Hey guys, got some questions relating to a Single Turbo Small Block Chevy setup I'm doing. First I'll post some details of the motor and then I have some questions about a CAT turbo I have access to as well as some other potential candidates.

The motor is a small block Chev, haven't decided on displacement yet, either 355 or 383, though more than likely 383. Heads are AFR competition eliminator @ 227CC. Cam hasn't been selected yet but will solid roller. Fuel system is an EFI hardware 8 injector 4 barrel that the rotary wierdos (lol) rave about. I have a lot of the bits including the 9 inch setup and built TH400 with 4000 converter. I'm going to use flipped Sanderson S10 1 & 3/4 V8 conversion headers and a u pipe. I'd really like to crack the 1000HP at the flywheel on race grade E85. Its all going into a 73 HQ Holden Sedan which will weigh about 1200kg with fibreglass panels.

So, on to the Turbos. The CAT I have in front of me has a remanufactured part number of OR-7924. I believe that makes it a 3406E? The exhaust A/R is 1.44 which I know is massive and probably unusable. It's also internally gated so I know the exhaust housings gotta go. The Compressor housing is A/R .81 if I have read it correctly and has the o-ring connector at the outlet. The inducer is 80 or 81mm and the exducer is about 108-110 (don't have calipers sorry). The turbine wheel is about 97 odd mm. My questions about this thing are:

1. Are these basically a GT47 Garrett?
2. Is the COMPRESSOR A/R too big?
3. Can I use an externally gated GT47 EXHAUST housing, will it fit? What A/R should I use?
4. What HP would it support if it were infact of use?
5. Should I just use it as a cool ornament?

The other turbos I am looking at are Borgies, being an S400SX4-75 and SX4-80. Any recommendations here on which one and also exhaust A/R's?

Any way of supporting the weight of the turbo other than than just with the headers?

Thanks so much for any help.

 

Thanks mate you are a champion. What A/R is that replacement housing?
You don't think that turbo is too large for a small block?

 

Sorry for my mass of questions mate, do you mean its a good turbo without the large A/R rear? What do you think of the A/R of the compressor housing? I just did a search on it but can't find where it's been used on a performance application.

 

is that the turbo with the waste gate actuator built in ??
i think i have some bits in the shop??

 

Hey mate,
yeah its internally gated and the housing is 1.44. Need a housing near 1.00 I think from what I have read. The A/R of the compressor is .81, seems most larger framed turbos are .69 or thereabouts. Thoughts?

 

the comp a/r does change things as much as turbine ar
basicly either a high pressure comp housing or high volume housing ( dont worry about that too much.. )

i'll look see what turbin housings i have here off some of the roadtrains / cat motors in earthmoving gear

 

Champion!

 

OK guys forget the CAT, the guy wants too much for it, more than what I can get a brand new Borgwarner specced to exactly want I want. Thinking of an S400-SX4 -76. What do you reckon of this turbo? What is forcedinduction.com like to deal with or himni racing?

 

Guessing you meant forcedinductions.com....... he is a site sponsor here and very good to deal with. there are a few other sponsors that sell the BW units. VS racing, who has posted here is one of them.