455 in olds delta 88

[Racincc85]

I was thinking of buying a 1985 olds delta 88. I don't want to keeps the stock 307 engine and the Th200r4 tranny. I would like to swap to a 455 engine and a th700r4 tranny. Will the engine and tranny just drop right in and bolt up or will i have to make modifications?

[drdisque]

you will have to find custom big block engine mounts for that chassis and get a custom driveshaft, but you'll probably want to trash the entire rear-end anyway.

[Racincc85]

Would i have to fabricate the mounts or is there a manufacturer that would have them? Also, will the tranny bolt up to the crossmember that is already on the car or will i have to custom fabrication on that as well? Also, does anyone know the body code letter for this car and if the olds 455 will bolt to the th700r4 tranny?

[RandomTask]

I would imagine you would have to do some cutting into the frame rails to get a big block in there. Parts for a 455 are also a lot more expensive and would turn it into a costly project. I would probably build a strong small block, stroke it and bored it. That way you could drop your 700R4, or maybe a TH350 or 400 in. As far as mounts, I think you can get away with normal ones. I'm not too familiar with the 200R4, but I know the 700R4, TH250, TH30, and TH400 have similiar bolt and mounting patterns. Just remember, its still a Delta 88, you're going to put a motor in a car that is pretty overweight. Good luck, let us know how it goes!

[curtis73]

Its a B-body. Swapping to a 455 (provided its an olds 455) is super simple. The only external difference between small block and big block Olds engines is deck height. You may have interference with the hood and the valve covers may contact the brake booster, but that can all be measured first.

The motor mounts are the same, oil pans interchange, and all accessories bolt up directly.

You'll run into extreme difficulty finding a 700r4 with the BOP pattern. You'll either have to run an adapter or scour the internet to find that very rare transmission. My suggestion is to spend the cash on the 200-4r and build it up. There are some common misconceptions about the 200-4r. It is not designed to take massive torque (which is unfortunately what your 455 will produce en masse) but as far as a high-hp thrashing they are far stronger than their 700 cousin. Much stronger input shafts and a better valve body contribute to higher stock line pressures and a much longer clutch life. There are companies like Raptor that build 200-4r trannys to take well in excess of 600 hp. There are three other benefits of the 200 family; better gearing by far, lighter weight, and the lockup converters are a much better design than in the 700.

If you're not going to do any neutral drops and drive it like a civilized human, the 200-4r is the clear choice. If you need it to survive in towing or consistent high-torque applications, I might consider an adapter on a 700.

If you visit sites like B&M or Transgo they have pages listing all transmissions and their dimensions. The nice thing about GMs and their engine/tranny combos is that the frames were the same. If you look at the frame around where the tranny crossmember mounts you'll probably see several holes designed for the other trannys. That car as a Chevy Caprice used either a th350 or a 700r4, each of which were different lengths. Same goes for motor mounts. The crossmember would be drilled for either Chevy, pontiac, or olds motors.

You may also want to consider not ditching the 307. It is a factory roller cam. Its weakness is the 7A heads and pathetic intake. Get some 5A heads, maybe headers, a mild Lunati roller cam, and an edelbrock intake and you're looking at a pretty mean 5.0. I'm also not a big fan of the Olds 455. Long stroke and small bores hurt air flow. It will obvioulsy make more power than the 307, but it will also suck down a lot more fuel to make the same power.

Have fun and let us know how it goes

[RandomTask]

Yeah, what he said...

I suggested cutting the frame rails if you wanted to keep it all under the hood.

www.crossmembers.com
I think they only make for G body, but give them a shout, I'm sure they could help you out.

[Racincc85]

curtis73, thanks a lot for all that info. I'm new to the car scene and really appreciate that help. I still have a few questions though. What engine would i be able to find the 5A heads on, and should i stick with the GM quadrajet carb or get a edelbrock?
Also, what engine sizes did olds produce? I like your ideas about staying with the 307 but id like to explore other engines as well. Thanks again for the help!!!


P.S : Where can i find out what transmissions will bolt to what engines without an adaptor, just for the sake of gaining more knowledge?

