Pro-King SBF setups

General engine tech -- Drag Racing to Circle Track

Moderator: Team

aaron p
New Member
New Member
Posts: 40
Joined: Sat Apr 21, 2007 3:57 pm
Location: Houston

Pro-King SBF setups

Post by aaron p »

Just picked up a set of CFE pro-kings and jesel rockers. Looking to build a engine in the 950-1,000HP range over the next 2-3 years (money wise). Anyone have good experience with these heads? Will be a 2x4500 sheet-metal and all the good parts to go with it. Looking at a Scat CCW crank, GRP rods, wiseco pistons, Dart I/E block, etc..
How much has been made N/A with these heads?
Jason Pettis
Member
Member
Posts: 149
Joined: Thu Jan 24, 2008 12:45 pm
Location: Hesperia, California

Post by Jason Pettis »

We did a 440ci Pro-King engine that made 1035 hp and ran to 9500 RPM. It had a Blue Thunder cast intake with a single 4500 carb and a wet sump oil system, Darin Morgan did the heads and intake and did an awesome job. In a 2750lb car it runs 8.20's 165mph in 1500-2000' air.

One challenge you will face is intake manifold design. With a 9.5" deck and the ports raised as high as they are in those heads, the runner lengths get kind of long. With long runners it will not want to make great power at high RPM, and if you don’t rev it up it will be hard to make great power. You can build an 8.7" deck engine combo for a better intake design but then you are going to limit your cubic inches to a point where your hp/ci will have to be pretty high to achieve 1000hp. If I were to do one today I would probably start with a 9.2" deck block and use around a 4.000 stroke.

It is tough to fit large pushrods in the heads because the intake port size and location interferes with both the intake and exhaust pushrods. Relocating the lifter bores .050 when getting the block bushed helps tremendously here. Use Jesel tie-bar lifters with the 'splayed pair' arrangement so you can have the pushrods offset away from each other. Using a double offset in a conventional link bar lifter is pretty hard on things. Better yet, do a key lifter arrangement if you can swing the cost.

I never understood why those heads don’t seem to be too popular or commonly used. I think the design is pretty good and for us they made a ton of power for a single carb cast intake combo. I bet with a good sheetmetal intake and two carburetors a person could approach 1100hp with a Pro-King engine. Edelbrock has a Pro-King type head called the GV2. I know Kuntz and Co. has done some pretty cool things with the casting but I'm not sure how much power they are making with them.
Pettis Performance Racing Engines
www.pettisperformance.com
RW TECH
Guru
Guru
Posts: 2387
Joined: Thu Nov 24, 2005 9:08 pm
Location: DETROIT, MI

Post by RW TECH »

Kind of unrelated, but the people who did the original design of that head built a 352 CID engine for their oval track car with an 8.200" deck block and a 2961 Edelbrock Yates intake on it.

If I remember this right, the engine made just shy of 800 HP with a 264°/270° cam (under .800" lift) and a standard flange carb on gas.

I know they had ports enlarged later & did a bunch of work to open up the intake manifold but I don't know what the end result was.

Either way it seemed to make a lot of power when directly compared to same CID engines for same application with C3L, C3H, and SC-1 heads on them.
aaron p
New Member
New Member
Posts: 40
Joined: Sat Apr 21, 2007 3:57 pm
Location: Houston

Post by aaron p »

Jason Pettis wrote: Edelbrock has a Pro-King type head called the GV2. I know Kuntz and Co. has done some pretty cool things with the casting but I'm not sure how much power they are making with them.
From what I saw this last weekend from Charlie Booze, they are making 1,000 or close to it. Granted the air at Memphis was like -500' DA also.
9.5" block b/c thats what I have allready on my current engine. What size cam are yall using for that type of setup? Still the 2.18" intake valve? Lowering the peek RPM point wouldnt hurt my feelings any. Lower RPM usually means increased longevity to a point. Was that a 2.00" rod pin on that engine. Very killer power for a cast single carb engine and wet-sump! I was worried that id have to go dry-sump. I do have a Peterson Wet-vac on my current engine that id like to use on the Pro-king engine if possible.
Speed Doctor Racing Components
Custom machined parts to your specs, lightweight billet 5/8" 12pt lug nuts!
mrgofast27@aol.com
aaron p
New Member
New Member
Posts: 40
Joined: Sat Apr 21, 2007 3:57 pm
Location: Houston

Post by aaron p »

Apparently somebody called the guy with these heads just a few minutes before I did and is sending money for them. Man, major opportunity missed once again! Only wants $2900 for them brand new with Victory valves and Nextek springs. :( :cry:
Speed Doctor Racing Components
Custom machined parts to your specs, lightweight billet 5/8" 12pt lug nuts!
mrgofast27@aol.com
Jason Pettis
Member
Member
Posts: 149
Joined: Thu Jan 24, 2008 12:45 pm
Location: Hesperia, California

Post by Jason Pettis »

The crank was a 1.888 rod journal with a 2.750 main. We used a 55mm cam but I think I would go with a 60mm if I were to do one today, I might even consider a smaller main journal but with a 4.000 stroke I'm not sure about that. The cam was in the 280's intake and 300's exhaust with a .525ish lobe. 2.220 intake and 1.600 exhaust valves. I have not used the Peterson wet-vac deal but I will say that this particular engine liked 17-18" of vacuum. Not sure if that wet-vac combo will pull that much, I know a Moroso or Star pump will get you close to 20" if everything is right.

