Holiday ride of shame

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Vic Skirmants
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Re: Holiday ride of shame

#136 Post by Vic Skirmants » Fri Dec 27, 2019 8:57 am

Dan; all 86mm cylinders will be "thin". To make a thicker wall, you would have to machine the heads. This is what people do when using the much larger 90mm and above cylinders.

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Ashley James
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Re: Holiday ride of shame

#137 Post by Ashley James » Fri Dec 27, 2019 9:33 am

I’m glad you have the cause of the leaking oil, but not I suspect the cause of pinking, which would account for the seizure/piston damage. If the timing is correct, the car shouldn’t pink unless compression ratio is too high.

I think you should measure the compression ratio and lower it to around 9.2 to 1 if it’s higher. You don’t need pinking ever and my car doesn’t do it with AA pistons and jugs.

It would also be wise to put it on a rolling road to establish that the fuel air ratio is correct at all speeds because this is crucial. What the heads looked like on dismantling is irrelevant.

In my opinion the camshaft doesn’t differ enough to be an issue. If you set valve timing with a degree plate you’ll probably find it difficult to get within 11 degrees of the quoted spec anyway. I haven’t tried with a 356 engine but I have with many others.

I can’t see anything in this discussion that places the blame on AA, the impression I get is that it’s a timing or compression ratio issue as well as a jug crack.

Obviously mine is just an opinion amongst many and should be treated as such.

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Re: Holiday ride of shame

#138 Post by Dan Epperly » Fri Dec 27, 2019 1:03 pm

Martin Benade wrote:
Fri Dec 27, 2019 1:12 am
Without rereading the whole thread to be sure this wasn’t answered, the chambers are of a reasonable volume?
I will have to measure when I get them back.
Right now I'm just glad to find out it wasn't anything I did that caused the engine to fail. That it was the garbage cylinders.

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Re: Holiday ride of shame

#139 Post by Mike Horton » Fri Feb 07, 2020 11:55 pm

Dan, do you know what the actual compression ratio Was?
... that is Not a nice to know piece of information, but critical for engine life. On the available fuels today, there is no way I'd run the stock SC, or 912 C/R... you are too smart not to know.
Mike

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Re: Holiday ride of shame

#140 Post by Dan Epperly » Sat Feb 08, 2020 11:40 am

Hi Mike, I've not touched the pile of parts because I'm finishing up bodywork and paint on my 60 VW double cab project.
I was rereading an old thread and remembered that the piston and cylinder kit that came with the engine was an industrial 85mm set with flat top Pistons that were beveled, exhaust pocket deepened and cut down cylinders to increase compression with one copper spacer.
Several guys advised against using this set so I went with the AAs.
After having had one of my AA cylinders crack I'm hesitant about buying a new set of AAs.
So now I get to ponder what Pistons and cylinders to use, theshortened Mahle industrials or something else...

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Al Zim
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Re: Holiday ride of shame

#141 Post by Al Zim » Sat Feb 08, 2020 3:29 pm

I spent a little more time than I should have looking over the 10 pages of comments regarding you engine situation. Nowhere was there any mention of brass shavings or particles that were present in the disassembly of the engine! What did you decided on that? al zim
 

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Re: Holiday ride of shame

#142 Post by Mike Horton » Sat Feb 08, 2020 6:11 pm

Dan Epperly wrote:
Sat Feb 08, 2020 11:40 am
Hi Mike, I've not touched the pile of parts because I'm finishing up bodywork and paint on my 60 VW double cab project.
I was rereading an old thread and remembered that the piston and cylinder kit that came with the engine was an industrial 85mm set with flat top Pistons that were beveled, exhaust pocket deepened and cut down cylinders to increase compression with one copper spacer.
Several guys advised against using this set so I went with the AAs.
After having had one of my AA cylinders crack I'm hesitant about buying a new set of AAs.
So now I get to ponder what Pistons and cylinders to use, theshortened Mahle industrials or something else...
Dan, you are erroneously laying blame on the AA P/C set. The problem, is in the heads, and too high a compression ratio. Go to my profile, and contact me by the e-mail link. I'll get back to you, with my phone #, many highly experienced folks here, are trying hard to help you. Like others had offered, if you'll call me back, I think in a short visit, we can get you along the way to happiness, in one of your two options.

