User Login    
 + Register
  • Main navigation


Lost Password?

Register now!
Fast Search
Slow Search
Google Ad

Report message:*

Re: Large Valves for H89 head

Subject: Re: Large Valves for H89 head
by rgjt405 on 2022/7/21 16:44:19

Wow, not sure how they're going to fit the 42 and 35 mm valves as there's not enough room between the valve stem centre lines without hitting each other. The sotck distance between the stems center to center is 37.5 mm.
Going with 42 and 35 mm valves is 1.00 mm bigger at 38.5 mm. Your machinist will have to offset one valve guide to make them fit.
Besides, what kind of displacement in the engine do you have with such large valves? Your bottom end response if going to suffer. If you have a high lift and long duration cam, the large valves will give you a lot of top end power but at the sacrifice of midrange and bottom end.
It will be interested to hear back from you as to how that head performs.
Good luck with it as it's going to be an expensive build.