lcvette

iTrader: (3)

Hey all,

(I Already tried SEARCH! its not bringing up any information with my query terms and I tried a BUNCH)

I am starting my build again 1996 fully built 355 LT4 corvette, previously a PT74GTS. I think I will convert to twins this go around to free up some room in the front of the car and reinstall the A/C (I am getting too old for the heat...lol). I have changed the configuration under the car to fit twins and it makes plumbing MUCH easier to go manifold/turbo/downpipe, then the crossover and fitting a bigger turbo (especially in a C4 corvette). Also the use of larger downpipes is made as simple as it can be and the heat is towards the bottom rear of the engine compartment rather then an inch from my fiberglass hood.

My question is regarding the turbo selection. here is the build so far if you are familiar with the old style chevy motors..lol

355ci forged bottom end (8.5scr)
224/224 .600 .600 115lsa cam
AFR 227 competition series heads (flow 305cfm peak)
AFR Hydra rev kit
Caddy Racing lifters
Shaft mount rockers 1.7
58mm Holley twin bore throttle body
Edelbrock air gap LT4 manifold matched to obnoxiously large heads
DFI Gen 7 and w/ dual synch dizzy for full sequential, WB, Knock module, 3bar
Built Fuel system (160lber's, twin A1000's planning on running E85 mainly)
custom 321 SS manifolds will be built
twin Tial 38mm gates external
Tial 50mm BOV

what is left to make a decision on and where I am turning to you guys is on the turbos and possibly some input from those running water to air intercoolers on street driven cars.

Turbos, obviously I know the GT3582R's will support some very nice power but I am looking at boost response for you 346 guys mainly as well as length of time from boost start to peak boost and what those peak values are and where they fall in the RPM band.

I figured I would go with the .82A/R housings since I set the car up to be a high revver ~6500-7000 I figure there abouts.

Intercooler, I like the idea of the water to air intercoolers for the track days and being able to ice down a resevoir to get better IAT's even in the heat of summer without resorting to nitrous. sure does give a nice edge over the competition. but I wonder how well it would do with an adequately sized heat exchanger for daily driving and romping around town when your not dumping ice in it. has anyone run one on the street.. and do you run into saturation problems with regular sized exchangers or are LARGE ones required to keep the IC temps near ambient.

Thanks in advance guys!
Chris

veee8

iTrader: (40)

Hey, I see you are in Wilmington, my parents live over by Magnolia Greens. I am up there most every weekend. I would love to get together to check out your project sometime.

chuntington101

GT35rs should spool pretty well with .82 housings. the APS stuff is 1.06. also there are smaller housings if needed.

Chris.

lcvette

iTrader: (3)

man any time! I would love to check out your TA.. from the looks of it I would say your a bit above and beyond..lol looks like ya have a monster there!

come on up any time man I will be around this weekend.. you play golf? My brother just left for his internship this semester but he worked magnolia greens golf course and I played there about 3-4 times a week..lol

CHris

lcvette

iTrader: (3)

guess you guys all rock large singles..lol

Mike@Diablosport

iTrader: (2)

PM V-SeriesTech, he has a nice front mount air/water setup for sale.
It is fully fabricated and was used in a C5 TT making well over 800 rwhp.
It has the core, plus a large tank (3-4 gallons?) and all plumbing and pumps...

V-seriesTech

iTrader: (5)

I do, and I need to get some pictures taken of it. It is, a very nice piece. It'd be nice to keep but, could use tha cash and the extra space.

That said,..Icevette, i'm really interested in your setup on the C4. I've grown up around these cars, and my cousin, has recently had the opertunity to buy his original car, a polo green 1996 LT4 vette. We're wanting to do something drastic, sometime in our lifetime. I would LOVE to see any pictures that you might have, single or twin. Sounds like a real potential rocket, as the C4 is shaped like a wedge, and is ultra aerodynamic.

Again, would love to see some pics,...video, anything. Best wishes with the build man.

-J

lcvette

iTrader: (3)

This was the old setup, PT74GTS turbo on unported trickflows, stock LT4 cam shaft, unported LT1 intake manifold setup for the dual synch dizzy. and supporting fuel system. the car ended up making around 680rwhp on 21psi. which doesn't sound like alot for that boost level but with everything being stock and that baby camshaft and intake and heads being untouched I was pretty happy. the car acted 100% completely like stock, down to the sound and cruise you would have NEVER known it made that power. perfect smooth off idle factory torque band until you stepping into the boost.. it was an absolute pleasure to drive.

I had an oiling issue that unfortunatley wiped out the motor and the turbo all at once... had perfect pressure until I was under boost and kept having a "mis" under hard acceleration I chased this down in the ignition and fuel for weeks and finally one night I noticed after a test run and watching the laptop mainly, I glanced at the dash and saw my opil pressure rising instead of falling and tried it again and sure enough I found that under hard boost and acceleration the oil was sloshing to the back of the motor and hitting the crank weights and frothing and the pump was sucking air.. the mysterious mis.... yeah you may have guessed it.. the thrust bearing went out in the turbo and the compressor wheel began pulling into the compressor housing and it was stalling the wheel intermittently causing a boost hiccup.. by the time I figured out the builder didn't put the factory windage tray back in it was too late.. the turbo was lost and while i never spun a bearing it did score the crank from lack of pressure (stock crank so no biggie.

this time its different.. this time I did all assembly and made sure everything was perfect.

below are some pictures.. I have a short video clip with an engine shot in it but it was from a dyno day comilation vid with soem crappy music in it..

enjoy!

Dyno Video 1

V-seriesTech

iTrader: (5)

Wow, quite a story. Above all the music, you can hear the car, probably sounded pretty wild under load. Would like to see pics when your done with the twins setup. Is it going to be a top mount design, or down where the factory cats would be? Thought about laying the radiator flat but, we'd need to spend some more time looking at the car, and whats possible.

Looks real clean man(old setup).