I just bought a 1992 DX sedan with a blown head gasket. My buddy has a Low Mileage 1994 VX Long-Block laying around with the bottom end disasemmbled. My question is , can I put the Z1 head on the B7 Block. It seems this would give me higher compression as well as V-Tec. Ill use the B7 ECU and just wire the V-tec Solenoid to a RPM switch. Is this a terrible Idea and why? We are pretty experienced mechanics.

 

bump

 

It would give you high compression, maybe too high, also its a VX head so it has VTEC-E designed for saving fuel.

 

your compression would be over 12:1 with that setup. and like BauleyCivic said, that head is designed for economy not performance.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Zer0DazE &raquo;</TD></TR><TR><TD CLASS="quote">your compression would be over 12:1 with that setup</TD></TR></TABLE>

I figured something like that. The VX has those pistons with the massive dish, and the compression is still 9:1...so I knew the combustion chamber had to be tiny as hell. I realized why the VX pistons have such a large dish, its to create the circular swirling effect that it produces in lean-burn mode to reduce gas mileage...that swirling effect would be hard to produce with a piston such as the B7 or Z6.

 

well the b7 head has 200k miles+ on it and the z1 head is under 50k so Im really just looking for a fresher setup. I know the VX has VTEC-E and slightly smaller valves but I figured the higher compression would more than make up for that, also with the B7 computer the super lean VX tuning isnt a issue. So the question is can I run that high compresion without a tune and if so is it wise? and can I just rig up the VTEC like I planned? Thanks for your help.

PS: The compression ends up being like 12.77:1 with the Metalic gasket I was going to use


Modified by RockerX at 6:27 PM 6/22/2004

 

I wouldnt even wire vtec-e if your going to do that. It seems like you want it more for performance purposes than fuel economy.

So heres the deal. Put on the head, Run the B7 ECU, dont wire vtec-e and tell us how it goes. No point in using the RPM switch, because when you engage vtec-e on that motor its to save fuel, not run harder

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Andres-eh2 &raquo;</TD></TR><TR><TD CLASS="quote">I wouldnt even wire vtec-e if your going to do that. It seems like you want it more for performance purposes than fuel economy.

So heres the deal. Put on the head, Run the B7 ECU, dont wire vtec-e and tell us how it goes. No point in using the RPM switch, because when you engage vtec-e on that motor its to save fuel, not run harder</TD></TR></TABLE>

Well the way the VTEC-E works is it runs on one intake valve until the VTEC is engaged , this is in order to promote air swirling at Low RPMs, as opossed to regular VTEC which always uses 2 valves but switches the CAM profile when V-TEC engages, So If I don't wire it up ill only be running on one really small valve all the time, and no Im not doing this for performance (for fear of pissing everyone off) this is going to be my second backup car and Id rather have a newer head on the car so If I decide to sell it I can claim I replaced the head, I usually drive (gasp) a Mustang. On the other hand, increased performance never hurts.

 

if you run a b7 ecu it will be in lean-burn mode all of the time...bad idea

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BauleyCivic &raquo;</TD></TR><TR><TD CLASS="quote">if you run a b7 ecu it will be in lean-burn mode all of the time...bad idea</TD></TR></TABLE>

Huh? Im confused. Wouldnt wiring the V-TEC stop that.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RockerX &raquo;</TD></TR><TR><TD CLASS="quote">
Huh? Im confused. Wouldnt wiring the V-TEC stop that.</TD></TR></TABLE>

No. Non-vtec is the lean burn mode...VTEC E is when the solenoid locks the intake valves together.

12.77 is too high for the street IMO...i'd scrap the idea altogether.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BauleyCivic &raquo;</TD></TR><TR><TD CLASS="quote">

No. Non-vtec is the lean burn mode...VTEC E is when the solenoid locks the intake valves together.

12.77 is too high for the street IMO...i'd scrap the idea altogether.</TD></TR></TABLE>

Right like I said two posts up.

I think your probably right about the compression though . Thats why I asked.
Thanks