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  #31 (permalink)  
Old 01-16-2013, 01:12 PM
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Pro-Filer Performance Products
If your looking at brodix ik's, or even pro comp's. Check here first....or here
Speier Racing Heads

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  #32 (permalink)  
Old 01-16-2013, 01:14 PM
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And if you tell Chad at speier racing heads your issue with dome piston and detonation he can Taylor to your combination, at a price that will likely suprise you.
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  #33 (permalink)  
Old 01-16-2013, 01:54 PM
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Quote:
Originally Posted by Caballerokid View Post
All very true, but I have heard running aluminum heads since they cool more rapidly than steel will run cooler and effectively act as if you have one less point of CR such as 10:1 steel and 9:1 aluminum. Is this not the case? Like I said previously, I have no problem running race fuel I have already implemented a blend but I plan to run more of a blend if not straight race fuel.
aluminum is a little more detonation resistant then iron but to think you can get away with over 11:1 with pump fuel isn't going to happen on a standard sbc.
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  #34 (permalink)  
Old 01-16-2013, 02:50 PM
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aluminum is a little more detonation resistant then iron but to think you can get away with over 11:1 with pump fuel isn't going to happen on a standard sbc.
Well if the cam is right it will run. Alum heads will make it possible but with anything careful tuning will be needed to make it run correctly on pump gas.

Comp 294s or bigger might be needed have to cc the heads and crunch the numbers. But it is Possible.

Pop ups are usally a little more detonation resistence. With a good squish band it should be ok. I think sunco 94 would be the most you would need with a proper tune.

87 octane is out of the questioon im sure.
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  #35 (permalink)  
Old 01-16-2013, 03:24 PM
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Originally Posted by hcompton View Post
Well if the cam is right it will run. Alum heads will make it possible but with anything careful tuning will be needed to make it run correctly on pump gas.

Comp 294s or bigger might be needed have to cc the heads and crunch the numbers. But it is Possible.

Pop ups are usally a little more detonation resistence. With a good squish band it should be ok. I think sunco 94 would be the most you would need with a proper tune.

87 octane is out of the questioon im sure.
pop up have less detonation resistance. And if you make it rich enough and pull out enough timing it'll run fine but it'll be down about 50hp. loading plays a big factor as well, a 4.56 rear in a light car like a pinto with a high stall and it'll be fine even with an optimal tune for power.
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  #36 (permalink)  
Old 01-16-2013, 03:25 PM
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I never said i could get away with pump gas. Just not having to run raight race fuel all tye time. I already run between 91 and 93 depending on where i stop as well as a 5 gal mixture of 110 leaded at times. I dont think I've ever bought 87 lol. Even then 89 is cheaper where I'm at because of all the corn subsidies. I was only under the assumption that aluminum helps reduce the likelyhood of detonation due to compression because the cool faster than steel.
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  #37 (permalink)  
Old 01-16-2013, 03:53 PM
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I do want to thank everyone for the different array of heads to choose from. I found flow numbers on a lot of them and have more homework to do. The Pro-Filer heads flow very well. Just need to figure out what to spend and which ones my domes will fit in to. I spoke with Federal-Mogal and the said the fit my domes in 58cc chambers. The only thing i need to worry about is if any manufacture changed the location of the chambers slightly. So all should be good! Thanks for all the help!
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  #38 (permalink)  
Old 01-16-2013, 04:17 PM
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Quote:
Originally Posted by Caballerokid View Post
Ok, so I've got a set of virgin 062 vortec heads and have about $600-$1000 worth of machine and port work set to go with Smithburg Racing and I have an opportunity to pick up a set of 186 Fuelie heads supposedly virgin castings for about $400... plus some machine work probably. I've done some digging on flow rates and such... which should I go with? By looking here Stan Weiss' - Cylinder Head Flow Data at 28 Inches of Water -- DFW / FLW Flow Files for use with Engine Simulation Software at the flow rates, the vortecs kill the fuelie heads. Also the I have a set of worked 882s on my engine currently that I am replacing but it shows the 882's don't even flow that bad. I'm now kind of stumped which way I should go with this. Either the vortec head or the fuelie head (64cc chambers) will give me roughly 11.4:1 static CR on my 360 sbc. Any help is appreciated. Thanks
Are you saying you are about to spend $600-$1000 on the Vortec's? If that's the case, don't. Aftermarket aluminum heads are the best choice to make the domes work using pump gas, unless you have E85 available. But even then, I do not trust that E85 will always be available.

Forget the 186 or any other fuelie heads. They will not work w/the compression you're going to have w/those pistons. The only reason the Vortec heads might be made to work is they're not milled and the chambers/ports are a lot better at resisting detonation- providing you keep the quench distance tight.

