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So it's official: I've had enough of the boring Pontiac 400 and decided to go LS like the rest of the world. After having a couple of Buick T-Types I will naturally go turbo. Since my last Buick was running about 480 crank hp I figure 600-650hp should keep me entertained … for now. I've picked up a non-vvt LC9 w/ TBSS intake and a 2006 4l80E, both chosen because they were low-mileage. I do have a couple of questions.
The engine came without a harness. To my knowledge the only Gen4 LS to run a 4L80e without VVT would have been a 4.8 Chevy Express -- would this be the best OEM PCM/TCM/harness to grab if I can find one?
What 4L80e dipstick/tube fits the A-body chassis?
I've noticed that most guys on here are shooting for max hp builds and running 9-second quarters. I'm more into mountain road twisties and a fun street car, this is a restomod with full interior, AC, power steering, etc. Will probably hit the track once and get booted for no rollbar. Probably I could make 600hp naturally aspirated, but I loved the 2500-6000rpm midrange power of a Grand National and would like to build something similar.
With this in mind, what are some suggestions for a cam, converter, & turbo? Currently I'm thinking Triple 12, 3000 stall, & 70-76mm. Also, in case I run out of time/money for the turbo setup, what would be a fun cam to run for a season and then turbo next winter without changing it?
And finally, is intercooling necessary at this power level or not?
Cool car and project. The original (Not V2) Tick Stage 1 turbo cam would most likely work well non-turbo and then shine with a 76 or 78mm turbo. Performance Automatic makes a locking tranny dipstick for 4L80's in Chevelles so maybe that's something to look at. I'm not sure that you need to look too hard for a computer. Any newer drive by wire throttle body LSx PCM should work whether it's out of a 2006 van or 2008 Silverado or whatever. Do your homework as you'll want to make it easier on yourself matching up 58x reluctor / DBW TB with the right PCM.
As far as a Converter goes, give Circle D or someone similar a call. A TransGo HD2 Shift kit and a good converter and you should be good at your stated power goal. Aeromotive has return style gas tanks for Chevelles if you go that route with your build although the pump is small for your goals.
Do a search for GTO within this section as there are a few people who have LS swapped these cars with success and the answers you seek may be in their threads. Good luck!
We give helpful suggestions to idiots. You seem to have a reasonable plan, and google search skills. At this point, just build your ride and have fun. If you manage to totally **** it up, which I doubt, come back.
LOL, ok. I know the swap itself is common and there are some great threads here on it. Couldn't find "canyon carving turbo 5.3 combo" on a search. Probly should have posted in the turbo section.
Honestly have you looked into the terminator x setup? Since you're going turbo it has boost control built right in and can handle pretty much any combination you can think of. As a matter of fact I'd just got with holley mounts and pan. The holley pan has provisions for oil drain too. Hard to beat what they offer.
I'd like to also toss out that summit has ls cams too and seem to be pretty decent power wise. There should be a couple of threads about them on here.
Honestly have you looked into the terminator x setup? Since you're going turbo it has boost control built right in and can handle pretty much any combination you can think of. As a matter of fact I'd just got with holley mounts and pan. The holley pan has provisions for oil drain too. Hard to beat what they offer.
I'd like to also toss out that summit has ls cams too and seem to be pretty decent power wise. There should be a couple of threads about them on here.
I got the holley 302-3 pan but just where it sits in my 72 el camino you cannot use the oil drains anyway. I still went with it knowing that (wanted to see for myself). I think the only difference in the -2 -3 pans are the 2 built in oil drain bungs.
Honestly have you looked into the terminator x setup? Since you're going turbo it has boost control built right in and can handle pretty much any combination you can think of. As a matter of fact I'd just got with holley mounts and pan. The holley pan has provisions for oil drain too. Hard to beat what they offer.
I'd like to also toss out that summit has ls cams too and seem to be pretty decent power wise. There should be a couple of threads about them on here.
