Powerglide or 3-speed?

[lake_harley]

I'm gathering information and parts to build a mild, low HP FED for bracket racing....well actually more for the fun of the whole process. I had always expected I'd use a Powerglide but recently became aware of the TH200 (non-lockup and non-overdrive) that is the size and weight of a Powerglide, supposed to rotate more freely than a PG, and in a light car, according to what I've found, it is capable of handling the expected 240-ish HP of the carbureted 283 Chevy I'll be using.

Regarding transmission selection I have several questions on what transmission would better serve a light FED with low HP? It seems the addition of the 3rd gear would be a distinct advantage to keep the engine in the power range a bit better and also offer a taller (higher numerically) low gear to get off the line. One opinion I've read though adding to my confusion is that the 1.86 or 1.76 low gear Powerglide would come off the line a bit softer with less wheel spin because of the numerically lower gear, compared to the TH200's 2.54 low gear. Also in consideration is that right now I have an opportunity to pick up a reasonably priced TH200 as a core, but also thinking because of the popularity of the Powerglide for so long, more performance oriented parts are likely available at reasonable cost. Keep in mind I'm looking at a very mild 240 HP carbureted 283 Chevy, not some 600+ HP engine. I'd like to get a transmission picked soon because it would be key to laying out the engine, transmission and rearend with an alignment bar to get started on construction.

Needless to say for bracket racing consistency is what I'd be seeking and wonder how that might play into the 2-speed vs 3-speed transmission selection. Also, FWIW, for rear tires I'm thinking a 29/9.00 - 15 tire might be about right for the car and I'm estimating weight at about 1400#.

Thanks, in advance for any guidance!

Lynn

[THE FRENCHTOWN FLYER]

Man, I think there is a reason so many bracket racers use the 'glide. Like the 9-inch Ford rear end, it just offers so many advantages to outweigh the disadvantages that I think the PG is your best choice. Your converter can determine how hard the initial hit is and only having one gear change is a plus to me. Parts for one can be found everywhere from Walmart to classified ads.
I also like your choice of a rather smallish tire. I think it will work well with a 'glide.

What does your engine combo look like? HP projection? 

[lake_harley]

Engine will just be a flat-top piston 283 with 58CC 305 heads...so about 9.1 compression, and a very mild cam. Likely just a Quadrajet carburetor on a Edelbrock Performer intake for now (since I have them), but it HAS to have zoomies since it's a FED, even though a 4-into-1 longer tube header would probably make more HP. 

SWAG on HP is about 240-ish or a tick over. I've always heard there are a lot of "300 HP" engines out there that in reality are more like 250 HP, so I think I'm being realistic.

Rearend I have, and I'll be narrowing it myself, is a 8 3/4" Mopar with a 3.23 gearset for now. That gearset is what had me thinking I'd maybe benefit from the steeper 1st gear of the TH200 3-speed. I guess in though in reality ET doesn't really matter in bracket racing as long as it's consistent.

Lynn

[Paul New]

We ran a 3 speed with low HP engines years ago.  It worked good

[masracingtd1167]

In it's stock form the 200 is not really a good trans ! Some of the Comp guys are using them behind a 4 cyl engine but with a lot of expensive parts ! A glide is still the cheapest way to go !

[lake_harley]

I understand that the TH200 isn't highly regarded and don't know how significant the modifications might need to be for a 1400# car with 240-ish HP. The website that I saw, Scott McClay's, showed some pretty significant cars but perhaps it's a bit presumptuous to think they're all running TH200 transmissions?

Paul...I'm curious what kind of 3 speed did you run? Did you feel the extra gear was helpful? How was it at the line with what kind of car and engine? What about the possibility of excessive tire spin at the line? With such a mild engine it may not be an issue at all?

FWIW...I have no plans to run a trans-brake, feeling that foot-braking it would be much easier on everything. Is that just folly on my part?

Thanks for the comments everyone.

Lynn

[crider]

I agree with low HP and the very mild 3.23 gear a 3 speed transmission would be a help, I'd leave that 200 alone. Parts for it going to be pretty pricy to do any upgrades. I'd just grab a TH350. The savings on parts will likely more than offset the difference in the cost of the core transmission

[lake_harley]

Thanks again everyone. Funny how after being around all kinds of cars my whole life, and I'm 68, when it comes down to fine points and details I realize just how little I know.

Stay tuned for the next noobie question(s) on building a FED. Just to be clear, I do consider myself a competent fabricator & welder and had a fabrication business for about 15 years, which I started from the ground up.

Lynn

[JEFF/21C]

I would try running the th2oo, the torque convertor will depend on the cam used i've used stock convertors, a c3 torque from a pinto in a c4 behind a 289,that would pull the wheel off the line a 4 cylinder chevy 2 convertor in a powerglide behind a 327 chevelle that would  ran 13.00s and was the tow car for my race car.  the 29x9  on 8" rims  will workout well because of the weight would run alot more gear about a 4:10 you will not get too much spin because of the rear wheel weight bias and a 283 doesn't have alot of torque

[lake_harley]

Paul New....I sent a PM to you about something not directly related to this thread. Wanted to mention it here in case you don't see that you have a new PM. I know I forget to check for them.

Lynn

[Paul New]

We ran a turbo 350 with a 292 6 cylinder in the early 80’s

[THE FRENCHTOWN FLYER]

Years ago I decided to build a Sportsman e.t. racer that was waaay out of the norm. Just because. I chose a 300 Ford six, a 1.82 Powerglidew/ 4000 stall converter and a 2.47:1 nine inch rear end. This puppy would hook in a mudslide and was deadly consistent. In one 18 month stretch I was in 12 final rounds, won nine of 'em, and two class championships. Several efforts were made to outlaw this car or get it banned.
Point is, if you want to extract every last tenth of an elapsed time a 3-speed will work best with a low HP powerplant. If you want to win rounds a Powerglide is all that is needed and what I prefer.

[lake_harley]

Point taken! The point you made earlier in this thread about only one shift with the P-Glide is one that my more-than-likely driver made too when we talked last evening.

Lynn

[JEFF/21C]

just to clearify when I used stock convertors was in the 60' and early 70's as after market convertor were few and far between my first was a FAIRBANKS 8" that would flash to 6000 rpm in a 3600lb, 327 powered  car and most of the cars i've built had power glides  with everything from a 9.5" on a blown sbc to a 7" on a 306" sbc. I like trying new things and try to do on the cheap so if it doesn't work just revert to the tried and true

[retroboy]

Mate I use a 904 TorqueFlite with a 2.45 1st gear and a 4.33 rear. I launches like a rocket which was initially a problem as it would hit the wheelie bars hard and unload the tires then chuck me off the gas pedal. Sprung wheelie bars seem to have helped. There is a fair RPM drop on the one two shift( 1.45 2nd gear) but I'm running on a dial in so it doesn't matter.