My 97 cobra 1/4 mile/ lil confused w/mph

[GoBabyVroommm]

Ok lets start with mods:

This is all on a 18" Sumitoma's<whatever u spell it> 245/40/18s
Tire pressure 18psi rear, front 30psi

Center Force DFX clutch w/ alum flywheel
CAI
Accufab T body
Adj upper control arms/lower
bbk h pipe with cats
410 gear
pro 5.0 shifter
Knock off mufflers not even a cat back.

Weight: Full weight car with spare in back, nothing taken off and with all the sway bars front/back.

Passes:
1/4 MPH 60FT RPM
1- 14.0 101 2.1 2000
2- 13.8 102 2.1 2300
3- 13.7 101 2.0 2500
6- 13.6 100 1.9 2500

NOTE* runs 4/5 were 13.7's as well.

All these passes i ride the clutch and have to back it off a lil if it starts spinning.

See i'm confused about the MPH. It appears that the car is going faster on 1/4 with higher rpm but the MPH is almost the same?

I plan on staying on 18s but what kind of E/T would i get on a tire leaving at 6k rpm and keeping the car at its 4k power band?

 

[BurningRubber]

13.6 isn't bad considering the mods and being on street tires. As you see, you're 60' comes down, your E.T. comes down given the rest of your run goes as planned.

If you got a set of tires that would hook on near-stock suspension and you didn't snap an axle, you'd likely get into a high 1.7, low 1.8 60' time and drop to a low 13. But, that's driving the PISS out of the car.

Your MPH is a little low. Figure a healthy Cobra would trap 102-105mph. But weather and shift points, and traction have a lot to do with that.

 

[GoBabyVroommm]

Anyone think the 18's might be dropping my mph or face the fact that my cobra is gettin tired? Best honest i got my BIG BOY PANTS on. lol

See that is what i was confused about with MPH. Just seems low compared to my 99 cobra. I was at 109, 110mph with almost the same mode and some weight reduction.

On a side note i'm gettin the rear end freshen up and maybe some new 28spline axels. A lot of my seals have went out and its leaking pretty bad.

 

[BiminiBlueLX]

On a side note i'm gettin the rear end freshen up and maybe some new 28spline axels. A lot of my seals have went out and its leaking pretty bad.

That might help you gain a few mph and a lose a couple tenths maybe e.t. wise by freshening up the rear. You wouldn't want a leaking rear with bad seals. Have you looked into possibly getting an aluminum drive shaft? Lighten up the car and strengthen it some. Or try lowering the tire pressure a little more. Try a drag radial on those 18's too?

Hope that gives you some ideas.

 

[BurningRubber]

Yes, the 18's are slowing you down. A lot? Maybe not a ton, but you would notice a difference in 18's vs. a drag oriented 15" setup for sure, and even stock 5 spoke (non-Bullitt) 17" wheels.

The 97 Cobra is down on power to begin with compared to your 99. The 99 had better flowing heads and cams to match, so it will respond better mod for mod. I'd still think you should be around 105mph.

How many miles on the car?

 

[GoBabyVroommm]

98k miles on it. We have a shop and have a set of bogarts on 15s but i have to grind down my calipers. But most of are cars aren't stock. Lol I gave up on going fast just cruisen now.

But i have a feeling this will not last. More than likely ill get a 04 cobra motor long block and put a D1 on it with a built 6 speed. I've always been a blower guy, all our cars are turbo cars.

 

[Mr. Rustypwnz]

Yes, the 18's are slowing you down. A lot? Maybe not a ton, but you would notice a difference in 18's vs. a drag oriented 15" setup for sure, and even stock 5 spoke (non-Bullitt) 17" wheels.

The 97 Cobra is down on power to begin with compared to your 99. The 99 had better flowing heads and cams to match, so it will respond better mod for mod. I'd still think you should be around 105mph.

How many miles on the car?

wrong.. c heads actually flow less, and the 96-98 cams are better, just better intake on the C head na cars, and the c heads make torque better than the B heads but all out the B heads work better..

 

[GoBabyVroommm]

wrong.. c heads actually flow less, and the 96-98 cams are better, just better intake on the C head na cars, and the c heads make torque better than the B heads but all out the B heads work better..

If i'm not mistaken, the C heads are better than the B heads but when it comes to port and polish work the B heads are better due to the port design.

The only think that 96-98 cobra 4v's have over the other cobras are better n/a cams.

I'm rusty here on my 4v's.

 

[BurningRubber]

wrong.. c heads actually flow less, and the 96-98 cams are better, just better intake on the C head na cars, and the c heads make torque better than the B heads but all out the B heads work better..

Not to say you're wrong disrespectfully, but C heads flow better than B heads stock for stock.

When you port them, you surely can make the B head perform well, but stock for stock C outflows B.

I've heard the 96 cams were the best, that the 97-98's are different, that the 96-98's are best (like you said), that it didn't make a difference... etc. There may be small differences but in reality, how much are we talking about power wise...

 

[GoBabyVroommm]

If your talking about cams different in hp your looking at 12 rwhp. HP isn't everything imo its your combo and power band.

We jacked the thread. Lol

 

[BurningRubber]

It's ok, it's your thread, lol.

 

[Mr. Rustypwnz]

Not to say you're wrong disrespectfully, but C heads flow better than B heads stock for stock.

When you port them, you surely can make the B head perform well, but stock for stock C outflows B.

I've heard the 96 cams were the best, that the 97-98's are different, that the 96-98's are best (like you said), that it didn't make a difference... etc. There may be small differences but in reality, how much are we talking about power wise...

na, all the 96-98 intake cams are the same, SUPPOSEDLY the 96's are better, but i have done some research as far as to get people that had a set laying around to give my part numbers and chit, and all has been the same.. i havent actually mic'd a set to see..

 

[Mr. Rustypwnz]

BTW i have seen YESTERDAY, a 98 cobra tuned, geared, suspension and dr's, going 13.65's at 103mph so dont feel bad, get a set of 4.30's monster tune and longtubes and other key elements, and it will go 12's so easy..

 

[GoBabyVroommm]

BTW i have seen YESTERDAY, a 98 cobra tuned, geared, suspension and dr's, going 13.65's at 103mph so dont feel bad, get a set of 4.30's monster tune and longtubes and other key elements, and it will go 12's so easy..

I'm feeling better about myself. But as for this year I'm done going to the track. I have some things to take care off. But i am planning on a full exhaust with no cats, and a tire.<18's still>

 

[blackfang]

Your ET and MPH can improve. I was running 13.6's@103-104 with an h pipe, shifter and mufflers. Your setup, you should be 13.2-13.3 @105. The 18's are hurting you and practice!

 

[GoBabyVroommm]

Your ET and MPH can improve. I was running 13.6's@103-104 with an h pipe, shifter and mufflers. Your setup, you should be 13.2-13.3 @105. The 18's are hurting you and practice!

SOB i hate hearing that. But just confirms that my engine is gettin a lil tired.

 

[BurningRubber]

Don't feel bad... my car has never trapped over 100mph on motor.