JJayB

Janiana993
Some good advice on pistons. You might consider upgrading your oil pump to the RSR or if $ are not a concern 962 oil pump. Very slight case grinding required.

IrocMan

Hi,

-just my humble opinion-

I saw broken segments on N.A. club and race engines (3.6 and 3.8) using JE pistons.
The guys from JE claimed it was because we hit too much in cold engine (what I can't believe on at least one of them). From this time I decided to deal with Mahle, which design is sometime less efficient, but I never saw a burned Mahle piston on a correctly set engine.
On turbos, I was working with a specialist in north of France who claimed to use OEM pistons only, working more on the engine management (twin injection, and big work setting the spark advance).

cheers

IrocMan

I agree with other points of view (sorry for posting before I read).
To make a reliable club/street engine I would also work on exhaust valves guides and seats (at least).

What's the main difference coming with a 962 pump ? I don't know this one. (Compared to a Motorsport for GT2 for instance ?).

Kevin

Difference between the pumps about 9K

Steve Weiner-Rennsport Systems

Yessir, and with excellent results for many many years.

For the record, my use of the Total Seal gapless rings (2nd groove only) is selective and we still use a of Goetz rings in race motors where there isn't time to seat the TS ones.

Janina993

Steve, can I steel your knowledge a bit more?

Are you using these dimensions with TS in turbo motor? 1,75 x 1,75 x 3,0

What oil are you using during engine break-in with TS?

Steve Weiner-Rennsport Systems

Yessir, I am in most situations. Some race engines get thinner rings,.....

I do all running-in and ring seating on our SuperFlow engine dyno using synthetic oils; usually a 10-40 since I can totally control oil and cylinder head temperatures.

Once the rings have seated, as indicated by leakdown figures, and the engine is back into the car, I switch to the regular oil I will use; Mobil 1, Redline, or one's choice,...

Janina993

Thank you Steve! This all is golden information.
You have nice equipments. I have to do it on streets...

IrocMan

What about the specs ?

I have had a 959 pump and can tell that I was a bit disappointed since it wasn't so better than my original 964 turbo one... So I use to give relativity to these 956/961/962 engine parts comparing to what we can get from a TT or GT2/3.

Kevin

The 935 and 962 pumps have 3 oil pickups to scavenge the oil. For the money you can't beat the new GT3-GT2-X50 oil pump.

Red9

How do they compare to the R pump?

Janina993

Steve, how you recommend to make first start and drive-in cyckle on streets with gapless rings?

Steve Weiner-Rennsport Systems

First,..if you have new cams in your motor, those need to be considered in the initial startup & break-in procedures.

Generally speaking, I will start the engine and immediately run it at 2000 RPM for 15-20 minutes for cam & rocker break-in. Then I follow the normal ring seating driving cycles (in the car) of constantly varying my speeds and doing full throttle blasts between 2000 & 4500 RPM (for the first 2000 miles), backing off each time to cool and lubricate everything on the closed throttle.

This helps the rings to seat and you'll need to monitor leakdown figures to know when this is completed. Leakdowns around 1-3% tell you that the rings have seated. Allow several thousand miles for the TS gapless ones to complete the process.

Kevin

The problem with gapless TS rings is that if you do not get them to seat the rings will glaze the cylinders.. When that happens you will NEVER be able to reseat the rings and you have to tear down the engine. Combustion gases leak past the ring set, blowbye and blowbye allows carbon to build between the ring lands. This prevents the rings from seating and working thru the up and down motion. It is tough to reseat these rings on a turbo engine without the aid of a dyno! What's even worse is now you have combustion pressure in your engine case, causing oil to be pushed thru your turbochargers and then your engine ingests this oil and burns it causing more carbon to build up.

I can't stress hard enough that you will wish that you took this advice and just purchase a set of Original Mahle pistons and liners for your engine build.. It can get expensive the second time around.

Steve Weiner-Rennsport Systems

Kevin is right in that Mahles P/C's would have really been the best choice for your build and that its not too late,...

I've never had any troubles with TS gapless ring seating over the past 28 years, but I've always had my engine dyno to do that. It merely requires a more disciplined effort when you do this in the car.