Orange 65 Fastback turbo build

cprstreetmachines · 08-21-2007, 12:35 PM

Customers car from Irvine area. It's got a 347 with Edelbrock heads, and a carb. He wants a 9psi spring in it so he's looking at testing the blocks limits. Hopefully he can have some fun with it before the block decides to quit.Hopefully it doesn't do it to me on the dyno.

Expecting 450-475 to the ground with no intercooler.

SS4LUNCH · 08-21-2007, 12:47 PM

Ouch no intercooler. Is he using a factory Ford block?

cprstreetmachines · 08-21-2007, 12:54 PM

yep, its a ford 302 block and the compression is 8.4:1 347. He wanted to run 14psi and we kept telling him 7psi, he went with a 9psi...
The intercooler is the carb They really aren't needed for this power level. His inlet temps aren't going to be very high with only 9 psi. Everyone thinks you HAVE TO HAVE and intercooler, when you really don't. It will make less power for the same psi compared to having one, but we are already at the limits here.Don't need anymore.Partner runs 12psi, no intercooler.

67mustang302 · 08-21-2007, 12:55 PM

I don't think the block is gonna last long. General concensus is a 302 block is good for about 500-550hp at the crank, which comes out to around 450rwhp as a limit(give or take), but it requires a good tune. One of the guys in the 5.0 forum recently has his block fail, a 302(not a stroker) with boost, pushing like 520+rwhp and it lasted nearly 2 years, so it can be done. But a 347 puts a lot of extra stress on the already weak mains of a 302 block. The tune will need to be dead nuts on for it to last. And a blow through carb with no intercooler is only gonna need to be off on the tune 1 time to fail. I don't doubt it'll make the power, but I'd be really careful with no efi and no intercooler. You might try to convince him to go for 6-7psi for some safety, so he doesn't try to get you to build him a new engine when he blows his up

SS4LUNCH · 08-21-2007, 12:58 PM

We'll some people have money blow(up) and have to learn the hard way. The block should handle it though. Of course detonation is another thing

and I know Santee isn't cool in the summer.

cprstreetmachines · 08-21-2007, 01:04 PM

I tried to get him a little lower on the boost. But for some reason turbo are extremely forgiving on blocks. I don't get it, but you see guys running 10's all day long, and some into the 9's for quite a long time before it gives.My partner believes some much you don't need an intercooler he took his off to make the point. People tell him that all the time at the track, but it hasn't blown up yet and it made 460+ at the tires with a carb.He'll put an ijection kit on it when he goes to 20 psi though.

SS4LUNCH · 08-21-2007, 01:14 PM

Have you ever run a water/meth injection through a carb setup? I don't think it would work right being blow threw design but it's an idea I've been beating around for my Kenne Bell.

67mustang302 · 08-21-2007, 01:18 PM

Intercooling isn't necessary like you said, especially as you pointed out with a carb, since the liquid fuel that's vaporizing is an endothermic reaction, and absorbs heat as it occurs. But, a tune is more stable with an intercooler than without. The lower that induction temp is, the more forgiving the combustion process is.

And as far as turbos being forgiving, yeah, since you can have less combustion pressure for the same power level compared to a supercharger, since you don't have to rob engine power to run the compressor

cprstreetmachines · 08-21-2007, 01:27 PM

Quote:

ORIGINAL: SS4LUNCH

Have you ever run a water/meth injection through a carb setup? I don't think it would work right being blow threw design but it's an idea I've been beating around for my Kenne Bell.

It gets done quite a bit. Some shoot it under the carb, but most like to put it as far away from the inlet as possible wo give it more time to cool. Which I guess is why they don't work as well with blower like you have. But I'm know expert on that by any means.

This one my be getting a write up on it. Who knows. We where told it was possible, but haven't heard back yet. But the customer can't wait for ever.[8D]

SS4LUNCH · 08-21-2007, 01:29 PM

Intercooling isn't necessary as long as boost levels are moderate or you run race gas. My preference is to use an intercooler. It robs a little boost but makes up for it with cooler IATs. I have no experience with carb setup though. The tune is the key.