MYSTERY Ported Heads

It's a huge concern lol. Especially since this was a rebuild of the heads which means recutting that seat again. I'm running lead substitute religiously and praying they last.

I'm not sure but my guess is the tip is how far down from the end the keeper seat is?

Now that I look at it the numbers they do tell the story about intense valves. They changed them at some point to slightly longer 4.750. The valves are modified Manley parts. You can't buy them from anywhere but intense. I don't know how everybody else's valves are though so still can't confirm even what kinda valves you have

Well, here's a bit of hope. If the "tip" is what you're saying it is, then something is finally making sense! He measured my tip at .160", which I'm sure could be very slightly off because getting calipers in there to measure that would be difficult.

So, if we take your tip length minus my tip length (.1750-.160) we get .015. (Sorry, don't know how to make that not sound dirty lol)
If your intake valve valve is 4.725", and we subtract that difference in tip measure, we would get 4.710"!

It now seems VERY likely that whoever built the heads bought the Intense Manley valves from back in the day and ground them a bit. For what reason, I do not know. I think that will be my course of action, proving they still have access to the shorter valves that they used to use?

I wouldn't count on getting your hands on old valves from them. It's been a good while since they changed and it's hard to even get answers on old stuff much less parts. If you have to go with taller replacement valves, you can shim up the rockers to accommodate but then you need to also have longer pushrods to reach the higher rocker position (about twice the length you shim the rockers up) - all to maintain the same geometry and lifter preload. I have a pair of ground shims I made as a just-in-case thing for me when i was getting my heads done last year or whenever it was. If you end up needing that shimming, I can grind them to whatever thickness you need and ship them to you.

Ok cool. So, would the amount of shimming I would need for the rockers be the same as the difference between current and replacement valves?

I actually pulled a stock head off of my 98 parts riv today, and I'm going to measure that and see how it compares to these. I Would have to imagine that factor directly into how long of pushrods I would need as well.

Valve-piston clearance isn't really an issue for me, is it? With my rockers I'm getting arourn .500 or lift I think, and some cams go to like .600, so I don't think I would have any concerns there unless the heads are milled a lot, which I doubt.

I'll definitely have to let you know about those shims. So, if the diffence between my valves and the ones they sell now is .040", could I just have the heads milled down to that and just buy new valves and pushrods and not worry about shimming?

It's hard to say exactly how much is ideal to shim. I would not shim the whole difference of the valve length personally, I would go a bit less because you know that with the bigger cam, the rocker is going to end up swinging farther over than it ever did before meaning the central position of the rocker is different. I'd play on that a little bit and try to get it as neutral as possible to where the rocker rests a little farther over and peak-lifts a little father over instead of trying to maintain the exact same rest position and have it swing much farther one way. I think that's a good approach to keep mating parts happier. Unfortunately having 1.6(avg) ratio on one side makes it a little trickier and rather than fighting with math vs reality I'd just assume shim the rockers like half the length difference of the valves (stock vs your final installed height of the new valves), visually make sure it looks good, and then once you have the heads bolted on with the gaskets and everything, you can figure out what you need for pushrods. I wouldn't even bother trying to guess that ahead. One of those dummy pushrod length checkers comes in real handy for this although I've gotten away without it so far because my changes haven't been so extreme that whatever pushrods I had didn't at least fit enough to figure out what I need.
Sorry - a lot of shit here. The complication is mostly the longer valve stem high but you can make it work.

Shouldn't have any valve-piston problems. For a rough reference, an IS4 blower cam which has a crap ton of duration and .600 lift comes within like .040" of the piston. I would like to assume anything with less cannot be a problem although I don't know how critical crank-cam timing is in that recipe and it is very much an interference motor. Meaning I don't know if you'd be in trouble with advanced/retarded cam timing or a little bit of valve float. No one ever runs cams retarded or advanced though. Just make sure the springs are more than enough for the setup.

just found this. Thought it might be relevant?
part 2 of 3

Alright, so this is super cool... Ordered my valves, got them in the mail, cool! So then there's this... Sorry for my phone's awful camera.

1.9" intake valve that was in head:

"1.9"" intake valve from wbs:

1.57" exhaust valve that was in head:

"1.57"" exhaust valve from wbs:


So, I'm confused. Is measuring the diameter of the valve not the way that the valve is measured? Lol

One good thing, the stems of the new valves measured .314" while the ones that were in the heads measured .313". I'm guessing this is a good thing since the guides and seals wear a little bit over time.

"wbs" as in W Body Store?

Yes sir. It was either these or the intense Manley valves, and considering I'm not building a 600hp track monster, I figured these would be good enough.

These heads are a "head"ache

Aside from the fact that the valves aren't even close to the same size, does it matter that the head of the replacement valves are considerably thinner? Also, the original intake valves have that indent, whereas the replacements are pretty much flat on the bottom. Is that ok? I didn't weigh them, but the new valves seem a lot lighter, which I'm assuming is good?

WBS emailed me back and said they definitely got the wrong parts from their supplier. They emailed me a prepaid label, and said that if I mailed the valves back they'd get me the correct ones.

Cool!