GZE Pistons in 20V

[aarong420]

Ok, so im trying to find out ways I can lower my compression in my Silvertop 20V to run boost. I was told that the GZE rods and silvertop rods are the same. So I need to know if I can use the GZE pistons on the 20V rods to possibly lower the compression?
Also, is the gudgeon pin the same in the two rods?

[micro214_kp61]

been a while but from what i remember, the AE101 MAP GZE's con-rod is the same as the 2nd Gen 20V ST. some people said they've run the GZE pistons without flycutting the 5th but i personally haven't seen it done. if you're gonna get it flycut, it'll weaken the piston. best bet is to just get the Arias forged pistons from Paradise Racing (if they still have it).

[punter]

Old 8:1 gze pistons clear the valves, the newer 8.9:1 pistons do not.

The pistons fit right in, install the 8.9:1 pistons and it will go sweet.

Who cares if your engine is interference. I've never seen a cambelt break (if changed every 100,000km). And loads of cars are interference from factory.

[Gsolo]

from my experience at work we've noticed that in general toyota will only use a t-belt if the chances of knocking the valves is minimal, otherwise they will go to chain like the 1ZZ. Although i'm sure the blacktop would bend stuff if the belt snapped...

and supposedly the GZE pistons don't need flycut and here stateside i think we only had the 8.0 comp so getting them from the dealer would be fine. I think they have some kind of fancy coating on them too to deal with the heat

[aarong420]

punter I quote.."Old 8:1 gze pistons clear the valves, the newer 8.9:1 pistons do not.
The pistons fit right in, install the 8.9:1 pistons and it will go sweet."

so the only reason i should go with the 8:1 is so they will be non interference? this will be on the safe side....on the performance side thou the 8.9:1 will be better..?

anyway, im not going to cut the pistons, so on the safe side i should go with the 8:1 GZE pistons, and they WILL fit onto the 2nd Gen 20V silvertop rods with nooo problem? meaning the pin will fit with no problem or play>?

And I take it will need to use full aftermarket management to do this? Or will a piggyback system be sufficent?

Also theres a guy selling a VAFC2, maby this will be sufficent enough to run boost?
please let me know about the VAFC2, asap...its selling for about 200US.

[punter]

IMO VAFC2 or similar is a waste of time especially on a 20v, and especially if your changing from n/a to turbo.

so yes, gze pistons do fit in that easy.

But that's not the hard part, the turbo/manifold/exhaust. +intercooler+piping/intake
+ Ecu/tuning +all the little anoying things. are the things that actually cause problems.

[Flashmn]

You can run most boost with 8:1 than 8.9:1 compression

[turbo4ag]

I hope Im not coming off sounding like a know it all.
But a VAFC cannot tune a turbo car properly because of lack of timing control.

Even if you ran 110 octane all day long, and retarded the timing at the dizzy, its still too aggressive. As far as I remember, the max ignition at peak torque on a 20v ECU is 36*. If you retarded the base timing 5* at idle the max advance would be 31*. For any turbo car, even one with extensive chamber work and 110 octance, most tuners will not go over 25* when tuning.


You are much better off using an E-Manage. It will cost around $400, will control fuel, ignition, and VVT. And its popular enough that you can find alot of people who know how to tune them.

Good luck.

[aarong420]

so the emanage would be better than a piggyback?...i suppose it will read the boost?

btw, need to know if silvertop valves will work in a blacktop?

[Flashmn]

E-manage is a piggyback.

Greddy has alot of hype in it. If you want a proper standalone, its Haltech, Hestec, Tatech, KMS, etc even megasquirt is better than a piggyback, because piggybacks have alot of limitations.

most tuners will not go over 25* when tuning.

Even alot of turbocharged cars run more than 25degrees. 20 degrees is pretty much safe.
I'll be running 20 degrees with 95 octane (low octane) pump gas. I sure as hell havent done anything to the chambers and I sure as hell wont bust my engine with knock.