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I am finally ready to assemble my 383. I thought that I had purchased pro topline cylinder heads but it turns out that they are a company called ProComp out of Australia. Nice looking heads. I was wondering if anybody has used these before? Do they require a raised runner intake? Cant wait to get the engine together, I think itll make some good mid torque and over 400hp. We'll see.:D
 

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scottyz said:
I am finally ready to assemble my 383. I thought that I had purchased pro topline cylinder heads but it turns out that they are a company called ProComp out of Australia. Nice looking heads. I was wondering if anybody has used these before? Do they require a raised runner intake? Cant wait to get the engine together, I think itll make some good mid torque and over 400hp. We'll see.:D
Do you have any flow numbers, cam specs, etc?

You should be easily over 400 if your cam, heads, and intake match. I'm over 400 with mine and I have a relatively small cam. Which rods are you running?
How much compression? Do you know the dome volume (dish, reliefs, dome), head cc, piston to deck clearance, gasket cc (or bore and thickness)? This will all help. I run 210-220 cranking psi on 93 oct pump gas, but on 91 clean-air swill I need to add some booster. On these engines, a little compression goes a long way. btw, I shift at 5,600rpm.
 

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I did see some numbers somewhere. I will have to look further. As for the specs. It uses an eagle SIR rod, 5.7 inch with a KB piston with advertised 18cc dish. I just got the block back from getting decked to bring the piston to zero deck height. I wanted that quench and to bring the compression up a bit. It will be around 9.65-1 comp ratio with a .041 head gasket. The cam is a comp XE274 hydrualic flat tappet. It has 230-236 int/ex @ .050 and .490/.496 lift. Nothing huge and split pattern because when I did see the flow numbers on the heads the exhaust side was a bit weak. The exhaust to intake percentage was in the low to mid 70s and I think at .600 lift it was like 68% but I wont see that lift so it doesnt matter. CLean heads though. Room for porting too but I wont do it right now. As for the intake --- I was going to use a Weiand Stealth manifold but another person on another board said that these heads are raised runner so I wont be able to use this intake. I havent had time to look yet. If that is the case then I will have a RPM air gap vortec modified to fit. THe car is around 3600 pounds with a 2600 stall converter and a 3.73 posi. Mallory ignition and holley 750 vac secondary for now. I went fairly mild I figure as I was looking to be able to drive it whenever I want. What are your specs nailhead425
 

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scottyz said:
I am finally ready to assemble my 383. I thought that I had purchased pro topline cylinder heads but it turns out that they are a company called ProComp out of Australia. Nice looking heads. I was wondering if anybody has used these before? Do they require a raised runner intake? Cant wait to get the engine together, I think itll make some good mid torque and over 400hp. We'll see.:D
I'm in the same place you were.Me to building a 383 with the Procomp heads. They have raised intake runners, does anyone know what intake would work with theses heads? Thanks!
 

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I can't begin to tell you all the problems these heads have!! I will tell you this, I just finished dyno testing a 383 with them, and could not make over 368hp with an as cast set of 195s... I put on a set of cast iron vortec heads (out of the junk pile) w/stamped steel rockers and incorrect push rod lenght, and made 30hp and 31lb ft.tq more. That should say enough about those POS heads, but if you still do not believe, they sent me 2 sets of CNC'd heads (195-210) they CC'd at (195=216cc/210=213CC) and they are so bad, I wont even take the chance of putting them on the engine!!!!
P.S. when they CNC'd them (or what ever you call it that they did) they cut the seat's right out at the spark plug side (note: spark plug is located .500" to low)!!
I have the dyno sheets if any one would like to see!
P.S.S. Brodix IK 180 test coming 11/02/07

See Here:http://www.boatstoreonline.com/procomp.html
 

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I have used these heads on several engines and my dynojet numbers were much like a previous poster..

On a 383 GM and a 347 Ford it was difficult to exceed 400 HP. But all made very VERY good torque.

I have to agree these are not the best heads to hit the market.
They are however, super affordable..

I am in the automotive machine business , complete heads with roller springs and 2.05" intake and 1.60" exhaust valves are around $800.00...

The biggest flow problem I have with these heads is that they use a cutter before the seats are installed and just plunge it down into the bowl leaving a huge ridge.. Making porting them a new adventure.

If you are handy at all, a few hours on these heads really opens them up..
It does take some handywork to get any sort of a match on the intake ports..

I just built a 383 GM ..
Using a pair of hand ported ProComp heads.
An ******Comp cam.
A modifide RPM Vortec intake..
Flat top pistons.. < some pinging issues, that a more aggresive cam will hopefully overcome>
Not unusual with some Comp cams with the fast closing intake lobes..

Balanced, blueprinted. line honed and decked .005 only to equalize the deck height..

Made over 430 Hp on the dynojet.. It has enough torque to pull a bridge off it's foundation. I don't think this is shabby for a budget street motor.

Take it for what it is worth,,
 

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I've heard both good and bad about these heads, I guess it's just hit and miss. However I have heard repeatedly that out of the box they are crap and need machine work to get to where other heads are out of the box.

So I guess it depends on where you decide to have your machine work done, how much it will cost you in order to see if they are really a bargain.
 

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I am finally ready to assemble my 383. I thought that I had purchased pro topline cylinder heads but it turns out that they are a company called ProComp out of Australia. Nice looking heads. I was wondering if anybody has used these before? Do they require a raised runner intake? Cant wait to get the engine together, I think itll make some good mid torque and over 400hp. We'll see.:D
:drive: HEY Re PROCOMP HEADS - you might want to check out Oct '09 Super
Chevy edition for the article "CHUMP CHANGE CHALLENGE" in which they use
a set of PROCOMP 109cc/70cc 2.02/1.60 single plane heads obtained on
eBay to build a 400+ HP & lb-ft. cheap build engine. Good luck with it.
 

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I am finally ready to assemble my 383. I thought that I had purchased pro topline cylinder heads but it turns out that they are a company called ProComp out of Australia. Nice looking heads. I was wondering if anybody has used these before? Do they require a raised runner intake? Cant wait to get the engine together, I think itll make some good mid torque and over 400hp. We'll see.:D
Procomp are cheap. I cannot say anything else that is good about them.

Red Hot Mike
 

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I built a 383 wit procomp heads. I used same intake as came originally on the GM Performace Parts crate engine. Edelbrock Performer intake I think. It was several years ago. I thought the company was ProComp Electronics if my memory serves me right...I ordered them from Jegs. They have a forum on their website. Just go on there and ask them. Tell them the heads came from them.
 

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gotta ? i have a set procomp heads on a 67 327sbc. it has a voodo cam 489/504 and aluminum prw roller rockers. the motor is together and running but the underside of the rocker is tapping on the top of the valve spring. it has 202/160 valves with a 1.46 spring diameter. what can i do to correct this.. i got longer push rods and that didnt help at all......any suggestions
 
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