Today I pulled the exhaust system off and added 18" of collector extension. On the first pass I ran better than my previous best. A 7.331 the previous best of 7.369. Not a huge improvement but I had be running 7.41-7.45 (with an occasional 7.39 or so) consistantly for over a year. Second was a 7.37. I jetted up and the car slowed down even though the temp dropped. 3rd was a 7.41 and the fourth was 7.38. Not big changes but enough to tell me the carb is now too rich. I'll drop it back the the old setting and perhaps try going leaner yet. It possible the carb was on the rich side with the exhaust system in place. With the leaner jetting the 60's were both 1.61 with the richer jetting the 60's were 1.64 and 1.65.

Boy, is the car LOUD uncapped. I was surprised they let me run since they require mufflers.

I got to meet Enrique (Slowpoke70). A very nice fellow. Hopefully, he'll get his car back together soon.

Nice Pat. I used to run my car uncorked all the time, but never with extensions. I might have to try that. Did you have turndown on them or anything, or just stright 18" pipes?

Cool, I almost went to Irwindale tonight except that I had a late afternoon back adjustment so I thought it would be a bad idea.

Pat, you have one of the hardest working n/a 355's that I know of - yet you keep finding more and more performance. I'm gonna have to start some serious tuning on my 496 if I want to stay in front of you :eek: I don't know how far you will keep developing your '67 Elky, but I have a customer with a nasty n/a 331 '68 Camaro running 10.6x's! How about going with a big solid roller, very high stall converter, and a trans brake, it would pull some nice wheelies and fly for sure.

Thomas

:D It sounded sweet! Awesome runs. And even though the 67 is a beast, I still like the look of the 66 too.

Nice meeting you too Pat! graemlins/thumbsup.gif graemlins/thumbsup.gif

Nice going Pat!! Good to hear the elky is treating you right, wish I could have been there racin in the other lane.
Take care!

Congrats on the new best Pat graemlins/hurray.gif graemlins/beers.gif

Greg, just straight extensions. Quite a while back I ran uncorked without extensions. I saw no change in ET, 60', or MPH. With the mufflers on, I always had a hard time getting smoke in the burn out. Last night I smoked 'um like never before. I guess the 2.5" system is too small for the engine.

Thomas, it would have been great to see you there. My next major upgrade will be a converter, as you suggested. Probably a 4500 or maybe even a 5000. The current one flashes to 3700. I'm going to check with Munsinger for one. Last time I check there was a 3 month wait. If that is still the case, I could have one for the start of next season. Continental would be a good second choice if Munsinger takes too long.

Thanks, all,

Only 3700 rpms? I think you will see big gains with a looser converter. When I went from the 10" ATI to the 8" ATI, my stall went up about 1000 rpms and my ET dropped about 3 tenths.

3 tenths is a big gain. Now I'm even more interested in changing. Now I want to do it before I go to Bakersfield.