Re-ring Alusils? - Page 18

William Miller · 03-04-2004, 06:10 AM

Thanks Jack! When I checked them I found none loose.

Anyone got any thoughts on the new cylinders and JE pistions?
I got a performance products cataloge last night.
They're selling them too.
They say the cylinders are ceramic coated. I haven't seen any real details or discussions on this. Performance makes it sound like the pistons are coated, but I'm not sure. My intrest is that maybe these 98mm pistons would work in a bored out Alusil?

snowman · 03-04-2004, 07:37 PM

Whats coated, the pistons or the cylinders?

Normally the pistons are coated, with two differen't coatings. One for the top, and one for the skirts. The top coating helps reject heat, the side coatings, usually a molly disulfide coating, reduce skirt drag.

For more info do a search of the internet for ceramic coatings for racing engines.

konish · 03-09-2004, 04:50 PM

For those who have dared...any mileage updates. Rings sealing okay? Don't you freakin'guys know those things can't be re-used!

R/
Dustin

Wayne 962 · Wayne 962's Garage

I re-ringed the 911SC alusil cylinders in my old SC. As far as I know, it's running fine (sold the car about six months ago). Probably got about 3000 miles on the puppy right now. Sometimes they work well, sometimes not...

-Wayne

konish · 03-10-2004, 03:30 AM

Wayne,
I hope I did not offend with my comment above. There were several people that did some pretty amazing analysis on Alusil cylinders, bringing some more quantitative results to the table. My comment was an attempt at sarcasm...probably went over like a fart in church, but I really feel like some of the information concerning Alusils being a crap shoot was probably formed a while ago and has since become quasi-urban legend. I wouldn't dispute any of the info from you or the professionals that you consulted when wiritng your book based as a matter of course, but with all the good analysis and data obtained it just seems to make sense. I hope there aren't any hard feeligs, but from reading this board on a daily basis for the last 6 months, i don't suspect there are any...:-)

R/
Dustin

Nathan M · Nathan M's Garage

Quote:

Originally posted by konish
For those who have dared...any mileage updates. Rings sealing okay? Don't you freakin'guys know those things can't be re-used!

R/
Dustin

Well, I've only done about 150 miles so far, but it's running like a dream. Performance is as good as ever, no smoke (no oil leaks either). Our Goetze technical guys say the phosphated rings will have already bedded in. I put my faith in these guys by re-using the Alusils, so I hope they're right! When I've done more miles I'll post compression results, which I also have from before the rebuild (they were excellent - the rebuild was purely because of worn guides).

Rondinone · 03-10-2004, 05:07 AM

I just broke 300 miles, and from what I can tell the rings have seated. There's just a slight puff of smoke at startup, and none at all during driving. My oil consumption after 300 miles was approx. 1 cup.

Once I get some compression numbers I'll think about writing a tech article, if there's interest.

William Miller · 03-10-2004, 08:30 AM

Mine is a few hundred below 5,000
I will be adjusting valves, leakdowns and compression checks at that time. It's running great especially since I found a euro fuel distributer.
One question is if the new JE pistons that Wayne sells will work with alusils? Performance Products seems to be selling the same P/C combination now. I got the impression that the pistons may be coated to go with the ceramic coated cylinders. I'm not sure I read it correctly, but it's the best oppertunity going at the moment.
Rondinone, If you do the article, I will supply any data I can give you.
I think it will be a great asset 's to the board and the P-car community.
Thanks for all your hard work and if there is anything I can do to help!
(Well, almost anything!)

What happened to the guy that was searching to get oversized coated pistons?

wamcdonald · 05-26-2004, 06:06 AM

What ever happened to this thread???

