Help Me Pick New Heads for 383 Please

[Spot1984]

Well I got a 383...Here is the specs:

Crank- 4340 Forged Steel Crank
Rods- H Beam 4340 Rods 6.00 inch
Pistons- Keith Black Icon Forged Pistons Flat Top with Two Valve Reliefs(+4.90cc Head volume) 4.030 Bore
Cam- Comp Xtreme Energy Hydraullic Roller( Intake @ .050 248/Exhaust @ .050 254) Intake lift .562/Exhaust lift .580, Lobe seperation 110
Heads- Be nice, I got WAY cheap on heads (ran out of money) Aluminum ProComp 64cc Combustion Chambers, 210 cc Runners/ 2.02 Intake, 1.6 exhaust
Rockers-Roller Shaft mounted Rocker System by RPM 1.5 Ratio
Valve Springs- Isky(Dual Spring) 275 lbs/inch
Carb-Holley 750 Street HP

Not Sure what this set up will make but I know the heads gotta go! I haven't ran the motor yet but now I have some dough ray ME that the old lady doesn't know about sooooo.....lol! I'm sure you fellas can relate. Which heads would you suggest? Thanks Guys!

[GMR-PERFORMANCE]

I have not run those heads, but there a few that will run it throught a desk top dyno program.. super 73 would be one to get in touch with.

If you bought the heads use them. A 383 like that ( close to my old one) will be a soild street engine. what intake do you have??

A 383 with the right compression for the cam you have should make great TQ,.. But my own 383 with a tad bigger cam and a single plane intake made just under 540 at the crank, tq was in the 480 range.

Maybe have the heads CNC cut ?? I am thinking about it for my own 220 RHS going to have them worked to the new CNC 228 set up. Cost is about 500-600.. something to think about. But if you have not run the set up you might be very suprised at how well it really works. Again use of the engine, for the street a engine that has a great tq curve is way more fun than a high RPM hp engine.

[Spot1984]

The Intake manifold is a Hurricane Single plane. 3,000-7500 RPM

[GMR-PERFORMANCE]

I ran that same unit on my old 383, I had 10.5 comp and a flat tappet cam.. Just a bit bigger. Head flow is one thing but how it works as a kit is another.. Myself would say have the engine dynoed and then make the choice. Like I siad for the street a engine that makes big tq right out the hole is a ton of fun.. Hp motors need a manual trans and good gears or a auto will need good gears and a loose convertor to have a nice feel. If a engine does not really come on until 3500+ hwy gears are going to leave you feeling like the engine is a dog for normal use..

Street strip is a always a give and take deal.. If the truck is a 80% street deal then build it for that. Gearing will really help make a engine snappy if the set up is a bit sluggish down low. But the hwy deal comes into play at that point unless you have a OD trans

[Boostedbowtie]

I like the AFR195 street heads .

[Lower]

Use what you got, just gasket match the heads and intake and run it. Those heads should flow just fine with what you got. If you were going to run nitrous or forced induction you might want bigger but those should do ok.

[Spot1984]

Thats just it...I'm gonna a run at least a 150 shot of NOS

[Captainfab]

A 383 with flat tops and 64cc chambers, your static compression will probably be in the 11-1 range. Too much for pump gas. However you might calculate just what your dynamic compression will be with that cam. But then again, you didn't say if this a track only engine, or if it is street/strip.

[Spot1984]

I would like to street/strip and if possible run pump fuel on the street

[GMR-PERFORMANCE]

I would say that you do not have too much for pump gas,.. static does not mean anything at all until the cam is factored into the formula. I am running 11.1 with the Howard's cam that is so close to the comp 294 ( one step under this cam a 300) That cam is going to hemorrhage CCP at low & mid RPM levels. I don't know where the idea came about that you cannot run higher compression on the pump gas. We build air cooled HD engines and run them well above that.. It is all based on the cam timing.. Look at the dynamic compression not the static.

I have 11.3 in my 900 lbs touring bike it runs on 91 octane fuel in 110+ temps here in AZ.

I don't have the intake close point at 50 for that cam but based on my own cam and 11.1 comp ( mine closes before that 300 does) my dynamic is 8.8.1 that WILL run on 91 octane fuel. If you cannot tune a engine well thats another story no blame on the set up though.

His will be at the " so called" 8.5.1 or under level. No idea where that 8.5.1 limit came from for pump gas.. but that must be for the no talent tune deal.

