When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
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.
I've had the LS6 in the car for about 5 years (wow, time flies).
The LS6 (or LS2 since its the same HP), to be honest, probably the perfect engine for this car. With full bolts it kicks out about 430 HP in a 3200 lb car. Just a ton of fun to drive, but its not "too much" car... very easy to drive and live with. I was perfectly happy with this motor.
Then my friends started to make some serious power. Then I decided it was time to be dumb.
I've just started this and with a baby and toddler, its going to take some time.
I bought a LS7 in Warren MI a few years ago and have been sitting on it while I saved up to do it how I wanted. To be honest, I got hosed on the engine. The guy I bought it from said it had piston slap but aside from that was good. Turned out to have 7 spun bearings and the rods and crank were trash. Block was salvageable though. After selling the heads, it wasnt terrible financially, but like most things, turned out to be more than expected.
I was able to source a new GM crank and found a set of good low mileage rods that checked out perfect. I wanted to go with the TI rods to save on weight since its going to be a NA motor and Im not going to put a ton of miles on it.
I dont want an all-out race motor, but I'd like to make as much HP with this thing without going with a crazy cam so I'm trying to squeak out a few HP here and there with things like a crank scraper and lighter pistons. It should make north of 600 rwhp based on similar LS7 builds in C6s. We will see.
Plan for the engine:
LS7 .010 over
JE forged pistons (11.7:1) - 426 grams per slug (down 60g over stock)
GM crank, OEM TI rods
Mamo 265 heads (with larger exhaust valves)
Mamo spec'ed cam
Mamo ported LS7 MSD Airforce intake manifold
Johnson short travel lifters
Yella Terra 1.8 rockers
Monster LT1-S clutch
Improved Racing crank scraper
2" stainless headers
I'm going to try to use the E38 PCM so I can retain AC and cruise semi-easily. We will see how that goes. Also going to keep the dry sump because it seems like a fun thing to have in a thirdgen.
I had the short block assembled at the engine shop to save some time. It is done and I hopefully will pick it up on Wednesday. That should put me right on track to have the swap done by 2037.
I'll get some pics of the engine when I pick it up!
The only thing I dont really have figured out is wiring. I'm not great at wiring, I'd like to buy a plug and play harness for thirdgen swaps with all new wiring, but it seems like most of the places have moved away from them and only do universal ones. Anyone have a suggestion?
Man its tempting. Id have to run the Dominator since I'll be going DBW and its north of $3k with everything...
And I owe you a lot of beer, I have learned a ton from your thread.
Rest of the drive train... have a built T56 already, and then probably a CF driveshaft and 9". Not sure which one to go with. Those are 2037 problems ha!
So the current fun is trying to figure out my head gasket. I think its going to end up at .036 but I'm getting conflicting DCR numbers. When I use the calculators that want duration at .050 the DCR comes out at 9.1:1 which is too high, but the ones that use advertised duration come out closer to 8.3:1 (cam motion's app seems to be the best). I'm going to assume the advertised numbers are better and hope for the best.
At least the engine is finally home and on the stand. Are any of you guys running an oil t-stat? I was thinking about the improved racing one. JE Pistons with 2cc relief Mopar carrying a Chevy. This is atypical.
Use advertised duration for DCR. I can run calcs for you if you give me the physical data. (I have a nice spreadsheet I created)
I chose gasket thickness solely based on how much quench I wanted. And then chose cylinder chamber volume (cc) to achieve the compression ratio I wanted.
The tighter the quench the more complete the burn and more resistance to knock. Shooting for 0.035" quench with stock LS7 rods, and definitely no tighter than 0.033" on any cylinder. Any tighter and you risk piston touching cylinder head. I used a piston bridge to measure piston above deck for every piston. Turns out in my case that one bank was higher than the other. I wanted to run a 0.042" thick gasket on one side, and a 0.038" thick gasket on the other, but Cometic doesn't make either so I settled on 0.040" gasket both sides. I ended up with 0.035" average quench, with values ranging from 0.0335" to 0.0370".
The data I've been using is:
77.5 intake close (advertised duration)
4.135 bore
4.150 gasket bore
.036 gasket thickness
.013 in the hole for piston to deck
70.2cc chambers
2cc reliefs in pistons
Shifty and I have been running the calcs and this seems to get me to 8.3:1 DCR which isnt perfect but should be fine for a pump gas motor. My quench is a little high at .049.