Nathan M · Nathan M's Garage

Well, I've just covered over 1100 miles. The motor's running real strong, occasional puff of smoke on start up, but oil consumption is excellent. I did the last oil change at 500 miles, and in the last 500 miles of town driving it's not used a drop. I'm planning on a compression test within the next week or so, and I expect the results will be good. Just to recap, my car had covered approx 80000 miles and was rebuilt to do the valve guides. I replaced the rings with new Goetze ones and simply cleaned up the bores with brake cleaner. I'm not saying it'll work for everybody, but in my engine, with the mileage stated above, it seems to have worked for me. If it gets me a few more years of use before having to go for a full rebuild and new P&C's I'll be happy, and there's no reason why it shouldn't.

Porsche_monkey · 05-26-2004, 10:17 AM

I'm just trying to get my engine running well. On occasion it sounds like new, but it is too lean in general so I'm not driving it quite yet.

Rondinone · 05-27-2004, 09:07 AM

Like Nathan, I just broke 1100 miles. I set the mixture Tuesday, and will test it out on the dyno Sat morning. My oil consumption is negligible, but because I've yet to go any real distance between changes I can't give you a reliable number. It starts and runs beautifully now that I've finally worked all the bugs out of the CIS and electrical systems. I did the 1000 mile tuneup two weeks ago and everything looks hunky-dorey inside. I should test the compression one of these days.

My next project is to get this iceac system installed that arrived yesterday. New Seltec compressor, new hoses, two new condensors with auxiliary blower, new evaporator. Can you say real A/C?

James Renfroe · 05-31-2004, 04:33 PM

Rondinone,

I from every Alusil description I read, It is stated that the Alusil pistons are iron plated and that is the combination that works with the Alusil cylinder bores. After examining many KS pistons, I know this to be the case. This is not the case with Mahle Alusil pistons which are not plated, as far as I can tell. If this is correct, how does Mahle run aluminum on aluminum without suffering from the typical accelerated alum on alum wear?

I know for a fact that Mahle produced Alusil cylinders, I have at least a dozen of them at every stage of wear, all of which exhibit 0 reactivity to a strong magnet.

Rondinone · 05-31-2004, 05:02 PM

I would guess that it's because the Nikasil cylinders are nickel plated (silicon carbide particles held in place with nickel metal), so that there is aluminum wearing against nickel.

I'm not nearly as familiar with nikasil as I am with alusil, so the real answer may be more complex.

red-beard · red-beard's Garage

Quote:

Originally posted by Wayne at Pelican Parts
I re-ringed the 911SC alusil cylinders in my old SC. As far as I know, it's running fine (sold the car about six months ago). Probably got about 3000 miles on the puppy right now. Sometimes they work well, sometimes not...

-Wayne

I'm the present owner - The Engine puffs a small cloud on warm up but doesn't smoke after that. Except for the oil leaks, which I think I've finally sorted out (The block the oil pressure sender sits on was loose).

James

KobaltBlau · 07-20-2004, 08:27 AM

James, I thought Wayne was being sarcastic. Can one of you confirm?

red-beard · red-beard's Garage

Confirm what? That the engine was re-ringed Alusil? That is documented in the 101 Projects for your 911 Book.

James

mike95125 · 07-20-2004, 08:46 PM

Correct me if I'm wrong (hey, it happens), but in the begining of this thread Wayne seemed to have the attitude that reringing Alusil was bad Ju-Ju and that it should not be done ala the Porsche gurus. As well he ave me the impression that he would never do it, but he DID. In the Porsche engine book of his he says the usual reccomending new instead of reconditioned. In his 101 projects he re rings. I'm kina confused on this one.

1fastredsc · 07-25-2004, 06:14 PM

I know i haven't posted in this discussion in awhile. But i've got about 150 miles (6 heat cycles) now on my reringed ausil cylinders that i sent out to have the the walls re glazed. Well now when i start it, it gives a very brief huff of smoke and then runs normally. Doesn't burn any oil, just a quick blow on cold start up. Anyhow, runs great, couldn't ask for more. When i start racking up some serious mileage, i'll check back in and post the average oil consumption.

Doug Steinel · Doug Steinel's Garage

1fastredsc, what is "re-glazing" the cylinders mean? Sounds like something you do to a doughnut.