Performance Engine Mods / Replacement for 87 Supreme Coupe?
#1
Performance Engine Mods / Replacement for 87 Supreme Coupe?
Hi --
I am the proud owner of an 87 Supreme Coupe that has a little rust, but it's worth saving! I like the car, but I would like a little more power than the factory 307. Have been told by a friend that some popular options for Olds power are the 330, the 350, the 425, and the 455. I have heard of Oldsmobile having built a 260 briefly, but am not sure it can do much better than my 307.
I am not interested in a big-block, as I think it might be too much power for the car. I am thinking a 330 would do nicely -- I have seen factory power ratings of 310-325 hp, which is enough for me. My questions concern compatibility with the car's factory configuration, as I would like the car to look pretty much stock after the conversion. I, however, am not particularly mechanically inclined and am seeking some advice.
First, are engine mounts and brackets for all small-block Oldsmobiles the same? If not, what differences are there?
Secondly, what parts, if any, can interchange between the small block Olds engines?
Third, can the 307's factory emissions controls and ECM be used to carburete a 330? My friend is thinking if bigger jets can be installed in the factory E4ME carb, the computer and oxygen sensors should see no difference.
One other question -- I have heard one conversion with small-block Chevrolets is to destroke a 305 block with a 327 bottom end. Is it possible to destroke a 307 block with these parts from a 330? If so, any ideas on performance increase over a standard 330?
My friend (more of a Buick expert than Olds) had thought of using a 4.0 Aurora V8 just for the sake of being different. Is this actually a real Oldsmobile engine, and if so, I know it is FWD, can it be used in a RWD application?
Thanks in advance for any advice given......
I am the proud owner of an 87 Supreme Coupe that has a little rust, but it's worth saving! I like the car, but I would like a little more power than the factory 307. Have been told by a friend that some popular options for Olds power are the 330, the 350, the 425, and the 455. I have heard of Oldsmobile having built a 260 briefly, but am not sure it can do much better than my 307.
I am not interested in a big-block, as I think it might be too much power for the car. I am thinking a 330 would do nicely -- I have seen factory power ratings of 310-325 hp, which is enough for me. My questions concern compatibility with the car's factory configuration, as I would like the car to look pretty much stock after the conversion. I, however, am not particularly mechanically inclined and am seeking some advice.
First, are engine mounts and brackets for all small-block Oldsmobiles the same? If not, what differences are there?
Secondly, what parts, if any, can interchange between the small block Olds engines?
Third, can the 307's factory emissions controls and ECM be used to carburete a 330? My friend is thinking if bigger jets can be installed in the factory E4ME carb, the computer and oxygen sensors should see no difference.
One other question -- I have heard one conversion with small-block Chevrolets is to destroke a 305 block with a 327 bottom end. Is it possible to destroke a 307 block with these parts from a 330? If so, any ideas on performance increase over a standard 330?
My friend (more of a Buick expert than Olds) had thought of using a 4.0 Aurora V8 just for the sake of being different. Is this actually a real Oldsmobile engine, and if so, I know it is FWD, can it be used in a RWD application?
Thanks in advance for any advice given......
#2
All small block Oldsmobile engines will be a direct swap into your car. I think the problem with a 330 is that they are harder to find than a 350 or 403. A 350 will be easier to find and probably cheaper.
All small blocks are exactly the same on the outside so everything will swap over. Use the same motor mounts for a 307.
A lot of things will interchange on all Olds engines. I think some of the different things are the accessory brackets between small blocks and big blocks, intake manifolds between big and small blocks, I think that is about it.
I have heard of people using the computer system with 350's, but I am pretty sure they need to be fairly stock with low compression to work. I am not sure what people do with the A.I.R. systems when they swap engines, they usually dont have the holes drilled in the heads for the air tubes.
I have no idea if destroking a 307 is possible or even worth it, probably not.
The 4.0 V8 was only used in Oldsmobile cars, but I am pretty sure it was just Oldsmobiles version of Cadillacs North Star engine.
I think I got most of this information correct, please dont hesitate to correct any of my info if I am wrong.
All small blocks are exactly the same on the outside so everything will swap over. Use the same motor mounts for a 307.
A lot of things will interchange on all Olds engines. I think some of the different things are the accessory brackets between small blocks and big blocks, intake manifolds between big and small blocks, I think that is about it.
I have heard of people using the computer system with 350's, but I am pretty sure they need to be fairly stock with low compression to work. I am not sure what people do with the A.I.R. systems when they swap engines, they usually dont have the holes drilled in the heads for the air tubes.
I have no idea if destroking a 307 is possible or even worth it, probably not.
The 4.0 V8 was only used in Oldsmobile cars, but I am pretty sure it was just Oldsmobiles version of Cadillacs North Star engine.
I think I got most of this information correct, please dont hesitate to correct any of my info if I am wrong.
