Stock Auto Trans Rule Change History ?

[Mark Yacavone]

Originally Posted by Stan Weiss

Mark,
Who makes these ratios?



Stan

Not sure who makes them but Coan and Pro Trans offer several.
To be fair, McClay 200's have some ratio options but he's at the higher end of that style.
He won't sell parts to the public. You have to have one of his transmissions.
Leo G at Remac will sell you a 2.91 planetary for the 200.

[Stan Weiss]

Mark,
Thanks for that information. I knew that McClay offered a 200 with a 2.91 and Rossler offers a 400 with 2.97 and Coan a 400 with 2.96. I had not heard of anything lower.


Stan

[Henrys Toy]

Originally Posted by oldskool

Just curious, were most PG users quick to change over ?

Or, were there a lot who wanted to stay with their PG ?

Were there some of the heavy hitters that did a lot of testing, before switching over ?

It just seems like this was one of those major Stock rule changes, & since I was not involved, I wonder how big of a deal it really was, for the PG racers, back when it happened.

Good afternoon,
I think I might have been the last hold out in H/SA. I took the Glide out this year at Numidia after I lost at the points race. I installed my McClay 200 and Munsinger converter. This was by no means a back to back test. The car was geared for the three speed from the beginning of the year. The car went from 1.54 to 1.56 60 ft.'s to 1.44 to 1.46 60 ft.'s . In all honesty the car probably picked up a tenth. I can tell you from sitting in the drivers seat racing against another H car with the three speed, they would pull out on me and once I got going they didn't drive away from me. They were at least a half to almost a car length on me in 60 feet.
I thought I could over come the deficit with torque but that never materialized. My car hooks very well with both transmissions , it is certainly easier to race with the Glide. I did so for almost 40 years. So as you might imagine, it takes a little getting used to the launch of the three speed. Plus getting used to the new shifter, but we've made improvements.
The converter and transmission testing and "red" T- Shirts will be starting over again next season. I don't know if this answers your question, but let me know if I didn't get you what you were looking for.

Respectfully,
Henry Kunz 1534 H/SA

[oldskool]

"...In all honesty the car probably picked up a tenth..."


So, for others reading this who also made the switch from a PG to a 3-speed, after you got the whole 3-speed set-up tested, tuned, & finalized, did you also realize an aprox "tenth" ET improvement ? Or ?

Again, I'm just trying to determine, from actual racers who made the switch, as close as possible, how much quicker a 3-speed is than a Glide, in the same car, same class. Obviously, this is comparing top quality pieces, matched to the car, fully tested, tuned, & optimized.

Just from what little I've learned from this thread, it seems that the larger gains are realized from the lower power, lower torque engines. Is my assumption correct ?

With this in mind, would the 2-barrel version of an engine likely gain more from a 3-speed conversion, than for the 4-barrel version of that engine ?

[Gmirza]

Originally Posted by MR DERBY CITY

Sorry George, but you are WAY off …..

I know it was around this time they allowed a 904 in place of a 727 behind a 340. Any corporate transmission that could bolt directly to the engine was allowed.

[MR DERBY CITY]

Originally Posted by Gmirza

I know it was around this time they allowed a 904 in place of a 727 behind a 340. Any corporate transmission that could bolt directly to the engine was allowed.

George, I know NOTHING about Mopars but,….you are replacing one 3 speed trans with another 3 speed trans. The OP would like to know when the GM guys could replace their 2 speed trans with a 3 speed trans. And it was WAYYYYYY after 1990….

[Jack McCarthy]

ok i know the answers ....
i got the turboglide approved as a 3 speed for 58-61 chevys in 2010 i believe was a struggle as i also had to weigh one show it was close to cast iron PG it was 9# lighter full of fluid ... then within a year nhra opened the flood gates and allowed any GM trans.

turbo 2.75 was about .10 better after 3 converters
291 metric is .10 better than that good 350

i weigh 4500 lbs FYI

captain

[jmantle]

Originally Posted by Stan Weiss

Mark,
Thanks for that information. I knew that McClay offered a 200 with a 2.91 and Rossler offers a 400 with 2.97 and Coan a 400 with 2.96. I had not heard of anything lower.


Stan

Protrans offers ratios down to 3.20, I assume they are all based on a 904 style gearset
http://www.protransracing.com/images...IO%20CHART.pdf

[Dave Noll]

Originally Posted by oldskool

With this in mind, would the 2-barrel version of an engine likely gain more from a 3-speed conversion, than for the 4-barrel version of that engine ?

When I got a gearset from ProTrans I talked to the owner of the company. I got a set for my 2bbl Cleveland Cougar's C4. He told me how to drive the car with the new set Then told me that there were WAY faster cars than my "N" stocker that were running fast with a Steeper 1st & 2nd than what I had just bought. He didn't give me #'s. For mine I made more than 1 change when I installed the gearset but my car is quicker now.

[oldskool]

"...in 2010 i believe...then within a year nhra opened the flood gates and allowed any GM trans..."

So, 2-speed GM cars have been able to run a 3-speed now for just over 10 years.

Anybody here disagree with that ?

So, for you guys who race a full schedule, including nat events & div races, AND are familiar with LOTS of Stocker combos, do any of ya'll know of any Buick, Olds, or Pontiac models, which came with the 2-speed Super Turbine 300(IIRC, Olds called it Jet-a-Way), which have been actively racing in Stock, in the past 10 years ?

For you older guys, who were running a full schedule back in the late '60's or at least by the mid '70's, what year was the last time you saw, or knew of, a SERIOUS '64-'66 GTO Stocker, running an auto trans ?

The reason I ask, besides just my being a Pontiac Freek, is because the 2-speed BOP trans I mentioned is the only auto trans that was legal for those cars. In the mid '60's, there were lots of 4-speed GTO Stockers, especially the Tri-Power models.

But, I have only run across 1 pic of a '64-'66 auto trans Stocker. It was a '64 model, named "Lil 2 Speed". From the markings, looks like it was running either AHRA or IHRA.

A few of the big Pontiac dealers ran some pretty quick 4-speed GTO's, especially the Tri-Power '66 models. But, if I've seen one running an auto, I don't remember it. I just ASSUME this is because of the 2-speed.

Apparently, those 2-speeds could be built strong enuff for Stock Elim duty. My trans guy said he could easily build one that would hold up behind my 455 bracket engine. And, I think the TH350/400 converters will work in the non-lock-up 2-speeds.

Hey, I haven't even ran across any info indicating that a competitive '64-'66 GTO, of any kind, ran Stock in the '70's & later. I suppose that most Pontiac guys moved up to '67-up 400/455 powered Birds & Goats, with Q-jet carbs & TH400 trans.

If any of you guys have any info, or insight into this, I'd appreciate hearing it !

Below is the only pic I have of a 2-speed GTO Stocker.

Edit: Well, I decided to look back thru my '64-'66 GTO pics, to make sure I hadn't overlooked an auto trans Stocker. To my surprise, I DID find one. On the rear fender, it even says it was an AHRA nat record holder. The reason I haven't used this pic very much is because it appears to have a Tempest grill, rather than a GTO grill. So, I assumed it was probably not legal & only ran some local outlaw track. I never even noticed the "AHRA Record Holder", until tonight. By chance, does anybody here know anything about either of these cars ?