wot kenne bell in 5th question

[yellowsc281]

Maybe someone can give me more insight of what may be a myth. I've noticed on two different sites people saying not to floor it in 5th gear cause you'll blow stuff up. Where are they getting this information from and why would that be true. Doesnt make sense to me. Any body ever hear of this or had any problems relating to this?

Kinda concerned cause im getting a kenne bell 1.7 installed at a shop as we speak. Car is a 99 with a stock block.

 

[bluestang41505]

I've heard about it for a cobra not the 2v. Some do it all the time and some pop something there first time, just depends on the mods. I'd say since your sc'ing i would deff not with all stock block.

 

[lowflyn]

The main issue is with the 03/04 Cobra motors as the clearance between piston and cylinder wall is so small. The amount of heat build during a WOT pull in 5th or 6th (both O/D gears) is enough to cause this small clearance to make it to 0 in several cases, causing catastrophic meeting of piston to cylinder wall.

 

[CPRsm]

I don't think it's a myth, especially for any boosted car. Detonation is a combination of heat AND time. You can juggle the two, and that's where you get a good tune. You can not walk the fine line with a tune for a car to run 1/8 mi, and turn around and take it to the standing mile. Exaggerated, but hopefully makes sense. If you push the car to the verge of detonation at 660 ft, if you go much longer you will have problems. Same goes for gearing. You load that engine MUUUUUCH harder in 5 or 6th than 4th gear. So time spent loading the motor goes up, causes more heat, and if the tune isn't meant for it. bye bye engine.
If you took two cars with exact same mods, one built for 1/8mi racing and one for the Texas mile, same boost, etc, you would see drastically different tunes for each, probably even different timing maps for more sophisticated cars. That's also why wen boost (heat) goes up, timing comes down. Hope that rambling made a little sense.

 

[snakerider]

the main issue is with the 03/04 cobra motors as the clearance between piston and cylinder wall is so small. The amount of heat build during a wot pull in 5th or 6th (both o/d gears) is enough to cause this small clearance to make it to 0 in several cases, causing catastrophic meeting of piston to cylinder wall.

+1

 

[yellowsc281]

thanks guys for all the input. Ill be getting my car back this week and im pretty excited to see what it will do. Going from a rattling eaton to a kenne bell 1.7 should be a nice gain.

 

[THAITED]

Don't floor it in 5th unless you really have a good tune. Plenty of fuel and less timing for safety.