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p51 or boss 9?

10K views 14 replies 9 participants last post by  hotrod429hemi 
#1 ·
Im looking into putting either the boss 9 crate or the p51 crate into my 99 mustang. im looking to get around 850hp on racing fuel. The p51 crate is advertised for over 800 hp, and is less than 15,000$. The boss 9 crate doesn't advertise too much, but it is around 17 or 18,000$...
I do not want a turbo or blower. what would be the better option for a strict drag car?

-brandon
 
#2 ·
BUILD A BOSS 429, YOU WONT BE SORRY
 
#3 ·
Brandon,

I won't say as to which would be the better option,,,,,however I will say that the P-51 heads are not a bad choice, in fact they are a very good choice.

For example the P-51 headed engine of Bobby Shrewsberry's, won Super Pro at the Ford Bash this year. His 559 CID engine dynoed 942 Hp on a very accurate DTS dyno on gasoline with a single Victor intake manifold and a Phillip Oakley tuned Quick Fuel 1250 cfm QFX carb. It also made 777 lbs.ft. of torque from 5600 through 6200 rpm, with a very broad torque curve.

Likewise Randy Moore, who won Super Pro at the 2008 Ford Bash, has a 562 CID P-51 headed engine. It made 951 Hp with the new TFS single plane intake manifold and again a Phillip Oakley tuned Quick Fuel 1250 cfm QFX carb on gasoline. It was dynoed on the same DTS dyno.

Food for thought?
 
#4 ·
As far as food for thoughts go, that's one big slice of cake right there! And it's all good!
 
#6 ·
521ci is plenty big enough for me

i was thinking about p51 in the beginning, but then i messaged kaase and cliff messaged back saying he recommended the boss 9, but didn't get to in depth why, and i've sent a couple messages back and haven't gotten a reply in quite some time (no offense to the kaase team, i get that you guys are busy). But the p51 521cid crate on racing fuel should spike up the hp to 850 for only 14k or 15k. So why get the boss 9 crate?

But im still not set...soo

BOSS 9 OR P51 CRATE?

-Brandon
 
#8 ·
Brandon,

The Boss 9 is the better head and you will get the "WOW" factor!
The P-51 WILL get you to your target HP for a little less money. If Kaase is building this motor for you, I would do whatever Cliff advises; he is a very smart guy:)

Bruce
 
#11 ·
Brandon,

There are a lot of very good engine builders on this site; pick one and then work with "that" builder on your motor.

The "best" head depends on lots of factors that your builder can explain to you.

Good luck with your build.

Bruce
 
#15 ·
Trying to decide which headed engine to go with

It looks like you have already found out what I was going to say. I spoke with Jon two years ago at the Performance Racing Industry Trade Show and he said a good 13 to 1 521 with decent heads would make 800 plus horsepower and the Boss 9 heads would make 900 plus. So, there is your answer. A couple of grand extra for 100 or so more HP. What a deal. Let the Nascar guys find an extra 100 HP for a few grand and all heck will break out and there will be a Stampede. Mike@ Performance Modifications.
 
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