P-51s came yesterday

Fed-Ex stopped at my house with my P-51s yesterday (Saturday). I got a call on Thursday afternoon from Kaase's shop and they put the heads together that afternoon and shipped them on Friday. All I can say is WOW ... Now to get them to my engine builder on Monday.

Congrats! So now then, what's the application for?

Charlie

They're going on my 533 I'm having built for the P.O.S. pullin' truck. RPM Machine in Lehighton, Pa. is building it. Now I have to order the "Mafia Intake". I'm looking for around 850 hp.

So if it's a pulling truck application, then it's safe to assume you got some titanium retainers and "big" valve springs with those assembled heads. Correct?

Charlie

They came set up for .800 lift solid roller. I believe they're steel retainers. Not going to turn over 7,200 rpm.

Nice heads, if you don't mind what's the rest of your build consist of? Also, unless you're gonna run a huge tire, 24:1 or higher final, or pull an 8000lb class an 850hp 533 is gonna want to spin well past 7200. Hopefully you don't plan on letting it sit on the rev limiter? I have a 521 p51 heads and I'm well under 800hp, 24.5:1 final with a 33" tire and mine goes 7600 - 7800 on most tracks, 8200+ on a loose track but I pedal it to keep it under 8k. I'm just running a 4150 style carb too, I'd imagine it would spin harder with a dom. carb. I'm guessing it doesn't peak past 6500 rpm so I try to gear it to run around 7500, but you know how much tracks vary. Good luck and have fun

posford wrote:They came set up for .800 lift solid roller. I believe they're steel retainers. Not going to turn over 7,200 rpm.

Please don't take this wrong, I am trying to help you out here. But the "I believe" part scares me. You should know whether or not you paid for steel retainers or titanium retainers. There's about a $250 difference in price.

Most likely your valvetrain mass will not let the engine rev to 7,200 rpm, IF they are steel retainers. We are talking truck pulling here, and you're at WOT for about 18 seconds. Your engine builder should have already given you this advice, if not, find another engine builder. Meanwhile, check them with a magnet and be sure. If they are steel, plan on swapping them out for titanium retainers immediately.

Charlie

c.evans wrote:

posford wrote:They came set up for .800 lift solid roller. I believe they're steel retainers. Not going to turn over 7,200 rpm.

Please don't take this wrong, I am trying to help you out here. But the "I believe" part scares me. You should know whether or not you paid for steel retainers or titanium retainers. There's about a $250 difference in price.

Most likely your valvetrain mass will not let the engine rev to 7,200 rpm, IF they are steel retainers. We are talking truck pulling here, and you're at WOT for about 18 seconds. Your engine builder should have already given you this advice, if not, find another engine builder. Meanwhile, check them with a magnet and be sure. If they are steel, plan on swapping them out for titanium retainers immediately.

Charlie

^^What he said! I spin my little iron headed 466 to 72-7400 and I am glad that Lem and Dave had me go with the titanium retainers. Knowing now what I didn't know then, I was looking at the money involved, and not the longevity and strength needed. I learned and am much happier for it.

They are definitely steel retainers ( I was really tired when I posted yesterday and wasn't thinking clearly). The standard Kaase .880 lift solid roller package package. I'm going up to the builder's today. He's built plenty of BBFs for folks in this area. I've talked with several of his customers ( one of them runs a sand rail w/a 600 inch BBF with nitrous ) and they are all happy with his work and I'll discuss this point with him. I'll give Kaase a call and see if I can swap out the retainers. I'm not quite sure of the piston configuration yet. I'm looking for around 14-14.5 compression and am thinking I'll need about a 12cc dome to achieve that and will probably have to have custom pistons. Either that or cut the heads a little. It's gonna be a 4.3 stroke, 4.44 bore dove-a 4 bolt block, custom solid roller cam, "Mafia" intake, and for now a 1050 Dominator. I know the carb is a bit small but will have to do for now. Hopefully it will be done before the end of the pulling season so I can get a few runs on it. The builder has a dyno and I'm gonna spend the extra bucks to have it dyno'd and get my initial tune set and see where I stand. The .030 over block sonic'd good with .200 on the thrust sides, so we're going .080 over to leave room for future clean up. It's also filled to the w/pump holes. I still have to figure out the final ratio for the truck, right now I have 33' tires but I plan on running 35" boggers which seem to work well on the tracks in my area. I have a lot of work ahead of me getting the whole truck set up.

Get the titanium retainers for sure! And you might want to look at titanium intake valves.

HorsinAround wrote:Get the titanium retainers for sure! And you might want to look at titanium intake valves.

and on and on, LOL

As stated the titanium retainers for sure. Titanium valves are nice and will extend the life of your valve springs so over time can pay back some of the initial cost.

Another option that gets you about 1/2 way between the weight of the std. valve and Ti is a hollow stem SS valve. If you do keep that 7,200 RPM limit it can be a nice option.

Thanks for all the replies. I'm gonna swap out the steel retainers for the titanium ones.

Are you using a stock block BTW. With14-1.and Nos?

2fox wrote:Are you using a stock block BTW. With14-1.and Nos?

Who said anything about nos?

DOVE-A 4 bolt block filled to water pump holes NO nitrous. Decided to go with flat top pistons, around 13.4 to 1.