Valve/valve seat angle?

Performance mods and Advanced Stroker discussion.
Post Reply
car5car
Posts: 1
Joined: November 27th, 2024, 7:25 am
Vehicle Year: 2000
Vehicle Make: Jeep
Vehicle Model: Cherokee

Valve/valve seat angle?

Post by car5car »

99-up valves have very strange specs:
valves 46.5 degrees
seats 44.5 degrees
How can it seal if there is 2 degrees difference?
More important question: can I cut seats with 45 degrees cutter?
What are 99-up and 98-down valve diameters?
Thanks.
User avatar
Cheromaniac
I live here
I live here
Posts: 3214
Joined: March 8th, 2008, 12:58 pm
Stroker Displacement: 4563cc
Vehicle Year: 1992
Vehicle Make: Jeep
Vehicle Model: Cherokee
Location: Cyprus
Contact:

Re: Valve/valve seat angle?

Post by Cheromaniac »

car5car wrote: November 27th, 2024, 7:40 amWhat are 99-up and 98-down valve diameters?
1.91" intake, 1.50" exhaust
1992 XJ 4.6 I6 - 5MT - Stroker build-up, Stroker "recipes" Sold
1995 Mustang GT - 4AT - Modded Sold
2006 Mustang GT - 5MT - Modded Midlife Crisis Car :mrgreen:
75SV!
Noob
Noob
Posts: 16
Joined: January 11th, 2024, 4:07 am
Stroker Displacement: 4.6
Vehicle Year: 2000
Vehicle Make: Jeep
Vehicle Model: XJ

Re: Valve/valve seat angle?

Post by 75SV! »

The different angles helps seal on the outer edge. I had the heads on my LS 5.3 for my Chevy Avalanche done to 37 degrees. The guy doing the set of heads said something like 37 degrees and 38 degrees. I did do 30 degrees to a couple of '99 4.0L heads.
Post Reply

Who is online

Users browsing this forum: Google [Bot] and 0 guests