65 Coupe Big or Small Block

[OldSkiBum]

I’ve decided that my next FFR build is going to be a 65 Coupe. I’m building the car to drive on the weekends around the foothill roads in Northern California. I know everyone has their opinion whether a big block or small block Ford is the better power plant. What I want to know from the guys who “designed and tested the car” is which fits the chassis best, which works best with the suspension and creates the best cornering and handling? I’m planning to build either a 427FE block or a 427 small block from a 351W block. What about torque and horsepower? Do I want to build my motor with more bottom end torque or lean toward top end horsepower? There won't be any computers or EFI systems installed in my build. What is the chassis designed for and what becomes over kill and a waste of money? I know more isn’t always better. I’m planning to run a TKO-600, close ratio 6-speed, and would like to know what rear end ratio works best with the design of the car. I would love to install the IRS upgrade but my budget screams 3 Link. I want to run pin drive wheels and have seen where roadster builders have narrowed the rear end to accommodate pin drive wheels. Will this work on the 65 Coupe? Thanks, Greg S

[Gordon Levy]

That is a bunch of loaded questions that don't have 1 specific answer. The easy one is go with the 427 small block as it will fit where the BB won't. We regularly make 600 drivable reliable hp with them. The car is 2400lb so low end torque is not really that critical. With the proper set up the car will work well with anything you want to put in it or do with it.

[ricobrafan]

I too am considering the coupe and while I have not considered a big block, I have compared the 302 versus 351 based engines. Gordon was helpful answering some of my questions. A recent post listed the new IRS in stock form being capable of 500 hp so your big block and 427 options are out without more costly upgrades. I think a 302 based block (maybe up to 363) is a wiser choice due to the reduced weight thus better handling. You did not mention track day or autocross use? If this will be just for street use anything over 400 hp is just a waste of money (IMO) but we are all building our dreams and the beauty is that he can all build what makes us happy and is within budget. Enjoy!

[Jeff Kleiner]

The FFR Coupe was designed around the small block (as was the original). While it is possible to build one with an FE doing so would require a fair amount of fabrication to the chassis, sheet metal, exhaust and body.

Jeff

[68GT500MAN]

There was only one prototype "Supercoupe" designed and built with a 427 FE (the body has a reverse tail and additional lights in the nose). I know of two FFR builds that stuffed an FE in them after much fabrication. I would go with the 427w.
Doug

[Garry Bopp]

One point about tranny ... the TKO 600 is a 5 speed transmission. I believe the T-56 is a 6 speed and it is a longer transmission. Therefore, the driveshaft is very short and would require you to use IRS, as the driveshaft is not long enough to accommodate a live rear axle.

Garry

[GoDadGo]

The TKO 600 is not a 6-Speed gear box, but five speed transmission that is capable of handling 600 lbs of force.

If you are looking for maximum power at minimal weight then maybe an LS engine might be of interest to you. Chevrolet Performance LS376/515 (LS3 6.2L 515HP) can be had with a T5/6 for around 12-K. The engine is all aluminum and quite compact. They make a version of that engine that has a front drive distributor so it looks like it could be a Ford piece.

Most people want Ford power plants so please don't take offence to my comment. Just trying to give you options that gives you the most power at minimal weight, for the least amount of money. Take Care & Good Luck On Your Next Build!

[OldSkiBum]

Oops, Sorry about the typo. Yes the TKO 600 is a 5-speed transmission that can handle 600 foot lbs of torque, I had one for my 33 hot rod. It sounds like the motor for me is going to be the 427 small block from the 351W. I plan to build it with 500-600 hp, with the TKO-600 and the three link with around a 3.07 gear ratio so cruising down the freeway will keep the rpm's down and the motor rumbling. I've been a big block Chevy guy most of my life and so it is hard to cross over to something else, but if this is what the chassis and car was designed for I have to go with it. I don't plan to race or autocross my build and plan to cruise to car shows and drive it through the curving foothill roads throughout northern California. Thanks for the input, Greg S.

[Gordon Levy]

If you have an engine that makes that HP the cam will be way to aggressive to cruise below 2000 revs. I am dealing with a customer that did a 427W that dynoed at 550 and a 3:08 gear and we are changing it to a 3:55 because he can't drive it at low revs.