I get a bit testy when it comes to compression and set ups. There is no set in stone number. Static is just that a simple formula for cylinder volume. Add the cam and then you have something as a base line. Even that is only a base line type figure, as there is a ton more going on with a cam lobe then a few figures that get published. We own several custom cam grinds that I designed. And after you see what is really going on with a cam and how it works its a real eye opener..


Update I played around with another of my programs. here is his set up with that cam.. It was lower than I had thought.. In fact he could bump the comp ratio a bit and still get by on 91 pump gas at his level his is all in the safe zone.. : ) I ran it for 0 feet if you have another target for elevation let me know , but it will only lower the number.

Static compression ratio of 11.1:1.
Effective stroke is 2.61 inches.
dynamic compression ratio is 8.03:1 .
dynamic cranking pressure is 159.75 PSI.
dynamic boost compression ratio, reflecting static c.r., cam timing, altitude, and boost of 0 PSI is 8.03 :1.
V/P (Volume to Pressure Index) is 128

[BigDan3131]

If you suspect the heads having any issues take them to your engine builder and have them torn down and inspected for proper fitment of everything. 200cc heads are the limit for a 700hp blown 383 so you should be fine.

[Captainfab]

Steve. If you will take a look, I did recommend that he calculate the dynamic compression.

Originally Posted by GMR-PERFORMANCE

I would say that you do not have too much for pump gas,.. static does not mean anything at all until the cam is factored into the formula. I am running 11.1 with the Howard's cam that is so close to the comp 294 ( one step under this cam a 300) That cam is going to hemorrhage CCP at low & mid RPM levels. I don't know where the idea came about that you cannot run higher compression on the pump gas. We build air cooled HD engines and run them well above that.. It is all based on the cam timing.. Look at the dynamic compression not the static.

I have 11.3 in my 900 lbs touring bike it runs on 91 octane fuel in 110+ temps here in AZ.

I don't have the intake close point at 50 for that cam but based on my own cam and 11.1 comp ( mine closes before that 300 does) my dynamic is 8.8.1 that WILL run on 91 octane fuel. If you cannot tune a engine well thats another story no blame on the set up though.

His will be at the " so called" 8.5.1 or under level. No idea where that 8.5.1 limit came from for pump gas.. but that must be for the no talent tune deal.

I get a bit testy when it comes to compression and set ups. There is no set in stone number. Static is just that a simple formula for cylinder volume. Add the cam and then you have something as a base line. Even that is only a base line type figure, as there is a ton more going on with a cam lobe then a few figures that get published. We own several custom cam grinds that I designed. And after you see what is really going on with a cam and how it works its a real eye opener..


Update I played around with another of my programs. here is his set up with that cam.. It was lower than I had thought.. In fact he could bump the comp ratio a bit and still get by on 91 pump gas at his level his is all in the safe zone.. : ) I ran it for 0 feet if you have another target for elevation let me know , but it will only lower the number.

Static compression ratio of 11.1:1.
Effective stroke is 2.61 inches.
dynamic compression ratio is 8.03:1 .
dynamic cranking pressure is 159.75 PSI.
dynamic boost compression ratio, reflecting static c.r., cam timing, altitude, and boost of 0 PSI is 8.03 :1.
V/P (Volume to Pressure Index) is 128

Originally Posted by Captainfab

A 383 with flat tops and 64cc chambers, your static compression will probably be in the 11-1 range. Too much for pump gas. However you might calculate just what your dynamic compression will be with that cam. But then again, you didn't say if this a track only engine, or if it is street/strip.

[GMR-PERFORMANCE]

LOL well what can i say but sorry missed that line.. At least I did the math for him ..

[Spot1984]

Awesome I just found out what dynamic compression ratio is about 20 minutes ago..Only heard of static. I ran it on a calculator and came up with the same numbers. Man this is some fun stuff! So I should be able to get by with 91 on the street then! Thanks fellas. I'm not having a problem with my heads only that I will be dumpin a 150 shot of NOS in it and what to make sure the heads I have can handle that extra flow. O and I don't have an engine builder. I'm learnin as I go here. I have built quite a few stock jobbers but this higher performance is new to me. My theory is what one man can do another can do...that is why I ask A LOT of questions lol. Thanks fellas!

[SeventyOne]

I hear a lot of you guys saying the procomp heads will do fine - I have also heard a lot of people say these heads are garbage in other contexts.

I know it's all about the flow and lift numbers rather than a name (Procomp vs AFR for example) but will these heads really stand up to what he wants to do?

[Spot1984]

Precisely Seventy One! That is the question at hand.