#3
I have heard of people using the computer system with 350's, but I am pretty sure they need to be fairly stock with low compression to work. I am not sure what people do with the A.I.R. systems when they swap engines, they usually dont have the holes drilled in the heads for the air tubes.
Also, my friend has me under the impression that the AIR system actually plumbs into the exhaust manifolds..... Does anyone make headers that allow this?
You probably are right, but neither I nor my friend have ever seen one to know for sure.
#4
Welcome to our site. The 330 was produced in the fifties and is not the same as your eighties 307. I would recommend that you look for a 350, they can produce nice horsepower for a street car and you can find performance parts easier too. Forget about the 260 it is way too anemic. There are some threads discussing the 307 and what can and cannot be done to it, a simple search should reveal at least two threads on it.
#5
This link should give you all the options:
http://tlentz.oldsgmail.com/more_power.html
Unfortunately, it is much more cost effective to drop in a 350, which I have heard can be made to run with the CCC system (with a few tweaks of course...)
http://tlentz.oldsgmail.com/more_power.html
Unfortunately, it is much more cost effective to drop in a 350, which I have heard can be made to run with the CCC system (with a few tweaks of course...)
#6
Factory numbers can be (and usually are) misleading.
Yes
Yes. Commonly used with 350s.
All "small block" Olds used the same 3.385" stroke. Differences in in displacement are due to bore diameters.
Yes and Yes. They work very well in "light" cars.
You have the 330 ('64-up) confused with the 303 ('49-'53)
Norm
Norm
#7
If not, what differences are there?
Secondly, what parts, if any, can interchange between the small block Olds engines?
Also, my friend has me under the impression that the AIR system actually plumbs into the exhaust manifolds..... Does anyone make headers that allow this?
One other question -- I have heard one conversion with small-block Chevrolets is to destroke a 305 block with a 327 bottom end. Is it possible to destroke a 307 block with these parts from a 330? If so, any ideas on performance increase over a standard 330?
My friend (more of a Buick expert than Olds) had thought of using a 4.0 Aurora V8 just for the sake of being different. Is this actually a real Oldsmobile engine, and if so, I know it is FWD, can it be used in a RWD application?
#9
#10
The Aurora 4.0 liter motor is a version of the Northstar. Cadillac Hot Rod Fabricators (http://www.chrfab.com/) sells parts to swap them into RWD applications. The biggest problem is the water pump, which is driven off the back (driver's side) of the front cam. When you put the motor in a longitudinal orientation, the pump wants to occupy the same space as the brake booster in most cars. The usual solution is an electric pump, but I remain skeptical of those for long term street use.
What about using Hydraboost instead of the vacuum brake booster. There is also a bellhousing out there to mate something like a Muncie 4 spd to a FWD engine. I have one.
#11
Okay, now I'm confused. I was of the understanding that Olds engines all shared the same stroke, and that bore was the difference in displacement. Have also read that some race 307s are actually sleeved 350s. Now I'm being told that a 307 cannot be bored to 350. What gives? Are the blocks that different?
#12
The 307's along with all the late 70's blocks are windowed light weight castings. Building one to the horse power level you are looking at would be ok but the block starts to flex with higher horse power engines so to make more power you have to use light weight parts. I think some of the 307's that are sleeved 350's use the older blocks so the block is more stable.
#13
The Aurora/Northstar uses a modified version of the metric bolt pattern. One bolt has been moved and the starter is located in the valley between the cylinder heads. CHRF sells modified S-10 automatics and manual trans bellhousings to use the Northstar motors for RWD applications. They also sell the correct M/T flywheels.
By the way, in addition to the Aurora/Northstar motors, the S-10 transmissions allow you to bolt a supercharged Buick 3800 or DOHC 3.4 liter motor into a RWD application. There's at least one G-body Cutlass with the 3800 SC drivetrain on the web. I also saw a very cool swap of the DOHC 3.4 into a Vega.
#14
Have also read that some race 307s are actually sleeved 350s.
Now I'm being told that a 307 cannot be bored to 350. What gives? Are the blocks that different?
#15
Before you drop in a new engine,
What is the gearing in your rear axle???
Most of these cars came with a 2.41 or so axle gear (my 78 had a 2.29!),
a change to a 3.23 - 3.73 will make the 307 feel like a new car.
REALLY.
You will think you found 50 hp.
This should be the first thing considered, in my opinion.
If you have already addressed this issue, great.
Jim
What is the gearing in your rear axle???
Most of these cars came with a 2.41 or so axle gear (my 78 had a 2.29!),
a change to a 3.23 - 3.73 will make the 307 feel like a new car.
REALLY.
You will think you found 50 hp.
This should be the first thing considered, in my opinion.
If you have already addressed this issue, great.
Jim
Last edited by Warhead; December 28th, 2008 at 02:09 PM.
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