To 5 spd or not to 5 spd

[Takid455]

I'm in a debate. I am trying to figure out what would be best swap for a long trip. Currently, I have a 74 t/a , 4spd, 3.42 gears, 455 w/ a fairly aggressive cam 242/252 @ .050 duration. I would like to take to the nationals, but 600 miles of highway w/ 3.42 gears will consume quite a bit of fuel not to mention the engine will be around 3500 RPM. (75-80 mph)

Option 1
change rear to 2.73. Already have another 10 bolt w/ 2.73's I build for last year's trek. Last year I had an auto car w/ a mild stall. I'm concerned about excessively slipping the clutch to prevent the engine from bogging from a start. car is a little jumpy at low engine speeds due to the cam w/ the current setup.

Option 2
change rear to 2.73 as stated above and locate a doug nash 5 speed. I like this the best, but has a greater cost. with a 3.27 thereabouts fist gear trans ratio, it actually provides a better ratio w/ 2.73 rears than the stock setup. no need to worry about slipping the clutch.

this swap will only be for long trips. car will be returned to stock after arriving home.


thoughts.....

[NOT A TA]

I switch back and forth between 2.41 and 3.73 rears. It gets pretty quick after a couple times. I don't even disconnect the shocks any more, just spin the lower plates out of the way. Use a mity vac to bleed the rear line and you're done pretty quick. Since you said most of the trip is highway how many times are you really going to be starting from a dead stop? I think the additional clutch wear would be minimal for just one trip per year and probably doesn't warrant buying/installing a tranny. Now if you're looking for an excuse to warrant the purchase thats a whole different story!

[Takid455]

.... Now if you're looking for an excuse to warrant the purchase thats a whole different story!

:):ssst:

I have become fairly quick at swapping rears. my last one was 2 - 2.5 hrs. I have always liked the 4+1 and wanted one. Was going to put one in my 78, but a T56 found its way in there. That car is not finished so I plan to take the 74. However, with $ being not what it was, I should hold off on the trans, but if it means less harm to the clutch and engine, i'll make an exception. I just did a full mechanical rebuild on this car over the winter. didn't plan on it, but one thing lead to another. I don't plan on many stop and go situations except for gas and cruising. maybe 2 dozen times. not terrible. I guess I'll have to hope not to get stuck in traffic. I think that is my biggest issue.

[Vegas69]

You're more ambitious that me. Change gears for a road trip? Buy a TKO and take a nap on the way. LOL