[curtis73]

Found a few websites in my favorites on the 200-4r and the Olds engines.

http://www.transmissioncenter.net/Tr...asurements.htm

http://tech.oldsgmail.com/

http://www.realoldspower.com/phpBB2/index.php

http://www.mondello.com/

http://www.442.com/oldsfaq/oldsfaq.htm ... An excelent resource for the olds engines

[Racincc85]

Thanks for those links. I think i've finally made up my mind. I'm going to go with the 403 so i don't have to mess with cutting the frame, etc to get the engine to fit right and so i can still mount the A/C compressor in the same place ( From what i found the 403 has the same mounting locations for all external accessories as the 307 does). I can also keep the computer with the 403 I'm going to also stick with the Th200-r4 tranny but build it up as strong as i can. Right now I'm trying to save up some money and locate a car with a frame/body that isn't rusted out ( I'm contemplating ordering a new frame and bolting it to a decent body). I'll keep this post updated as i slowly progress lol.


If i do decide to get a new frame, would i be able to order one from gm or would i have to look somewhere else?

[RandomTask]

I wouldn't imagine GM would have any frames for that car, they stopped producing full framed cars in the 80's, (I think the monte carlo was the last car to have a full frame). If you're lucky, may be find a NOS frame. However This is something I wouldn't have that much knowledge or experience in.

[Racincc85]

Thanks. Do you know what year they started putting overdrive tranny's in the delta 88?

[curtis73]

Actually, RandomTask, they continued full frame cars until 96 when the last B-body rolled off the line. You were just testing me right?

With certain exeptions, the B-body frame like you Delta has didn't change much at all over its years. I won't go as far as to say they are interchangable, but I know the suspension trailing arms on my 96 impala have the same part number as your Delta. Many things like brakes, spindles, control arms, fuel tanks, and crossmembers are identical or interchangeble, even though the bodies changed. Suffice it to say that ANY B-body frame (not wagons... different frame) before the rounded body styles came in 91-ish will be interchangeable. Confirm that with someone else first before you buy, but I'm pretty darn sure of that. There were subtle differences, like for instance Buick bodies had some droning problems so they added an additional cross piece in the back under the trunk to cut down on resonances.

You won't be able to get a new frame from GM. You might be able to find a specialty aftermarket frame manufacturer that will build you one to spec, but you're looking at insane dough there. Find a good junkyard frame that's not too rusty, have it sandblasted and painted or powdercoated. Rarely you'll find a frame with some parts rusted through. G-bodies like Elcaminos and Cutlasses were notorious for this, but its easy as blasting it and welding in plate steel over the holes. The end result can be stronger than the original if done right.

Olds built a 215, 307, 330, 350, early 400, late 400, 403, 425, and 455. Ther were other ones but we won't worry about them The 215, 307, and 403 are the small. The 400, 425, and 455 are big blocks. Your swap to a 403 is an excellent choice. Big bore, short stroke, nice power, and externally identical to the 307.

Overdrive trannys started in 1981; standard on all 98 and regency, standard on all 88s with the 307. Finding which trannys fit where is pretty simple so I'll just spit it out here.

The old three speed autos fit into two families; TH350 and TH400... and they fit using one of two bellhousing patterns; BOP (for buick olds pontiac) or chevy. The 350 was the medium duty and the 400 was the heavy. The TH350 was later redesigned to add the overdrive. About the same time, the THM200 3-speed (and its lockup version 200-C) and the THM200-4r was created (M is for metric) as a small lightweight tranny to combat parasitic losses and keep fuel economy up. Up until this point, all 350s and 400s were cast in both the BOP and chevy patterns depending on which engine was in it. After 81, you had several options for trannys, and if GM had made different casts for all the trannys in both bolt patterns it would have been costly. The decision was made to cast the metric 200 family in a dual pattern case. The holes are there so that the metric trannys can bolt up to any GM engine. The 700r4's however remained only chevy patterns.

There are exceptions. I had a metric 200 three speed behind a chevy 305 in an elcamino that was a chevy-only pattern. There are also rare occurences of BOP 700r4's but you most likely won't find them unless you're looking really hard. On the website I had given you earlier, http://www.transmissioncenter.net/Tr...asurements.htm , you'll see under each tranny's heading it says, "bellhousing pattern; BOP, chevy, fit all". You need a tranny that is either BOP or fit-all.

Later transmissions came along, too. The 700r4 became called the 4L60. Its technically just the same thing with a different name. Starting in 1993, they were electronically controlled by the computer and called the 4L60E. Externally identical to the 700r4. The "E" transmissions can't be run without the computer.

