Skip to main content
Topic: Man-O-War vs BOSS vs stock 5.0 block (Read 3102 times) previous topic - next topic

Man-O-War vs BOSS vs stock 5.0 block

I have finally decided to go all out and finish my T-Bird as a bullet proof weekend bracket machine. With additions of fiberglass front-end, trunk lid, doors and typical interior gutting I should get the car down to a respectable 26-2800 lb curb weight. I was trying to decide should I go with a stock 5.0 block and build a 331, 347 or just go all out and use a Boss or World Products Block and build a 340 or 370 ci 8.2 block while still retaining my GT-40 P heads. I do not see any benefit in increasing the cubic inches with these heads beyond 331. To build a bullet proof weekend racer that all I do is add gas and change the oil, a low RPM larger cubic engine is very intriguing. This would keep the repair and maintenance costs down but would it actually off-set the costs of building an aftermarket block motor? Any feedback would be appreciated if it is reasonable.

Man-O-War vs BOSS vs stock 5.0 block

Reply #1
The boss and manowar blocks are good but why spend the money and cheap out on the heads. Not knocking the “p”s there good heads but for the money you’re spending on the block why not go w/a good aluminum head. Or just stay w/ the stock block experts say it can hold 500hp.if your building for a class that requires ford heads (ex. GT40P) stay w/the stock block and build it right.


My 2 cent go w/a 351 block it’s built almost as strong as a boss block and free displacement.

Man-O-War vs BOSS vs stock 5.0 block

Reply #2
Last thing I'd do is get a stout aftermarket block then, choke it with "Ps"... The aluminum heads are light years better and knock off 45 lbs to boot... The Man-O-War blocks are heavier due to more meat in the block, you'll need the aluminum heads to keep weight approx the same...

If I had a few bux(OK a lot of $$$) I didn't know what to do with, I'd just buy a complete 372cu in...

Man-O-War vs BOSS vs stock 5.0 block

Reply #3
IMO.  Keeping the 'P' head with an increase in displacement is waste.  Why spend the money on stout short block just to choke w/heads which are just adaquate on a 302. 

Sounds like you are putting together a good chassis and getting the car light.  Money well spent to get the most of your combination.

If your interested in an education on how to build the engine, go to SBFTECH.com.  The Myths section is particulaly enlightening.  It may help you from going down the wrong path on your build.

Man-O-War vs BOSS vs stock 5.0 block

Reply #4
These were my thoughts exactly! The GT-40P heads are perfect for a street/strip 302 in a stock car. I liked the idea of having a 370 ci small block but I need ARF 225 heads or the AFD Clevor heads just to feed it and the costs just start getting outta hand. I already have quite a bit of 302 stuff, so it would be cost effective to stay with a 8.2 inch deck height block. That would mean that a 351 is outta the question.

Thanks that confirms my thoughts, a 331 based on a stock 302 block would be the best. Upgrading the heads later would be the best since I have a long way to go to get the bird back on the track. My GT40P heads were ported and polished by Panhandle Performance in FL when I lived in MS, so they flow quite well for some "stockers" and would work well on a 331.

There is no more nitrous in my future since it was just to expensive. I lost two rearends, 3 trannys, and 1  block to the NO2 and I intend to never screw with the stuff again. The car was fast and fun, its just a parasite on the wallet and I wanted to finish it once and for all.

Man-O-War vs BOSS vs stock 5.0 block

Reply #5
What hp level do you want to hit? that is the biggest factor in which engine to get.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Man-O-War vs BOSS vs stock 5.0 block

Reply #6
Seriously, you need to spend some time doing research over at SBFTECH.  If you would like to get the most out of the money you intend to spend, porting the P heads and building a 331 won't get you bang for the buck.  You'll end up leaving a lot of power on the table for pretty close to the cost of good aftermarket head and a 347.  Later on you'll spend more money to do it right when it doesn't perform the way you expect. 

The cost to upgrade the P head to rocker studs, good valves & springs and have them ported by a quality professional will bring you real close to the cost of a good OTB head (maybe even more).  If you aren't confined to stock head because of a specific racing class, why waste the money? The P head will never make the power of Canfield or TW head. 

A 347 makes more power than a 331.  Cost is the same.

