big valves for my 1800 head?

[maytag]

[vandor]

> and how large can I go with this head casting?

That will depend on how many times the head has been surfaced, and how much space is left between the intake valve seat and the surface of the head.
I would think it would help with performance if you have hi-po cams, but I doubt anybody has done any dyno testing of exactly the same engine with and without the big valves...

[maytag]

[So Cal Mark]

we've done comparison testing on an engine with a head with stock valves and the same engine with our oversize valves. The same cams were used. We noticed a significant hp increase from 5000rpm on up with the big valves without a dropoff in low or midrange. The customer that owns this car noticed the power increase on his first drive.

[Daniel]

we've done comparison testing on an engine with a head with stock valves and the same engine with our oversize valves. The same cams were used. We noticed a significant hp increase from 5000rpm on up with the big valves without a dropoff in low or midrange. The customer that owns this car noticed the power increase on his first drive.

do you have the dyno results maybe you can post them would be nice to see the difference .

[So Cal Mark]

no, we didn't dyno this motor before the swap only afterwards.

[wmausbach]

So what did you get? I would like to know for realtive increase as I'm planning the same modification?
Ciao
Wayne

[maytag]

so.....
on the advice of my "motor-mentor" and cam-grinder extraordinaire, I ordered the standard valves. The reasoning being that this particular build, all they would be is a bigger disc to try to flow around.... And there's alot of sound reasoning there.

However:
after installing said new valves this evening, I discovered that I was shipped the larger "performance" 43mm intakes and matching larger exhaust valves. They are beautiful. but they're wrong for me. :sigh:

So I'm back on "hurry-up-and-wait" mode.
I guess tomorrow I'll get back to the wiring again.
I'd sure like to get this motor completed someday. IF I miss the spring driving weather, I'm-a gunna be so pissed at myself....
It's been almost 60 days since I removed it. I'm about 6 weeks behind schedule with seemingly one delay after another. I suck at stuff that I can't control.