67mustang302

I doubt it'd ever get out of 4th gear though unless you have like 4.10's or more. I top 4th in mine with 3.55's at around 140mph and a 25.6" tire. You have to have a FAST road race car to ever see 140mph on a track. That's shifting at just under 6,500.

cmanf

If you dont think you will ned 5th go with a toploader 4 speed.
I had one in mine for years worked fine, I just re-did everything and used a TKO
Think his name is David Key but he has rebuild kits and is a toploder specialist.

kalli

well you must be suicidal driving 140mph with a stock 64-66 mustang anyway. so ya i believe as well the 5th is not needed. but the T5 are nice transmissions. if you have gears >4.1 you might as well just throw away the first gear of the T5 :-)

67mustang302

David Kee Toploaders. Definitely the place to get Toploaders and TL stuff.

And yeah, to even benefit from the use of a 5th gear, even a tight 0.8 5th, you'd need either a LOT of gear, in which case 1st becomes 100% useless and you might as well use a 4spd, or you need a TON of power in a light car, like 500+hp in a car that has a 3,000lb full race weight and be on a FAST track to get over 140mph.

_RY_

well I topped it out on my 1:1 3speed with 280 gears, so maybe I am suicidal
thanks for the info. I think Ill go with a t5 and 380 gears for now

67mustang302

At what rpm did you top it out?

And remember that on a road course, you rarely have enough long straight road to top the car out, it's not long enough, and you have to slow down to make the turn. You can try to top it out, but on most courses that usually results in slamming into something trying to make the next turn.

kalli

ya i'd love to know as well what rpm that was at.
4500rpm in 1:1 with 2.8 is 120mph (26" tyres), which is mighty scary in such a car.
it gets then lunatic at 5000 (135mph) and at 5500 already is where suicidal comes in (150+). if the car doesn't backflip before that

67mustang302

Like I said, in mine I've had it to about 6,200-6,300rpm in 4th with 3.55's and a just under 26" tire. Something like 140-145mph.

urban_cowboy

I too have been in the 140 range, but on a long straight away. I have yet to hit the 7000rpm chip in 4th gear, but maybe this summer at the Texas Mile event. I run a 26" tire with a 3.50 rearend.

Scott H.

Good point guys,
In the lower classes of HPDE the speeds are not even close to needing more than 1.0:1

Now if you get involved in racing, or want a car that is street and track, that's a different matter.