Help Me Pick Good Flowing Heads
well to give you an idea, i van get the AFR 205s with 63cc for $1,900 even (including shipping and tax) Like others have stated, the 5.3s do not flow that well up top, granite my car is not up at the top that often, but when it is i want it to shine. I already have PRC dual valve springs b/c like you said i am close to .600 lift. my cam package has 6k miles on it.
I just want to get my DCR back up, and gain some low end TQ... That is why i was thinking the AFRs w/63cc chambers with a .040" head gasket will do that...
I just want to get my DCR back up, and gain some low end TQ... That is why i was thinking the AFRs w/63cc chambers with a .040" head gasket will do that...
My 5.3L heads are 62cc, my cam is .595/.598" lift. i used MLS gaskets from the GM kit without issues. Texas Speed recommended them over the Cometic .040" ones, since I didnt really plan on doing much with the car as far as track/strip goes, just wanted a fun street car
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that is an awesome deal! It sounds like it'd be tight tho with PTV, though I'd doubt there would be problems. Might want to go with GM gaskets though, just a bit thicker, in case the PTV issue arises with the .040 gasket..
My 5.3L heads are 62cc, my cam is .595/.598" lift. i used MLS gaskets from the GM kit without issues. Texas Speed recommended them over the Cometic .040" ones, since I didnt really plan on doing much with the car as far as track/strip goes, just wanted a fun street car
My 5.3L heads are 62cc, my cam is .595/.598" lift. i used MLS gaskets from the GM kit without issues. Texas Speed recommended them over the Cometic .040" ones, since I didnt really plan on doing much with the car as far as track/strip goes, just wanted a fun street car
Why would the PTV clearance be so tight? my cam is not that big. i want to run jsut a little bit thinner of a headgasket jsut to bump compression.
Obviously the head designs are going to be slightly different, as mine are a set of basically stock heads (a GM product, certain to work right under known circumstances and situations with many many cam/gasket/pr/rocker combos), and the ones you're considering are an independent design, but I say PTV would maybe be tight because there's currently only a 1cc difference between my heads and the ones you're mentioning. divide that volume by the square centimeter-age of the surface area on that cylinder head and you've got a very very small difference in height when comparing our two different styles. There could be differences in the valves as well (and by could be i mean most likely are), like size or depth they are set in, which could present problems.
I'm not saying you'll have a problem, your lifts are equal to or under mine. It would likely be fine with the .040" gasket, but I was advised against that by some pro's that know what product they sold me. Give the folks at AFR a call and pretend like you're interested in buying a set of heads from them and give them your cam specs to see how they feel about which gaskets to run or if you'd be able to mill them. I'd say a thinner gasket would be better than milling, because I've heard it helps something called "quench" that is too technical for me to want to try to understand especially this late in the evening for me. Also, if you decided to sell the heads later for whatever reasons, you won't have problems trying to sell milled heads to people that want unmilled ones. Do call AFR tho, or TrickFlow, whoever was making the heads you were looking at.. lol
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I ordered a h/c combo from texas speed about a year ago, the heads i've mentioned with the torquer v.2 cam; its 232/234, .595/.598" lifts on 112 LSA, thats about all i remember without breaking my leg looking for the card that came with it.
Obviously the head designs are going to be slightly different, as mine are a set of basically stock heads (a GM product, certain to work right under known circumstances and situations with many many cam/gasket/pr/rocker combos), and the ones you're considering are an independent design, but I say PTV would maybe be tight because there's currently only a 1cc difference between my heads and the ones you're mentioning. divide that volume by the square centimeter-age of the surface area on that cylinder head and you've got a very very small difference in height when comparing our two different styles. There could be differences in the valves as well (and by could be i mean most likely are), like size or depth they are set in, which could present problems.
I'm not saying you'll have a problem, your lifts are equal to or under mine. It would likely be fine with the .040" gasket, but I was advised against that by some pro's that know what product they sold me. Give the folks at AFR a call and pretend like you're interested in buying a set of heads from them and give them your cam specs to see how they feel about which gaskets to run or if you'd be able to mill them. I'd say a thinner gasket would be better than milling, because I've heard it helps something called "quench" that is too technical for me to want to try to understand especially this late in the evening for me. Also, if you decided to sell the heads later for whatever reasons, you won't have problems trying to sell milled heads to people that want unmilled ones. Do call AFR tho, or TrickFlow, whoever was making the heads you were looking at.. lol
Obviously the head designs are going to be slightly different, as mine are a set of basically stock heads (a GM product, certain to work right under known circumstances and situations with many many cam/gasket/pr/rocker combos), and the ones you're considering are an independent design, but I say PTV would maybe be tight because there's currently only a 1cc difference between my heads and the ones you're mentioning. divide that volume by the square centimeter-age of the surface area on that cylinder head and you've got a very very small difference in height when comparing our two different styles. There could be differences in the valves as well (and by could be i mean most likely are), like size or depth they are set in, which could present problems.
