Early Stages of Single Turbo LS1 Build
 

In the very beginning stages of a single turbo LS1 build. I was very fortunate in having won an online competition by Comp Turbos. The challenge was on Instagram, they posted a black silhouette of a vehicle and our job was to choose the correct vehicle and then pick a RWHP #. The closest to the real dyno numbers win’s a free comp turbo of your choice to fit whatever application you want it for. I choose a Toyota Supra 2jze with 976rwhp. It made 1005rwhp on its first pull. And I was the closest to the end numbers. Justin from CompTurbos has been working with me in getting a turbine that’s best going to fit my application without closing any future doors for a larger build to run higher boost.

So far it’s looking as such, a CT3 67mm Ball Bearing turbine & housing with a paired external WG. Mind you this is not my first time around a SBC build. About 1.5 years ago I built up a 383 Lt1 with the help of ElliotsPort works, a wild not mild 232/240 110. LSA cam with an eagle rotating assembly… Yada Yada Yada. Anyway sold the car and moved up to a LS1. My goal was going to be a GenTTR twin kit over the next 2 years. Now I’ve won the turbo this my goal.. I know everyone runs 317’s with FI but I honestly feel like a set of Lloyd heads will suffice to only running 7-8lbs.

Stock bottom end LS1, single turbo with Lloyd heads. I trust Lloyd, his work is great for a non CNC port. Anyway I’m thinking this… LE2 heads, a custom grind hydraulic (I’m not convinced a solid roller is conducive for this build) turbo cam Lloyd will spec up along with a big front mount setup, LS6 Intake mani and an 85mm TB, meth cooled on pump gas. Obviously all the little goodies in between, rockers, studs, springs, retainers, fuel pumps, oil feed lines, 60lb injectors, etc. I’m familiar with the Walbro 255LPH, with this setup are two necessary also in tank… or no?

My Question to you guys is where is the best mounting position is from your experience, NO rear mount. Im not dealing with the oil feed problems and all the other BS involved. Im thinking either left of the tranny by fabbing the strut to fit a mount somewhat like the GenTTr kit does, without re-locating the AC or ABS that would be ideal or possibly front of the motor by relocating the stock radiator. There’s going to have to be some custom fab for the intercooler and the piping and what not. On top of that I know the 6.0L truck manis are ideal for front mount turbo setups not looking to break the bank so long as the diameters are matched and ported, there cheap and easy to work with, I know that. So that route is looking pretty likely.

Currently as the car sits it has some work… Wires & Plugs, Longtubes, Exhaust, Stage 2 Clutch, Short Throw, Eaton Posi Unit paired to GM High Pro 4.10s, Bosch Oil System, Rapid MotorSports tune. The 4.10s will be the first to go, probably throw in a set of 3.73’s or even stock 3.42’s. Some serious questions I have would be the fuel rail? Am I going to be looking at entirely new fuel system or will stock be okay with the fatty injectors?

After all is said and done I would like to see the car make 540-600rwhp on a stock block running low boost (7-8lbs) with a meth cooled setup. Long term goal would be as such, getting a stronger 12 bolt main, Weisco or an alternative set of piston’s to drop the compression and be able to run a higher boost, maybe bring the overall bore to a 348 or so.. I’m also going to avoid any stroker build up, Im not looking for a drag hog. Just a street sleeper Ls1, upon first glance it’d appear as a normal z28 but when under WOT a turbo beast. I do not need a 9 second car.. I’d be very happy with a 10.99 with a 1.7 second - 60 foot and 132 ET mph.

Let me end the post by going ahead and stating if anyone has negative or degrading comments like all you trolls out there do… Just stop now. This is my build this is going to be my unique setup. You can throw some advice around and problems you ran into and what worked best from what you know, but when it comes to why are you doing this, why do you want that yada yada yada keep it to yourself. This is for serious commentary not for emotional bouts of acclaimed pseudo knowledge. As I get more details from Comp I will update the post, they are spec’ing me my own turbo based on what I want, the turbo and housing is all going to be specific to my setup and that’s that.

