Im currently waiting on a set of AFR Race Ready 220cc heads for my 383 LTX. My old combo was AFR 190cc competition ported heads with an XE 230/236. I wasn't pleased with the low amount of power it put out so i decided to upgrade. Im going a solid roller now and and am trying to figure out a duration to go with. The car is a 96 corvette (3240lbs weight) A4, LT4 11.4:1 383, will be going with a 3400 vig stall, currently 3.07 gears but will be upgrading to 3.73s soon. (not sure what else you would need to know 3" dual exhaust, LT headers, 58mm TB. Im going to go to solid roller now and i made the mistake of purchasing a cam before i really researched it. I feel it may be too large now. Its 250/256 .644/.614 112+2 lsa. Im thinking maybe i should be closer to low 240/ high 240. Any opinions?

 

With a solid roller you can basically go about 8* more in duration to compare to a hydraulic roller. Also, driveability is subjective to what you can tolerate. Your original cam would work well in a 6spd car, but I think its a touch to big for an auto.

 

So essentially i would have comparable drivablity to a 242/248 hyd roller cam? Looking at it like that makes it look not to bad. The two things im most concerned about is idle quality/low rpm surge and the fact that I will be reving under 7k (due to stock a computer) Will this cam leave my powerband just out of grasp? Would i be better off stepping down a ways since i can't rev over 7k? Or will this cam do well to 7k?

 

Maybe i should have asked this in advanced tech?

 

250/256 solid in a 383 is not too big at all. 95Bird is running a solid in that same range in a 355 M6 car. The car drives EXCELLENT on the street not to mention that it runs high 10's at the strip with ported LT1 factory castings. With proper tuning the 383 will love that cam with the AFR 220's. Should make some serious power!
Steve...

 

Is 95Bird Tim Herrint?

Does 95Bird's car have surge problems in low rpms? How is the idle quality?

 

Surging in the lower rpms can be combated with excellent tuning! Now if the cam is to big, then forget about it. I would rather err on the smaller side, trust me you won't enjoy the car if you go too big. Best bet is to speak with others that have similiar set ups and make your decision. Also, do you really want the extra expense of a solid roller valve train plus adjusting the valves periodically?
BTW, I believe in the vettes the pcm will run to 7200 rpms.

 

I already have the almost all of the valvetrain purchased for the solid roller cam. Adjusting the valve lash doesn't bother me as the car is not driven all that much. Actually I am trying to find people with experience with this sort of combonation which is why i posted this thread .

 

Yep that's Tim. The car has no issues with idle quality that he wasn't able to tuned out. Hearing the car idle through the exhaust you'd never know it's a pretty big cam.

 

i thought one could rev way past 7000 rpm. the pcm will just use the same timing and values as 7000 rpm for anywhere past 7000.

 

I would think that if the computer didn't have any references past 7k it would be hard to tell it when to shift the tranny after 7k no? Just my guess but i dunno....