On a tight budget, want bigger valves. Should I just do the intake and leave the exhaust, as I will not see a big diff with the exhaust valves done?

Plan on running big cams(late closing intake, early opening exhaust), but with small overlap (for big cams).

Should I save that exhaust valve money for something more usefull?

 

What car? For the ITR?

 

Nope. But since you ITR guys are more knowledgable then most forums that I chat on, I'd figure I'd ask ya.

It's for my VR6 actually (ooohhh, ITR's mortal enemy )

Just a general observation, what have youz gained by going with larger exhuast valves?

More for top end performance right?

 

Never saw a need to swap out the ITR valves.

 

VR6's seem more restricted with their intake. I'd do bigger intake valves, but not by much without touching the exhaust valves.

Make sure you at least hit all valve seats and adjacent areas with a little bit of "reshaping" as this will make a bigger difference than just a slightly bigger valve.

 

where is that padlock when you need it???

 

Why? No need to be a *****!

 

Depends on where the restriction in the heads are, and how much of a restriction it is. I would say increase both to the max that will fit, and increase the one that needs it more the most
I know nothing about VR6 motors, but for my 289, I increased the valves from the stock 1.5'' intake 1.4'' exhaust to 2.02'' intake 1.6'' exhaust. Now that I did that, got them ported, screwin studs, with guideplates I think I would have been better off to just fork over the $1500 for some alumiun aftermarket heads.

Basically, I would ask other VR6 guys what to modify first.

 

VW lol

 

Most of the VR6 guys do both bigger intake and exhaust, none that I know of have done only one.

The head will also be ported and matched, along with radiased valve seats, the major restrictions in the VR6 ports is the valve guides and the support boss for it, which will be elimintated to make a smooth port.

Just to give you an idea, the stock intake valve is 39mm, exhaust 34.25mm. The exhaust seem pretty big already, I was thinking of going to a 42mm intake.

What do youz think? ....other then pleaze be constructive

 

It's hard for us to tell you when the question your asking is car-specific.

For Honda Heads, in All-Motor applications, Oversize Valves aren't the best idea...in most cases. This is because of Piston-Valve and Valve-Valve Clearance.

Suprdave

 

Clearance isn't a problem with the cams I plan on using

I've read about a few all motor ITR motor being built with 34mm intakes and 29mm exhaust valves. And the shop I usually buy parts from sell Ferrea valves are selling like crazy for Honda's. Same shop told me not to bother with larger exhaust valves, and have heard the same from a few other builders too, but just wanted to know for sure from a mass audience that doesn't just want my money.

 

33 and 28 which are the stock sizes seem to work the best.
I havent seen any benefits from larger valves on a honda NA setup yet.