Extrude-honing 99+ intake & other bright ideas

How is there no real benefit?

Not an XJ but on my Barracuda I went from a 2.02 intake to a 2.05 intake and it shaved .2 off of my 1/4 mile time :). Well worth the money as it was only like $300 or so with the valves to do.
 
SBC valves are sized for way more flow than even most strokers would need. Perhaps with the right cam lift / duration you could see gains in top end but I think the stock valve sizes flow plenty for what the 4.0 or even 4.7 stroked cylinders can take & burn.

But hey - what do I know?
 
BlueCuda said:
How is there no real benefit?

Not an XJ but on my Barracuda I went from a 2.02 intake to a 2.05 intake and it shaved .2 off of my 1/4 mile time :). Well worth the money as it was only like $300 or so with the valves to do.
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x2. No real benefit? That's like sayin there's no real benefit in a CAI. You won't see more than 5 hp TOPS from a CAI yet it's one of the first mods people do.
 
I was contemplating the 1.97"in and 1.60"ex mopar ss tulip valves when I built my stroker(used the $200 elsewhere). From what I've read, the intake manifold can't take advantage of the 2.02"in due to the runners. You also have shrouding issues with the larger valves. I did unshroud my head a bit during the port and polish.
 
PurpleCherokee said:
x2. No real benefit? That's like sayin there's no real benefit in a CAI. You won't see more than 5 hp TOPS from a CAI yet it's one of the first mods people do.
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Then go get some installed. They will go well with your restrictive exhaust. Maybe you should suggest them to your friend to help that compression loss he has through his valve seals.
 
Restrictive exhaust what?? I'm pretty sure the argument has always been whether or not it's TOO free-flowing. Just get over it and admit that you're wrong about oversize valves being without benefit.
 
PurpleCherokee said:
Restrictive exhaust what?? I'm pretty sure the argument has always been whether or not it's TOO free-flowing. Just get over it and admit that you're wrong about oversize valves being without benefit.
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This coming from the person that thinks you can lose compression through the valve seals. :twak:
 
Taken from a PM I had with Dr. Dyno,
My advice would be to stick to the stock valves and the stock valve springs/retainers/locks. The ports in the heads aren't big enough to make the most of oversize valves
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This was when I was buying stuff for my 4.6 stroker build. The exhaust ports in the head are more restrictive than the valves. In the guys Cuda? Im sure theres benefit there. Not so much here, he even said not on an XJ.
 
PurpleCherokee said:
"At the time, the ultimate cylinder head conversion was the Accurate Power big valve head with 2.02" intake/1.60" exhaust valves. This produced a dyno-proven 16hp gain on a stock 4.0L engine and a 22hp gain on a 4.6L stroker engine."

Quit being dumb guys, bigger valves are gunna get more air into your motor. Yes, even on an XJ...
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Then go spend the money and tell us how it works out. We are expecting dyno sheets, which I have. Put your money where your mouth is stupid.
 
Lets compare apples to apples. The accurate power head was not a Jeep head. It was a completely redesigned piece with different ports that were engineered for more flow. It, could take advantage of bigger valves. If I remember correctly the new Hesco head does not use bigger valves. Accurate went out of business and Hesco is the golden shrine of Jeep performance. Put bigger valves on your 7120, 0360 or 0331 head. You wont get any results, and you wont beat any WJs.
 
PurpleCherokee said:
Will do. Hope your words taste good :D
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You have 3 people here experienced with strokers and other such performance modifications telling you there is no benefit. Why are you so stupid that you won't listen to either of them? Why did you even bother saying anything if you are always right? The only thing you have experience is with your pos convoluted exhaust system and valve seals that leak compression. Just do everyone a favor go waste your money on this mod because its your money and a fool and his money are soon parted. And don't bother reporting back with your failed results because no one cares. Yeah,. that's also a lot of weight to add to the valve train for no gain... but you know what more weight does to the valve train too...
 
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Accurate Power's heads were reworked stockers with SBC 2.02/1.60 valves. While they flowed more air at higher valve lift numbers, the bigger valves caused shrouding and the low lift numbers weren't so good, and it's at lower lifts where most of the torque is made and where the engine spends the most time. Stock sized valves work best. The intake/exhaust ports simply aren't big enough to take advantage of oversize valves.
 
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Just so we can keep this going. . .for a forced induction app, would those bigger valves be recommended/necessary to get all that air in and all that exhaust out? Tulip valves? Is a stainless steel intake valve harder/less prone to bend/able to handle higher pressures better?
 
Im going to say forced induction or not, unless you have your head ported, at least on the exhaust side, it wouldnt make much of a difference because the valves are not the bottle neck.
 
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