The shop only measured one piston on each bank and came back averaging .013, you and Tony both seem to recommend to measure each piston so I'll have to figure that out. If .013 is really a good number, I could probably get away with a .030 gasket which I think gives me a DCR of 8.43 and quench of .043 which I'd be good with. My SCR with that. 030 though would be 11.77 which feels a little high.
I'd rather have the actual cam specs. This way we can double check if I also come up with 77.5 degrees ABDC. Your cam closes later than mine, and mine isn't exactly small (maybe about Stage 3.5).
Yes, I get 11.55 SCR and 8.25 DCR with 0.036" thick gasket. I assume you have 4.0" stroke and 6.067" long rod. But you're going to need a much thinner gasket anyway because your piston is down in the hole.
Stock LS7 pistons are just barely out of hole and use 0.040" gaskets safely without even measuring anything, or as little as 0.036" gasket if it can be backed up with satisfactory measurements. You can't go by these rule of thumb with your pistons being down in the hole. You're going to end up needing somewhere around 0.025" gaskets if your measurements hold consistent. It might be smart to call Cometic and have a discussion about how thin can they go and still seal reliably, and what thicknesses do they make? They don't make just anything you want because the steel shims only come in certain increments of thickness. Also, I'm wondering if JE Pistons actually intended the block height to be milled more?
Tony is going to tell you that he doesn't pay any attention to DCR because it can't be measured on engine. He only pays attention to SCR. But.... I hunted down all the LS7 Mamo builds I could find on the forums and noticed he nearly always hits 8.68 DCR with his 93 octane pump gas builds.
My suggestion is get the measurements of piston height to deck. That will drive the discussion.
The shop did not deck his block which I find kinda odd. GM's deck surface isn't very flat and the same shop took .004 off both decks on my new LS3 block. Maybe the LS7 deck is held tighter from the OEM.
His cam specs are
Advertised Intake: 294
Advertised Exhaust: 309
Intake at .050": 245
Exhaust at .050": 258
LSA: 114+4 on a 110 intake CL
.623 lift both I/E
He has more overlap which will drive the DCR down a bit but 8.31 (ABDC is 77.5) is what I believe he will end up at (good for 91+ octane). I am going to play with some gasket numbers to see if I can tighten up quench without affecting DCR. My cam on the other hand is much smaller with little overlap and will have a high 8.7 DCR, which "should" be ok on 93 octane. When you see me start a thread turning my 377 into a 416 you will know that my DCR was in fact too much.
Oh, you've got what I call the "mystery client" cam! Made 650 RWHP with 12.0 compression and 93 octane. That was the top dog when I benchmarked different Mamo LS7 combos a few years ago (I've got a list of them).
So with Chuck's cam I get intake closing at 77.0 degrees ABDC. If you do a 0.036" thick gasket then quench and compression ratio are going to be too soft.
A) That brings you in at 0.040" quench, 11.77 SCR, 8.45 DCR.
B) If you also mill the block 0.004" then you'll get 0.036" quench, 11.89 SCR, 8.53 DCR
C) If you leave the block alone and mill the heads to 69cc (about 0.010") then you'll get 0.040" quench, 11.97 SCR, 8.59 DCR
Really need all the piston to deck measurements though.
I think Tony was conservative in his SCR + DCR targets for me because I asked him to build it for 91 octane. We do the Hot Rod Power Tour every year and sometimes you'll be in smaller towns where 91 is the best you can find. I know I can carry some octane booster but I'd rather not rely on that.
I ordered the tools to measure the deck clearance, they're supposed to get here today so once I figure out how to do it I'll post them up.
The only thing I dont really have figured out is wiring. I'm not great at wiring, I'd like to buy a plug and play harness for thirdgen swaps with all new wiring, but it seems like most of the places have moved away from them and only do universal ones. Anyone have a suggestion?
Shifty and I both measured the deck height independently and came up with .013-.014 on average. We went with the .027 gasket, which is the smallest we could get. I know the .040 quench isnt ideal but its in the ball park and I want to keep this thing rolling. Hopefully that shows up next week.
Ive been trying to figure out cooling. Qwik -- which radiator did you end up running? I assume stock isnt up to task for this.
