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-   -   1988 Turbo II VS 1997 COBRA (https://www.rx7club.com/racing-kills-lounge-10/1988-turbo-ii-vs-1997-cobra-513393/)

sliding_fox 02-25-06 09:44 PM

1988 Turbo II VS 1997 COBRA
 
I'm going to be racing a 1997 Cobra with a H pipe, plugs and wires and an Intake, my RX-7 has an HKS F-con, and a full 2.5 Exhaust with a Greddy Muffler (2"-4") and an intake with a Weapon R Dragon Filter, and Manual Boost Controler and will have a HKS wastegate. The car is set to handle 11PSI, with the factory injectors, also how high PSI can I run my turbo at with factory injectors?

His car dynoed at 260 WHP, and 255 Torque.


Will I be able to really compete?

TurboFB 02-25-06 09:58 PM

Probably have a chance at keeping up with it for a while...I can't tell cause of weight...*shrug*

sliding_fox 02-25-06 10:01 PM

also it has 410 gears.... but doesn't stay in it's 2000 RPM of power long at all. half a second at most (I've ridden in the car when it was pushed to the limit)

tjeter 02-26-06 11:25 AM

don't those cobra's run high 13's stock? I'd have to say you would keep up for a lil, but i think he'll get you in the end, i could be wrong though, the only way to really tell is to race him. Wait his car dynoed at only 260whp? That doesn't make alot of sense since they have 305 hp stock, and 300 ft/lb of torque stock it all doesn't add up. Even though his mods aren't serious, i would think they would be putting down more power stock, theres not THAT much drivetrain loss.

RX7_2ner 02-26-06 11:44 AM


Originally Posted by tjeter
don't those cobra's run high 13's stock?


they run 14 flat.

JAPSPECGTUs 02-26-06 12:18 PM

H pipe and plugs in wires isn't much...is it a cat-less H-pipe..wait..or are all H-pipes catless..?

sliding_fox 02-26-06 12:59 PM

remember those cars weigh around 1000lbs more than our RX-7s, also his H pipe is catless

BlkS5TII 02-26-06 01:38 PM

Run him and let us know what happens. I can't tell what will happen since it *might* be close.

JAPSPECGTUs 02-26-06 01:59 PM

You should be able to take em

I ran dead even with a 00 WS6 who had a cat-back from 30-100mph

Mods are in sig.

JAPSPECGTUs 02-26-06 02:01 PM

After that I shutdwon because of traffic. I do have a street port and 4.30 gears, but also...I don't have a FCD. MBC limited boost to 8psi.

Cobalt 02-27-06 12:54 PM


Originally Posted by sliding_fox
also it has 410 gears.... but doesn't stay in it's 2000 RPM of power long at all. half a second at most (I've ridden in the car when it was pushed to the limit)

My 98 Cobra ran low low 13's on DR's with that setup plus a MAF which I don't think gave me crap.. The car LOVES gears. I had 4:10's and went to 4:45's because 4:10's have you shifting right before the traps which has you not in an optimal RPM. That car will pull real hard up top. The best gear to run a race in that car is from 3rd and it just screams all the way up through 5th gear with 4:10's and lower. It's like night and day for the 96-98 Cobras. They came with 3:23's and should have had 3:73 at a minim from the factory. If Ford would have put 3:73's in from the factory it would have been a mid 13's sec car from the factory instead of a high 13 sec car.

Cobalt 02-27-06 01:00 PM


Originally Posted by tjeter
don't those cobra's run high 13's stock? I'd have to say you would keep up for a lil, but i think he'll get you in the end, i could be wrong though, the only way to really tell is to race him. Wait his car dynoed at only 260whp? That doesn't make alot of sense since they have 305 hp stock, and 300 ft/lb of torque stock it all doesn't add up. Even though his mods aren't serious, i would think they would be putting down more power stock, theres not THAT much drivetrain loss.

305x.85=259.25RWHP
300*.85=255RWTQ
That's about right. He should be seeing a tad more with his mods. An offroad pipe he should pickup about 8-10RWHP. The CAI is maybe worth 5RWHP. 4:10's can cause you to Dyno a little lower than you would say if you were using 3:73's. I don't know the formula for this but it's been shown time and time again over on the Mustang forums that the gear change when going above 3:73's on these cars tends to cause them to Dyno lower. Don't ask me why because I say the explanation so long ago but if I recall correctly it made sense at the time.

Cobalt 02-27-06 01:17 PM


Originally Posted by RX7_2ner
they run 14 flat.

I ran 13.8's on factory tires with my Vert and their heavier than the coupes by a few hundred lbs. The fastest recorded stock time for a SN95 Cobra was 13.3's (I think that was a total freak car). Driven well on a good track a coupe can run 13.6's-13.8's.
Here's something to think about and where you guys can nail a geared 96-98 Cobra in TII's
96-98 Cobras came with something called IRMC's. They stand for Intake Manifold Runner Controls. I forget exactly what RPM range but I think it's around 3400 RPM they open up and allow more air to run to the cylinder heads. They were added to these motors to keep good low end TQ and still deliver top end power. Well needless to say these things get gummed up as the mileage adds up on these cars and don't open at the correct RPM, also the little motor that moves them open and closed can also take a dump. When the IMRC's don't work the car looses 25-30 RWHP from mid to the top of the powerband. The engine is trying to breath out of a straw. Mine failed and I didn't notice it at first, then when I had them checked, and then fixed it was like night and day.

JAPSPECGTUs 02-28-06 10:22 AM

Wow ^^^ That's crazy!

jic 02-28-06 02:15 PM

damn!

sliding_fox 03-07-06 06:17 PM

ok... My buddy said something was sticking in the motor, not letting it run optium... it had a weird "peaK" on the dyno sheet. but the rest looked pretty normal.


oh he tried taking the car to the track, he couldn't hook up... even with 285s on the rear! hopefully I can get some wide rear tires for my car so I will not even have to worry abut takeoff traction :naughty:


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