Camshaft for Gen7 BBC...
#1
Thread Starter
Registered
Joined: Sep 2022
Posts: 172
Likes: 124
From: Dawsonville, GA
Im still dicking around with this 8.8 build and now looking at camshafts a little bigger than the 496HO cam I currently have.
This build is a 4.350 bore x 4.500 stroke. 10:1 forged flat tops.
Heads are yet to be settled on, but will likely be the PSI heads with much flatter valve angles.
This is the cam im looking at now...
Thoughts on reversion with wet exhaust ? and possible ideas to mitigate it without running dry to the tips ?
https://www.compcams.com/xtreme-marine-242-248-hydraulic-roller-cam-for-chevrolet-big-block-gen-vi.html
This build is a 4.350 bore x 4.500 stroke. 10:1 forged flat tops.
Heads are yet to be settled on, but will likely be the PSI heads with much flatter valve angles.
This is the cam im looking at now...
Thoughts on reversion with wet exhaust ? and possible ideas to mitigate it without running dry to the tips ?
https://www.compcams.com/xtreme-marine-242-248-hydraulic-roller-cam-for-chevrolet-big-block-gen-vi.html
#3
The cam you have listed is a Gen VI cam???
Your best info will probably come from Raylar Vortec 8100 8.1L Chevy GM Performance Parts - GEN 7 Big Block - 496MAG HO Marine Performance Parts - Raylar Engineering
Your best info will probably come from Raylar Vortec 8100 8.1L Chevy GM Performance Parts - GEN 7 Big Block - 496MAG HO Marine Performance Parts - Raylar Engineering
#4
Registered

Joined: Nov 2006
Posts: 1,313
Likes: 153
From: Tygart Lake, WV
Im still dicking around with this 8.8 build and now looking at camshafts a little bigger than the 496HO cam I currently have.
This build is a 4.350 bore x 4.500 stroke. 10:1 forged flat tops.
Heads are yet to be settled on, but will likely be the PSI heads with much flatter valve angles.
This is the cam im looking at now...
Thoughts on reversion with wet exhaust ? and possible ideas to mitigate it without running dry to the tips ?
https://www.compcams.com/xtreme-mari...ck-gen-vi.html
This build is a 4.350 bore x 4.500 stroke. 10:1 forged flat tops.
Heads are yet to be settled on, but will likely be the PSI heads with much flatter valve angles.
This is the cam im looking at now...
Thoughts on reversion with wet exhaust ? and possible ideas to mitigate it without running dry to the tips ?
https://www.compcams.com/xtreme-mari...ck-gen-vi.html
I have no experience with the 8.8 heads and PTV clearance. On the 8.1 you can't run much bigger than the HO cam on the stock small valve relief flat tops.
#6
Registered

Joined: Nov 2006
Posts: 1,313
Likes: 153
From: Tygart Lake, WV
#7
Registered

Joined: Feb 2009
Posts: 8,356
Likes: 1,515
From: NW Michigan
Now I recall. I hadn’t kept up on the entire thread however post 56 stands out. Pretty impressive and seems like a custom grind would be best option. Probably not an old school one either. Be interesting to see what comp would come up with. How large are the int runners on those heads?
#8
Thread Starter
Registered
Joined: Sep 2022
Posts: 172
Likes: 124
From: Dawsonville, GA
With the 15 degree valve angle in the PSI heads... PTV clearance is not an issue.
With the 496HO cam and 1.8 rockers @ .540lift there is a ton of clearance. I've clayed them already and had so much room (.250+) I didnt bother measuring.
The ports, valve angles and chamber shape make them far superior to the cathedral port heads.
#9
Thread Starter
Registered
Joined: Sep 2022
Posts: 172
Likes: 124
From: Dawsonville, GA
Now I recall. I hadn’t kept up on the entire thread however post 56 stands out. Pretty impressive and seems like a custom grind would be best option. Probably not an old school one either. Be interesting to see what comp would come up with. How large are the int runners on those heads?
I've contacted them twice via email. Got one reply asking questions, I answered and never got a response back.
I dont have a ton of cash into these engines... so a typical off the shelf cam will be fine.
I already have the XM296HR on my workbench.
If the reversion issue cant be resolved using some creative exhaust mods, I will just stay with the HO cam and see how it runs in the boat. I can still use the bigger cam anyway since I have a 2nd one Im building for my kids pickup truck.
#10
Registered

Joined: Nov 2006
Posts: 1,313
Likes: 153
From: Tygart Lake, WV
I dont have a ton of cash into these engines... so a typical off the shelf cam will be fine.
I already have the XM296HR on my workbench.
If the reversion issue cant be resolved using some creative exhaust mods, I will just stay with the HO cam and see how it runs in the boat. I can still use the bigger cam anyway since I have a 2nd one Im building for my kids pickup truck.
I already have the XM296HR on my workbench.
If the reversion issue cant be resolved using some creative exhaust mods, I will just stay with the HO cam and see how it runs in the boat. I can still use the bigger cam anyway since I have a 2nd one Im building for my kids pickup truck.



