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Hey everyone,

Has anybody tried using the pistons and rods from the GX Civic in a D17A2 block? I assume they run the same crank. We don't have a GX in Canada so it's tough to find information.
Apparently the GX was a D17A7 and ran on natural gas. However,
what caught my interest is that it has a 12.5:1 compression ratio compared with 9.9:1 on the D17A2 and 9.5:1 on the D17A1.
This might be a great way for us N/A guys to up our compression and stick to using Genuine Honda parts. Also, looking at the prices from Majestic Honda, these parts would be cheaper than buying Crower rods and Wiseco pistons.
Anybody with information please share.

Thanks a lot,

Warren

 
Rep Power: 331

boilermaker knows something about this, he was telling me about it not long ago.

 
Rep Power: 424

There have been several attempts to run setups like this for honda challenge race motors. The dynamics of combustion for CNG are somewhat different and using those slugs with gasoline engine cylinder heads seems to yield a compression ratio of more than 13:1. To make any sort of NA power you need to rev the living hell out of it, and even still... I think they were getting around 160-170 whp out of the engine. The problem is when you rev a toothpick rod to 9000 rpms, it lasts 10-20 minutes as everyone has discovered.
I wouldnt try it. The best chance you've got if you wanted to go crazy would probably be to get a D15B piston from a JDM VTi, (its ~.4mm taller and has a smaller dish than a D17 slug) but you'd have to machine the skirt down so that it clears the bottom of the sleeve. I never did the compression calculation, but I'm sure it would be a bit more reasonable, and the motor may last a little longer. The rods just arent gonna be able to take the pounding. I think if you had the crank machined for D16 rods (they're the same length but are .150" wider) you might have a fighting chance. But by the time you did all this crap, you'll have spent enough money to just buy the aftermarket parts.