My spec just went to hell after only two weeks
And now I have to take the time to send it to them so they can inspect it, plus the cost of having the tranny dropped twice since I do not have the ability to do it myself. If spec doesnt replace it or at least cut me a sweet deal, I'm going to the twin street.

 

The only problems with Spec that ive heard of are with the tiny springs they use in their sprung disks. I was thinking about the street twin but decied that its just uneeded with only 400 RWHP and more importantly, sense it doesn't slip it will be rough on as hell on the driveline.

Im thinking about the Spec 4 solid disk with the stage 3 compound (You can get any compound you want on them) and using the LT4 DM flywheel. Got a deal on one awhile back .

 

So you're still running the stock bottom end or did you build a stroker instead? I was always curious what you could wring out of your stock bottom end since you broke 12's on stock heads and no giggle juice.

Jason

 

I had planned on keeping the stock bottom end and putting on some AFR heads and converting to the single plane intake and seeing how far i could go.

However, i really ran into some hard choices on the AFR heads and combustion chamber size. If i milled them to come in a smaller chamber so that i had decent compression with the the AFR heads, it really limited my off the shelf piston choices later on down to road for a turbo motor, which is really what i want in the end.

I also ran the stock bottom end without much regaurd for anything. If i put a rod through the block, hit a valve with a piston etc, i really didnt care that much as it was all stock anyways. With the more expensive heads, i didnt want to run the risk of breaking a rod bolt and throwing a hypercrapto piston into the heads and ruining them.

So i struggled with this for awhile. Finally my buddy was tearing down his car and going to ls1. He had a fully race prepped 383 he was parting out, with 7cc dome pistons. Running that combo, i could keep a big chamber on the AFRs, and still keep a decent NA compression (final was about 11.3:1). That allowed me in the future to run a off the shelf piston and drop my compression into the 8:1 range. The rest of the motor will easily handle boost, 4 bolt mains, 4340 crank and h beams etc so it was a perfect match. Not to mention, he made me a very good deal on the motor, and i was able to sell my current long block to a buyer i already had lined up.

Sorry for the long winded explaination. But in short i pulled the stock bottom end and went with the cubes, for the price i couldnt resist. Surprisingly enough, the guy who bought my longblock tore it apart to check/replace bearings, and he said the old ones werent really in bad shape. Guess upper 6000s time and time again didnt hurt it

 

Yeah I hear you on the piston choice. I'm friends with TransAmGT94 on here, and he had a hard time finding forged pistons with .040 overbore and fit 6" rods that would keep a streetable compression. He finally just decided on 5.85" rods for a 400 and got some Wiseco's.

BTW, how many miles were on your stock bottom end when you sold it?

Jason

 

Touch over 81k miles. About 15k of which were cammed miles, and its entire life it was raced.