My cam on the other hand is much smaller with little overlap and will have a high 8.7 DCR, which "should" be ok on 93 octane. When you see me start a thread turning my 377 into a 416 you will know that my DCR was in fact too much.
I mean your 1.6 liter engine really wont allow for that much cam.
Qwik -- which radiator did you end up running? I assume stock isnt up to task for this.
I bought the radiator 20 years ago and not sure any more exactly what it is, or if it is still available today. Of course being old it fits perfect. I think it is a direct-fit brass Modine that was advertised for use with big block swaps. Not even sure what thermostat I have because it came with a new, second-hand water pump that I bought from a guy on LS1tech. I assume the thermostat is just stock LS1 F-body. I also use stock V8 dual fans.
All I know is my cooling system is FANTASTIC. Engine comes up to temp very quick and then holds rock solid. My local speed shop even made mention that my engine temps were the most stable they had ever seen on dyno.
Finally got the head gaskets and was able to get a little bit of work done. Having trouble uploading images, I'll get those added in a bit.
Did go with a .027 MLS Cometic gasket. Worked out well, although I had a freak out moment and thought I installed the pass side gasket wrong because the "front" wording on the gasket was facing down instead of up like it was on the drivers side. But the two were the same part numbers so it would have to be upside down. Either that or I'm going to have some terrible cooling issues.
I did do what Mamo recommended which is to get a cheap-o crockpot and then get some low weight synthetic oil up to about 200 degrees. Once it hits 200, unplug the crock pot and throw the lifters in there for 2-3 hours. Once it all cools down, take the lifters out and work the rollers back and forth. They are much smoother after doing that compared to when I took them out of the box (using the Johnson link-bar low short travel lifters).
Used ARP bolts for the heads too. The kit is nice, but I'd recommend ordering the thread lubricant they use in the big can instead of just using the packet. The packet works OK but the brush with the can is a lot nicer to use. So the heads are on.
Next up is measuring for pushrods. From there its only 28 more years until its running.
Slowly making progress on this thing. I'm trying to be as thorough as possible on this build so its a lot of researching and measuring, not a ton of measurable progress from the last update.
I did get the harness buttoned up with Pocket. Its supposed to arrive tomorrow and looks killer from the pictures. It integrates the Aeromotive fuel pump kit and AC emulator as well as a few other trick pieces. He was really wonderful to work with.
Also spent a lot of time talking to C&R on cooling. I ended up going with their LS swap radiator with -20AN fittings for both in and out.
The hardest thing to figure out was fans, I wanted to go with PWM fans so I could have variable speed on them. Ended up with two brushless Spal fans that have the integrated PWM controllers. The whole radiator/fan setup should be awesome assuming I can control it with the E38 ECM. I called Spal and they said to set the values between 16 and 91% for the tables. I noticed the 5th gen fan tables line up very nicely with that guidance, so it may be a good starting point.
C&R also had an overstocked oil cooler that uses one of their racing cores in a small overall design which I'll be using.
Currently measuring for pushrods which is one of the final things for the engine before I can finalize the assembly. The Holley low mount AC bracket fit on very nice, I hope with the Sanden SD7 it clears the BMR k member. I'll order that compressor next week to compare to the OEM CTS-V which is about 1/2" too long... the back of the housing barely hits the k member. If not I'll have to use a high mount but I'd rather avoid that.
Things continue to chug along. I finalized my pushrod measurements. That was a lesson in patience as I had to remeasure a few times as I learned how to do it better and check better as I went. Those should get ordered this week. After that the engine should be done, I have the Mamo MSD intake ready to go.
Pocket harness came in the mail. It is beyond my expectations esp with all the customizations.
Grabbed the GMPP AN conversion kit for the oil pan and the Improved racing low-profile oil thermostat. The improved racing stuff always seems to be so well built.
Next up to order will be headers and clutch. Right now I have the 1 3/4" Hawks/Stainless on. Holley still only makes the blackhearts in 1 7/8", so I guess my only option is the 2" Hawks/Stainless. For the clutch I'm going to do the monster LT1-S twin disc.
I imagine this will slow down a bit over the summer as I'd like to drive it with the LS6 while its nice. Or I'll get anxious and pull the ls7. Still not sure.
