i have a 1956 oldsmobile 88 hardtop and plan on putting a 455 old engine in it and want to put a 700R4 transmission on it..what adapters and other stuff will i need and trans mounts to do this..and will it fit im my car..thanks
JEGS sells a kit, BOP to 700R. You could use a 200R and beef it up to suit your BBO. Art Carr builds them tough. I believe you can get a BOP patterned 700R from Cadillacs, full size Olds 88 wagons and some Delta 88s.
Ive done the 455 into a 55. I also have a 700 to go behind it, but it has a T400 atm. Pm me your email and i can send you some photos of what I did for the motor install and brakes stuff.
700R4 are only Chevy bellhousing pattern, so you need an adapter to use behind a B-O-P-Cad bellhousing. I agree the better solution is use a 200R4, it will bolt up direct. They are also slightly smaller than a 700R4 so it will be an easier fit. Some 200R4 are dual Chevy and B-O-P-Cad bolt patterns, others are Chevy or B-O-P-Cad. Just make sure you get one with the right bolt pattern to bolt up to your Olds 455.
Most 200-4r are 'multi bell' (BOP/chevy), a small number were BOP only. None were made for Chevy only, so any 200-4r will bolt up to your engine. C-K Performance in Holtsville NY probably build the best 200-4r in the country and also sell the flex plate, torque converter and TV bracket and cable needed to install the trans. A good cross member to use would be a late model Lincoln one (I forget the year, check a salvage yard) It is a double hump design, good for dual exhaust, tho you may need to relocate the mount pad for your application. If you are really set on a 700-r4 CK build them too. www.ckperformance.com
Just a thought here. I know the "in thing" is to go for an overdrive trans, and in many cases, it makes things better (both acceleration and highway driving/mileage). But do you really NEED one with the 455 Olds? they put out TONS of torque, so a highway gear is still acceptable for accelerating. And will give you a good highway gear ratio, and decent mileage. A good friend had 56 Merc, on a Grand Prix chassis, with a 455 Olds and T-400. Must have been highway gearing (2.72-3.08), because we did a lot of traveling together, and both he and I got 20-24 MPG on the highway. Mine was a stock 55 Olds driveline.
Whether you use a 200 4R or a 700 R4 , you must make provisions for lock-up converter control. Both units rely on lock-up in order to get full cooler flow and thus full planetary lubrication. There are several ways to do this, but the easiest way is by using a pressure switch on 4th gear pressure port on valve body. We have used this with good success on many conversions.
One thing if you go to an OD transmission you will need to raise the diff ratio up to 3.5 or 3.9 ish to get the benefit of OD otherwise it will be a slug and labour around town. Low OEM ratio 3.00 or whatever will defeat the purpose of an OD transmission.
Chopolds is right, my 56 has the original drive line and goes down the highway great at 70. I think the overdrive may be too sluggish at lower speeds. But requardless I'd love to see pics of the build........john
seems the 700 is the mid size between the 400 which most people put in and the 200... if i go with the 700 am i gonna have to cut some of my x frame out to fit it?
This bolt pattern marking is in error as follows. On the verticle row of three on either side, the topmost is Chevy only....not used at all on BOP. Starting up the 'slope' the next bolt is BOP only....not used with Chevy pattern. Ray
The 700R4 is 30" long, only one inch longer than the common short version of the 400 at 29". I tend to believe a 700 will go in any space that would accommodate a 400. Ray
sluggish at lower speeds? How is that even possible?? The 200 4R has a lower low gear with the torque of the 455 you'll be off like a "rocket" Once moving whats the difference?? think about it..
700R4 has a lower 1st gear (3.06) than a 2004R (2.74), but you are correct, the torque of a 455 is more than adequate for virtually anything put behind it. As for the OD being 'sluggish' at low speeds......they are called 'automatics' for a reason....they shift themselves as needed. OD doesn't even engage until about 45 mph and will disengage above that with increased throttle application. Ray
If you use an adapter plate get the thick one, About 3/8 thick not the 1/8 thick one cut out with a water jet or plasma. The thick one should have a spacer to go in the end of the crank to space the converter snout back too. I've had both and the thin ones tend to flex.
I think the "sluggish at low speeds" is probably an issue that some guys have is they put in an overdrive trans, with a highway gear. When traveling at "lower" highway speeds,. the car is in overdrive, but the RPMs of the engine is really too low for pushing the car along, causing RPM 'hunting' and sluggishness. I've been in cars where this is the case, and the usual fix is to put a switch on the overdrive, kind of cancelling it out during some speeds. Then the OD seems like a waste, unless you are really travelling FAST.
The good with od trans is that the engine is runing slow at high way speed I have a TH2004R on my olds with a 455 i have 3.08 posi in the rear end And it's posible to burn tires in high speed if lock the gear down manualy It shifts up with the kick down already a 3900-4000 rpm (the 455 is modifed a lot)
Neither a 700R4, nor a 200-4R have an electrically controlled overdrive. In both cases, the overdrive gear is 4th, like every other gear. The only electrical portion of the transmission in either is the torque converter lockup feature, which overcomes the inherent inefficiency of a torque converter, which its inability to have a true 1:1 throughput, by locking both the input and output sections together. From the factory most 700R4's and 200-4R's are setup to only activate this feature in 4th gear. I have seen a few where they were set up to do it in third, however, in my experience, they are rare. ALL of the aftermarket kits, that I have seen, for torque converter lockup control allow this to occur in 4th gear, only, with some adding override when the brakes are applied, or when engine vacuum increases (throttle blades slamming shut). In any case (save for the rare 3rd lockup gear models), the moment that the transmission is out of 4th gear, the converter is unlocked, period. Unless the transmission was built wrong, or is operating in a degraded state, you will never be in overdrive at lower speeds. If the overdrive seems like a waste unless you are travelling really FAST, then the car either has the wrong transmission (wrong ratios), the wrong rear end gear ratio, or both. There is a science to choosing gear ratios. Simply grabbing a pile of junkyard parts and cobbling them together will likely not end with the best results.
If you eliminate the computer to control lock-up, you usually run a pressure switch, to turn the lock up on in 4th gear, at a certain pressure. The electrical part of this is usually run through a brake switch, so when you hit the brakes, it cuts off the voltage to the pressure switch, hence to the lock up. In some of the cars I've had, the OD kicks in at a pretty low speed, in 4th. Not usually a problem, but if the gearing is numerically too low, it will have the problem I described. The quick fix most guys did was to add an additional toggle switch inline with the brake switch, to manually turn it off when this happened. Maybe some kits had a pressure switch that turned on at too low a pressure? Yes, I agree with you that you really have to figure out your trans and rear gear ratio to have it work out right!
I can understand why. I had a 350 turbo transmission in an off-topic truck that had the lock up converter, and when that converter locked up it felt like the truck has shifted into a higher gear. Posted using the Full Custom H.A.M.B. App!
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