Running a JDM motor in IT Honda

[Knestis]

Welcome!

IT rules require that you run US-spec parts only. For example, Canadian VW Golf III's (the make/model I race) were available with manual steering racks. No US model was, so we all run PS. Go download the SCCA GCR (our rule book) and get familiar with the specifics before you spend any $$. You were right to check!

K

[mossaidis]

Welcome SIR!

Questions? Why does the B18B have higher compression? Different pistons? Are the TB/IM setup the same as well? what about port size?

Kirk is correct. USDM only per the rules. Why? 1) Though you are allowed to change pistons in IT, they must be similar configuration, dome, dish, etc. 2) There are undocumented variances between USDM and JDM which make it very hard for tech and others to determine if you are legal at min to the "sprint" of the rules.

My advice if you are truly set on using a JDM engine, take the trouble to make sure you have USDM pistons and your region is "ok" with your setup. Make sure your competitiors are aware of your adjustsments. BUT do not complain when/if someone protests you for having B18B stamped on your block and not B18B1 eventhough you have "made" a "USDM" IT legal-ish motor... cause you have not.

I was in the same boat as you. I could have purchased a D16A SOHC ZC JDM motor which is EXACTLY like a D16Z6 USDM motor and I could prove the were the same... (IM, pistons, head all had the same part numbers). Still, someone could protest me and legally win.

Look it into getting your old B18B1 motor refreshed.

Mickey

[mikelawson]

very nice suggestion Many Thanks

[Chip42]

Look it into getting your old B18B1 motor refreshed.

this. parts availability for the B18B1 is very good, and you can get oversized pistons directly from honda if you need them. If you aren't comfortable doing the work I promise there is someone near you who is.