LPG Prepped 1UZFE Internals

[Lextreme II]

I just got these pistons for one of our customers. He will be running LPG along with a turbo and aiming for about 600-700 hp. So we took that task and order him some thermo coated forged internals. Pistons look very mean with black coating. We also going to coat the combustion chambers and the valves too.

 

[Treynon]

me like...

 

[SCV8]

That's pretty slick, does the coating take up any needed ring clearance?
What's the C/R?

 

[Lextreme II]

The answer is NO. The CR for this customer is 8.5:1 if i remember correctly. Here are few pictures of the coasted forged piston along with our forged h beam rod. FYI, our rods are direct bolt on to the stock pistons and crank.

 

[cribbj]

If the question is concerning clearance space in the ring lands, I've been advised by the owner of PolyDyn Coatings that the "normal" moly and PTFE coatings are so thin, and take up so little clearance that they can even be used on "tight" new engines with new bearings, without affecting the bearing clearances as they will "scuff" in very quickly. I don't know if the same theory applies for rings, however.

It would be interesting to hear from others on this point, particularly the knowledgeable engine builders.

 

[madhun]

If the question is concerning clearance space in the ring lands, I've been advised by the owner of PolyDyn Coatings that the "normal" moly and PTFE coatings are so thin, and take up so little clearance that they can even be used on "tight" new engines with new bearings, without affecting the bearing clearances as they will "scuff" in very quickly. I don't know if the same theory applies for rings, however.

It would be interesting to hear from others on this point, particularly the knowledgeable engine builders.

G'day folks,

Happened upon this thread when "Googling" 1UZ info; thought i might join whilst I was here. I had a set of Ross forged pistons HPC coated in a 4EFTE, very nice little animals. Wrapped them with a set of Total Seal rings and popped them in. (well at least my engine builder did anyway) When it came time to pull the engine down, (unfortunately due to a wild overboost situation I melted the ring lands on one piston), we were astonished at the condition of the pistons (other than the one with issues). They didn't look terribly dissimilar to the day they went in.

I would definately re-apply the coating on any future rebuilds.

We had also had the exhaust manifold, turbine housing and dump coated; you could actually dampen your finger and touch the manifold at normal operating temperature without requiring a visit to the emergency room. I never really got game enough to try the same on the turbine housing!

 

[MrFluffy]

Lextreme, did you call out the thermo coating because of the numbers the customer wants or because he specified lpg?

 

[Pro]

thanks for the post madhun.

you shoudl also invest in some stainless seats and valves - i can honestly tell you they go a LONG way for engine reliability.