I have a single turbo cobra, running 19 psi on 94 plus water/meth, with an 03 mach 1 intake. The car is essentially a dd street car, makes good power I'm just curious if switching to a sullivan lower with an hpp upper would be worth anything or a waste of time. I might be going with a larger intercooler and larger cold side this winter so I was just curious if this would be worth doing? Car has a built motor, right now I spin it to 7k it does pretty well.
turbo intake
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What cams? If you are running stock cams there would be no need. The sullivan only shines in high RPM and a stock cam would fall off by the time the sullivan wants to make power.
He'd be the one to ask. I'd personally stick with the cobra intake, not knowing about the cams.
I have a Sullivan on stock cams. Make's some steam up top where I want it to. My car is built to dominate the streets from a roll and it does the job. Your car is a DD street car on low boost, I'd leave it be.
The sullivan runners are very short, they want very high rpm. If you prefer streetlight to streetlight spool then talk to Matt Hayes and have your cobra intake shortened some. He will find the sweet spot between the two. You could pick up another 30-50rwhp depending. He's very reasonable in price but it does take a bit of time to make a short runner. If you are on Todd's facebook group he's easy to find. He's the one working on my sullivan/gt head 5.4/4.6 freak show intake.
Ya the car right now is a bit lazy already, and then from 4k up it pulls hard. I really only do hwy pulls with it. I'm still 6 speed so just was curious, I mean it already makes good power but, you end up always searching for more.
Ask Todd, he'll give you great advice. It would depend on the cam specs and head work. There's a lot of good results from running aggressive heads, cams and a mid range manifold that can hold flow well into high rpm. If the manifold can maintain a high enough volume of cfm without creating turbulence, it doesn't need to actually flow all that much cfm. Rpm will use the steady peak cfm to good use for atleast another 1000 revs before it starts to fall off.
An inexpensive and very easy option is to try a ported Mach manifold. It would be plug/play. You can find them reasonably inexpensive and if it does or doesn't work, you can sell the non ported unit or the ported one. I'd go that route first and see how it affects the powerband back to back same day, dyno etc.
I went fr500c but that requires fgt heads and so many changes. Try to get more outta the current setup and go that route, a solid ported Mach unit is probably gonna work great
An inexpensive and very easy option is to try a ported Mach manifold. It would be plug/play. You can find them reasonably inexpensive and if it does or doesn't work, you can sell the non ported unit or the ported one. I'd go that route first and see how it affects the powerband back to back same day, dyno etc.
I went fr500c but that requires fgt heads and so many changes. Try to get more outta the current setup and go that route, a solid ported Mach unit is probably gonna work great
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I'm selling my FR-500C to get to a modified 5.4 sullivan to fit my GT heads on my 4.6. Mine was actually modified by removing the trumpets and bellmouthing the edges to shorten the runners but for a big stalled auto drag car I just need more peak. If anyone ends up wanting one I'm selling mine pretty darn cheap.
PS what makes the FR-500c's good at a broad range is their very large cross section. The longer runners help low end and because of the large cross section they don't fall off as hard as other intakes and tend to just flatten out towards the upper RPM's. They are outstanding street intakes.
How much?
With the ultra rare coolant cross over, all parts, stock tb, IAC and as it sits modified by Roush Yates I'd take 1650 shipped. They go for 2k+on ebay stock without the cross over. I've not spent much time trying to sell it because it's a cool as hell part that I didn't want to sell just because of it's "neatness".
I'd keep it if I were you. I have one BNIB.
I have no use for it right now. It just sits in my shop looking neat.
Mine works great. Making basically peak power from 6k to 7500 on 11psi and from 6300-7500 on 28psi.
It is very hard to over work an fr500c, but it is always happy and eager to flow low and mid range power.
I have a very high rpm combo:
-9.3/1 compression is low
-t4 62/65 turbos are very big
-gt500 heads stage 3 ported are caverns
-MMR stage 3 cams are very aggressive high rpm units.
-3.73 gears don't create much load.
-my artistic cold side has 3 feet of plumbing from the intercooler to the throttle body.
That said the fr500c balanced everything beautifully.
^28psi and very rich for safety.
^11psi pump gas.
It is very hard to over work an fr500c, but it is always happy and eager to flow low and mid range power.
I have a very high rpm combo:
-9.3/1 compression is low
-t4 62/65 turbos are very big
-gt500 heads stage 3 ported are caverns
-MMR stage 3 cams are very aggressive high rpm units.
-3.73 gears don't create much load.
-my artistic cold side has 3 feet of plumbing from the intercooler to the throttle body.
That said the fr500c balanced everything beautifully.
^28psi and very rich for safety.
^11psi pump gas.
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.
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.
Ya I wish I had some gt500/ford gt heads. My step made 790/735 at 19psi, and pump 94+water/meth rich and not leaning on it, which I think is pretty decent for a street car that gets driven a lot. My iat's get a little up there on warm days the hellion intercooler I thinks a little small , It's just about time to put the car away here for winter months, so I'm just figuring what to do during the winter.
For sure, ya the heads make all the difference. For nightmare I think it would work good but on yours I'd try and find a ported Mach and see what it does same day/dyno back to back with the current one you have.
800 with a streetable single with a Mach intake is phenomenal on 19psi, congrats man, id be very happy with those numbers on that setup. Stone reliable too.
Check into rewinding and refreshing a used 1996-1998 Lincoln Mark 8 fan when you go bigger intercooler, only way to go and it's ~$150 total with used fan and rebuild.
800 with a streetable single with a Mach intake is phenomenal on 19psi, congrats man, id be very happy with those numbers on that setup. Stone reliable too.
Check into rewinding and refreshing a used 1996-1998 Lincoln Mark 8 fan when you go bigger intercooler, only way to go and it's ~$150 total with used fan and rebuild.
ya I'm starting to look into better cooling for the car. It doesn't like the ac being on, when its super hot out sitting in traffic the temps start to climb. Other than that the temperatures do what they should. I think a larger cold side and intercooler will keep the iat's lower during 2-4 pulls. I have the meth spraying directly into the upper intake so I'm not sure how much heat it's taking out.
Ya the car has been good, tob is making noise about the only thing making me mad at the moment.
Ya the car has been good, tob is making noise about the only thing making me mad at the moment.
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