[johnsrob]

Spot1984 I feel your pain, been where you are many times and alot of restless nights lol.

I have bought two pairs of AFR personally I vote for the AFR. Both were competition package eliminator 195 and 210. I live here in the bay area its a guy on craigslist pretty cool dude selling his brand new never mounted AFR eliminator 195 #1040 street heads. I was going to buy them just to have on hand, but my project came screaming at me WTF WTF WTF CHUCK. lol lol My buddy has the pro comp 210 decent pair heads claims to flow 270cfm at 500, 600, lift at .050 has a mutha thumper cam spins the tires without even trying. I would personally spend the money for AFR 220 expensive but it give you alot of room to grow and the combo's are endless.

[GMR-PERFORMANCE]

Well lets say that the cheaper heads you look at flow "X" and the high price heads flow "X" end of the day You may find that just because the other head out flows another set it may really not end up giving you any more power that is worth the extra money at the end of the day. Lets say you spend an extra 500-600 for the better heads and it gives you +10 on the big end.. Many times yes there are better items but the question is do you NEED it.. ??

Nothing wrong with a engine the produces great usable TQ vs the peak hp dyno sheet ..

[SeventyOne]

Originally Posted by GMR-PERFORMANCE

Well lets say that the cheaper heads you look at flow "X" and the high price heads flow "X" end of the day You may find that just because the other head out flows another set it may really not end up giving you any more power that is worth the extra money at the end of the day. Lets say you spend an extra 500-600 for the better heads and it gives you +10 on the big end.. Many times yes there are better items but the question is do you NEED it.. ??

Nothing wrong with a engine the produces great usable TQ vs the peak hp dyno sheet ..

Good point on the flow numbers. I myself have the Procomp 190cc heads on my 383. I've yet to fire it up though...and that's why I have an interest in this thread.

I've been in the same place as the original poster though - thinking I should upgrade the heads but then again I may be perfectly happy with the way the engine performs w/o spending another grand.

IF I was going to upgrade though I like what I see out of the Patriot Performance heads.

[GMR-PERFORMANCE]

I looked very hard at a set of patriot when I was building my LS for the sand rail.. I decided that I would spend my money else where. My very basic LS6 ( one of the several ls engines I had) with a truck intake and a small comp cam put down to the rollers 480 Hp and 466 tq.. Through a Albines 5 speed transaxle, 934 CV's and 35 inch goodyear MTR's in the sand it was a TQ monster.

Here is what TQ can do power wheelies up the hill down the hill any where any time you want it. Stomp the pedal no clutch needed . And before any one says well the engine is in the back.. Thats a 3200 lb car ( it was weighed on a CAT scale) it is a lot harder than you think. I lost hp with the truck intake but gained a huge chunk of tq in the mid section. Right where its needed..

[Boostedbowtie]

Originally Posted by johnsrob

a guy on craigslist pretty cool dude selling his brand new never mounted AFR eliminator 195 #1040 street heads. .

I'm using them on my 9:1 383 with 21psi of boost making a little over 1000 to the wheels . 75cc combustion chambers .

I've had these heads for many years on my motor , everything from N2O , then a Procharger , now a turbo .

Several engine rebuilds , but one set of heads ...........IMO heads are an investment .

FYI , I bought them back when they were the old design . Then 2 years later during a rebuild , we found cracks in the combustion chamber from a casting flaw . Even after 2 years , AFR sent me brand new heads ( new design )complete with my choice of springs .

[johnsrob]

I really do see your point "GMR" and well put. The heads I recommended from AFR was 220 eliminators. Let's not just look at HP, consider the torque also and I agree with you. I think these heads are a happy medium, I feel you are killing "THREE BIRDS" with one stone.

1. Your HP and Torque Gain should have a significant improvement more 10 I imagine

2. It will quench your thirst for right now and accomadate what you are building now

3. We always want more HP and TQ after a certain period of time it is the nature of the beast and comes with terriority. You give yourself an opportunity to go to the next level if you want and not plateau. In other words you are getting your money worth maybe you want to build a 406, 434, and so on or use more aggressive cams. Think of it as having kids. Your son is a growing boy you wouldn't buy him clothes or shoes that are a perfect fit you will probally by them a little big so he have them for awhile and grow with him.

On the patriots heads, have a buddy that bought a pair also,made awesome power with one of those LUNATI VODOO cam. not sure of the runners though. good heads though

Have any of you guys heard of DR. J's perforamance and their Air Wolf CNC Ported Cylinder Heads

http://www.j-performance.com/index.p...d=44&Itemid=60