I'm getting my head ported and polished in a few weeks, and since im taking the head out i plan to get some oversized valves as well. My Questions are, who do I get the valves from, for best power increase and how much will they effect power with an agressive port and polish.

Mods:
Big gun full exhaust
pro flow foam, no lid
dyno jet kit 190:185
high grind web cam - springs
11:1 piston

 

I agree with what air recommended. Any time you can move more air and fuel through the engine it has the potential to make more power if everything else is set up and done right; so I would say get the big valves while you are in there. Two friends of mine each have 727 Raptors the only thing different in the motors is the size of valves they have and the one with the big valves runs about 2/10ths faster than the other. The only other exception between the two is the one with the big valves also runs an aluminum axle and I know this is making a difference but I still say put them in there to have a motor that has the potential to make more power. Give Bob Craycraft a call and he can help with the big valves. Slim

 

PERSONALLY, I DONT think Oversized valves are worth the money. UNLESS you plan on going 700 + CC's. only then will you see a small difference in power.

I have ran Numberous Stage 3 Rappys and DS's and believe "over-sized" valves are "OVER-RATED". my.02.







Bigger.

 

TRY POWROLL RACING.COM they have over sized s/s valves. and try TRINITY RACING.COM they have oversized valves and stuff that they say you could have another 3horsepower. so you will be getting maybe 3-5 horsepower.

 

With running oversized valves, wont he have to get 35 or 39 mm FCR carbs or something similar? With the rush of air and exhaust I would think he would have to get a carb to keep up as well. Right? or if someone can correct me on this go ahead.

 

I have never heard anyone say- "look at that big valved raptor run" That said, if you are only building a drag raptor go for it.

 

So, I'll need to have my piston recut so that the valves dont hit the piston [img]i/expressions/face-icon-small-sad.gif[/img] thats a bad day. Right now i think i have the biggest cam that webcam makes. Any Valve brands recommended?? How many jet sizes will i have to jump up on with an agressive port and polish with these bigger valves?

 

Makes you wonder how Trinity can claim all that power gain by going to a larger center valve. I've always wondered about valve size vs. degree of engine build. Isn't larger valves one of the last mods you should make? I would think that the extra money towards FCRs would be more worthwhile. I'm not an engine builder, though, so I could be wrong.

 

Hmmm, im going to wait on the valves then.... ill get the port and polish and work on getting the carbs... FCR's make a big diference with the mods i have, or only when you go into the big bores, and get the bigger valves..... Will I have to buy new filters to fit the new carbs?

 

Air, how many valves????