It's been awhile since the last update and we've made some changes, including some that we wish we didn't have to. The TH200-4R blew out the front seal and Geoff was left sitting on the side of the interstate. The FHP let him know that the car had to be moved, NOW. So we hooked up a tow rope, of course without dropping the drive shaft, and the tranny froze up on the trip home. That was an expensive mistake. We now have a TH350 with a B&M Holeshot 3000 torque converter installed. Before installing the tranny, we put in a B&M ManualPak so that we could do away with the vacuum modulator and, more importantly, the throttle or 'kickdown' cable. I still feel that the throttle cable adjustment had something to do with the front seal failing in the first place. So now we have a full manual trans without the worry that the transmission line pressure is incorrect. The Holeshot was a big help with the fairly lumpy cam we have in the motor, but the car is so light we can't take advantage of the full 3000 rpm stall. But we are happy with it.
Changing transmissions also forced us to change tranny mounts. Grant, at Granny's Speed Shop was very cordial and swapped the TH200-4R mount for a TH350 crossmember at no cost. But we had some downtime between finding another transmission and an understandable shipping delay by the USPS, due to the terrorist attacks. The swap to the TH350 was very easy and accomplished in an afternoon. I am glad we saved the leftover parts from the B&M Meagashifter because we had to convert it back to a 3 speed shifter.
Next up, we added a 5" snorkel scoop to a spare hood we had, mainly because it looks cool. It never ceases to amaze me how popular our little RX-7 with the 350 is at the track. There is always a crowd around the car in the staging lanes, with many questions about how we did it. We love it! Especially when they find out how easy it really is.
We also sprung for Granny's headers, after trying the 4th different set of off-the-shelf headers without luck. The RX-7 steering box is just in a bad place. The geometry of the headers directed the exhaust toward the transmission, so we installed 2 1/2" ID 'downturns' on each collector, angled away from the tranny and down. They were $2.99 each at the local auto parts store and fit perfectly. (Note added 8/13/2003 - I have been told that headers for an early sixties Chevy II will fit)
Finally, we purchased a set of 24.5 / 7.0 X 13 M/T ET Drag slicks from a local import racer. They may be the smallest slicks you can buy, but they made a world of difference at the starting line. Now when we make changes to the car we can actually see the results, whereas with the street tires, the inconsistent tirespin had our ET's and RT's all over the place. With the exception of one pass, Geoff's other three reaction times were .539, .521 and .506!
Soooo, with those changes, last night we were rewarded with a 12.86 @ 106 mph run. And that is with our little 8.5 to 1 compression motor with a 600 cfm vacuum Holley street carb. This is really getting to be fun! Today we are going to install a Weiand single plane intake manifold, seal the carb to the hood scoop, remove the choke plate from the carb and install some light advance springs in the distributor. Which brings me to another unwanted purchase. Because the car was down for nearly a month with the blown transmission, I wanted to prelube the motor before we started it again. Upon removing the junkyard distributor we discovered it was nearly frozen up. It took a lot of torque to spin the rotor. So it was back to the Jeg's catalog and a new Accel street replacement distributor for just over $100. The used parts are biting us.
Well, that's it for now. We'll be back out to the track on Wednesday to see how she runs
again. Until next time, smoke those Mustangs and Camaros and as always, HAVE FUN.
P.S. I'll get some more pictures up as soon as I can.