[mpe331lx]

I recently did a mark8 4v swap into a friends 2001 GT. The engine is a stock 98 mark motor with a set of 96-98 Cobra intake cams and a 96 Cobra intake.

Hers the rundown of the mod list:
Intake runners shortened 1.5"
IMRC delets (Composite)
BBK 1 5/8 longtubes and O/R X
SLP LM cat back (annoyingly loud as shit!)
UDP
JLT CAI
03 Cobra 90MM maf
24lb injectors
Aeromotive rails W/ FRPS adapter
Zoom clutch (slipping)
Street tuned by Josh Levin
4.56 gears
Inexpensive drag oriented suspension (4cly ft springs, lakewood 90/10 50/50, cheap rear control arms)
Summit stars/ 26/10.0/15 ET drags

He had only had the car to the track two other occasions with the 2v and had not had too much set time at the track, But he was able to make many 12.5 passes and the best was a 12.47 @ 109! That was with 4.10 gears.

Here's a vid of that pass:

YouTube- Broadcast Yourself.

YouTube- Broadcast Yourself.

For the next event I swapped the 4.10s out to a set of 4.56's (the 4.10s are going into an 8.8 that I'm building for my Wife's LT1 Camaro).

He was able to pull of a few 12.3's with a 12.30 @ 111.9 with a 1.67 60ft being the best run of the day. He was alo able to get a 1.62 60ft time, but the slipping clutch hurt the ET on that run. Still a little ways off from the goal of running 11's N/A, but it's getting there.

Sorry for the sh*tty cell phone pic.

Once he can hit an 11 N/A (and gets a clutch in it), either the 4.56 will be swapped out to a milder gear, or a swap taller slicks, and the N20 kit will be re installed to shoot for a 10 with a close to stock mark viii motor!

BTW, I also pulled off an NPB in my wife's LT1 Camaro with a soft 1.9 60 ft:


Gotta love December 's track conditions in FL

[330CubeGt]

Damn thats a stout car. Nice work!

[gray8188]

Nice i wanna do the same swap.. I was the one that had him ask you about it lol.. I just need to get the money now..lol

[mpe331lx]

Originally Posted by 330CubeGt Damn thats a stout car. Nice work!

Thanks man! If he could ever scrape enough money together to do the clutch (and at the same time, swap out the BBK headers for ones that allow trans removal for future clutch/trans jobs), maybe he'd be able to hit an 11 with it.

Originally Posted by gray8188 Nice i wanna do the same swap.. I was the one that had him ask you about it lol.. I just need to get the money now..lol

Good shit! You wont be dissapointed!

[330CubeGt]

Ive been thinking of putting a mark motor/trans in my 96 V6 leave it stock with maybe a 3.55 rear gear since its my beater.That setup would probably have about the same gas mileage and 150 more hp lol.

[bitemark46]

Phil,

What did cut the runners with and did you put the belled ends back on?

I hate taking the stock runners out....I always seem to burn myself since I get the whole intake so hot with the MAPP gas. lol.

[mpe331lx]

Originally Posted by bitemark46 Phil, What did cut the runners with and did you put the belled ends back on? I hate taking the stock runners out....I always seem to burn myself since I get the whole intake so hot with the MAPP gas. lol.

I used an oxy/acetalene torch with it regulated down to burn off the epoxy and remove the runners.


I used a hacksaw to cut 1.5" off. I didn't weld on the bells, or epoxy the transitions. It was done in a short amount of time (and for next to nothing$$), so I wasnt about to spend too much time on it.

I followed a write up to where it was tested on a flow bench that the runners flowed more CFM with the ends welded back on, but they still flowed way more then the engine could take advantage of, and the lack of the bells would not have a negative impact on performance.

Has it been proven that thay do?

Also, when welding them back on, do you TIG them?


I still have the ends from his. Also I wnet on the consevative side and only cut 1.5. I've heard if you go too far it can hurt performance. Has anyone shown a difference between cutting 1.5 and 1.75 off?

[bitemark46]

There is no solid proof on if the belled ends make a difference. I just put them back on based on the concept of the less sharp turns for the incoming air the better. As far as tigging them I think so. I can't weld so I dropped them off at a shop to have the welded back on.

Anything over 2" and you start to lose low end. My early intakes I cut 1.5". Now I cut 1..75" off. I haven't seen a drop in low/mid range power. I've always want to completely remove the runners and bosses and put a straight tube in there that points directy to the back of the valve with a small belled end. A few have done it but of course they were very secretive.