I need productive discussion, please send your feedback, thoughts, advice etc. I would to love to hear what some of you guys have to say and suggest. From parts, setups, fab’s, etc. Let me know!

:judge:

First off, that Turbo is too small. No need to port the heads for your power goals, the 241s will be fine. No need for aftermarlet rockers. Go with some PAC 1218 Springs or for more comfort the BTR .660" Springs. Do 80lb injectors while you can, just a little more money. Dual 255s are needed as well; the stock rails are good to 700+hp. If you want A/C check out Huron Speeds' new A/C system.Otherwise a Truck Manifold on the Driver side, and a C6 Corvette LS2 manifold on the Passenger side.

First off thanks for the input. I checked out the BTR's that entire set the sell looks like a good option. I figured the dual wals would be a must. Do you think it would be worth having a low lift cam made for a turbo would be a good route to take? I have another question too, I know a lot of guys go with SCT and Diablo or an open source tune. I'm in Pittsburgh, where or who would be the best tuner within towing distance that works with one of those three options. I'm surprised more guys havent voiced their thoughts so far but thanks again.

dude do not get that tiny turbo unless its going on a geo metro. That's crazy. Did you say its for a 5.7 v8? Did they recommend a 67mm turbo to you? You need at least a 75mm turbine wheel. If you can choose any thing get what i have. A ct5 88mm comp wheel 88/94 turbine wheel. They can make it with a ct43 comp cover if your tight on space. There is pretty much no lag so don't worry about that. That will support you with a stock engine or you build something and want to run 20psi. Don't be scared on "larger" turbos. A 348 ls1 flow a lot of air.

As far as the setup. You can do a driver side truck manifold and a c6 vette manifold on the pass side this way you can keep ac,abs. Mine is in front of the balncer but i had to stand up my radiator. If i could do it all over again i would have left the radiator and fans alone. Relocate the battery to the rear and put the turbo where the battery was. Simple and cheap. Hope that helps you. I hope you don't take the turbo stuff like im being a Dick,i speak from experience. Ive had a 67mm, 78mm,80mm,and not 88mm. Wish i had skipped the 3 others.

Regardless of what you say you'll be happy or content with you will get the disease we all have that have been down this road. Its never satisfying, more power needed/wanted, my only limits are the limits of my wallet disease lol.

honestly at this point, the FI section on this website is so saturated with different setups and great information, I wouldn't even post until you have read for a few weeks.
LS1 is NOTHING like an lt1, NOTHING.

This is how my turbo setup is. Cooling system is untouched, and I have A/C blowing cold on these 95 degree days. It may be difficult to put a real big turbo there without further modification, but it'll be no issue for the power levels and beyond you're looking at.

http://i198.photobucket.com/albums/a...ps6175a77f.jpg

My power goals were similar to yours when I started out with my build. I ended up keeping the stock LS1 short block and decided to run e85 for fuel.

LS1 short block, ARP head studs, LS9 head gaskets, stock heads with Patriot dual springs, Katech high volume oil pump + LS2 timing chain, LS6 cam, stock LS6 intake manifold with ported stock throttle body, aftermarket fuel rails, 80lb injectors, Aeromotive A1000 boost referenced FPR, dual in tank Walbro's, Turbonetics T78 1.15 AR 68mm turbine, etc.

I put down 641/638 on 16 PSI through a 4L80e on an conservative tune. 1200 miles on the setup now, no issues.

This for sure.

I figured there would be those who would be saying to get a bigger turbine. And I think its humorous someone already assumed that because I did a lt1 build I dont know the difference between the two. Anyway I was looking more for a starting ground than anything definite, your response in particular is what I was waiting on. Some one who had done almost the same build, the results, difficulties you ran into what not. I would be more than satisfied with 530-550rwhp on a safe tune. Its not going to be a DD either way. Along with a few other obvious things life a driveshaft and different gears I just wanted an idea of what others are using to meet their goals. In your opinion do you think the aftermarket rails were necessary or just extra incentive?

