I might try putting the old sensor back on with an adapter, but not right now, I don't feel like pulling the intake.
Just wanted to report my findings.
The coolant sensor is working great, the gauge is reading the same as the computer so I'm good with that.
Also, some small updates. I bought some Alston subframe connectors. I already had spohn's from a long time ago. Seemed like everyone had positive reviews with them so I figured it couldn't hurt to add more bracing, especially with the added power. The fit was "good". The driver's side fit really nice, just a small tweak to the rear mounting location to get it to fit tight. The passenger side fit great at the rear, but not so much at the frame near the trans. I had to add about 1/4" plate to make up the gap between the frame and the bottom section of the mount. Not a huge deal, I get it with these cars. Also, there are two cross bracing pieces that go from the spohn subframes to the inner frame. The drivers side was fine, didn't interfere with the Alston's. The passenger side brace had to be cut, but I attached it to the Alston's.
The second reason I did this was to add a third mounting location for the transmission crossmember. The factory 2 bolts are fairly far forward compared to the transmount on the T-56.
So I'm making a crossmember that will hopefully fit with Alston's, the T-56, an aftemarket torque arm, and allow me to run dual 3" pipes.....phew! So far so good, though. I've made the two pieces that fit along the rails.
I'll get some pics up this weekend.
So here's where i'm at so far. The frame rail attachments basically had to be offset to mount around the Alston's subframes.
I'm using 3/16" thick mild steel for everything, except the vertical plate to the left of the mount, that's 1/4"
I'm using the stock 2 transmission mounts locations, but I'm adding 1 more on each side on the Alston's, you can see the holes I have drilled already. I think I might weld a stud to the Alston's.
The only things I have left are to figure out the torque arm mount, weld studs for the 3rd attachment point, and box in the rect. tube on the passenger side. Oh and paint it.
Sorry for the shitty pics, not sure what happened with my phone? Maybe it was the operator.
[url=https://flic.kr/p/Pvehb9]
A couple on the car: (I still need to paint the subframes)
Looks good man. You might want to add some round gussets on the driver side (Between the frame mount and the trans mount). That will help firm up the integrity of that side but also allow for your exhaust to go through.
Thanks. I hear ya on the gussets. I'll probably wait until I figure the torque arm mount, because that's area it's going to be. I'm think the T/A mount is going to be a little trickier than I first thought, running out of room, haha.
So, I'm about 95% done with the crossmember. I started on the exhaust just to see if I have to change anything on the crossmember before I paint it.
There's a few places I have to grind for some more clearance, but really not that bad.
Here's where I'm at with the exhaust. Getting around the crossmember took a while. Everything is done before the x pipe. So I'm hoping the rest won't be as bad.
Seems like the ground clearance is going to be good. Hard to tell since the car is in the air, but looks pretty good so far.
Last edited by Thomas Aquinas; 11-07-2018 at 11:34 AM.
Finally finished the crossmember and the exhaust. Only have pics of the crossmember. It's all done for now.
So, for paint, yeah..All of the suspension stuff is red, but the Alston's came in black. So I painted the crossmember black. The torque arm is from spohn and I've had it forever.
I'll get some pics of the exhaust after I put it on the car. Also, finished up the wiring for the trans. to the holley.
Almost done and ready for a road test soon.
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Last edited by Thomas Aquinas; 06-10-2019 at 02:03 PM.
So, I finally got the exhaust done(ish). It's close enough for now, I was kinda getting sick of working on it. I need to go back and fix the driver side over the axle pipe. I have it too close to the rear-end. Discovered that when I was lowering the rear of the car with the ground control adjusters. So the rear is sitting a little higher than I want at the moment. But I'll work on that later, I really want to get this thing on the road.
The mufflers are Kooks, the same ones that come on a dual 4th gen setup. They fit pretty much perfect. The only downside I noticed is that I can't center the pipes under the bumper due to the trunk well and gas tank. The driver side muffler is a couple inches more toward the outer of the car than the pass side. Not terrible, just something I ran across with the tape measure.
I chose to do these simple exhaust tips. I didn't want some big obnoxious ones, and I was more concerned with tucking the mufflers. Also, this way was super cheap, lol.
My thought was to paint it black to match the headers. Not sure if I like the result or not, but my son (6) and I had a good time paint it, so that was cool.
Last edited by Thomas Aquinas; 06-10-2019 at 02:03 PM.
Some small, but good updates.
I was able to take it out on a couple test drives. The first test drive was not so good. I had some problems with the tune and it wanting to stall slowing down to a stop and it didn't like part throttle acceleration. Short trip, but I got some good info to make some adjustments. Second drive was much better, cruising and small acceleration felt good. Even got into a little boost.
Recently I'm just trying to work on idle. I have it pretty solid at 800 rpm. Still needs a little more work, but I need more time...hahhaha.
Also, trying to set up the speedometer. So I have a VSS signal coming into the Holley and ppm signal going out to a dakota digital box to drive the stock mechanical speedo. We'll see how this works out. I haven't tested it yet.
Last thing to do is mount the computer under the dash on the passenger side so I can sit a person in there to help with a few things. I'll get some pictures of that.
Here's a much better Idle video. It definitely needs a wash.
Also, wait till the end. You can see my girl come into the picture in the upper left yelling at me to turn it off and get inside. LOL.
08-16-2016, 04:00 PM
