Teach me the n/a 4v cobra intake.

[SVT Lurch]

If shortening the runners increases low end torque, then why do truck intake manifolds have such long runners?

The BMW m5 intake runners are long too, and that's a 8000rpm motor.

So that being said, I'm confused on how it all works I guess.

I'm not wanting to do anything I'm just wondering why, and why not.

No clue, I'd ask someone that builds motors. I'm just going off what I've seen/read about on the SN95 cars (which is the intake you posted).

[Diabolic]

Shorter runners move the peak power point upward in the RPM range. How far up there it makes peak power is also determined by the camshaft. IMHO doing a short runner intake on a 96-98 Cobra is a complete waste of time unless you are racing a dyno. 20hp at 6700 rpm with a 35 ftlb of tq loss from there on down. It needs differnt camshaft profiles and some tuning to take advantade of a short runner intake. Both cost a lot of money. Those cars like gears, CAI, tuning, and a small dry shot say 125 or less. With a bullit proof rear and tranny those few mods should get you into the high 11's to low 12's. Plenty for a street car.

[91CoupeMike]

So the short runners and an camshaft to match, with some nitrous would do pretty good with a steep gear?

I personally like to turn higher rpms and drag gears out. So a solid high rpm power band would be ideal to me

[Johnc]

Haha! In his defense they were in the car when he bought it. And in the original owner's (WA 2 FST) defense when the gears were originally put in the car 4.56s (even 4.30s) were not available from FRPP.

Never heard of doing so, but seems pointless, those intakes flow very well.

Are you talking about Jared's car?

[SVT Lurch]

Are you talking about Jared's car?

Yes, but I drove it in when my buddy Adam had it a few years ago.
<---10,000

[Johnc]

Yes, but I drove it in when my buddy Adam had it a few years ago.
<---10,000

He says it has 3.73s in it. That's what michael told him

[greenbullitt]

I know what's missing, I've driven my buddy's 4.10 geared 96. But if I do gears I'll also want to do 31 spline axles and differential. A $300 gear change just turned into a $1200 rear end. I can't justify that much money on a car that is potentially for sale at any time.

1200 sounds really high for a 31 spline

[ihearturanus]

They are 3:73s Trey. Not 4:10s

I want to do 4:56s but havent really had the money to throw at it.


Also, there is no reason to upgrade the axles, not how we drive them at least.

[Steve]

Oh hell yeah. You should drive my cobra to see what yours is missing.

LMAO, Trey is on to better things. His Caddy will eat your Mustang for a snack.

[Johnc]

LMAO, Trey is on to better things. His Caddy will eat your Mustang for a snack.

cts-v?

[shumpertdavid]

1200 sounds really high for a 31 spline

Depends on how you go about it, Trutrac, gears, good axles, install kit, fluid, labor; all ads up pretty quick. I did Richmond 4.30's, auburn limitied slip, mosier 28 splines, install kit, and spherical bushings in my 97 when I had it and dropped about 900 in parts iirc

[Steve]

cts-v?

Yeah. I got Trey a test drive in Will's new 09 CTS-V with the LSA motor. Trey couldn't stop grinning afterwards. Hahah.

[shumpertdavid]

To original post, at some point you reach the limit of the camshafts. The shorter the runner, the more rpm the motor want's/needs to make hp. Even with a blower as big as mine, the power started to nose over @ 7300-7500 rpm. I run an 01 intake, I assume the stock 96-98 cams I have are the blame for the drop off. My intake is basically, I cleaned up the passages going into the lower part of the intake, smoothed the upper section, and blended everywhere I could. I also gasket matched the ports that meet the heads.

[Johnc]

Yeah. I got Trey a test drive in Will's new 09 CTS-V with the LSA motor. Trey couldn't stop grinning afterwards. Hahah.

those things are nice! I was just at the cadillac dealership looking at the cts-v coupe.

[shumpertdavid]

I assume that's the first time you've seen his avatar. I admire those anytime I see one of his posts. I'd like to see some better pics of them for sure