Mike Horton
Mike

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Jacques Lefriant
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Re: Holiday ride of shame

#143 Post by Jacques Lefriant » Sat Feb 08, 2020 7:58 pm

Hi Dan
if I remember correctly you can not use the 85mm ind. pistons with a counterbalanced crank and the pistons being cast tend to crack thru one of the holes in the oil control ring to the piston pin bore if you use more than 4000 RPM.
j
 

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Re: Holiday ride of shame

#144 Post by Mike Horton » Sun Feb 09, 2020 1:27 pm

Jacques, are you referring to the factory flat topped industrial sets?
Mike

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Re: Holiday ride of shame

#145 Post by Jacques Lefriant » Tue Feb 11, 2020 6:56 pm

yes
 

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Re: Holiday ride of shame

#146 Post by Dan Epperly » Tue Feb 11, 2020 7:40 pm

So the industrials are out of the picture.
Anyone need a paper weight?

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Re: Holiday ride of shame

#147 Post by Mike Horton » Wed Feb 12, 2020 12:16 am

Dan, cool your jets;

It is obvious to me, that those heads, and the modified Industrial piston set, were machined to be a matched set. When you get the measured combustion chamber volume, we'll know for sure. Either those heads had been cut way too much, or, the industrial piston set was available, and since it was a "big Normal" (about 7.5:1 in the original N size) to get the C/R up, for more power, then, the heads were cut, to yield that C/R. You inadvertently stepped into this quagmire, innocently, by not knowing the head volume, and installed a relatively high C/R, about 9.2:1 P/C set, with the very small chamber volume set of N heads, yielding the "way too high a C/R" combination, which lead you to this end result.

Don't ditch them yet, they are likely married to those Ind. P/C, for life. Some more measurements, will sure help out here in this quest, for the answer, like it or not,
Mike

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Re: Holiday ride of shame

#148 Post by Dan Epperly » Wed Feb 12, 2020 3:21 pm

Mike Horton wrote:
Wed Feb 12, 2020 12:16 am
Dan, cool your jets;

It is obvious to me, that those heads, and the modified Industrial piston set, were machined to be a matched set. When you get the measured combustion chamber volume, we'll know for sure. Either those heads had been cut way too much, or, the industrial piston set was available, and since it was a "big Normal" (about 7.5:1 in the original N size) to get the C/R up, for more power, then, the heads were cut, to yield that C/R. You inadvertently stepped into this quagmire, innocently, by not knowing the head volume, and installed a relatively high C/R, about 9.2:1 P/C set, with the very small chamber volume set of N heads, yielding the "way too high a C/R" combination, which lead you to this end result.

Don't ditch them yet, they are likely married to those Ind. P/C, for life. Some more measurements, will sure help out here in this quest, for the answer, like it or not,
For sure they were married. I will measure the head chambers before I do anything, but if Jacque is right it sounds like using those Pistons will yield very bad results if I push them and I push my cars.
Plus I was told my cylinders were likely cut down to up the compression.
So I will do any measuring before I jump the gun.

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Re: Holiday ride of shame

#149 Post by Mike Horton » Wed Feb 12, 2020 5:09 pm

Dan, does that engine still have the non-counterweighted crank?
In your stash, do you have uncut 22*, or 30* chamber angle heads?

You can, through the cylinder hole, remove the offending cylinder connecting rod, to inspect the bearing surface condition. Then, if teh bearing is clean, re-install it, at the cost to you, of only 2 new rod nuts, and the investment, of your time. The rod bearings, are the last stop in the oil flow journey, and that oil, will have already traveled through the main bearings, so that inspection, will tell you a lot.

You've got us all "hooked" on this mystery now, and we are watching this thread, like the next episode of a TV series...,
Mike

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Re: Holiday ride of shame

#150 Post by Steve Turino » Thu Feb 13, 2020 4:33 pm

This is an amazingly fascinating and informative thread for someone just embarking on an engine rebuild. Very sorry for your troubles Dan, but thank you none the less.
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