2.7 stroker using 2.5 rods. Need piston info.

[rvaughnp]

I have ran a couple ideas across some members here and i appreciate your replies.

I won't to do the 2.7 conversion but with the 2.5 longer rod. From what i have researched the 2.5 rod on a 2.7 crank spins faster then the 2.7 crank/rod.

I know the other possible alternatives - 2.7 (eta)crank/rod/piston/ i head. or - 2.7 (eta)crank/rod, seta/custom pistons. I have read all there is to read on these two (twice). I can't find the seta pistons and customs with this setup are difficult to get pricing for. Had difficulties trying to get correct specs to order pistons.

Regardless, I like the more tourqe to come from the 2.7 crank and the faster rotation from the 2.5 rods. A few have brought this configuration up, but i have not noticed much detail on the subject from those that have actually gotten this done.

1) I have only seen the reference to .080 shave off and relief recut once.

a) To get a 9:0 CR, what is the shave amount?

b) Is there a certain amount of shave verses CR amount?

c) will any machine shop know how to do this?

d) is there something special in addition to this we should know.

2) Details/specs of custom pistons with CR.

Anymore information would be appreciated.

[rvaughnp]

Ok, i have been continuing to research this and i have ruled out the shaving bit.
please help me !! I have shave my piston ( picture ) This is a good and seemingly logical post for not doing the shave.
I have contacted Ross and will get info from them on a set of customs. I plan on getting info from other piston companies as well.
I will keep this thread updated on this matter, being there haven't been to many with correct info on this particular combo.

Thanks

rvaughnp

[rvaughnp]

Ok, here is where i am at so up to now.

86ETA27 from another site states that he has done the shaving; actually he was the one I was referring to about the statement of “shaving .080” in my previous post. We are emailing back and forth and will try to get any info on the shaving, who what where, how much, when.

Found 2.9 piston at MM. Talked with Teddy, great help, they have the 2.9 or 2900 series piston.
86 mm bore 9:6.1 with the 2.7 crank and 2.5 rods. Was told these are direct bolt, $1170.00 a set (with wrist pins and c clips). Rings $180.00. They use this combo in one of their build motors.

Here is a good and informative post 2.7 Rebuild info - Page 3 - R3VLimited Forums

I will have information from JE, brcperformance and Wiseco in the next couple of days. I have to get a little bit more info and email a data sheet to Ross to get their information.

rvaughnp

[rvaughnp]

I was able to get a 2nd choice... "m 20 fever" from e30tech had some made by bcrperformance. Scott of bcr said he would email the specs on those, as I have the order number from "fever" but I have to get his ok to post that number first. (that number ties to those pistons that he had made.) "fever" has had those pistons in his motor for going on a year and states they have no issues. He had them made to an 8:8.1 cr but Scott said that they could match them to any cr; all for $774.00 including wristpins.

Wiesco was supposed to call me back today but didn't. I expect to hear from them tomorrow. I doubt I will go through sending the info to Ross. We'll see.

Any who, like I said I will post a full report on the manufactures and the specs from said manufactures when this is done.
rvaughnp