The TH400 was also redesigned for a 4speed and went directly to "E" status. There is no 400-family four speed that is not electronically controlled. The "E" heavy tranny is the 4L80E. Again it can't be run without a computer.

Your only other choice for "bolt-in" tranny in your car is the TH350 with a BOP or fit all bellhousing. Which you could do by moving your tranny crossmember forward a couple holes in the frame, but its a 3 speed. As you can see from that website the 350 is the only one that shares overall length with the 200-4r. Any of the other trannys you'd have to either shorten or lengthen the driveshaft.

You may wish to do yourself a favor. One of those websites above that I gave you has links to which 200-4r tranny code was used in certain vehicles. There are some in bold type and they were equipped with better valve bodies and governors from the factory. If you modify your 403 to breathe a little, you may want to either get one of these trannys marked in bold (they're easy to find) or modify your current one to perform similarly. The stock 200-4r you have is a touch lazy and might have some frustrating shift points. If you don't build it up at least some, it will have a shortened life behind the bigger 403. The guts of the tranny will hold, but the extra power will eat the clutches if you don't improve its shift performance. Read up on those mods at the 200-4r tech pages I listed above.

[MagicRat]

Curtis is mostly right, except one can get aftermarket electronic controllers to install a 4L80E in a non computer car.
I installed an Olds 455 into an '81 Fleetwood. It was really easy. The Fleetwood frame is identical to a Delta 88, except the wheelbase is a bit longer. Under the hood its identical.
IMHO as you are going to do this project seriously, GO FOR THE 455!!. A pre-71 455 is best. It has much more performance potential than a 403.
It fits exactly the same as a 403, with the same engine mounts and bellhousing, except its approx an inch wider and an inch taller. However, there is still plenty of room to spare, with lots of hood clearance and lots of room between the frame and fenderwells. Enough room for me to install big, fat headers.
I used the factory THM 400 trans in mine.
A 700 R4 would be nice, but you can easily use a BOP pattern 400 and locate a Cadillac trans mount from '77 to 81, and it will bolt right in.
I also used the stock Olds 455 mounts. They lined up perfectly with the frame cross member.

[Racincc85]

Before I get down to technical stuff, I just want to say thanks for all the great information and help. I've learned a ton and feel 100% more confident it taking on this project. MagicRat- I considered the 455 and would love to use it but at the same time i want to keep the car streetable and get somewhat respectable fuel economy. I figured the 403 would be a good engine for a mix of perfromance and economy, if i gear the rear end right and get a torque converter with the right stall speed. With the 455 I'd have to yank the computer/emisson controls, and since it isn't identical externally to the 403 i would have trouble getting the A/C compressor mounted without modifying the lines. I figure that if i get a decent cam, headers, a performer RPM intake, and get a pair of heads with a smaller chambers to up the compression to around 9.5 ~10 :1 (as well as port and polish them) i figure i could get about 400`425 hp. ( what kind of 0-60 time could i get with this?)

I also considered switching tranny's like you said, and from what curtis had to say i would like to stay with the th200-r4 (better gearing than the 700r4 as well as a better lockup converter, plus i don't want to shorten the driveshaft,etc. I also must have an overdrive transmission as this car will be my daily driver when the weather is nice, so a th350 or 400 will not work). The only thing i am concerned about now is whether the stock rear end of the delta will hold up to the extra power.

also magicrat, what were your 0-60 times with the 455 in your fleetwood?

[curtis73]

Most likely your rear is a 7.625" 10-bolt. Its possibly an 8.5" 10-bolt. The 7.625 isn't particularly strong, nor is it particularly weak. At 400 hp, I would seriously consider finding an 8.5 from nearly any HD B-body except wagons. (wagons used a slightly wider axle and you might have fender rubbing on a non-wagon car) You can find them on many Taxis, cop cars, and all Impala SS. If you plan on passenger car tires in like a 235 width, they will lose traction before the rear end blows, but if you plan on 400 hp and getting it to stick to the ground with some performance sticky tires, make sure its an 8.5"

If you want, find a late model B-body with the disc brake rear. Its an 8.5. I can even tell you how to modify your stock proportioning valve to properly operate the rear discs.

Here's a website to help you identify your axle. The site lists a 7.5" which is the same case as the 7.625" If yours looks like a circle, its an 8.5. If its slightly squared off, its the smaller 7.5/7.625" Scroll down to the GM part of the page:

http://truckparts-specialists.com/ca...ture-guide.htm