Woven loom harness Had Pocket eliminate the white weather pack for the coils for a cleaner install
This care package from C&R showed up yesterday. Oil cooler is pretty massive, although the logo is upside down... oof. I called and they said they would take care of it once they re-open. Shroud is a massive upgrade over stock in the looks department. The LS swap radiator is just beautiful. Spal brushless fans with integrated PWM modules. -20 AN on both upper and lower fittings
The whole covid deal has pretty much brought this to a grinding halt because nothing says "if you go outside to work on the car I will murder you" more than constantly having the kids around. Ive been accumulating parts but thats about it...
I did get the valve train finished up. Custom length Manton pushrods with the MMS YT rockers. I measured wrong the first time I went through the process, then thought I was in good shape until the second to last one I had to measure was about ~.3" longer than all the other ones, which made me think I did it wrong again. It turns out there was just some variation in that rocker's pushrod seat. Everything buttoned up fine. For LS7 folks, you need the Comp Cams 7703 length checker tool, and save one of the stock push rods for the opposite side you're working on. Katech has a good video on how to check with OEM rockers and an LS engine, its pretty close to what you do with the shaft mounted ones and very easy to follow. Just a reminder to anyone doing this in the future - the longer bolts are for the exhaust side, shorter for the intake side. Intake side bolts required thread sealant as the threads protrude into the intake path. Exhaust side I just used ARP thread lube.
At this point I'm trying to figure out PCV and fuel system.
I wanted to run the PCV system similar to what OEM does with both valve covers t-ed together and run to one side of the oil tank, then the metered fresh air source from the intake duct to the other side, but the aftermarket tanks seem to want you to run an external breather can and I dont really want to. The ARE 7020-A tank may solve this problem, hopefully I get that figured out. I'll be using the Mighty Mouse wild catch can system in there too, working with them on exactly how I want to plumb it. They've been awesome to deal with. These are the parts where I'm trying to squeak as much HP out of it as I can without using a crazy cam.
Fuel system I dont know what to do. I have the aeromotive stealth 2 tank with the -6AN lines and the MSD fuel rails. The local shop I'm going to use for tuning recommended to use a either a horse-shoe style system (fuel pump feed -> first rail -> cross over -> second rail -> regulator -> return to fuel tank). I like the horse shoe, but aeromotive said that would only support 600 rwhp which would be a little below where I hope to end up power wise. I'm not sure if its better to just do it like I have with the LS6 and run it from the tank to the regulator, then regulator to one rail, cross over and dead-head into the second rail. Ive read the horse shoe style is supposed to be better suited to fuel pressure drops, but if I have an NA engine maybe that isnt so much of a concern? Any help here would be appreciated.
Ready for rockers
Ended up with 8 different push rod lengths after grouping similar measurements and rounding a little to account for variation in measuring and manufacturing
Mamo Yella Terra rockers installed
Valve train done, obligatory photo with the MMS MSD Airforce
I decided not to pull the motor until the fall since its so much fun to drive in the summer. I'm tackling a few things in the mean time one of which is steering. I'm pretty sure the last time someone touched the steering was when it was being built in 1991.
Steering box is a 12:1 TurnOne, cooler is a C&R, and I'm using a .149 orfice for the ps pump to limit the flow to 3gpm which is what this box wanted. I had previously just been running whatever the stock CTSv flow was and from what I read its way too much and you end up just returning a ton of it.
I couldnt find a good replacement for the OEM power steering revisor with AN lines for the CTSv bracket, so I'm trying to hack together a G8 bracket and aeroflow res to bracket. We'll see how it all goes. Progress so far..
C&R cooler mounted under drivers side battery tray. Came out really nice, hopefully there's enough airflow Need to get the pitman arm on it now Two things 1. I need to degrease the car badly. 2. You can see where turn one removes the 4th ear on the saginaw 600 box. I think other companies (DSE) leave it on and you have to cut it off, so this is a good reference point
Steering is done. The biggest improvement to me is when you're turning one way then you need to turn the other, the stock box was so lazy and sloppy. This more much inviting and smooth just during that transition. I wish it was a little more twitchy on initial turn in but if I feel that way in a year or so I'll have it changed to a 10:1 box. Overall so much better.
