I posted this on another board as well didn’t seem to get much response… Anyone care to shed some light on the discussion of the benefits from oversized valves… I figure heck I’m spending $175 on valvesprings, maybe I should also get some oversized valves. This head buildup is on a budget, but if it’s a definate worthy upgrade I may consider it… Any before afters? TIA
In short, no. To get effective use with oversized valves, you need to have your valve openings enlarged and porting to get head flow characteristics to match. Definitly not a low budget option.
tom
real9999: I am rebuilding my head, getting it ported, polished, decked, and a 3 or 4 angle valvejob…
hmmmm
Just go with, valve springs, retainors, StainlessSteel Valves, Cams, Sprokets, and some mild headwork, in which you are doing, like valve job, port and polish, port matching your intake manifold to your head…etc…dont use money on the extra head work for the valves…unless of course you have a full blown RaceCar…do the basic headwork first…late:rolleyes:
VR-BottleFedTeg: What experience do you have with building LS engines, VTEC engines & headwork? Just curious to know what to base your suggestions of changing OEM valves in perfectly fine shape for brand new stainless steel valves, ESPECIALLY when brand new stainless steel valves in OEM diameter and 1mm oversized diameter are the same price…
well…
I just finished building my 1997 B18B motor, all motor / 120 shots of NOS
So im pretty familiar…SS valves if your going all motor probably isnt needed, but if you plan to run higher RPMs like G2icGURU, then get the headwork done, like I said…
Im talking about 9000+ RPMS…go with Crower, best stuff on the market…late
Originally posted by teg92
VR-BottleFedTeg: What experience do you have with building LS engines, VTEC engines & headwork? Just curious to know what to base your suggestions of changing OEM valves in perfectly fine shape for brand new stainless steel valves, ESPECIALLY when brand new stainless steel valves in OEM diameter and 1mm oversized diameter are the same price…
The stainless steel issue is more of a durability issue in preventing burnt valves. There’s no relation to flow. The word that comes to mind with SS valves is nitrous. The question to ask is whether switching to oversized valves will provide any benifits (or repercussions) to air and fluid flow. Keep in mind that airflow and also fluid mechanics are complex phenomenon and as in exhaust diameter, bigger isn’t always better. Also, most off the shelf aftermarket cams are designed with stock valves in mind. In the end though, the person you should really be asking is the person doing the head porting. He or she is who’s going to make the difference. Ask if they have experience bench, dyno, and track testing with your setup. If they really know what they’re doing, then they should be able to tell you whether or not you should move to oversized valves.
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tom
Finals are done and I’m drunk. But still sober.