Everyone has opinions and everyone has budgets.  You can build the engine any way you want.  There is plenty of nonsense out on the net and in the magazines which may tell you what you want to hear.  SBFTECH may not tell you what you want to hear, but if you are willing to listen and read the archived material, you may save yourself a lot of time and money.

Good luck with your project.

Man-O-War vs BOSS vs stock 5.0 block

Reply #7
Just re-read your thread and found I miss-read the portion about your heads already being ported.  Read it as: going to be.

Man-O-War vs BOSS vs stock 5.0 block

Reply #8
Even just a fresh rebuild of a 302 with a .030" overbore with those heads should do the trick nicely...sometimes reliability involves keeping it simple...with the right cam and gear, a 2600-2800lb car with a 306 and ported "P" heads can run VERY deep in the 12's...but you'll have to be willing to twist it up a little...if you can afford a 331/347, then go for it...those heads should still make nice power on a stroker and you won't have to rev it to the moon.

Good luck,
Don
Project 3G: Grandpa Grocery Getter-'85 Crown Vic LTD 2-door, 351W with heavily ported/polished GT40 heads, heavily ported/polished Typhoon Power Plus upper & lower intake, Comp Cams 265DEH retarded 1*, FAST EZ-EFI, HD T5, 8.8" 3.73 trac lock with extra clutches, 3G alt. swap, '99 CVPI front brakes, '09 CVPI rear disc brakes, '00 CVPI booster&m/c + wilwood adj prop valve.

Parted & Gone-'88 T-bird Sport, 351W swap, ported GT40 heads

Man-O-War vs BOSS vs stock 5.0 block

Reply #9
Finally someone agrees. I have flogged my combination deep into the 11's on motor and 10.70's w/ spray. The stock bottom end is buzzing around 7200 RPM and I would like to decrease that to a reliable 6200 RPM. I think that a 331 w/ my "already" ported and roller rockered "P" heads that I have tons o'money into cause I have had this same combo since 2000, may be the best way to go. It just costs too much to start all over again.

Man-O-War vs BOSS vs stock 5.0 block

Reply #10
it'll be faster with a 331, but there is no reason not to go with a347 as long as your paying the exact same money. If you get some trickflows, you won't have to worry about your head being your restriction, and you'll have room to upgrade later.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Man-O-War vs BOSS vs stock 5.0 block

Reply #11
If you go with a 347 get the kit with the shorter rod to keep the
 wrist pin out of the oil ring land.
  If the pin falls in the ring land it will cause the rings to wear
quicker.

  So for longevity go with the 331.

 Just my 2 cents.  I would go with a early 302 block or even a mexican block if you could locate 1.




SCT Tuned by Me(Greg@SpeedyDyno.com)

E.T. 10.28 @ 136.5 MPH 1/4 mile: List of Mods; 351 EFI, AFR heads,AOD,Rousch 13in frt brakes,11in rear brakes, AirRide Tech air ride system, Sub frame connetors,2400 RPM stall, 3.50,BBK shorties,T62PT Turbos  air to air intercooled, Home built kit.
Car weights 3705lbs without driver:burnout:

Man-O-War vs BOSS vs stock 5.0 block

Reply #12
Quote
it'll be faster with a 331, but there is no reason not to go with a 347 as long as your paying the exact same money


If you feed the motor enough air and fuel by sizing your combo correctly, the 347 will make more average power EVERY TIME.  Whether or not it's faster depends on the ENTIRE car...

Here's 2 good discussions.....

http://www.foxtbirdcougarforums.com/showthread.php?t=8479&highlight=331+347


http://www.foxtbirdcougarforums.com/showthread.php?t=16679&highlight=350+hp

What kind of budget are we talking about?
What rpm rang do you realistically want to NOT go past?
Do you want streetability?  Emissions? 

Quote
Seriously, you need to spend some time doing research over at SBFTECH.


+1
Best piece of advice in this thread.
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Man-O-War vs BOSS vs stock 5.0 block

Reply #13
460 Man-O-War with Man o war heads with extra head bolts rocks.
Nuff said

Man-O-War vs BOSS vs stock 5.0 block

Reply #14
Quote from: SirChirpAlot;259176
460 Man-O-War with Man o war heads with extra head bolts rocks.
Nuff said


Does anyone else make heads for those blocks besides World products?
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!