I don't know about you big horsepower big block guys, but I've got a 700R4 behind a 402 big block in my pickup. I tow a 6000 lbs trailer with it everyweek and been doing it for over 3 years without any trouble at all. I know the guy who built it put some later model pieces (L65E i think) in it. I told him about the long hill I pull with the trailer and he said "just drive it in overdrive, it knows when to downshift". He's been right so far.
I've got 3.07 gears behind my 700r4, with a 28" tire. I can cruise on the freeway around 2000rpm, keeping up with modern traffic really easily and knock down really good gas mileage. - On the way down to paso robles and back, doing 80mph I got 19mpg. The 700R4 has a steep 1st gear, so with all of that big block torque, why not make it last a little longer speed wise and knock down some decent mileage with some 3.23 or 3.08 gears?
if you go too tall of a gear you'll be lugging the motor. I run a 700R behind a 425hp 454 crate motor with 3.42 gear and 255/60x15's that gives 2000rpm at 70 mph. I flogg it and haven't had any problems and I've got 18,000 mi on it.
Lugging the motor may not be as big of a concern as having it downsift too much. If you live in flatland, it should not be a problem...but we have hills out here in AZ and steeper gears work better with overdrives in heavy vehicles. Really you need to get it running and see how it works.
I have a 700r bolted up to a 454 gen5 big block watch the flex plate you'll need one from one of the tranny co.s
I have a 454 in a 1-ton four-wheel-drive with a turbo 400 and 4.10 gears. I find it very pleasant to drive, but it rarely beats 10 mpg, and pulling a trailer it drops to 7 or even 6. I love the way it accelerates when I want to pass on the freeway. Push the pedal and it jumps. I'm building a '54 Chevy 1/2-ton planning to run a 454 with a turbo 350 and 2.29 gears. The rear and transmission are from a car that ran a 305 and weighed about the same as the pickup. I drove the car, it wasn't exciting, but was acceptable for a driver. I'm hoping to get 12 around town and maybe 15 highway mpg while having the cache and performance of a big block. I've threatened to tell people its a 427 but it is a 454. It should be 2,000 pounds lighter than the 1-ton...
if they can't spot the bigger 454 damper then let them believe it's a 427. 2.29s is pushing it...but it will be nice on the highway....
Mines lugging below 45mph. I went to a seminar put on by Empire Driveline and they stated that they have been seeing a lot of u-joint and output shaft problems which they trace to to tall a gear being used with OD trannies and the motors lugging. They advise to not use OD under about 1800rpm's. Seems as though a lot of people asses are clueless for understanding what's happening. Another way of putting it is they don't have a feel from the seat of their pants as to what's going on
My ride had a 400 in it with my 454 Chevy BB 426. Its cool to run if you are not going to do a ton of high speed highway driving because you lose the overdrive benefit. Now I run a 400 with the 454 Chevy BB zz4 crate motor (which is a whole other story) and its cool.Put about 5000 miles on it each summer around here. I havent found anyone that could build a 700R4 strong enough for me- only reason why I havent tried it.
Does this mean you've never had a 700 behind the motor or that you wrecked one? Is this a ZZ454 as the ZZ4 motor is a 350? If it's the ZZ454 you're only pushing an advertised 15hp more than mine. As I said I've had no problems in 18,000 mi. I've got a friend who has one behind a 350 that had his go out in 12,000 mi it apparently wasn't locking up in OD
ZZ454- havent had muy coffee yet. I never put a 700TR4 behind it. USed to have a 350 before the 400.Loved it but got an opportunity to get the 400. Just got me thinking that maybe the 400 might have something to do with my new motor overheating all the time- not that it is directly related but maybe in the grand scheme of things along with the thermostat, carb and every other picee of shit attached to the damn thing- maybe something in the tranny is screwing it up. Once the car comes back from storage this winter gotta check it out.
My SS454 '90 pickup came from the factory with a T375 and a 3.73 rearend. Basicly the combination is/was a dog (all show/no go). I had my favorite automatic transmission man build a 700R4 for it and I couldn't be happier. I can cruise th X-way now without fear of driving over the crankshaft (less RPM) and it's easier on gas to the tune of about 2 1/2-3 miles per gallon. Frank
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