Cylinder Heads - What Matters Most?
05-27-2019, 12:22 AM
#81
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Originally Posted by cmysix
I understand, I was just going to the simplest math for my uneducated mind to grasp.
05-27-2019, 12:22 AM
#82
05-27-2019, 12:42 AM
#84
with my heads TF 220's the difference in flow int .550 306cfm .600 314cfm / ext .550 229 .600 233 you see in my SIG what I've got. So your going to tell me that if my present cam had more lift I would produce much more HP? Texas Speed has several very widely used cams with good results that only have .600 lift. this all goes back to my other question, how much air does a certain bore/stork size really need?
If you are too focused on lift and wary of it you arent up to date on the cam lobe game. You add lobe area with more duration but also more lift. Dont look at this with such narrow focus.
You can add considerable power and extra rpm on stock heads with more lift on nearly any cam.
Those same tsp cams gain considerable power from .550 to .600 so why limit tfs heads? The stockers make more at .600 then why not run the tfs heads at least at the same. You really proved my argument though.
05-27-2019, 12:49 AM
#86
But having talked to tfs on a near weekly basis and selling their heads, those duals are good for .650 lift. If steel id keep it under .630 though. If titanium .650 is fine.
Call and ask the tech guy will likely tell you the same thing.
05-27-2019, 10:20 AM
#88
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"When the moon hits your eye like a big pizza pie....."
05-27-2019, 10:37 AM
#89
If your cylinder head "expert" isn't asking you the following: engine size, max rpm, max lift, intake manifold specs...then find a place that will.
Last edited by YOKED; 05-28-2019 at 09:15 AM.
05-27-2019, 10:40 AM
#90
...it comes down to a velocity thing, just like when talking about a 265 port vs a 305 port, where id imagine the 305 port will usually flow more total than the 265 port head, but at a lesser velocity. but obviously by design the 305 port will naturally have a huge advantage to move more air and doesnt necessarily need more velocity at high rpms to accomplish this, it just needs to be able to get as much air in there which i guess velocity "COULD" play a role here to some extent, so i guess the same could be said for a TB opening. sorry for the rant.
The racing industry learned a long time ago not to invest too much effort into chasing CFM numbers. They ended up with heads that were too big and weren't competitive against smaller heads.
05-27-2019, 11:02 AM
#92
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05-27-2019, 11:43 AM
#93
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Originally Posted by KCS
A lot of power in an NA engine is from continuing to fill the cylinder after BDC. The more velocity the air has coming into the cylinder, the more the cylinder can be filled as the piston is moving up the cylinder. CFM doesn't make power, airmass does. Managing velocity is KING in a powerful NA engine.
The racing industry learned a long time ago not to invest too much effort into chasing CFM numbers. They ended up with heads that were too big and weren't competitive against smaller heads.
The racing industry learned a long time ago not to invest too much effort into chasing CFM numbers. They ended up with heads that were too big and weren't competitive against smaller heads.
Head1 flows 410 on a 305cc runner.
Head2 flows 410 on a 275 runner.
Head2 will outperform head1.
Last edited by Darth_V8r; 05-27-2019 at 12:08 PM.
05-27-2019, 11:59 AM
#94
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I guess port shape on a cylinder head doesn't matter like the LSA on the camshaft.
05-27-2019, 12:44 PM
#96
Guys quick question,
If you have an LS7 engine with CNC LS7 heads and a large camshaft vs the same combo on the exact same engine but a good set of CNC LS3 heads, how much more hp are the LS7 heads worth over the LS3?
(Both engines with a FAST 102mm intake)
This question has been bugging me for a while.
If you have an LS7 engine with CNC LS7 heads and a large camshaft vs the same combo on the exact same engine but a good set of CNC LS3 heads, how much more hp are the LS7 heads worth over the LS3?
(Both engines with a FAST 102mm intake)
This question has been bugging me for a while.
05-27-2019, 02:45 PM
#98
BUT What I am learning from ALL you smarter then I people, and very quickly I might add. You see in my SIG what I've got, I what to stay NA and I'm not a fan of "high lift" I agree with crane cams "quick lift" school of thought get the valve off the seat quickly and close it quickly. I know my cam is small but I'm willing to do ONE more and I'm thinking having one made 231/239 .575/.575 113 LSA 109 ICL thoughts?
05-28-2019, 10:08 AM
#99
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Originally Posted by bortous
Guys quick question,
If you have an LS7 engine with CNC LS7 heads and a large camshaft vs the same combo on the exact same engine but a good set of CNC LS3 heads, how much more hp are the LS7 heads worth over the LS3?
(Both engines with a FAST 102mm intake)
This question has been bugging me for a while.
If you have an LS7 engine with CNC LS7 heads and a large camshaft vs the same combo on the exact same engine but a good set of CNC LS3 heads, how much more hp are the LS7 heads worth over the LS3?
(Both engines with a FAST 102mm intake)
This question has been bugging me for a while.
Originally Posted by 99 Black Bird T/A
Add .050 in lift and you'll have a better cam
Factory ls2 cam is notorious for valve float with only 550 lift. Midrange aftermarket cams like titan4 do not float valves, have faster ramp rates, and more lift.
Not necessarily part of the discussion but good for thought.
05-28-2019, 10:53 AM
#100
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That 12 degree valve angle is superior to the normal 15 degree vavle angle.... I'm go say thats where the extra power comes from mainly.