Was up honda tech

I have a jdm type r engine which i recently bend the exhuast valves due to the cam gear bolts giving up and slipped, so i took off the head took it to get resurface, clean and replaced valves with supertech flat valves, installed the head cams tdc aswell as the crank timing belt nice and snug fire it up starts up good but when i took for a test drive and wen i go wide open throttle it hesistates to go u hear more of the cai but the car doesnt move like it use too, is timing off ? Or do i need to retune since there diff. Valves ? Any help thanks

 

Flat valves can increase comp by .03 depending on what else is done. In theory yes you should tune the motor. First go through the basics. Take the vc off and confirm mechanical Timing is correct and bring the engine to TDC by hand and check your cam gear marks. If that checks out check the timing with a timing gun, get that correct then determain if your having a fuel/ tune issue. A AFR gauge is a must these days! there dirt cheap and easy to instal and lets you know whats going on with the fuel trims. If you had one you could of refrenced the hesitaion with the AFR you get at that time, sounds like its going lean! which means you need to dyno tune the engine, It does have flat valve that increase comp so your stock ecu is not going to be able to cominsate enough fuel for the air.

 

Also make sure you set the valve lash correct! many people think they set the valve lash correct but do it very poorly and in the end you end up with tight or loose valves.

Does it idle good at around 850 rpm?
does it drive good in part throttle?
does it hesitate only in WOT?

 

Yes it drives fine idles 1k and it only does it at wot, idk bout valve lash since i took it to a machine shop so they can install the valves and resurface

 

Any time you remove the head and reinstall it you MUST set the valve lash!!!!!

 

Just checked timing and timing is good, i think i do need a valve adjustment i do hear them ticking more then before, i will b doin that next

 

Does the brand of the AFR gauge matter ? Cuz i found one on ebay for like 18 bucks ??

 

Yea some are not as acurate i would get the innovate mtxl its abut $150 very easy to instal compared to the others like AEM its less wiring and more accurate. Its what i have in my car. Its well worth the money.