I'm a little gun-shy of Holley right now, after having 2/2 Sniper units fail on me. I did order their pan though, and their engine mounts and crossmember seem to be the best-researched for the 4L80E fitment. Will probably order those.
Looking seriously at that Summit turbo cam, or else the Trackmax/Sloppy Stage 2 turbo cam.
Hi there, beautiful car. We tell customers considering LS builds, but concerned about originality to put the original stuff up in the rafters and it's always there if you ever want to go back. You never will At any rate, we'd recommend the Summit Pro LS Stage 2 turbo cam SUM-8706. It makes great power with our without a turbo. The intake lobe and the valve events are identical to our N/A cam SUM-8707. The exhaust opening point is identical too. The only event that changes is pulling the exhaust closing point back from 3 atdc to 2 degrees btdc. This change reduces overlap 5 degrees. Exhaust closing is the least critical of the 4 events naturally aspirated....so it's a little down from the N/A cam, but not much and you won't miss it because everything else is optimized. It's going to match the converter and the weight of the car and the lobes are stable to over 7k rpm with a TFS-16918-16 .600 lift beehive. If you want to swap to a Dorman LS2 intake, you could run GTO "valve covers" for the cool factor. Finally, we have guys running bottom 9's already with boost...so it's more than capable later on as you develop the car. Let us know any questions you may have, but the cam will make you happy.
Hi there, beautiful car. We tell customers considering LS builds, but concerned about originality to put the original stuff up in the rafters and it's always there if you ever want to go back. You never will
Exactly...Once you go LS you'll never look back...
So regarding the pcm/tcm/harness -- will that 4.8 Express/Savana van be the best setup to get? Or just any 08-09 Gen4 computers/harness?
E38 pcm, from 07-13 trucks, can be used with a oem T42 transmission controller, a few vendors have a swap harness that includes the tcm pre-programmed
if you goal is only in the 650hp range, a 6l80 is also an option had good luck with mine around that power level for a year and a half/40k miles
At any rate, we'd recommend the Summit Pro LS Stage 2 turbo cam SUM-8706. It makes great power with our without a turbo. The intake lobe and the valve events are identical to our N/A cam SUM-8707. The exhaust opening point is identical too. The only event that changes is pulling the exhaust closing point back from 3 atdc to 2 degrees btdc. This change reduces overlap 5 degrees. Exhaust closing is the least critical of the 4 events naturally aspirated....so it's a little down from the N/A cam, but not much and you won't miss it because everything else is optimized. It's going to match the converter and the weight of the car and the lobes are stable to over 7k rpm with a TFS-16918-16 .600 lift beehive.
Besides being $20 cheaper ( ), why do you suggest the 8706 over the TrackMax?
I'm pretty specific that I don't want to lose bottom end power for squirting out of the corners, waiting for boost to hit. Maybe a 72mm turbo would work better than a 76? And even possibly the Ghost Cam over the Stage 2?
Besides being $20 cheaper ( ), why do you suggest the 8706 over the TrackMax?
I'm pretty specific that I don't want to lose bottom end power for squirting out of the corners, waiting for boost to hit. Maybe a 72mm turbo would work better than a 76? And even possibly the Ghost Cam over the Stage 2?
If you compare seat timing at .006 (advertised duration) the SS2 or that particular TrackMax cam has duration of 283/286. The SUM-8706 Pro LS stage 2 Turbo cam has shorter seat timing with advertised duration of 275/283. At .050, SUM-8706 has nearly matches the SS2 and surpasses it at higher lift points. Valvetrain stability is very good at high rpm with a decent spring pack.
The .050 timing numbers for the SS2 are 6 I/O, 42 I/C, 51 E/O, and -1 ec for a total of 5 degrees overlap. The SUM-8706 events are 4 I/O (slightly smoother idle quality), 42 I/C (effectively the same as the SS2 at that point *only), 52 E/O (slightly better spool), and -2 E/C for a net of 2 degrees of overlap. Mostly what you are seeing with the SUM-8706 is more area under the curve without causing valvetrain instability. The next thing is the lower overlap reduces reversion as turbine inlet pressure rises. This reduces heat build up in the cylinder that can take out rings and pistons...and generally makes more power because you're pulling fresh air/fuel in rather than trying to burn exhausted air.
