Eagle rod users come in
 

I just got off the phone with my engine builder and he informed me that he is having trouble getting the wrist pins (weisco) in the rods. They slide in easily/smoothly into the stock rods but with the Eagle rods they slide in half way and then if he wanted to get them in all the way he would half to press them in. He has used belfab and Carillo in the past and never had this issue. Is there something wrong with this set of rods or is this how the Eagle rods are?
__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote

Some rods have to be put in a rod "heater" which heats the rod causing it to expand so that the wrist pin can slide in and out easily. Then once cool the pin is locked in the rod.

Did he heat the ends of the rods prior to insertion of the wrist pins?

edit- CJ beat me.

Even with a full floating piston and rod setup? Seems like they would be extremely tight once it cools down.
__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote

Ed Zachary.

I've done a bunch of reading and found that some people have had to actually hone the small end for the pin to fit smoothly. I read that some have used a brake cylinder hone to do it. Anyone ever heard of this?
__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote

Let me put this bluntly, keep in mind I'm completely serious. If your engine builder did not know that he needed to hone the small end to fit the wrist pin then you need to go pick up everything you dropped off with him for your build and bring it to another COMPETENT machine shop that specializes in engine work. Specifically a shop with import engine experience.

The miata has a floating wrist pin. It is not like the interference fit, of say, a honda rod. You should not have to heat up the small end at all. It should be honed to fit. The rod should have come with a spec sheet for clearances and I would venture a guess at 0.001-0.0015" is what it recommends.

Thanks for your help man.
__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote

Holy shit. Yeah, go pick up all your parts and take them to someone that knows what they're doing.

The rod end needs to be honed to fit the wrist pin.

I'm more than a little concerened about the outcome of this.

Thanks everyone, I'll update ya once I talk to him.
__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote

The eagle rod has a bronze bushing that sometimes needs to be honed. Don't heat the rod...... if you heat the rod your expanding the molecules of the metal there for making it weaker. Also make sure is the rite rod for the app.

lol man u guys are funny ........ im the engine builder.... ive built plenty of engines. i know what im doing its my job.... im sorry we don't use cheap products where u have to modify the brass insert in the rod... the head tech in my shop that use to work for mecha chrome (engine builder for f1 renault) said on a full floating wrist pin set up everything should go threw smooth and tight.. talk to a friend also the works for dinan bmw (bmw daytona prototype engine builder) and said the same... ive build 3 other miata engines including my own and never had this problem. my engine uses carillo and the other belfab and the wrist pins went in smooth. and these engine have been running for 5 to 6 months 20lbs of boost in extreme conditions. we dont use eagle rods on our race engines, but never had this problem with other companies... i just let phil know what was the deal. i know u could bore it out but its going to cost money for my machinist to do it. and i was letting phil know.
i dont know why im replying to this crap. everyone just talks alot of shit and dont even know what the talking about..
if anyone want to dispute with me pm me ill give my # and u tell me other wise

im out
sebastien
ansamotorsports.com

Hahahahahahahaha. We've been down the road before where someone posted about engine work and people suggested he pick up his shit and take it else where, and then YOU came in and said you're the machinist! This is hilarious! Hahahaha.

Its just a problem of fit. Somethings have to be ground to spec if they arn't manufactured under very high standards, or in the case where the sigma is on opposite ends of the spectrum (one ran tight and one ran loose from the manufacturer.) In either case its your job to make the rod go in the hole, man up. :giggle:

im not the machinist and never said i was........ and thats fine i will get the rod bored.... and it would be the machinist job to make it fit.. w/e im done you guys are forum talkers... just tryin to start shit..

No, he's asked for advise. So he's got it. If the guy building his engine is not competent at what's he's doing, then the OP needs to find another engine builder. I assumed that since you're an engine builder, you're also a machinist. How could you not be? It's like part of the process. The machinist will hone the small end as it's probably within one thousandth already. Just because the parts are not on size doesn't mean they're "crap". Some better rods are made to be slightly under size so that they can be machined to exacting tolerances by a knowledgeable engine builder/machinist. Rather be a thousand under size and hone it to exact spec than be half a thousandth out and be fucked. Rod manufacturers can not control the QC in all the different piston manufacturers. So it's common to see parts machined "close" and then left up to the competent engine builder to spec everything out.

I'm pretty sure you should grind or hone, and not bore something like that. Generally when you are maneuvering a few or even a single thou you abrade, not cut. A cutter head of a boring tool will be a bit too violent for that little of material. Plus at that amount of accuracy you almost have to grind, and check until you get it right. Even a drill bit will miss by a thousandth, and that is considering you can get it 100% concentric so the bit doesn’t walk. You really have no idea what you are talking about do you?

splittinghairs.jpg