Where to start....
So the fuel change was a good thing for the car, off E98 and onto RAT K16. ATM we are at 72-74% duty cycle @42psi and log wise the car is happy. It has not lifted the head, even though its spendy I now have some street miles on the car and built up the confidence I need to get back to the track and try and try to better our 2011 peak of
[email protected].... that seems like a lifetime ago now but we are still after it.
At the end of the 2014 season we hot lapped the car and hurt the trans, and also burnt a hole in the #4 exhaust runner into the coolant passage on the center divider, and we had major clutch slip issues with the Quarter master twin disk, and we broke an ass load of rear axles along the way.
So pulled the head and valve, welded and reinstalled, ordered a Competition Clutch Triple disk and DSS stage 5 rear axels. I forgot about the trans over the year and fixed the head issue, then at PG in 2015 with the Rocket boys holding up the show we figured out the trans was hurt, and we were limited to WG boost pressure, wiring issue to BCS. But the final pass of the day was a 11.8@130 with only 21psi.
Now onto this year... after helping 2 local guys with trans builds I was trying to figure out how I could make this syncro mitsu parts trans work. I am still in the boat of no dog box, even the face plated trans at list price is out of my sights. I also worry I am well beyond what the stock gears can handle and putting a ton of money into faceplating does not make sense.
Also we were are having a hard time to get the car off the line at a sticky track, so the tall EVO 3 1st gear and 26" tall slicks proved to much. We were not able to up the power at the line enough to get the tires to spin in fear of breaking stock driveline parts, we adjusted the rear suspension to limit weight transfer, but with the hurt trans, low boost, and limited track time its hard to say if that will help us.
So over the winter I ended up using a Stock DSM 1st gear, but with reving to 9800rpm the 1/2 split is not ideal but working atm, and with a hole stack of fresh synchros I also shimmed the trans super tight, I found some info on how much more pre load I should be putting in based on HP level.
We also finalized our plans to make this a 4 speed trans to reduce weight of the input shaft and make less work for the synchros. So all said and done we were able to reduce the weight of what needs to change speed on shifts by 17%. Its a little harder to get into reverse but the up shifts have been super smooth, I also installed a trans temp gauge so we can make sure we have enough trans temp and not to much to over work the fluid. This was a easy modification and I was able to eliminate everything to do with 5th gear. So the trans is a little easier to work on now, lol.
I also picked up a dash cam and made a mount for the harness bar and we now have a little bit of good footage from inside the car and I am excited to get some footage at the track with it also.
HP wise IDK where we are at, but at 42PSI the car goes from 60mph-130mph in 4.15 seconds with a passanger. The numbers are looking good and over the next few weeks I will get updated pics and some hard data from the track.
I also raced my buddy Bill in his 69 chevelle with a 800hp BBC and a TH400 trans. He did a 130' long burn out, but pulled to my front bumper, then I shifted into 2nd and drove around him, with a 275lb passanger, this was at 38psi peak bleeding off to 32psi. still working on the ECB stuff, which is better now and around 42psi.
~John