Stage 1 Ghost cam is a good choice as well with a intake closing point of 43 degrees and -3 overlap...it would have bit smoother idle and still haul the mail. Here's a video on it if you would like to learn more
Besides being $20 cheaper ( ), why do you suggest the 8706 over the TrackMax?
I'm pretty specific that I don't want to lose bottom end power for squirting out of the corners, waiting for boost to hit. Maybe a 72mm turbo would work better than a 76? And even possibly the Ghost Cam over the Stage 2?
My vote is for the ghost cam. I'm partial to it because i have one and like it. My car drives like stock and has good bottom end tq. I have a set of GTO intake covers I'll sell if you decide you want some.
I have 2 different lingefelter cams (I'm very partial to their cams for driveability.....wide LSA like factory GM cams). If you want ultimate driveabilty, great low-end, and still make decent power, check out the GT2-3. I have this in my C10 and I absolutely love it. It's very mild, but it seems that's right up your alley with this build. In my GTO I have the GT11. A bit less mild, but still not crazy.....the 118 LSA really helps. Honestly though, for your build, I think the GT2-3 is the ticket. I really love that cam. It's so nice, I'm actually considering swapping it into my GTO.
My vote is for the ghost cam. I'm partial to it because i have one and like it. My car drives like stock and has good bottom end tq. I have a set of GTO intake covers I'll sell if you decide you want some.
I too like the Ghost cam very much. I am currently running it in my 67 Cougar, 5.3L, NA. There was zero downside to this cam compared to the GM ASA cam that I replaced.
As for GTO builds, check out mine and also Tom's 70 GTO build. They are built as almost twins.
I also strongly recommend the Holley swap components (Tom's car was used as the development vehicle). Holley also makes a simple single turbo cast log kit that will fit A-bodies very well and will be perfect for the power level that you're after. The turbo placement will be similar to a GN, so you should feel right at home.
The 5.3 is alive and well. Car made 340 rwhp @5900 on a chassis dyno, and just completed a 1700-mile round trip averaging 18mpg. I expected better. Decent power up top but lacks the bottom end of the Pontiac 400. I have a 9.5" lockup converter that footbrakes to about 3000rpm and the car won't spin the tires no matter what. I had it restalled from 3400--it was a tire-smoking beast but I didnt like the driveability. Also is pretty gutless climbing mountain passes in normal driving, TC locked up at 2000-2500rpm.
Ideally I'd like to pick a turbo that will spool a little at that rpm so I don't need to downshift. Either that, or I need to buck up to a 6.2 to suit the personality of the car. Hard to decide .... but a turbo should be cheaper and power potential unlimited. Still sticking with Plan A for now ...
10-02-2019, 09:44 PM
1970 Turbo GTO 
At any rate, we'd recommend the Summit Pro LS Stage 2 turbo cam SUM-8706. It makes great power with our without a turbo. The intake lobe and the valve events are identical to our N/A cam SUM-8707. The exhaust opening point is identical too. The only event that changes is pulling the exhaust closing point back from 3 atdc to 2 degrees btdc. This change reduces overlap 5 degrees. Exhaust closing is the least critical of the 4 events naturally aspirated....so it's a little down from the N/A cam, but not much and you won't miss it because everything else is optimized. It's going to match the converter and the weight of the car and the lobes are stable to over 7k rpm with a TFS-16918-16 .600 lift beehive. If you want to swap to a Dorman LS2 intake, you could run GTO "valve covers" for the cool factor. Finally, we have guys running bottom 9's already with boost...so it's more than capable later on as you develop the car. Let us know any questions you may have, but the cam will make you happy. 
