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fredraud 04-05-2011 12:30 AM

2 Attachment(s)
Well I finally got my pistons. My design, ceramic coated tops, coated skirts, 4032 forged alloy. Light and beefy.
Hopefully in a month I can prove that the hta68 does not need e85 to wake up. At 8.73:1 on 93, 27lbs boost tmic we shall see what the obxt puts down. :). I think they are sexy, and I got the only 2 sets on the planet!


BAC5.2 04-05-2011 12:37 AM

Are those just custom CR Wiseco's, or did you design them entirely and have them made?

What bore?

fredraud 04-05-2011 12:42 AM

Not cp,nor wiesco. Neither would do a 4032, as they did not have raw forgings. Yes my design or , myself and twe. From our solidworks solid model.

fredraud 04-05-2011 12:44 AM

Bore is a drop in.. 99.538 is what they measure, so an A bore with some honing, to give .0015 ptw clearance.

BAC5.2 04-05-2011 09:18 AM

That's excellent. Good work! Who ended up making them? Was it a piston manufacturer, or an independent machine shop?

rao 04-05-2011 09:24 AM

Very nice.

Nice picture as well :)

sumfoo1 04-05-2011 10:32 AM

they look good i'd, like to do something with a similar shape but with a more drastic contour as to not require valve reliefs (hot spots).

rapture 04-05-2011 10:36 AM

subscribed. can't wait to see the #'s from this i'm looking into very similar set up with mine just torn between bnr hta or bw efr. prob goin bnr route tho. is that the turbo you got ?

fredraud 04-05-2011 11:18 AM

The picture is kinda deceiving, as there really is no sharp edges. Reliefs have a 1mm radius. Plus they are ceramic coated.
As I stated in the built motor thread, I am trying to maximize quench Area without sacrificing combustion turbulence/ swirl.
I've worked with just about every 3d modeling program on the planet.
Used sw 2011 with fea and flow analysis. Spent about 80hours on them. Used a Cmm machine to map out the combustion chambers on the b25 heads ect ect. I may be just a bit to anal.

I got diamond to manufacture the pistons, they have always been great in my experience. They worked with me on laying out ring size/ land layout.

I'm running a Bnr hta68 on 93.

Hopefully will be able to get it on sonny's (aka airboy) dyno next month
My target is 375-400 streetable awhp


sumfoo1 04-05-2011 01:31 PM

Cool i mean you piston design looks to be the best i've seen...

how much for a set ?? LOL

BAC5.2 04-05-2011 01:38 PM

I agree with you on Solidworks. I've got thousands of hours with Solidworks and a few other CAD software. For overall user interface and speed, SW is one of my favorites. I do all of my at-home and freelance design work using SW.

I'm curious about your FEA and flow approach. Did you model the head, or just put the piston in a cylinder and have a cap with similar geometry to the head with an inlet and outlet where the valves are?

I've had a few ideas about engine assembly FEA, but haven't had any time to actually try anything out.

fishbone 04-05-2011 01:42 PM


Originally Posted by fredraud (Post 3335497)
I think they are sexy

You know what else I think is sexy? That picture of Holmes on Homes, in a sleeveless shirt and overalls.
'the hell is that doing there, man?

fredraud 04-05-2011 06:10 PM


Originally Posted by fishbone (Post 3336205)
You know what else I think is sexy? That picture of Holmes on Homes, in a sleeveless shirt and overalls.
'the hell is that doing there, man?

Met him a few times before he had his shows. Ran into him in Calgary, wife got me the autographed picture a few years back.
I like what he stands for,doing it right the first time. Come to think of it pretty much everything I get involved with I do the same way Holmes does... Tear it all apart, start from scratch using only the best parts. Lol

No I'm not into mr clean porn

I should post up some picks of what I'm doing with the 5mt and the r160...

Life is great when you have acess to Cnc machinery, and know how to use it.

NSFW 04-05-2011 09:16 PM

What turbo will you be using?

Also, what happens to the compression ratio if you remove the raised area in the center? I'm pondering a built motor next summer, but I want to keep the CR that I have now (8.3 IIRC).

bnguyenbb6 04-05-2011 09:26 PM

Just curious, why were you so adamant about 4032 vs 2618(CP, most)?

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