I'm not saying you'll have a problem, your lifts are equal to or under mine. It would likely be fine with the .040" gasket, but I was advised against that by some pro's that know what product they sold me. Give the folks at AFR a call and pretend like you're interested in buying a set of heads from them and give them your cam specs to see how they feel about which gaskets to run or if you'd be able to mill them. I'd say a thinner gasket would be better than milling, because I've heard it helps something called "quench" that is too technical for me to want to try to understand especially this late in the evening for me. Also, if you decided to sell the heads later for whatever reasons, you won't have problems trying to sell milled heads to people that want unmilled ones. Do call AFR tho, or TrickFlow, whoever was making the heads you were looking at.. lol
The 5.3L heads have smaller combustion chambers already than the LS6 heads. They don't flow quite as well either up top in RPMs I don't think, but they're pretty close to similar. Most vendors that sell cams and heads will be able to guide you with whether or not you'll have enough PTV clearance. Whenever you get everything put together tho, you can check it to make sure by leaving the spark plugs out and turning the engine by hand with a cheater bar (big pipe or some other longer piece of metal to turn a wrench on the crank bolt). If everything spins over freely, and nothing sounds like its binding or hitting metal on metal inside the head area then you're good to go!
plus say nothing hits...you could have .001 clearance or .120 clearance you wouldnt know...tight PTV clearance on the intake side is around .050 and exhaust is .080...i personally would not go closer than .070 intake and .090 exhaust...
The proper way to check PTV clearance get some clay from a craft store...clay a piston, use your old head gasket and 4-6 head bolts, tighten the head down spin the motor over a couple times, remove the heads, and carefully scrape away the the clay off the piston...section it with a razor blade to the thinnest spot and measure both valve relief marks with a caliper...
some people like using check springs if they dont wanna remove the heads with a cam only setup, but if you are going to remove the heads this is the best method...
If you havent degreed your cam i would check to make sure that is true too...they sell a kit on jegs or summit for around $100
FYI my cam clearance was around .086 on the intake and .110 on the exhaust and my cam is only 230 230...stock mls head gasket too
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That is not the proper way to check PTV clearance...no way in hell i would do it that way...the mechanics of a motor change alot at 6K RPM over just turning it over by hand...
plus say nothing hits...you could have .001 clearance or .120 clearance you wouldnt know...tight PTV clearance on the intake side is around .050 and exhaust is .080...i personally would not go closer than .070 intake and .090 exhaust...
The proper way to check PTV clearance get some clay from a craft store...clay a piston, use your old head gasket and 4-6 head bolts, tighten the head down spin the motor over a couple times, remove the heads, and carefully scrape away the the clay off the piston...section it with a razor blade to the thinnest spot and measure both valve relief marks with a caliper...
some people like using check springs if they dont wanna remove the heads with a cam only setup, but if you are going to remove the heads this is the best method...
If you havent degreed your cam i would check to make sure that is true too...they sell a kit on jegs or summit for around $100
plus say nothing hits...you could have .001 clearance or .120 clearance you wouldnt know...tight PTV clearance on the intake side is around .050 and exhaust is .080...i personally would not go closer than .070 intake and .090 exhaust...
The proper way to check PTV clearance get some clay from a craft store...clay a piston, use your old head gasket and 4-6 head bolts, tighten the head down spin the motor over a couple times, remove the heads, and carefully scrape away the the clay off the piston...section it with a razor blade to the thinnest spot and measure both valve relief marks with a caliper...
some people like using check springs if they dont wanna remove the heads with a cam only setup, but if you are going to remove the heads this is the best method...
If you havent degreed your cam i would check to make sure that is true too...they sell a kit on jegs or summit for around $100
and my cam was installed dot to dot, even though it was cut on a 110+4... If the cam were to be degreed, would i gain any HP?
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Verdad Gallardo if you retard it or advance it, it will just shift your powerband up or down 100 or so RPMs...doesnt really affect the number that much though...
your statement doesnt really make sense...the 110+4 means that it is on a 106 ICL and 4* is already ground into the cam...so with it installed dot to dot it is 110+4...if you retard the cam you will gain intake clearance but lose exhaust...and vice versa if you advance it...lose intake clearance and gain exhaust...
if you retard it or advance it, it will just shift your powerband up or down 100 or so RPMs...doesnt really affect the number that much though...
if you retard it or advance it, it will just shift your powerband up or down 100 or so RPMs...doesnt really affect the number that much though...
0.100 67 54
0.200 139 120
0.300 219 179
0.400 271 224
0.500 308 248
0.550 315 255
0.600 320 260
The AFR's are great But get what you want out of them will take some money (more then just buying the head ) I was looking at going the same way with the afr's but with the money i would put into them i can Just get TFS 215's milled and rocker's for the same so i am but not till i max out the car cam only then my 243's are going to tea to get the stage 2.5 done to them.
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^^^ haha agree 100%, when you put the motor together you should ALWAYS check it even tho you think you have enough. a 20 minute safety check is not worth a big oopsy down the road. If you do mill the heads, whatever you decide I would actually check the PTV before you mill it just to get a baseline reading. but anyway sounds like a sweet build!
^^^ haha agree 100%, when you put the motor together you should ALWAYS check it even tho you think you have enough. a 20 minute safety check is not worth a big oopsy down the road. If you do mill the heads, whatever you decide I would actually check the PTV before you mill it just to get a baseline reading. but anyway sounds like a sweet build!
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It isnt just about the flow number of a the head, velocity makes a huge difference.
For the price of the AFR's you quoted this is a no brainer!!
As far as the cam do yourself a favor and have a custom one ground.
For the price of the AFR's you quoted this is a no brainer!!
As far as the cam do yourself a favor and have a custom one ground.
also how are you supposed to disect the tootie and measure the clearance then because the wrapper will add clearance so you wont know an exact number clearance wise...
but i guess you do get to eat the tootsie roll when you are done lol
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