So here is the run down...I bought a set of Portflow SS valves (in. and ex.) from a member here on the boards. I was told by the seller via pm, and it was stated in their FS thread, that they were b-series valves, brand new, and Portflows. Here comes the problems...

Yesterday I went to the machine shop to pick up my b16 head that I had just dropped off last week for a clean, resurface, standard valve job, and install of the Portflow valves, RM valvetrain, and new OEM valve seals. When I got to the machine shop, Chris, the owner, informs me that the exhaust valves look as if they had been hand lapped into a head before at some point, all but the one #'ed 7 had been tipped, and that there was no way the exhaust valves would fit b/c the stems were too big...TOO BIG? He shows me how the intake valves will slide right in the head and then how when he tried to put the exhaust valves in, the get to the guides and stop. Upon inspecting the old OEM exhaust valves to the new Portflow valves, I see what he is talking about...Here is a pic for ref (notice how much larger the Portflow stem is compared to the oem exhaust valve stem):



Now, my question is this...Both the old oem exhaust valve and the new Portflow valves are the exact same height when stood up. Both valves have the same size heads. Why would the stem of the new valves be that much larger than the old oem valves? I have never heard anyone speak of aftermarket ss valve stems being larger than the intakes or anything of that matter....

Next...I was told these were brand new, Portflow valves. As I was comparing one of the new intake valves to one of the new exhaust valves, I noticed that at the top of the stems on the intake valves they have "REV" on them. I know that Portflow no longer sells valves by Portflow but I do know they sell and use "REV" valves. Are these the same valves just Portflow uses the REV name for their valves? And why would only the intake valves have "REV" on them and not the exhaust valves?

If anyone could give me some insight here as to why the stems of the exhaust valves are much larger than the new intakes and the old oem stems I would greatly appreciate it! If someone knows they are for a different motor, I would like to know that also! TIA!

 

Just measured the stem size on the new exhaust valves and the old OEM exhaust valves. Here are the measurements:

Old OEM exhaust valve stems - 5.45mm or 0.215in
New "Portflow" exhaust valve stems - 6.54mm or 0.257in

Comes to a difference of 1.09mm (0.043in) larger than old oem exhaust valve stems

Also measured the height of the new exhaust valves and the old OEM exhaust valves. Here are those measurements:

Old OEM exhaust valve height - 101.67mm or 4.060in
New "Portflow" exhaust valve height - 101.37mm or 3.991in

 

From the looks of it, it looks like you were sent exhaust valves for a “b’series” LS head.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ToeJam &raquo;</TD></TR><TR><TD CLASS="quote">From the looks of it, it looks like you were sent exhaust valves for a “b’series” LS head. </TD></TR></TABLE>

Humm...Can anyone confirm?

I have a LS head in the garage but I believe the valves are locked in the head. I will have to go check and if not, test it out. Thanks for the reply!

 

Is there any way to look up the specs on different B-series heads? Like valves sizes and such....

Like ToeJam said, they could've been for an LS.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AnToNy &raquo;</TD></TR><TR><TD CLASS="quote">Is there any way to look up the specs on different B-series heads? Like valves sizes and such....

Like ToeJam said, they could've been for an LS. </TD></TR></TABLE>

You're right Ant. I thought about that last night after I showed you the pics. If they are for a LS thats cool I can just sell them and buy a set of exhaust valves for my b16 head. I just need some confirmation...

Hold the hell on...I have a zip-loc bag full of ls intake and exhaust valves....I am going to go measure them right now. Be back with my findings

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Trock1029 &raquo;</TD></TR><TR><TD CLASS="quote">

You're right Ant. I thought about that last night after I showed you the pics. If they are for a LS thats cool I can just sell them and buy a set of exhaust valves for my b16 head. I just need some confirmation...

Hold the hell on...I have a zip-loc bag full of ls intake and exhaust valves....I am going to go measure them right now. Be back with my findings </TD></TR></TABLE>

I'll be a summa-biotch!!!!!!!!!!!!!!!!

Exhaust valves from the zip-loc bag measured out to be 6.54mm Now the question is how much could I get rid of these for? I know Chris at the machine shop resurfaced the new SS valves...