THoughts on running 3.31 gear with a 200r4 tranny???

I've ran the TA118 cam 228/247 with the 3.08 gears, .64 OD and 26" tire. Even towing a trailer in 5th gear at 1800-2000rpm wasn't an issue. But then again, I can do weird things with fuel and timing too.

 

Curious about tranny use (Re: Goal for 200-4R)

Dear Larry and V-8 Buick members,

Happy Easter everybody!

Okay thanks, yes what I was imagining is what other folks been saying. You need to look at your engine's performance curve, determine the lowest RPM where the engine can still cruise comfortably, then match your rear-end ratio so that you are cruising at highway speeds with that engine RPM.

I'm going to ask Jim Weise to review all my guesswork when he finally can look at my engine, but I had put a lot of design work around an engine using the TA Performance 212 cam. Depending on how it is set up, it can produce a very nice flat torque curve way down to 2000 RPM. I got a lot of help from some nice gearheads on the Team Buick forum. In particular, "Dr. FrankenBuick" ran some dyno2003 simulations for me: http://www.teambuick.com/forums/showthread.php?20059-The-quot-epic-quot-430-rebuild-caper! So, given that I'm trying to get a really fuel-efficient car, that will fit my goals.

What got me a little concerned was a comment from Jim about the 200-4R. He pointed out that it has a "mid-sized car" pedigree; thus, not really a heavy-duty transmission. So even with aftermarket hardening, it isn't best transmission choice for towing. So that's why I was wondering exactly why someone would change to even a hardened 200-4R in the first place. Is the interest in this tranny purely fuel economy or does it have other performance advantages that might not work well for my objective?

*Sigh*, two bad reasons:

Bad reason:
That was the car's original rim size . . . .

Worse reason:
When attempting to upgrade to front disk brakes last year, of course the old rims didn't fit. Given the choice of something ugly or spending some dough and getting reproduction Buick rally wheels . . . . :grin: Of course the fellows at Orinda Motors didn't suggest increasing wheel size at the time and - I didn't know about V-8 Buick. ou:

For towing the small wheels are okay, but it limits the size of disk brakes. At the time, I wasn't thinking about putting the car back into towing service. Given the amount of dough Jim is going to get from me, I think I'll probably stick with these wheel sizes and the available brakes. Eventually, I'll upgrade the rear brakes to disk. Then when I get myself something heavy to tow, I'll have to invest in beefy trailer brakes to keep the whole tow rig reasonably safe.

Oh well, hindsight is always 20-20!

Cheers, Edouard :beer

 

Re: Curious about tranny use (Re: Goal for 200-4R)

It is ridicoulous the abuse a gearvendors can take. Some people use them on the Baja 500(etc) races, and landing after catching air is BRUTAL on drivetrain parts, and from what I've gathered on those is everything else breaks before the gear vendors. Axles, pinons, driveshafts, transmissions, etc.

 

I detect a pattern here . . . (Re: Curious about tranny use)

Dear Larry, SilverBuick, and V-8 Buick members, . . .

Hmm, that's the same alternative that Jim Weise suggested to me when I mentioned the 200-4R plans . . . . .

Hey, you guys aren't all on commission are ya'?!?!!!! :laugh:

Seriously, I see the price penalty, but I also see the advantages. Unfortunately, the car has a TH350 in it now, so I would have to either harden that or swallow the conversion to a TH400. However, blowing a transmission on a road-trip could really ruin your whole vacation. Also the gear-vendor design is clearly much more versatile than just overdrive. So I'll need to go back and reconsider my transmission scheme.

Of course, when I had to replace the wheels - it turned out the 4 tires are completely worn out - so what did I do? . . . ou:ou:ou:ou:

However, when I replaced those tires, the idea was simply to keep the car running. This was before ideas of big-block Buick engines started dancing in my head and all the neat things I could do with the a car with "big muscles." So perhaps I won't do this immediately, but before I hitch up my wagon to a heavy load, I'll probably upgrade to more "assertive" tires that can better cope with that sort of duty.

So thanks on all counts. My wallet hates you all:dollar: but if I had found V-8 Buick last year, odds are I would have avoided some expensive mistakes! :af:

Cheers, Edouard :beer

 

Wow out of town after I posted the question and there is alot of feedback. I always felt the 3.73 was the right gear. I cant use the 3.90 because that rear is a 70 and the 3.31 and 3.73 are the narrower 66 12 bolts. I have the 3.73 in the car now and it runs fine on the road in low stall just to many RPMs for the way I want to drive the car. On the highway 75-80 is the cruising speed. In town it would be left in 3rd to avoid the lug.

Thanks for the valuable input and I have to say I have official seen the longest calculation for tire size on this post!:TU:

I changed my stock rocker arms to TA 1.60 rollers and had some porting done on my Performer and spacer. I am going to a Holley HP1000 and will have it dynoed in a few weeks so I will search for the sweet spot.

Thanks again guys and I hope everybody had a Happy Easter. I got to finally see a Twins game at the new Target field and they beat the Indians again!!

 

I want to go with the 3.73 in my 1964 but I can't find one. Can someone point me in the right direction?

 

I was able to find the 3.55 and 3.90 for $420.00 at OPGI. Jegs is much better. Thank you.

My tire size is 245 45R18. They are about 26.5 Tall. I currently have the 2.78 gears and 200 4R trans with a mild cam in my 300 ci. So, 3.55 for a cruiser?

 

I like your math. 3.90 it is. Thanks