Bummer about your deal falling out, maybe next time eh?
Pettis Performance Racing Engines
www.pettisperformance.com
aaron p
New Member
New Member
Posts: 40
Joined: Sat Apr 21, 2007 3:57 pm
Location: Houston

Post by aaron p »

Bummer is a understatement. We will see if I have any luck at all come thursday if the guys cash dont show up.
Speed Doctor Racing Components
Custom machined parts to your specs, lightweight billet 5/8" 12pt lug nuts!
mrgofast27@aol.com
aaron p
New Member
New Member
Posts: 40
Joined: Sat Apr 21, 2007 3:57 pm
Location: Houston

Post by aaron p »

Well, there is a god after all! :)
A guy that knows you quite well Jason has a brand new set of Pro-Kings that he is gonna let me have at a very good deal. I was curious as I was looking close at the pictures he sent me, is that raw casting spot normal by the bowl area on the intake port? He also mentioned that the heads go about 405cfm on his bench. Name is Kirk. 287cc intake port. They do look like some bitchin heads. Ill probably buy them by the end of this week. Gonna have to get valves, springs, and hardware to go with them. I was curious, do you have a ARP part number for the head studs?
Speed Doctor Racing Components
Custom machined parts to your specs, lightweight billet 5/8" 12pt lug nuts!
mrgofast27@aol.com
aaron p
New Member
New Member
Posts: 40
Joined: Sat Apr 21, 2007 3:57 pm
Location: Houston

Post by aaron p »

Heres a shot of the casting area in the intake port that didnt clean up.
Image
Dosent look that bad to me. 444cid is sounding good. 4.100x4.155
Speed Doctor Racing Components
Custom machined parts to your specs, lightweight billet 5/8" 12pt lug nuts!
mrgofast27@aol.com
Jason Pettis
Member
Member
Posts: 149
Joined: Thu Jan 24, 2008 12:45 pm
Location: Hesperia, California

Post by Jason Pettis »

Glad to hear you found some heads. We used ARP 254-4314 head studs. The outside row will probably hit the exhaust port/header adapters if I remember correctly. Test fit those items so you can shorten the studs if needed before you get it all together for real. The spots on the castings that didn't clean doesn't look too bad but you might want to fill/smooth it with some epoxy. There are several to choose from but Z-Spar is pretty good and easy to work with. Stuff like that sometimes will not affect the flow bench numbers but it wouldn't surprise me if it affected the fuel/wet flow.
Pettis Performance Racing Engines
www.pettisperformance.com
aaron p
New Member
New Member
Posts: 40
Joined: Sat Apr 21, 2007 3:57 pm
Location: Houston

Post by aaron p »

I thought it might be that same part number since th N351 head is also a 10deg deal. Thanks for the info Jason, I appreciate it!
Speed Doctor Racing Components
Custom machined parts to your specs, lightweight billet 5/8" 12pt lug nuts!
mrgofast27@aol.com
aaron p
New Member
New Member
Posts: 40
Joined: Sat Apr 21, 2007 3:57 pm
Location: Houston

Post by aaron p »

Jason, Did yall find anyone who makes exhaust port plates or header flanges for these? Did yall see any improvements using a port plate say 3/8" thick or so, then go to the header/flange? I measured the exhaust port and its only about 1.625" oval at the flange. Not very big. I can design my own very easily, just wanted to see if somebody has allready made them? Maybe ill market them if nobody else has?
Speed Doctor Racing Components
Custom machined parts to your specs, lightweight billet 5/8" 12pt lug nuts!
mrgofast27@aol.com
aaron p
New Member
New Member
Posts: 40
Joined: Sat Apr 21, 2007 3:57 pm
Location: Houston

Post by aaron p »

Just drew these up on CAD. They are the exact dimensions I got off the machined surfaces on the head. A 2" header would be huge on that port it seems like.
Image
Speed Doctor Racing Components
Custom machined parts to your specs, lightweight billet 5/8" 12pt lug nuts!
mrgofast27@aol.com
Jason Pettis
Member
Member
Posts: 149
Joined: Thu Jan 24, 2008 12:45 pm
Location: Hesperia, California

Post by Jason Pettis »

We did not use any header adapters, all the headers we tried had a flange on them that fit the heads. However I'm not sure that was the best idea. I think a properly fitting flange adapter that extended the runner would pick up a bit of power. I don't remember what size headers worked best and I'm not at the shop to look it up but I want to say they were 2" or even maybe 2-1/8".
Pettis Performance Racing Engines
www.pettisperformance.com
aaron p
New Member
New Member
Posts: 40
Joined: Sat Apr 21, 2007 3:57 pm
Location: Houston

Post by aaron p »

ok, thanks for the info.
Speed Doctor Racing Components
Custom machined parts to your specs, lightweight billet 5/8" 12pt lug nuts!
mrgofast27@aol.com
Post Reply