Mike - are those Mikey Thompson ET Drag Radials or ET Street Radials ....there IS a difference - totally different tire. While the drag radial looks more like a slick, I know quite a few Buick guys (myself included) who could not hook (myself with BFG Drag Radials). I went from never being able to hook to lifting the front left tire off the ground !! ET Drag Radial ET Street Radial
Greg, I'd love to be a REAL lead foot if I could figure out how not to do John Force imitations every time I launch. :Brow: Alan, My mistake, I have the ET street drag radials, I figured you were talking about them, since everyone told me they were the end all be all in traction. ou:
Alan you are using the top pictured tire? The ET Drag Radial? What size? On a Buick 15" ralley wheel? Standard offset?
No, the bottom ones - 275-15's in a 26" tall diameter .... I think thats the 50 series The rims are Stockton 15" buick mags widened an inch (8") and the offset @ 5 1/8th. o No: She hooks like I've always asked for ... finally. I do have Metco upper and lower control arms hiding back there.
I've had both C_R and W-R with a Poston 112 cam and the C-R with 3.36's was horrible around town. The thing would start lurching and you'd have to push the clutch in to make it stop, or give it some the throttle. Something you can't always do in traffic. With a good 455 I think either first gear would allow you fry most tires at-will with a little bit of clutching, but driveability with the C-R will suffer unless you run at least 3.64's, but preferably 3.73's or 4.11's. As mentioned, that rear gear ratio with a 4-speed sucks anywhere but in town or at the track.
The lurching you experience could be too much ignition advance for the rpm. If your distributor is stock make sure the stock rubber advance limiter has not fallen off. If your distributor has a re-curve kit installed make sure the brass advance limiter is in place. Too much advance was the culprit on my car. I disconnected the vacuum advance and the lurching disappeared. I backed off the timing a few degrees with the vacuum advance hooked up and the lurching disappeared. I have had this problem on my car with different camshafts and compression ratios and with the M-20, M-21 & M-22. The transmision ratios had little effect especially in 4th gear since 4th gear is the same. Shifting down 1 gear removed the lurching on my car. I have run 2.56, 3.31, 3.42, 3.73 and 4.11 rear gears. Adding more rear gear will help reduce the tendency to lurch but reduces highway cruising comfort due to the increased rpm, but sure is a blast to drive. Finding the happy medium is tough. There are always trade offs.
David thanks for that suggestion, I am running more advance now than I did with my old engine. Its the same distributor and curve as before but this motor seems to love it the more i kept dialing it in. Plus I am running Vacumn advance. As soon as it warm back up i will take out some advance and see the effect.
Possible, although the same combo went in another car with a M-20 and 3.73's with no more problems. It's all been parted-out for years, and I am now firmly in the "automatics are best" category. Haven't missed a shift in years, except that time the sprag exploded....:Smarty:
I love reading this thread! I though I was the only nut swapping around rears, and trannys, to get that perfect "WOW" factor! (and trying to explain to my wife why I put different gears in every winter!) I had a close ratio muncie, and loved the way it performed, but was disappointed in the launch, with 2.93's, so swapped in 3.23's, then went to a sag with 3.50:1 first gear. Now, I rebuilt the muncie, installed a new posi, and 4.11's! Just waiting till the snow, and salt are gone!
Yea, I've read that. I'll be at a little over 9 to 1. I think that'll work, without limiting my top speed to 80 mph!!!:laugh:
That combo will be a ball to drive. I know I enjoyed mine while it was set up with the 4.11. No need to downshift to pass cars. But when you do downshift to third you can hit 4th gear and get rubber beside their car.
This thread has been real interesting,my 4spd car inherited an OLDS 12 bolt rear with a 323anti spin rear---problem is a 220 first gear and 323 really needs finesse to get rolling,because the OLDS carrier has ONLY 2 gear options 342 and 390 could I get the 390s and mount 295x65x15 MT street radials on 15x8 Buick rims and get me a decent takeoff? These tall tires will also allow me to cruise @70/3046 RPM which is livable(60 mph=2613). Pete
:idea2: hey Pete..... here's an olds parts source that has parts and a lot of info on the olds 12 bolt..... http://www.supercarsunlimited.com/ http://www.supercarsunlimited.com/info/tech/diff_id/diff_id.htm http://www.supercarsunlimited.com/Items.cfm?CategoryID=278
With a 2.20 first gear and a 3.42 rear gear I think you will still be disapointed plus add that really tall tire and it will make things even worse. currently your 3.23 rear with the 2.20 first gear 2.20 x 3.23= 7.106 overall ratio A 3.90 rear with the 2.20 first gear 2.20 x 3.90 = 8.58 overall ratio. A 3.42 rear with a 2.20 first gear 2.56 x 3.42= 7.52 overall ratio. A 3.42 rear with a 2.56 first gear 2.56 x 3.42= 8.75 overall ratio. This gives you better off the line and lower cruising RPM's
9.0 to 11.0 is right in the ballpark of where you want to be. So 8.75 would be close. Otherwise you're prematurely wiping out the clutch disc. Even if you rev it to 1500+ to take off, it throws heat into the disc. I've done a lot of research into this trying to figure out how to cut down my 60' times. With the M22W 2.52 first gear, I'm going to 4.10's to compensate. This works out to a 10.33 ratio. With 28" ET Drags, the car should get off the line a heck of a lot quicker.
So if I do install the Tremec TKO500 I have, I will be at 3.27 x 3.42= 11.18 and a .68 overdrive to boot.
Be careful about going too deep with the first gear ratio. You should be ok with 11.18 but too much more and you'll be in first gear only for a few seconds before you have to shift.
I went through the same questions when I wanted to save the # matching M-21. I built a new Muncie super case M-22 and am using 3.90 with a 28" tire. One of the benefits of the M-22 or 21 for that matter is 1st gear is stronger then the wide ratio because of teeth count on the imput shaft. Cutting the hole in the floor was out for me. Buick did the job years ago.