The Earl's ultrapro line is a dream to work with, literally you can make a line in <5 minutes and you dont cut the crap out of your hands, but they discontinued it in 6AN due to supplier issues evidently. Which is great because that is what size Aeromotive recommended for my fuel line.
G8 bracket welded to spacers then bolted to the stock CTS-V PS bracket Aeroflow res on. So much better than the plastic OEM piece. SS high pressure line from pump to box, then Earl's Ultrapro for the cooling lines and return. It cleaned up the engine bay so much. Will be happy when I do the LS7 swap to run a consistent looking line for PS, fuel, PCV and oil.
Literally a year hiatus on this until my wife of all people started to yell at me that I need to get back into my hobby. The plan is to get the engine, trans, fuel tank, and dash out then get it to a local fab shop for a couple things ... decided to go with the Restomod AC unit based on the Level7 91 Z28 and how well that looked. I'll also have them mount the oil tank and weld in the DSE fuel tank trap for for the hatch.
The flip side of this is... the car needs a full restoration, esp the floor boards and pinch welds. But that would require me to take the car down to the shell which I'm not really excited to do since it pushes out my time line another 38 years. I just have a feeling when it goes to the shop they'll talk me into it. We'll see.
Almost ready to be pulled These race ramps cribs make the car less hateful to work under. Except the rust is still there.
Its going to be dry sump - sorry for not responding earlier. The front oil drain is what I'm worried about on the OEM pan, even with this BMR k member.
The underside of my Camaro is a rusted mess ... rockers, floors, fenders. So I finally took the plunge and am sending it off for a full resto job before putting the LS7 in. The estimate is about six months of work, so we'll see. I cant do body work nor do I have any desire to learn so I'll have to pay. My only requirement was "no rust anywhere." Ha. They will do a bit of fab work for me too... Restomod AC, mount dry sump tank, DSE fuel door, DSE sub frames. I assume this pushes out my timeline to 2051 now.
Last day in the garage was Monday. They hope to start on it in a couple weeks.
Where to re-start with this thread. The short of it is ... I saved enough money to have the green car's body restored and the rust taken care of. Selected a shop locally who was recommended. That shop sat on the car for over a year doing essentially nothing with it (at least they didnt charge me), went out of business, and wasted a lot of time. The main mechanic and body guy took over the shop, moved out a bunch of half finished cars that had stalled, then started working on my car. We found out there is just too much rust. I love the teal car, like ... I've owned it since 1999. But I would have had an amount of money in it that made no sense, so I had to make the decision to pull the plug on that.
I found an amazing 1991 Z28 on this forum from a member who owned it for the last ~15 years, but with family obligations just couldnt commit to doing the build he wanted. He had pulled the engine and trans, so I bought it as a roller. The body is nearly perfect. So the plan is to tear down the new red car, pull most of the parts I have on the teal car and put them onto the red car, along with fab and a really nice paint job, then put the LS7 & t56 in it. Its not going to be a show car, but I want it to look as good as I can for something I plan on putting some miles on every year.
I usually do all my own mechanical and tear down work, but with work and kids now I'll have to rely on the shop a little more than I normally would so we can keep making progress. They just started tearing down the red car last week. Lets hope for some consistent progress....
Hoping some of the folks on here can help. My front drain plug on the LS7 pan hits the UMI road race k-member, the exact same situation as 82IMSA ran into here...
I dont really want to notch the k-member, but obviously I'd like to be able to drain the oil
My oil tank has a drain on it that's easily accessible, and my AN fittings coming out of the pan to the oil tank should be accessible. If I drain the tank, disconnect the "in" AN fitting and drain that, and drain the pan via the second drain plug on the drivers side, will that get 99% of the oil out, or is there something unique about what drain plug in the front of the sump? It looks like it it just allows access for oil to drain out of the feed (or "in") side of the oil channel cast into the pan, so I'm really hoping disconnecting the AN fitting will do the same thing. That would allow me to block off that front plug and still be able to change the oil.
Continued progress. Engine, t56, accessories, are in and mostly working. Suspension was swapped from the green car to the red car including brakes.
The holley mid mount system clears the k member really nicely. The only thing that looks tight is the return fitting for the steering revisor only has about 1/4" clearance to the steering box. Unfortunately I had already bought a C6 ATI damper which doesnt work with the mid mount, so I'm rebuying that. Evidently when you dont do anything with your car for three years things change.
