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Discussion Starter #1
Looking for some tips on building a Z6 for a HC H4 class car. Here is what is allowed:

Balancing/Blueprinting
.040 over max
Piston Rings,any, must fit stock pistons
Valve Guide Material Unrestricted
Compression +.5 over stock
Fasteners unrestricted
Gaskets(hondata spacer)ok
Any crank pulley
Oiling system is unrestricted, no dry sumps tho

Just looking for some tips on building up a reliable, quick, and legal engine. I have to use a USDM engine:TD: so even though I have a JDM ZC VTEC on the shelf I had to get a 170K mile Z6 swap from a EX and I'm preparing to go through it. Thanks in advance for the help.
 

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Looking for some tips on building a Z6 for a HC H4 class car. Here is what is allowed:

Balancing/Blueprinting
.040 over max
Piston Rings,any, must fit stock pistons
Valve Guide Material Unrestricted
Compression +.5 over stock
Fasteners unrestricted
Gaskets(hondata spacer)ok
Any crank pulley
Oiling system is unrestricted, no dry sumps tho

Just looking for some tips on building up a reliable, quick, and legal engine. I have to use a USDM engine:TD: so even though I have a JDM ZC VTEC on the shelf I had to get a 170K mile Z6 swap from a EX and I'm preparing to go through it. Thanks in advance for the help.
I'd definately bore the block .040"/1mm (according to z6 pistons) over. Look into topline pistons for replacements. Boring the motor raises compression, and adding a .014" mill to the head maxes out your limitations. Make sure the pistons you get are the standard compression height, as most manufacturers make their replacements slightly shorter so the compression remains the same, with the overbore.

Porting allowed? If not, do a valve-job for sure, and possibly have it done by one of the best Honda headwork specialists. It's pretty much where most of the gains are made on a ported head.

Don't fall for the "total seal" BS. All it is is a second compression ring that overlaps itself. Most of todays top engine builders are going to a larger gap in the second compression ring, so pressure can be released from between the top and second compression rings. I haven't an idea which ring manufacturer to go with, but honda rings are pretty good. Research this on the forged piston manufacturers wenbsites. Take all the info in, and decide what would be best.

Stock guides are fine, as long as they're sized correctly. Consider replacing them with some bronze guides that have been turned down on the port side, for flow purposes.

ARP headstuds, Hondata(or similar) gasket, stock z6 crankshaft damper, and maybe a moroso pan/pickup with a crank scraper would round out a pretty potent motor.

more ideas later...

-josh-
 

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Is a cam restricted? If not, run a Crower 2. What about fuel and tuneing?
 

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Looking for some tips on building a Z6 for a HC H4 class car. Here is what is allowed:

Balancing/Blueprinting
.040 over max
Piston Rings,any, must fit stock pistons
Valve Guide Material Unrestricted
Compression +.5 over stock
Fasteners unrestricted
Gaskets(hondata spacer)ok
Any crank pulley
Oiling system is unrestricted, no dry sumps tho

Just looking for some tips on building up a reliable, quick, and legal engine. I have to use a USDM engine:TD: so even though I have a JDM ZC VTEC on the shelf I had to get a 170K mile Z6 swap from a EX and I'm preparing to go through it. Thanks in advance for the help.
i dont' know why they wont' let you run turbo.. i'll put on a turbo and boost 6 and call it a day..
 

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Discussion Starter #5
Tuning has to be done with any OEM ecu in place, it can be chipped, piggybacked, whatever, but a stock honda ECU must be in place and operational. About the pistons, they must be OEM or exact equivelents in relation to weight, size, dish/dome, valve reliefs, etc. The compression # and how much I can mill off was what I really needed to know, thanks AMkrew for that. I could just see my engine getting teched and being 1/10 of a compression point too much or something stupid like that. I'm on a budget and work at a fab shop so I'm going to modify a stock pan with an extra cavity and some baffling, along with the scraper if I can find one. The bronze valve guides I had planned on, my dad owns a motorcycle shop and is going to help me install them and do a 3 angle valve job and the allowable portwork. Porting is only allowed one inch into the head and intake mani. Cam unfortunately, must remain stock. Anything to do with the oil pump/system?
 

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the total seal rings are not all second ring. you can get them for the top ring.
 

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Discussion Starter #7
As long as they are the same thickness and don't require any modification to the pistons I can run any rings.
 
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