DIGGLER

iTrader: (1)

so here i am.... making the difficult decision to move away from my great working nitrous setup and going turbo. i could have built a longblock and gone low 8's with the nitrous stuff thats in the car now, but oh well. time to screw all that up. lol
i built a 358" sbc about 8 years ago for the car. it is as follows:

Block- 4 bolt main with ARP studs
Heads- Edelbrock victor jr. 70cc chambers
Crank- Chevrolet forged/nitrided p/n 3941184
Pistons- Wiesco forged reverse dome (-11cc) .040"
Rings- Total seal
Rods- Manley 5.7 H beams
Cam- comp hydro roller 232/236 dur. .560/.586 114 +4
Intake- accel pro flow single plane with 1200cfm throttlebody

i wanted to push this one up to around the 900rwhp area before swapping parts/blocks. only thing im really concerned about is the block, really. and then the crank since its a 1053 forging. i have a 4340 crank i could use in the next block i get.

im trying to figure out what i want to do on the turbo setup right now. i have a pair of these manifolds on this engine, but im not sure i want to run them either....? lol

they have a t3 flange on them and i believe a 38mm wastegate flange. i was considering putting a pair of 66's or 70s on them. in 1990 this car had a banks twin turbo setup on it with a pair of garrett t04b's. .58 a/r turbine housing with p wheels. .50 a/r compressor housings with e wheels.

....or should i just go single?

sailtexas186548

iTrader: (2)

dam you indecisive!

is this a track only, trailered there and back car? If it is I'd do a massive single. If your trying to keep it more street-able, twins make that easier. Both make huge power, twins may cost a bit more though...

I'd run those manifolds, worst case make your own that put the turbo in the same place if they don't work and you wont have to change anything else

DIGGLER

iTrader: (1)

i know, i know..... its a 98% track only car, but it will look like a bone stock car from 50ft away. honestly the main reason i wanted to run the twins is because the car had them 20 years ago and i wanted put it back along those lines. a big single still isnt out of the question, though.

project89

iTrader: (1)

before u go buy expsensive turbos , try a set of the ebay 60-1's t3 hotsides with .8x housings and 60mm compressors. a pair will run u about 400-500 bucks. this will give u the opertunity to test out the manifolds u have to see if u need to goto t4 manifolds and turbos.

the t3 .8x housings will spool about the same as a t4 .68 which is were most guys start anyways

38mm wastegates will control boost on those manifolds prolly have a lowest boost setting of around 7-8 psi

on my iroc i have similar homeade manifolds with t3 .63 housings and 57mm compressors and i can keep boost down to around 9 psi with 2 38mm wastegates

a pair of 60's will do over 1000hp

DIGGLER

iTrader: (1)

heh heh heh i was thinking about sticking a pair of the ebays on there for awhile, but since im selling the LT1 stuff i'll have some money to play with, so to speak. i do have a masterpower 70mm .68 t4 with a trashed center in it. bearings are gone. anybody know of a good parts source for those or maybe somewhere i could send it to rebuild? or would it be worth it?

Orr89RocZ

iTrader: (20)

VS Racing deals with master power and may have repair/rebuild kits. Modular Turbo may as well as they dealt with MP turbos.

Master Power apparently is no more....they have been replaced by Magnum turbos which are about the same thing but I believe upgraded from the old wheels. I'm not 100% familiar with them but I've seen a pair of their 70's or 67's go 8.4's.

I'm curious how those manifolds will work. I'd think backpressure would certainly become an issue over 700whp. 600-700whp most say logs are maxed out. I've seen better designed logs make more power tho but nobody ever has a backpressure reading.

You could always buy a set of 10secgoal's headers over at theturboforums.net and run a big single somewhere up front. T88 should do it or one of the S400's with 80 to 83 mm wheel

Street Lethal

iTrader: (16)

Was going to go with those headers awhile back, but I didn't like the way they positioned the turbo's. This isn't my pic, but this pic is the reason why I avoided them, as the drivers side needs to be closer to the valve cover in my opinion, and I wasn't going to spend that much on them only to have to cut and braze them...

Orr89RocZ

iTrader: (20)

After having a setup with turbos up near the valve covers like that, I dont think that driver side one would clear the brake booster/master cylinder on these cars. Downpipe would be tricky to get back in there.

If you do twin setups like that, you need to get downpipe to go between cylinder tubes 5/7 and 6/8 bank to bank. Passenger side doesnt need to do between cylinders since there is room to go around it but it would be symmetrical

project89

iTrader: (1)

they should clear like that , my homebuilt headers are very similar

Orr89RocZ

iTrader: (20)

Ok that looks abit more possible. I wasnt sure.

project89

iTrader: (1)

it apears the flanges on his manifolds are in the same place as mine ( directly over the front port on each head so it should work

only thing i had to do was slightly bend my proportioning valve and bracket slightly twards the fender.

at most u can get 2.75 inch downpipe out on the driverside unless u use oval tubing then 3 inch wont be a problem

DIGGLER

iTrader: (1)

these manifolds appear to be just like the newer gale banks manifolds. the banks setup uses center inlet housings on the turbos, but i believe a standard type turbo should work as well. i have a pic of my car before i bought it with the twins on it, and i'll see if i can find it and post it up this evening. one of the main reasons i wanted to do the cast manifolds was to put the car back to the way it was back then.....-sortof. i know the banks setup has been advertised to make 1100+hp, so i was hopeful i could squeeze a little more out of them. plus they shouldnt crack/warp/leak/etc.

DIGGLER

iTrader: (1)

here is the car sometime around '98 or so, shortly before i bought it. banks manifolds with center inlet t04b's.

noboostnogo

iTrader: (4)

I hate how ls truck manifolds will support over 1000hp but small blocks with logs can only support a fraction of that

DIGGLER

iTrader: (1)

2 year bump LMAO.
so i did some cleaning today and to amuse myself i dug out my other motor and hung some parts on it. i apparantly liked the shiny stuff back when i built this thing. not sure how much of it will remain once it goes in the car, but i know the valvecovers will be different. turbos are not clocked in any particular direction.

DIGGLER

iTrader: (1)

comparing the old pic above, it looks like this setup may not clear the shock towers.... i really should have on center turbine housings. hmm...

DIGGLER

iTrader: (1)

25.3

Welp... why not update. lol

DIGGLER

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sailtexas186548

iTrader: (2)

Awesome! I just kicked my build back off about a month ago after a 10 year hiatus, 25.3 SFI book arrived yesterday.

I would love to see some more pictures of youR cage and how it ties into the unibody