turbo intake

[Nightmare302]

For a turbo street cobra running a modular with gt500 heads, the fr500c intake is as good as you'll get. Unless you spin 8500rpm, you can't get much more top end from other designs but in the process you'll lose tons of low end.

If I ran a Sullivan or sheetmetal unit, I'd have 150wtq until 4000rpm. I'd have a bit more top end but not worth the trade, maybe 50whp up top. The fr500c flows huge volume for its velocity. On paper/mathematically it would take 8000-8500rpm with boost to become a road block.

I'd run that fr500c. You can also get smaller internal port holes/plumes if you need 8000rpm.

I plan to rev mine to 8250. On paper it should peak at 7800 and barely taper down 2% by that point. It'll be mid winter when I go Holley efi stand alone and a magnum 6060 trans so I can safely pull it that high but I can keep you posted how it works out on these (long) plumes.

For a manual trans and a street car an FR-500C is a good choice. For my drag car it's holding back 100-200rwhp on the top end. The shortest possible runner is 10 inches, which would by all calculations puts peak power at 7,250 max. You would gain a massive amount of top end power with those cams and a shorter runner intake. Your dyno shows this, by basically going flat after 6k (I assume you are still using trumpets and this the reason for the lower rpm). I'll be spinning to 8k, and as such would lose a massive amount of power. I should be 1300-1400.

 

[tt335ci03cobra]

With the meth it should be healthy. I thinking you're on the right track. Good luck with the cooling and manifold work, keep us posted how it goes

 

[tt335ci03cobra]

Nightmare, I don't think youll need that much manifold for 1300. I'm on a stock Ecu with a very rich fuel ratio. It's like 10.75/1 and just 28psi. I'm low compression as well at 9.3/1. I'll crack 1300-1350 just going Holley efi, 8250rpm and 30psi (I'm pretty sure anyways. It's at 1208 as it sits).

Another way to look at it is if you get 1300-1400 from an fr500c setup, it'll be very flat from 6200-8200rpm. That's the entire rev range for given gears when shifting at redline. It'd probably be faster than something that peaks at 1300-1400 at 8000rpm but is making let's say 1150-1200whp at 6500-7000rpm and climbing. Average power and what not being the deciding factor. Before you sell that manifold, have you already tried it on the car? What's it made so far? From the results I've had with a mild fr500c, I can't see how a wickedly worked over one couldn't support 1500whp with higher compression, stand alone Ecu/fuel system, and 67's.

Anyways good luck on the project man, it definitely sounds like you have a good plan in mind so it should run great. What is your build using as in displacement, compression, head, cams and turbo size?

Not trying to sound like a know it all, I've just seen good results with the fr500c so far even in as constructed/large plume form. I was actually still gaining at 7200rpm but my n2mb wotbox was signaling a spark cut off at 7200, we didn't realize it until after the pulls. That graph looks wonky accordingly.

 

[Nightmare302]

I'm through a TH-400 so my 1300-1400 would be much higher than yours. I'm 10.5:1, livernois cnc ported heads, custom todd spec'd cams, twin 62/74's. Math says runner should be 5-7 based on induction wave. Your cams depending on position are also helping your engine rev out. I'm also a large stalled auto, so power below 4-5k mean basically nothing to me.

 

[tt335ci03cobra]

That explains it. Auto will command 1750hp+ to put 1400 out. You've got a lot of exducer though with the 74, that will carry the 62 very far. Nice combo, that's going to work excellent.

Are you planning c116 or something else fuel wise? 10.5/1 is what I wanted to go with and e85 but it's 50 miles away up here... I plan to get a flex setup in this winter. I'd like to run it more for the colder operation/safety. I don't really car about any extra power it helps free up. With it being a street car I want to keep it cool and safe.

$1650 for that manifold sounds like a steal. I paid $2300 for mine. I'd been on the hunt for 6 months. I found a listing from multimatic up in canada. When I called he said it'd been up for only 5 minutes. Good people up there, hell of a program they run.

 

[1990jmcturbo]

Sullivan lower edelbrock upper here love it!!