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St. Jude's Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
NEED ADVICE on Turbo LS1 build
I’m in the process of building a mid-engine LS1 car with a Porsche transmission. I am thinking about running twin turbos on it or possibly a single turbo. Only want to make 500-550hp out of it. That’s plenty fast and I don’t want to have to beef up the internals of the motor or transmission right now. My question is can I run a set of LS truck exhaust manifolds upside down and left / right reversed, facing the rear with turbos bolted right to the manifolds? I am thinking upgrade the intake to LSX or at least LS6. Was going to also buy some heads but I’m thinking the turbos should easily be able to make 500-550hp without changing heads or cam change.
I know very little about all this but I learn quickly from experience and (usually) tearing things apart. Here’s a couple pics. The motor and trans are not mounted yet. Have the harness out getting repinned and rewired currently.
Stock heads will easily reach that.
LS6 intake will be good no need for the Fast LSX Intake.
YES the truck manifolds will work just fine and make great power.
Looks like a very fun project keep us posted twins will looks better with that setup in my opinion What engine in it now?
Twin 5x will work great and spool very fast if you're only looking for 550rwhp or maybe single 70mm
St. Jude's Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
Awesome! I’ve got the harness out being repinned. Fuel tanks are supposed to come in tomorrow. I’ll be running an external fuel pump. Any recommendations for a reliable pump that isn’t noisy to the point of ridiculous and can supply enough fuel for 500-600hp without a problem? I wanted to go with an in-tank pump setup but I found a pair of nice aluminum tanks which will give me 24 gallons total with level sender and filler neck.
Going to look for a set of truck manifolds online tonight. It has LS7 stock manifolds on it which I guess I’ll put for sale since they seem to be desireable cheap upgrades for the LS motors.
St. Jude's Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
Had to order a new flywheel, the adapter kit from Kennedy engineering sent me a flywheel for an LSA motor so of course nothing goes easythe first time!
Anyone used these headers for turbos? Price seems really cheap. Want to run them upside down so the turbos sit above/behind the motor above the transmission with exhaust straight out from there. Any recommendations on injectors and turbos / best bang for the buck? I’m only wanting to make 500-600hp. Have a Bosch fuel pump should be more than enough for it.
St. Jude's Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
I’m on the fence of upgrading the internals while the motor is out. I’ve talked to a lot of guys and hear about 50/50. I’m thinking I will be happy with around 500rwhp. A bone stock LS1 with 28k on the motor out of a C5 Vette. I’m thinking I dont need springs or pushrods if it’s a stock cam. If I keep boost down with big intercoolers with lots of airflow to them and unobstructed short large diameter exhaust.
What do you guys think? Could have upgraded head gaskets, head bolts, springs, pushrods, main bolts done for a pretty reasonable cost - but is it worth the money? The Porsche transmission I’m using is really only good for about 600hp with limited abuse.... so 500rwhp would be ideal for that reason as well.
If the motor is out and you want peace of mind I don't see why you wouldn't upgrade the valvesprings, pushrods and trunion bearings. They aren't necessarily known to fail but they are all cheap insurance to keep your motor happy.
I’m on the fence of upgrading the internals while the motor is out. I’ve talked to a lot of guys and hear about 50/50. I’m thinking I will be happy with around 500rwhp. A bone stock LS1 with 28k on the motor out of a C5 Vette. I’m thinking I dont need springs or pushrods if it’s a stock cam. If I keep boost down with big intercoolers with lots of airflow to them and unobstructed short large diameter exhaust.
What do you guys think? Could have upgraded head gaskets, head bolts, springs, pushrods, main bolts done for a pretty reasonable cost - but is it worth the money? The Porsche transmission I’m using is really only good for about 600hp with limited abuse.... so 500rwhp would be ideal for that reason as well.
