87Aerocoupe

Hey folks I recently brought a 97 SS, m6 and 3.42 rear from a member here Sick 97 SS (thanks man) and I need to replace most of the exhaust. The car has Pacesetter LTs that are rusted thru as is the intermediate pipe, anyway I already have the ebay stainless steel LTs and y-pipe and I have a new intermediate pipe for it and I will be wrapping the entire exhaust but I also have a brand new Turbonetics 62-1 p trim .96 a/r turbo from a previous project and I have a set of 42# Racetronics injectors as well so I've decided to build my own rear mount turbo setup. I only plan to run 7# of intercooled boost with water/meth for now until I get the funds together to build my new all forged 383. So I've been doing a lot of reading here so I know I need an oil return pump , lines (feed and return), check valves, 340lph intank fuel pump and 2.5" cold side piping. I'm also going to get a CX Racing fmic and a pcm4less mail order tune to start with am I forgetting anything??? Everything else is stock except for "hotcam valve springs and roller rockers" can this setup make 400 rwhp/ 430 rwtq??
Oh and I'm building an 8.8 rear for it so that will be solid.

97WS6SCharged

I would look at a stiffer dual spring instead of the LT4 springs you have but other than that you shouldn't have any issue pushing 400 or so with that setup.

Mr99SS

IF IT DIDNT MAKE 400 rwhp id burn it .... seriously u should do that easy ... I made 330 rwhp with my ls1 no tune ... always remember its in the combo an tune. I ran 13.50's with an 06 tbss with 4k miles with a cold air and vector tune.. 4,800lbs an I weigh 220 so do the math

87Aerocoupe

Thanks guys the valve springs and roller rockers were on the car when I got it so do you think they still need to be changed now? I also have most of the parts for a nice 383 (forged Cola crank, SRP -16cc dished pistons, spare block, LE3 heads, 58mm Holley tb) just need this turbo setup to last about a year or two so I can get the money together to finish the new 383. I'll start buying patrs at tax return time and hopefully have everything up and running by the summer.

97WS6SCharged

The LT4 springs barely maintain enough pressure to control the valves on a NA engine. Add boost and they become questionable.

Also, if you're planning to run a turbo on that 383 then you may want to look into another piston. -16cc with a stock head will yield over 10:1 compression.

87Aerocoupe

What springs would you guys recommend I get and install, what about the Crane dual spring kit for the LT1s, I think I have a new set of those's in my stash of parts? I forgot to mention the car has 133,560 miles if that makes any difference, thanks for all of the advice as well. Also what are you guys using for your cold side piping steel or aluminum, the reason I'm asking is because I want to run 2.5" aluminum tubing from the turbo to the intercooler to the maf/tb elbow to save weight? I was looking through the parts I have from the other project and I have a box full of 2.5" aluminum intercooler piping with silicone connectors and stainless tbolt clamps!!!!!! Championship, even less money I'll have to spend on this project.

87Aerocoupe

WS6SCharged when I build the 383 with those pistons I believe the scr works out to 10.2:1 which is lower than stock and since everything in that engine will be forged and I only want to make around 550-600 rwhp with it I shouldn't need more than 12#-15# of boost to achieve that should I? I should be able to run that low amount of boost with that compression, I have another 383 sbc with the same scr with a Procharger making 13# of boost and it makes 700 rwhp on pumpgas though it's in a blow thru carb setup.

97WS6SCharged

Comp's 987 springs are a good low budget choice that would work well with low boost and the stock cam.

Not sure about running aluminum pipe under the car. I would guess it would work fine as long as it's a good thick walled pipe that can take a rock hit or whatever without busting. I've never run a rear mounted turbo so grain of salt on that advice.

I wouldn't attempt that much boost with pump gas unless it was E85. I run 9.2:1 on my 383 LT motor and 9.4:1 on my 408 LS car.

87Aerocoupe

Thanks WS6SCharged there's a guy selling a new set of 987 springs retainers etc so I guess I'll pick them up. Would it be worth it to put in screw in studs and guideplates while I'm changing the springs? As for the aluminum piping since I already have it I'll use it and if I have any issues I can always change it later, I'm just worried about rust inside the pipes if I use mild steel.

97WS6SCharged

The stock rocker studs are screwed in. I wouldn't change them unless you're going to upgrade the rockers to 7/16 studs. As far as guide plates if you have self aligning rocker arms they aren't needed however if you do install a set make sure you install a set of hardened pushrods.

87Aerocoupe

Thanks WS6 I brought the 987 springs, locators, retainers and locks and I'm debating installing a hotcam I have laying around along with the springs, what do you think of adding the cam with the turbo? And I also have a set of guidplates and Comp hardened pushrods in my stash of LT1 parts, that's why I was asking about installing them along with the springs.

97WS6SCharged

The hotcam is very tame and usually works well with boosted apps. I wouldn't hesitate to run one in a stock build. You'll probably pick up 30-40 hp over the stock cam with low boost.

You need to be careful using guide plates with SA rockers. The plates can cause the tabs on the rockers to contact the valve tips if they change the alignment too much. I'd use one or the other.

87Aerocoupe

Thanks 97WS6 if I install the guideplates I'll switch to nsa rockers like maybe some scorpion 1.6's and thanks for the advise on the cam I think I will go ahead and install it.