944S head on 951 engine
03-07-2004, 05:12 AM
#91
Race Car
Ahmet and Brian- I'm keeping a short list of interested people and I'll email you directly when I have pistons in hand and more information to share, price, etc.
Matt H.- Yeah Matt, you hear from Garrity layely...?
I've read archives on experimental stuff that's been tried, Wiseco, etc.
Someone actually wanted to build an engine with no coating at all on the pistons just to see if they'd gall...
I'm just simply having pistons made to Porsche spec in low compression ratio for use with the 16V head and figured I'd share as much as I could for now to see whether anyone would be interested.
If I risk my own personal blocks in the R&D stage to secure a viable alternative to being gouged by Mahle for over $300 a piston then where's the harm in that...? These pistons won't be just a low compression replica of the 968 piston BTW. Normally aspirated pistons don't necessarily make for a reliable turbo piston by design of the ring groove area among other features.
Terry S.
Matt H.- Yeah Matt, you hear from Garrity layely...?
I've read archives on experimental stuff that's been tried, Wiseco, etc.
Someone actually wanted to build an engine with no coating at all on the pistons just to see if they'd gall...
I'm just simply having pistons made to Porsche spec in low compression ratio for use with the 16V head and figured I'd share as much as I could for now to see whether anyone would be interested.
If I risk my own personal blocks in the R&D stage to secure a viable alternative to being gouged by Mahle for over $300 a piston then where's the harm in that...? These pistons won't be just a low compression replica of the 968 piston BTW. Normally aspirated pistons don't necessarily make for a reliable turbo piston by design of the ring groove area among other features.
Terry S.
03-07-2004, 02:16 PM
#92
Instructor
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Terry,
the Mahle pistons are not over $300.00 each for the pistons alone - That price includes the wrist pins, and rings. Most piston manufacturers do not "include" pins and rings in their piston price, so make sure you know what you are getting from your supplier.
A "good" set of wrist pins can cost around $400.00 +/-, a set of rings right around $150.00 +/-. Subtract these amounts from the $1290.00 price tag for the Mahle set which includes both and you are actually paying right around $740.00 +/- for the pistons.
Some companies will price their pistons with pins and rings, but that is the exception, not the rule.
Just want to make sure you are getting what you are bargaining for.
Hope this helps.
the Mahle pistons are not over $300.00 each for the pistons alone - That price includes the wrist pins, and rings. Most piston manufacturers do not "include" pins and rings in their piston price, so make sure you know what you are getting from your supplier.
A "good" set of wrist pins can cost around $400.00 +/-, a set of rings right around $150.00 +/-. Subtract these amounts from the $1290.00 price tag for the Mahle set which includes both and you are actually paying right around $740.00 +/- for the pistons.
Some companies will price their pistons with pins and rings, but that is the exception, not the rule.
Just want to make sure you are getting what you are bargaining for.
Hope this helps.
03-07-2004, 05:10 PM
#93
Race Director
Also piston design isn't as simple as you think. I've got a pile of seized, burnt, melted and holed motorcycle pistons for you guys to check out. Pistons actually aren't round or cylindrical because they expand at different rates depending upon the axis. Also the material and design of the pin will make a difference on the dimensions of the piston based upon how heat is carried away... etc, etc, etc...
03-07-2004, 10:52 PM
#94
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Originally posted by 951and944S
The inside diameter of the outlet (at the collector flange) of a 951 manifold is 1-7/8 inches and the 944S and 968 flange inside diameter is 2.0 inches. How is this an "abrupt step down"...?
The inside diameter of the outlet (at the collector flange) of a 951 manifold is 1-7/8 inches and the 944S and 968 flange inside diameter is 2.0 inches. How is this an "abrupt step down"...?
Please keep us posted on your progress with pistons you are working on.
Best regards,
Jeff
03-08-2004, 02:15 AM
#95
Race Car
Scott- thanks for the heads up Scott but dimensionally the final piston should use the stock pin whether or not you buy them with the pistons to keep the least number of unique (read costly) equations from entering into the mix.
I'll be giving you a shout about cylinder head and cam options as soon as I have the piston problems worked out.
Terry S.
I'll be giving you a shout about cylinder head and cam options as soon as I have the piston problems worked out.
Terry S.
03-08-2004, 02:45 AM
#97
Race Car
Danno-
It also ain't rocket science......
Anyways, surely I don't have decades of experience spent on research and developement of personal piston design, logged years of on track miles crewed and raced by the staff of my company nor do I have 30-40 years of forged piston innovation behind me.....
But I know someone who does.......
The final piston design should remain, as stated above in my post to Scott, as close to factory as possible with the exception of increasing the strength of the ring groove area.
Dan, from being in business you know as well as I that if I gave away 4 identical products that require any sort of assembly or are part of a greater single assembly, each individual would arrive at that final goal using their own methods, etc. I'm certain you have your own wacky stories you could tell involving customers. I persoanlly, in building transmissions have customers carry in damaged units from trying to install an automatic with the torque converter still bolted to the flywheel.....! Sure, it's possible to screw up in preparation of a block, choose shoddy machinist, etc. Thing is, I'm putting my blocks/budget on the line in trusting this company as I have in the past and I'm absolutely certain they will come through.
Appreciate the input....
Terry S.
Also piston design isn't as simple as you think.
Anyways, surely I don't have decades of experience spent on research and developement of personal piston design, logged years of on track miles crewed and raced by the staff of my company nor do I have 30-40 years of forged piston innovation behind me.....
But I know someone who does.......
The final piston design should remain, as stated above in my post to Scott, as close to factory as possible with the exception of increasing the strength of the ring groove area.
Dan, from being in business you know as well as I that if I gave away 4 identical products that require any sort of assembly or are part of a greater single assembly, each individual would arrive at that final goal using their own methods, etc. I'm certain you have your own wacky stories you could tell involving customers. I persoanlly, in building transmissions have customers carry in damaged units from trying to install an automatic with the torque converter still bolted to the flywheel.....! Sure, it's possible to screw up in preparation of a block, choose shoddy machinist, etc. Thing is, I'm putting my blocks/budget on the line in trusting this company as I have in the past and I'm absolutely certain they will come through.
Appreciate the input....
Terry S.
03-08-2004, 02:53 AM
#98
Race Car
Jeff Lamb- Thanks for the reassurance. Actually I'm thinking of having my modified 968 manifolds internally ceramic coated in the necessary thickness to address that issue and keep the exhaust gas heat in where it belongs.
You can bet on that.....
and I'd be appreciative if you'd drop in and contribute.....
Terry S.
Please keep us posted on your progress with pistons you are working on.
and I'd be appreciative if you'd drop in and contribute.....
Terry S.
