can you use a 3.0l in a 3.2 car?
 

i have bought an '87 911 with 135000 miles on it. good car but the top end will have to be built. I built an engine off of a 3.0l case and heads and the engine only ha 5k miles on it. I went all out and did everything to this engine to go into a 914-6. I have decided to put the original engine back in it so I am going to be left with this engine.

The case is '78 SC standard sized cylinders with JE pistons 9/1, heads are '78-'79 SC heads, with webcam 120/104. I know everybody usually talks about taking their 3.2 out and putting a 3.6 in but I already have this one and I am hoping to be able to use the 3.0l block I already have with the 3.2 injection.

Will I be able to bolt all of the stuff on the 3.2 right on the 3.0l case and it work correctly?

Ideas?

Jimmy

Seeing as people bolt 3.2 intakes onto their 3.0's for bitz injection yes, but the intake runner size may be different on the large port motor. I'm sure it can work with adaptors if needed.

3.2 injection can be made to fit. You need some longer studs on the intake side of the heads if I recall correctly because the 3.2 manifold wants some plastic isolators (tech term is phenolic spacers) to avoid heat soak into the manifold.

Problem is your 3.0 cams are not agreeable with the 3.2 injection system. The 120/104 has less cam lobe separation (more overlap) and more duration than stock cams or even modified cams designed to improve 3.2 performance. Those changes don't play well with the single throttle body and air flow meter.

So I think if you get a different set of cams you'll be better off. But the ECU programming is also a challenge. The 3.2L chip mapping and fuel delivery is set up to feed a 3.2 displacement. Your lower displacement 3.0 will need some help in terms of chip mapping to get the mix right.

I assume that at some point, you would like to freshen the 3.2 and put it back into the car. To that end, the idea should be to do as little to the car as possible -right?

Maybe putting a set of PMO carbs on the 3.0 is an idea. Use the existing fuel pump, etc, buy the regulator/bypass that Clewett sells, and have at it. Easy and clean.

When you are ready to put the 3.2 back in, you still have a nice 3.0 with PMO's on it. The PMO's sell well even used if you decide to get rid of them. Your total penalty of time and money would be very reasonable to go this route (provided you sell the PMO's when you're done).

angela

The cams I can change..no sweat. I am more concernedabout the mapping
I sure don't want to go to some problem maker engine

I have had carbs for years and love fuel injection so I want to stick with theDME

How are you going to mount the flywheel sensors?
Bruce

Well.. don't know yet. I was hoping someone here had done this and could tell me.
I just have a good motor in stock that I would like to keep whole. If I can't do this I will just build the top end of the 3.2 and be done with it. I have done 914 conversions and am not in any way wanting to do radical changes to the car or motor.Hate to not use a 5K motor but may not be able to unless someone has experience doing this.

Jimmy

sell both the 3.0 and 3.2 to fund a 3.6 conversion?

Subscribing...this will be fun!SmileWavy

Guess my question is...can this be done? Aren't the flywheels different? The 3.0L flywheel doesn't have the TDC pin for the reference/speed sensor, correct? I know the flywheel mating also is slightly different as far as the crankshaft is concerned, but probably can be worked around.

Also, would you need to swap out the DME/ECU for the earlier K-Jetronic box, or is that not needed since the 78/79 3.0L didn't have the O2 sensor. Hmmm?

If you're thinking 'temporary' then IMO Angela has definitely given you a very elegant suggestion, that involves very little changing of engine internals and/or electronics; and a financial outlay that you can recover much easier than the alternatives.

Honestly just do the top end on the 3.2 If you don't mind changing the cams on the 3.0, then you gotta know that doing a top end is simple.

135K on the '87 is nothing. Have a friend who has 170K on his '87, drives it like a madman on the track, and it just keeps on purring like a kitten. Not much indication that the engine has ever been opened up, doesn't use oil excessively. Impressive.

If it were me, I would drop the 3.2, refurb the heads, which is usually not a budget buster, replace the exhaust dilivars with steel, chain rails, etc. Put it back in the car and sell the 3.0. The 3.2 will be good for another 100K and you will have a pocket full of cash. I have PMOs on my 70 and love them, but motronic is sure easy to live with.

Thanks for all the advise.just trying to save some money and use what I already have finished but I will shelve the 3.0 and do the original heads on the 3.2
That being said..Let me redirect the question.
who can do the 3.2 heads without any changes to them. Restoring them to original condition and about how much is that going to cost me?
Again thanks for all this advise!

cgarr will set you up. He's done a number of our heads in our local group of guys.

Thanks Kevin I sent him a message

Are you really going to put that 3.0 back on the shelf???

I have a 74 914 that needs a 3.0. Let me know.

I can sure fix you up NORD.I have all the conversion stuff
engine tyranny coolers oil tank suspension flares valances.....everything.
PM me

I've sent you a PM. Don't need flares, I like slab side, also not a track car,

well maybe alittle SmileWavy