if you are only going for 500 hp you clearly don't need turbos drop a crate ls3 at 525 for example. way too much cost for no HP
I wouldn't even think of doing turbos for much less than 700 and the stock motor is fine at that level
if you want to boost it more like 18 or so, consider a better block and internals but then you are up at 900 or so up and it will live just fine
run e85 if you can and the stocker will avoid detonation and live a happy life also you don't need intercoolers with it which simplifies things
I'd throw a modded ls7 with 600 hp in there and be done
if you turbo, set goals higher than that or honestly don't bother. I have plenty of truck manifolds if you need them
fyi I have a build 4.8 turbo short block with gen4 crank and rods and wiseco forged pistons
fresh from machine shop this little thumper has a thick block and will handle quite a bit more than the weaker ls6 block, but with the associated weight penalty
St. Jude's Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
Originally Posted by Rkreigh
if you are only going for 500 hp you clearly don't need turbos drop a crate ls3 at 525 for example. way too much cost for no HP
I wouldn't even think of doing turbos for much less than 700 and the stock motor is fine at that level
if you want to boost it more like 18 or so, consider a better block and internals but then you are up at 900 or so up and it will live just fine
run e85 if you can and the stocker will avoid detonation and live a happy life also you don't need intercoolers with it which simplifies things
I'd throw a modded ls7 with 600 hp in there and be done
if you turbo, set goals higher than that or honestly don't bother. I have plenty of truck manifolds if you need them
fyi I have a build 4.8 turbo short block with gen4 crank and rods and wiseco forged pistons
fresh from machine shop this little thumper has a thick block and will handle quite a bit more than the weaker ls6 block, but with the associated weight penalty
pm me if you need it, selling cheap
Thanks but I already have the LS1 and the $3000 adapter and clutch kit for the Porsche 6 speed transmission. For that reason I will stay with what I’ve already got and have the harness reprogrammed/rewired already. Also had to pay like $500 for the damn pedal with module because the LS1 didnt have the module in the main computer.
After talking to many people with lots of experience 500rwhp will be no problem without doing any internals. Some guys are making around 600rwhp on stock internals with a cam and intake. Of course sticky tires / slicks would most likely be too much on it but I’m building the car to be fast but not racing it. Just want to be able to hit high speeds when I feel like it. Also want the turbine sound to be very noticeable so I will likely run 3” out the back which will be only a foot or two from the turbos.
LS7 motors are great but, from experience, the components are much more expensive. I figure I will run twin turbos on this LS1 and if it blows up I will do an LS2 or LS3 at that point since the bolt patterns should be the same for the bell housing. The goal is to not waste money so I hope the LS1 makes 500rwhp give or take a few with reliability and not beating it to hell.
St. Jude's Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
Well it's been a while but I have the LS1 installed, the trans also. The custom made high-hp axles in. AC. Power Steering. Headers on. Harness on. Problem is it will not start! It did fire over a few times and die immediately. We can get it to run (sort of) with brake cleaner in the throttle body. So it must be getting spark. The tanks have new 93 octane in them. The Corvette fuel filter/regulator is in place. I thought maybe the injectors were seized up since the motor is a 2004 with 13k original miles and hasn't run in many many years. Changed those out and nothing. The holley pump primes when I turn the ignition on. I even tried running a constant power to the pump as a last ditch effort in case it was cutting power once it turned over - nothing. The harness was done by a company in Melbourne FL that's know for doing excellent harness rewiring on LS's. I sent the PCM back one more time to have the tuner check and see if the VATS was shut off for sure and he confirmed it was.
Only thing he wasn't sure about was that I have the drive-by-wire pedal and his cars usually have the manual cable throttle bodies so he wasn't sure if that could be an issue. We did have to extend the harness from the module to the pedal but it is plugged in and you can hear the throttle butterfly moving so I think it's good.
I'm about a few days away from trashing the stock stuff and buying the Holley Terminator X Max system with harness. I do have the upgraded injectors but they aren't installed because he left the tune stock so I could get it running and hook up the cooling lines and run the turbo plumbing, charge the A/C, fill the power steering, etc.
ANYONE with some advice I'd be eternally grateful. I'm thinking maybe a ground somewhere? Maybe a sensor is bad keeping it from running? Going to pull the fuel rails off tomorrow and put cups under each injector and see if they are squirting when I crank it.
St. Jude's Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
Originally Posted by ascastil
Oh **** you weren't messing around. Nice car.
Do I see 2 coilovers on one corner of the car?
Thanks!
yea it has the same exact setup as the original car of 4 coilovers in the back and two in the front. Six total. Not sure why it’s that way but I stuck with it because it definitely works
07-28-2018, 08:50 PM
NEED ADVICE on Turbo LS1 build