A couple points:

As you know, don't use a wide quench in an attempt to lower CR. That's just not how it's done, at least unless you're a hack. And you're not. Moving on...

Using less timing than best max power total timing leaves too much on the table. That is not the way to build an engine. Not saying you're even thinking along those lines, but judging by some of the things I'm reading here, it may come up as a "solution". It's NOT. As little as a -4 degree change in timing from best timing can easily cost 50 hp-plus.

Domed pistons are not generally as efficient as a flat top. They are more prone to detonation if anything, not less. If you are bound to keep them, you need a bigger chamber.

Compression w/a 64cc chamber, all else as you are now (0.040" quench, 3.5cc dome, 0.060" over 350) except the chamber size (64cc instead of 76cc) = 11.7:1 (someone needs to check their math). Way too high to even consider pump gas, even w/aluminum heads.

So either you need ~72cc-plus heads (~10.5:1 CR), or lose the domes.

Using an early style intake on an aftermarket Vortec-type head (from Vortec heads):

Quote:
Many aftermarket Vortec style heads (including Bow Tie Vortec heads) feature dual bolt patterns allowing the use of the early 12-bolt intakes. This has a very limited use.

Commonly available 12 bolt SBC dual plane intakes do not have enough metal above the port to be ported to match the Vortec port, w/o having a vacuum leak or razor thin sealing surfaces above the ports. An early intake would need at least 0.325" of material above the intake port opening to have any chance of sealing, and that doesn't take the difference in the port width/location into account. Because of the height of the Vortec intake port, only the single plane 'raised port' race intakes have enough height to actually mate to the Vortec port- but even then the ports may be too wide or have other port fitment issues.

Because of these differences, a Vortec-specific intake should be used.
A heart shaped chamber will require the piston/chamber be mocked up w/clay and the pistons relieved for clearance where needed. This will drop the CR some, but on a 64cc chamber, you have too much CR anyway. Below is a Vortec-specific domed piston for comparison to your piston. As can be seen, there's a fairly large amount of material that needs removing. The plus side is you can rework them to fit the chamber better than the dome used on the Vortec piston, and the reworking will lower the CR. Just not enough, is all.

Vortec dome piston:

Speed Pro ZH618CP60:

There's a chance that by relieving the piston dome to fit the Vortec chamber, along w/stretching the quench distance a few thou, and unshrouding/relieving the chambers using the cylinder bore and a head gasket as a template, that you might be able to get the CR down to a liveable level.

This will also take some fancy footwork when it comes to selecting the cam specs; a narrow LSA, later intake closing point and (slightly) retarded phasing. I would suggest getting w/the manufacturers w/the combo and see what they can do for you.
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  #39 (permalink)  
Old 01-16-2013, 04:32 PM
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So see pic below for pricing and chamber size, and now using your numbers were at 10.5 comp, 0.040 quench, and a head that's inexpensive, and has room to grow if you step up later.

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  #40 (permalink)  
Old 01-16-2013, 04:57 PM
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I chose the domes close to 10 years ago because of the larger chamber heads. Now knowing what i know i wouldn't do it again. That being said this motor has only had a few tanks of gas ran through it. Im not going to tear the whole motor down and start over. Dont have the money and that would take all the fun out of it thats left after a 10 year project with only getting to drive a few tanks through it so far. That being said... if i run a 72cc chamber isnt that defeating the purpose of getting rid of my 882 76cc heads??? I'm still waiting to hear back from Dart if those pistons will be a flat no go or just check them out. As far as feder-mogal who makes the pistons says they should be fine with the 64cc chambers whether we're talking heart shaped or not we'll find out. As far as the compression goes, ya its like 11.67:1 or close to that. I dont care because race fuel is easy to get where im at and wont drive much other than when i want to play with it. So i think im just going to see if i can get them to fit and probably clearance the domes as need be.. A new cam is sooner than later so in the mean time I'm not too worried about that.
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  #41 (permalink)  
Old 01-16-2013, 05:03 PM
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Quote:
Originally Posted by Caballerokid View Post
I chose the domes close to 10 years ago because of the larger chamber heads. Now knowing what i know i wouldn't do it again. That being said this motor has only had a few tanks of gas ran through it. Im not going to tear the whole motor down and start over. Dont have the money and that would take all the fun out of it thats left after a 10 year project with only getting to drive a few tanks through it so far. That being said... if i run a 72cc chamber isnt that defeating the purpose of getting rid of my 882 76cc heads??? I'm still waiting to hear back from Dart if those pistons will be a flat no go or just check them out. As far as feder-mogal who makes the pistons says they should be fine with the 64cc chambers whether we're talking heart shaped or not we'll find out. As far as the compression goes, ya its like 11.67:1 or close to that. I dont care because race fuel is easy to get where im at and wont drive much other than when i want to play with it. So i think im just going to see if i can get them to fit and probably clearance the domes as need be.. A new cam is sooner than later so in the mean time I'm not too worried about that.
There is no comparison between the 882 w/76 cc chambers and a good aftermarket head having 72cc chambers. The aftermarket head will be worth mondo power over the 882's, regardless of the chamber size. Whether the CR will be OK using the 72cc heads remains to be seen.