The idler arm and center link hit the front corner of the oil pan, of course. The LS7 pan is a doozy to get right in these swaps evidently.
Radiator, oil tank, breather, and hydraboost/master cylinder are next... along with DSE subframes. Then its getting the restomod AC stuff figured out. Its killing me to let a shop do most of this, but at least I can be involved with decisions and buy parts (Mr Summit racing loves me right now).
Keeping on with progress. The biggest issue so far has been working around the OEM LS7 oil pan. The deeper sump in the front has created a bunch of fun issues. The front drain plug interfered with the UMI road race k member (another member had this same issue, I dont know why I thought mine would work, blah).
We were able to work around that, but now I'm dealing with this fun - full steering lock right works, my tie rod just barely clears the left side of the pan, but approaching full lock right the tie rod hits the side of the pan. The pan is bulkier on the pass side because thats where the oil passages are machined into the pan to go to/from the tank. I think if I adjust the idler arm down to its lowest position it will just barely clear, but that is going to put me about 5/8" difference height wise between the pitman arm and the idler arm (idler arm side will be lower). The extra depth of the LS7 pan vs the fbody pan really makes a different.
This is looking from the nose to the front of the pan. You can see where the tie rod and idler arm just barely dont clear the pan. The LS7 pan is about .6" taller than the fbody pan. Side view of where its hitting. Blah. Even if we slide the motor back as far as it can go, the steering components would still hit the pan.
If you're interested, I could take some measurements with my BMR K-member. Pretty sure it sets the engine higher and further rearward. I have a Holley 302-1 pan with height of (2.42 inch + gasket) at the front which is quiet a lot taller than the LS7 pan at 2.0 inch. The engine is so high that I can barely close the hood over that MSD intake. The BMR K-member itself is not terribly sturdy though.
If you're interested, I could take some measurements with my BMR K-member. Pretty sure it sets the engine higher and further rearward. I have a Holley 302-1 pan with height of (2.42 inch + gasket) at the front which is quiet a lot taller than the LS7 pan at 2.0 inch. The engine is so high that I can barely close the hood over that MSD intake. The BMR K-member itself is not terribly sturdy though.
You are right -- the engine seems too far forward. I ran the BMR with the LS6 and it was definitely more rear ward. That blows my mind the 302-1 pan clears for you. I'm using the UMI poly engine mounts, which they said would be the same height as the OEM 4th gen fbody. I could try my OEM clam shell, I dont know if they work with the UMI k member though... hmm...
Continues to move along -- we're getting close to plumbing and wiring. Pocket made me a harness a few years back for the RS that I think should 99% work, but have to figure out any wiring differences between the RS and the Z28. I think the primary one is the speedo in the C207. I'm not sure if anything needs to be repinned in the C100.
DSE subframes are welded in and rust protected. This was a bit of a PITA evidently. ARE dry sump tank and breather. Its the 2 gallon tank and theres good ground clearance from the bottom of the tank, which I was worried about. Restomod AC system and bulkhead are mounted. We put the box in the same spot were basically the stock one was, where Level7 put theirs in the 91 Z28 they built (there's a really good video on youtube about it). Once we get past fab, the rivets for the firewall will come out and it'll be welded and smooth.
Some more progress. The BTR valve covers with the built in ORB fittings for breathers are really nice, and they're tall enough to clear the Yella Terra rockers. Next up is rear, fuel lines, exhaust, and brakes.
I ordered a Trick 9" with 35 spline axles, TruTrack, and 3.70 gears. The M12 gear set in the T56 I have out of an 04 CTSv is steeper than the fbody t56, so I didnt want to pick too crazy of a gear for the rear end.
Im going to be running CTSv2 brakes front and rear, the old car had the 04 CTSv 4 piston brakes, these will be the 6 pistons in the picture below. They're similar (or the same?) size to the calipers on my ATSv, but when they're not on a car they just look so freaking huge. Scott from bigbrakeupgrade has been awesome to work with. He did the brackets my old brembos 10 freaking years ago, too.