Also the contest rules stipulated that you had a choice of ct2, ct3, ct4 and that was it. I ended up with the CT4, TriPlex Ceramic Ball Bearing 6767. Oil cooled, anti surge, 4inch inlet, 2.5 inch outlet etc. For free... I am not going to complain, Im going to make what power I can with it and that'll be it, Im not going crazy here just want a very quick streetable stock block ls1.

What wastegate and bov did you go with? And I dont believe any has put any input on a solid FI tuner for our motors on the east coast.. I want the best tune money can so long as its with in towing distance. One last thing has any done this and kept the T56..?

@evo462 Looks like a tial mounted up there by the oil cap. The intake mani looks great in red too.

No not all I appreciate the input more than anything.. If I were investing in my own choice of turbo yeah I would definitely going a lot bigger along with either 317's or made LLoyds Le3's and a bigger cam. This situation just kind of fell into my lap so I am going to run with it and make what I can I out of it while still retaining the stock bottom end, gives me a lot of room to move in the future. I really do appreciate the input though.

Maybe I could have gotten away with stock rails, but it was the easiest way I could think of to mount/incorporate the boost referenced FPR into the fuel system. Plus I do plan to make more power on a different engine someday and the cost was relatively low. I run stock lines from the tank to the rails though.

I'm still running the stock drive shaft. Maybe it'll break, I dunno...I don't do a lot of hard launches and if you're only looking for 530-550 RWHP maybe you can spend that money elsewhere.

I'd sell that turbo...yes you got it for free, but you can sell it and use the cash for a turbo that'll better fit your setup. That is a small turbo for a single. You could get a TC78 or something for $650-700 and it'll more than meet your goals.

I'm using a Tial 50mm BOV and Tial 44mm wastegate. The BOV flange is welded to the end tank on my intercooler.

My car was originally a T56, but what it came down to for me was this...T56's start breaking when you add a bunch of power to them. Maybe a built one will last, but they're expensive. And you'll never shift one as fast as an auto shifts, and maybe boost falls off some during shifts. My thought was why spend all this money and be hindered by the transmission. Yes lots of people are running manual transmissions with turbos, but I sold my T56 and LS7 clutch and funded a good part of a 4L80e swap. Doing the transmission swap added a good amount of extra work to my build though.

That turbo would be instant spool. Like 1800 rpm lol....

Even with the TC78 the choke point would be the 68mm exducer on the turbine, which the Comps excuder on the turbine is only 1mm smaller. I'm almost certain the Comp would be more efficent until it maxes out the compressor just because the TC78 is such a mismatched turbo.

Sounds like your dead set on running this turbo, so give it a shot! Never hurts to try, and it looks like its a t4/3" dp so you could always upgrade in the future to a PT7675 or a Turbonetics 7675. It would be nice to start with something properly sized from the beginning though.

Plenty of people have made 700-800 rwhp on TC78's. Yes the 68mm turbine may on the smaller side but it'll far exceed his power goals and have great street manners. Mine shows no signs up being "choked" even running e85 to 6100 RPM's making somewhere between 750 and 800 at the motor.

Regardless of whether I end up selling it and going with another or keeping it my questions still stand as this...

Is it worth putting a small custom ground HYD cam in it or no?

And the tune? Who is the preferred EAST coast tuner for FI or NA LS's ???

As Evo462 stated for my application the Ct6767 is looking positive, room to mount it with out many issues and it will make the power I need out of the car without much issue.. On pump gas, its what Im looking for.

Curious LT1ray. I have a stage 2 clutch now, how are you liking the monster 3 with the boost and the m6? Im assuming T56? And no issues with the rear end yet? Stock driveshaft, seems to be mixed emotions on the forum with the Stock vs Lpe's shaft..

I'm at 530rwhp and m6 factory T56 stock driveshaft and monster level 3 kit. Clutch is awesome DerrickB343

Stock rear also.

Yes get with Martin @ Tick for a cam and spring kit. East coast I'd say Slowhawk. Or see if Phil Thomas would tune you.

There are things that can be done with the camshaft to help a under sized turbine wheel perform better, and not fall off up top as bad as it would had these steps not been taking when designing the camshaft.