Use clay to see what the chamber/piston dome fit is. I wouldn't rely on someone telling me- I'd check it myself.

If you don't want to reassemble the engine using compatible parts (you have your reasons, I respect that), leave the 882's on it and drive it. I recall (I think) that it pings w/the 882 head. If that's true, unshroud the chambers and smooth them down to gain a few cc's.
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  #42 (permalink)  
Old 01-16-2013, 05:03 PM
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Quote:
Originally Posted by Caballerokid View Post
I chose the domes close to 10 years ago because of the larger chamber heads. Now knowing what i know i wouldn't do it again. That being said this motor has only had a few tanks of gas ran through it. Im not going to tear the whole motor down and start over. Dont have the money and that would take all the fun out of it thats left after a 10 year project with only getting to drive a few tanks through it so far. That being said... if i run a 72cc chamber isnt that defeating the purpose of getting rid of my 882 76cc heads??? I'm still waiting to hear back from Dart if those pistons will be a flat no go or just check them out. As far as feder-mogal who makes the pistons says they should be fine with the 64cc chambers whether we're talking heart shaped or not we'll find out. As far as the compression goes, ya its like 11.67:1 or close to that. I dont care because race fuel is easy to get where im at and wont drive much other than when i want to play with it. So i think im just going to see if i can get them to fit and probably clearance the domes as need be.. A new cam is sooner than later so in the mean time I'm not too worried about that.
No.....its not the chamber volume that's at question, its the fact that as i have been told a zilliom times, the 882's are the low of the low. The 72cc head means you can run whatever fuel you choose, and I know you said good fuel is readily available,but wouldn't it be nice to not HAVE to run race gas? The profilers, or any other good head that have the 70-72cc chamber fit your build, they flow what you need to utilize your current cam, or almost any other you choose for a street strip motor. And they make it possible to run normal fuel. If you find it snappy and a decent performer now with 882's on it, when you bolt on a "good" head its going to make you grin like an idiot.
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  #43 (permalink)  
Old 01-16-2013, 05:04 PM
How fast is fast enough?
 
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What power level are you chasing after? What RPM window? Odds are you can get the power you want with a lot less compression than you think you need- easier tune, better durability, lower cost to operate, MANY advantages to that.
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  #44 (permalink)  
Old 01-16-2013, 06:49 PM
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I'm just worried that the 72cc chamber won't be as efficient is all. I'm ok with running them if they won't hinder anything. I'm shooting for 400-450hp and 450tq at max rpm 6k. Right now as sad as it sounds, i'm making 250hp and 317tq on a mustang dyno with 34 degrees timing all in by 3k and some detonation with the 882 heads 1.94/1.60 valves and basic performer intake. Peak hp was at 5300 and tq was at 3200. It quit pulling because it couldn't flow anymore air. They heads/cam stalled. Making that much more tq over the hp, it wants to make power but just cant breathe well enough to make more power.
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Old 01-16-2013, 06:58 PM
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Quote:
Originally Posted by Caballerokid View Post
I'm just worried that the 72cc chamber won't be as efficient is all. I'm ok with running them if they won't hinder anything. I'm shooting for 400-450hp and 450tq at max rpm 6k. Right now as sad as it sounds, i'm making 250hp and 317tq on a mustang dyno with 34 degrees timing all in by 3k and some detonation with the 882 heads 1.94/1.60 valves and basic performer intake. Peak hp was at 5300 and tq was at 3200. It quit pulling because it couldn't flow anymore air. They heads/cam stalled. Making that much more tq over the hp, it wants to make power but just cant breathe well enough to make more power.
you can hit 450hp at 6,000 rpm running on 87 octane, the way you're going is about the hardest most costliest way to do it.

Get a set of heads with about a 195-210cc intake runner, a good set with a good chamber. You'll only need about 9.5:1 compression, a plain old RPM intake, a 750 or so carb, good 1 5/8" headers with a good exhaust, and a hydraulic roller cam with about 225/230 duration and all the lift you can find (even a solid flat tappet cam will work if you're pressed for money).

To be honest I'd either consider selling what you have and starting from scratch or at least selling the pistons and swapping in some plain old flat tops.

You can hit your goals with a bone stock junk yard long block if you can find one with flat top pistons.
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