BrianRMV

I'm beginning to think that I'm not that far away from committing to having a rebuilt engine installed in my 1986 951. My mechanic did a compression test earlier and the results were something like 125 50 125 125. I did not memorize the numbers, but those are close. This is not a project I'm going to get into very soon, but I need to start doing some research. Any suggestions on who rebuilds or sells rebuilt engines? I would have the work done by my local mechanic.

NelaK

I saw a complete supercharged 944 engine for sale. Not quite the same thing but maybe a decent alternative?

https://www.porsche944usedparts.com/...s/show/7999921

951and944S

If you aren't a PCA member already, go to the national site at www.pca.org , find your region, then your local chapter.
Look for email contacts of some of the officers, president, treasurer, DE/race director, etc.
Give one of them a shout and see who the local chapter members and racers use.

Being local is gonna save you a bundle in shipping, risk of damage, etc. plus if you encounter any problems, it's always best to not be dealing long distance.

If it turns out that you'd have to send farther than 1-200 miles anyway, you might consider, Chris White (NY State) at 944 Enhancement, Lindsey Racing in Oklahoma.

If you can/have time to be the "contractor" for the job, have your local disassemble the engine, distribute the engine subassemblies yourself (cylinder head, block, etc) to local/semi local machine shops (again, check PCA members) then have your local guy just do the assembly and re-install.

T

BrianRMV

Thanks for the suggestions. I have dealt with LR and really like them.

One thing I'm really curious about is the low compression read on the one cylinder. At that low of a number should it be really noticeable when driving? The car seems to pull well. This is the only 951 I've ever driven, so I don't have a good reference point. Would it be worth a trip to the local dyno?

wildcat077

Actually , you would need to do a leakdown test on your engine ... it will pinpoint the issue on that cylinder , maybe all you have is cracked/broken rings and if you're
lucky enough your cylinder bore is intact !

That's a whole lot cheaper to fix than replacing the engine !

BrianRMV

Thanks for the idea. That definitely sounds like a good approach. I've wasted way too much money throwing parts at stuff in the past. I'm not prepared to take that approach with an engine. It's interesting to me that I had a leak-down test done a few years ago by a different mechanic and he said all cylinders were in spec for a new engine. He did not give me the numbers, but he did a lot of work on 951's, so I have no reason to doubt his results.

harveyf

I agree with the above comments. Understand you're probably not going to do this on your own but there is no such thing as too much information. Here is a link to a 4 part series I did on rebuilding a NA engine. I'll probably get some feedback but there are no substantial differences in the rebuilding process between NA and turbo. There are definitely differences in the internal parts, such as valves and the ceramic lining inside the exhaust valve ports of the head. Actually, the head and block featured in the articles are from a turbo. The block was scored and so I had steel sleeves installed. Hopefully you will not need that but not the end of the world if you do.

As noted above, the leakdown check is your next step. That will point you to rings, valves, or head gasket regarding the low compression. Google it. It's pretty straightforward. Non-invasive. All you need to do is remove your spark plugs and be able to rotate the engine to the compression stroke on each cylinder. The gauge is cheap enough but it needs a source of compressed air.

https://newhillgarage.com/2018/04/27...ebuild-part-1/

PS My son lives in Seattle. He doesn't know squat about Porsches. But if you want some high end software written he's your guy.

951and944S

While I do agree, if I were working on a few years old car with 50k miles, next would be leak down.

But this is a 33 year old engine.

SO, you pull the head...., nope, no chunk missing out of exhaust valve, no valves appear to be sticking, head gasket looks bad but may not be problem.

So, you proceed.

Suspend engine, remove crossover, oil pan, push piston out, yep, there it is broken ring.

So now you have almost a bare block sitting in the engine bay that you wished you would have yanked from the get go.

Talk about bad money....?

What's the mileage on this car...?

T

BrianRMV

Thanks for the input.

The car has 201k. I had a new head gasket installed about 3 years ago, along with timing belt, water pump, etc.