Shifty talked me out of doing true dual 3" exhaust back given his car sounds like John Force's car and I just cant do that driving for hours in the car. I ordered the Mufflex 4" single in/out spintech system. So it'll be 2" primaries, 3" collectors, dual 3" cats, then y to a single 4" back. I hope I can use some of my existing 3" y-pipe, but I'm sure I wont be able to and will have to spend $3.6 billion on new cats and fab. I know I'll give up a little peak HP, but I'd also like to enjoy driving the car. I have a feeling based on the videos that qwk has posted it will still be plenty loud ha.
I always get obsessed with something dumb and minor during the builds. This one was fans. I really wanted to run brushless PWM fans and control them with the E38 directly without any sort of aftermarket controller. I dont know why this was important to me, but I'm trying to keep as much OEM functionality as I can as I figure GM spent a lot of time getting it right. I bought my radiator and shrouds 3 years ago from C&R when I thought this was going to be a pretty quick swap (spoiler alert: it wasnt). The whole radiator and shroud setup is beautiful and came with 2x 12" spal brushless fans. What I didnt know at the time is that the aftermarket spal brushless fans have a SLIGHTLY different controller on them than the GM OEM spal brushless fans. The aftermarket one takes PWM negative signal, and the GM takes a standard PWM signal. With a holley Terminator you can flip the fan output to PWM-, but with the E38 you cant - I called HP Tuners and they validated that.
So basically when the E38 sends a signal to command fans at 30% speed, the Spal OEM GM stuff runs at 30%, but the aftermarket stuff would run at 100 minus 30%, so 70%. If the E38 commanded 40%, GM would run at 40%, aftermarket at 60%. There's a super long thread on it on the HP Tuners forum (below), but it sounds like trying to tune around it and change all the tables ... works... but because your table goes in increments of say 5%, as the fan ramps up and down it does funky things. I didnt want to get rid of this shroud though because it was so nice. I could only big single GM Spal brushless fans - C7 corvette, ATSv/CTSv, Camaro, etc. all use them but they're like single 16"+ blades. I randomly came across a thread where a guy found GM put dual 12" brushless fans in the 2016+ Chevy Volt. So I took a chance and bought a shroud and fan assembly from a junkyard from a 2016 Volt. Amazingly (considering my luck) its physically the exact same fan as C&R put in my shroud and the Volt ones bolted in exactly the same, so now I have fans the E38 can control like OEM. Awesome. Only 3.1 billion more things to figure out.
I was worried we'd have to extend the coil harness since the BTR valve covers relocate them, but it all worked out well with stock length. The pocket harness is really nice.
Wilwood MC on the hydraboost. There's just no room with that strut cap which Shifty experienced with his baer remaster. Ill do the same thing he did with cutting a relief into the cap and welding a flat plate in.
2016 Volt fans and shroud
Spal aftermarket 12" fan on top, Volt fan on bottom.
Have not posted an update for a while. I should have taken a few more pics, but I was in a hurry this morning when I ran up to see the car. All the big stuff is basically done. Now its onto the 1.3 billion small things. Brake lines, fuel lines, ebrake cables, Restomod mounting and wiring are all done. Its mostly finishing up interior wiring, mounting the thirdgenguy fuel door, over flow tank, etc. I'm hoping it'll get blown apart and into paint & body soon. Only four years left.
Couple things to note ... the bmr rear sway bar hangs very low with the trick performance 9". Its bent pretty aggressively downward towards the floor, plus the sway bar mounting brackets on the 9" hang about an inch lower than how the OEM rear mounts (see pic below). I'm going to buy the DSE one and see if that tucks up higher, if not we'll have to hack apart this sway bar mount and use the 3" u-bolt clamp that comes with the DSE kit.
Also the MSD Airforce bashes into to the stock wiper motor, at least with the UMI k-member placement. They found a chrysler motor that has the same connector as OEM, but had to fab up a mount to fit it into the stock location. I dont think it has intermittent settings but if I'm driving this in the rain I'll be too busy trying not to die to be focused on how fast my wipers are going.
On wards and upwards.
Wiper motor as noted above. Everything else looks good and this is basically how the engine will look.
The mounts for the rear swaybar.
The new toy. I took the old CTSv brakes off the Camaro when I went with the 6 pistons and put them on this with front coil overs and tubular a-arms. The front looks good, the rear... will be a winter project.
01-13-2020, 08:19 AM
hahahaha , also lol @ 2037.
