I agree with Walt. Actually with that lousy 60' it is suprising it ran that low of an ET even with the great MPH. Sounds like it really comes alive once it gets moving. Have you rewired your switch-pitch trans for manual activation? Use it off the line and then shut it down. Does your switch-pitch converter even work? Easy to tell with a manual switch. As was suggested drop a 3 speed T350 and 3000 stall in there and even without the rear gear change you'll pick up a chunk of time. Walt, I don't know how you revved your 401 to 6000 rpm. My '65 stocker felt fine to 5500 but that was it. When I first ran mine with a 12 bolt I put in with 3.08 gears and the ST300 along with 28.5" old school ribbed M&H's the car came off the line without a peep and made its way down the track. After about half track my buddies who were watching kept yelling out "Shift, SHIFT!". I was watching the tach and I finally shifted at 5500 around 100' from the finish line. It was running something in the range of high 14's@90. Later on when I hard wired the switch-pitch I found out it didn't work. I fixed it by replacing the converter with one from the junkyard. I think it was $10 at the time because it was in a bucket laying beside a car. That is why I asked about the switch-pitch earlier. The car really came alive later when I installed a set of 4.56's with the 2 speed. Put some 4.56's behind that 300 and run some mid 13's.
:grin: It felt happy there.:grin: It was the '83 GS Nats. I had just swapped in the 425 from my old gold '66 GS (wrecked:ball into the blue one I bought to replace it. Didn't swap in the St400 and 4.11 rear yet, it still had the ST300 and 2.93 rear. I ran against Lee Laursen a couple of times in his 'red '65 GS 4 speed. He won some, and I won some. It was a fun match up. :TU:Anyway, it was my first run in the car and I was watching the tach and seeing redline and the traps coming up so I figured it wasn't worth shifting at that point. Finally shifted at the finish line. The time slip was a 14.67 @ 95.1 mph. Doing the math with 28" tires (L60-15), 2.93 rear, and 1.76 ratio in the ST300 gives 5890 rpm. That's a heck of a first gear!:grin::grin: The next couple of runs it slowed a bit, maybe because it was (slowly) shifting entering the traps. Joe, My 300 Special had a Petronix in it since around 1998. I tried a GM hei first, but it wouldn't run right for some reason. Carb is a stock 66 340 AFB. Never ran it at the track.
great story Walt. that was like running 515-516 gears if it was in drive. ---------- Post added at 10:55 PM ---------- Previous post was at 10:35 PM ---------- its working the tranny was rebuilt a long with the converter with a little extra stall. before the engine rebuild the 60ft time was 2.60. never was going to keep the 2.78s just wanted to see how it ran for the heck of it with them.
with 3.23s in the car ran 14.27@101 with a 2.27 60ft time. the carb acts a little funny out of the hole have to play with try to get it right.. did do a 2.17 60ft time with some tire spin but didnt finish the run. car was built as a driver idles at 600-650 rpms. 2-speed, points and no intake or headers. am very happy with it. high rise intake and headers if they made them would have to be worth 4-tenths.
Damn, that thing screams. You built a good one! For comparison, my blue '66 GS has run a 13.41 @ 102 mph, 1.97 60 ft with some wheel spin. 4.11 rear with ST400. 3900 lbs race weight. I have better gearing and more torque, but you have comparable (if not more) hp! You still have a high e.t. for the mph... My GS responded very well to a faster timing curve. Give that a try. Do you think advancing the cam would help? Nice work, but I want to see a 13 second time slip from you. You're almost there.:TU:
gee wiz Walt i was happy at low 14 teens now you get me going to 13 teens so i wont be happy till then, just kidding LOL. ran a 14.23 with a 2.20 60ft time i think the engine is loosing up a little. just need .25 tenths. i did play with the timing curve the best i could mostly in by 2500 rpms, i will bring to my machine shop and let him do it on the machine. hows your set up, what specs should i tell him, all in by when ?
I have no experience modifying those 300s. So, I don't know how the manifolds flow. In general shorties give up some low end and midrange torque to full length headers.
The Stock Manifolds flow great. Give them a look. They have seprate runners that are easy to port out. Look inside and you can see the bolt bosses. I grind them down towards the flow direction. They can be port matched to the ported exhaust on the head. The outlet has a lot of metal you can get off too. PONCH
Best idea there is right there. $100 for a used TH-350, 3 hours to swap it in for the ST-300, and you have a totally different animal on your hands...
I know you said the switch-pitch works but are you using it manually going down the track? On at the line and turn it off after the 60' marker would be about the best. If you are still using the setup on the throttle arm it comes off before you can really floor it and then comes back on once you floor it so it slips some down the track. Could be worth something. I doubt having the curve fine tuned will be worth anything compared to the fast curve you have now. Something to try is a 1" 4-hole spacer under the carb to perk up the bottom end. Does it feel like you are right on the edge of tirespin? If so it could get more tricky. May be time for a better set of tires. Walt, I found a picture of Lee's red car from back in '83 but I couldn't find one of yours. I do have some somewhere from other events and I know I have one of the gold car at the Street Machine Nationals before that. I actually stopped at Lee and Pam's house in Roanoke VA in 2010 on a long way around trip to the GS Nats. He brought out some old pics and there was a maximum amount BSing in a short time. Doesn't have any Buicks any more but he still has some parts.
On my 64 I went from a TH300 to a TH400 with a 3000 converter, but I also changed gears from the 2.78 to 3.90. Those two changes were worth exactly 1 second off the ET.
i have a on off switch on the nailhead not on this one.do you think it will kick off that quick and go back to low stall? i have a 4 hole 1/2 inch spacer now i will see if theres space for a 1 inch. ---------- Post added at 06:42 PM ---------- Previous post was at 06:39 PM ---------- wow that is 10 car lengths in a 1/4
It was a ton more fun to drive both at the track and on the street. The 60' times alone went from 2.20s to 1.80s.
Hey Joe , have you gotten your 60 down? Hope you can get it together and hit 13.9. I think you got pretty close with your plan of a 14.0 street cruiser with a 2 speed tranny:TU:
took the 750 edelbrock and put a 650 edelbrock thunder on. little better driveablity little more low end response but..... lost 2.5 mph. everybody says the 350 likes big carbs, i guess so does the 340. 650 is now for sale lol.
