Big HP longevity

[CrazyHippy]

How long does 750HP last b4 it needs rebuilt?
Just in general, assuming good parts, and no breakages.
How about 1000HP?
1250HP?
Thanks
BJH

[78DiMarco]

I'm no engine builder but I have a freind that has a PF 532CI BBC that was built in 1996. It makes 850HP and this thing has been pretty much turnkey ever since he got it. He runs the blower at about 10 under and changes the oil when needed. This thing still runs perfect and looks perfect. I don't know how many hours it has but I would guess about 100 or so. Not bad if I do say.
I have a twin turbo I rebuilt a year and a half ago. It has about 700HP and time will tell how it lasts. The motor before the rebuild was about 20 year old.

[BOFH]

It depends on how it was built. You can "build 750hp for $3000, and it may last a summer. Or you can spend $15,000 for 750, and it can last years.
If you want longevity, look at the way a NASCAR engine is built. It runs at WOT for 8 hounrs at a time, and usually lasts a full season. Build a NASCAR engine with less compression, a less aggressive cam, (and a few other changes) and you could have 750HP for 10 years. It will NOT be cheap...

[Clown]

It really depends on how hard you run your shit.!
And how much on the cutting edge your tuneup is
I've had a motor that makes 780hp and three seasons
It has lasted. The Spring pressure went away this year The guides are starting to push a little oil.
"And I no that the Roller lifters are in need of Replacement. Just from exeperiance"
The Pistons Crank Rods Cam Block & Heads
Are off of a friends OFFshore boat , This stuff is from 1981-82 And still in good shape.
Does anyone remeber when Carl Foltz Was doin heads out of his garage? These are those heads.
There is evan an Old Kiekafer crank in that motor.
I know I didn't answer your question but I have found that most of the hard parts LAST Awhile with proper maintence. eek!

[Clown]

BOFH:
It depends on how it was built. You can "build 750hp for $3000, and it may last a summer. Or you can spend $15,000 for 750, and it can last years.
If you want longevity, look at the way a NASCAR engine is built. It runs at WOT for 8 hounrs at a time, and usually lasts a full season. Build a NASCAR engine with less compression, a less aggressive cam, (and a few other changes) and you could have 750HP for 10 years. It will NOT be cheap...I agree $3,000.00 summit 750 hp that last's one season.
And $20,000.00 Sonny leonards 750 hp that last's years.

[Unchained]

Clown:
It really depends on how hard you run your shit.!
And how much on the cutting edge your tuneup is
I know I didn't answer your question but I have found that most of the hard parts LAST Awhile with proper maintence. eek! I have to agree with that, I have run the blown 540 Arias for three seasons and it still runs great but I don't hold it wide open for longer than 10 seconds at a time. Most of the time I'm just cruising around at 3500 rpms or less.
I am big on checking cranking compression and all 8 cyl's are within 5 lbs. same as it was at original assembly.
I check plugs frequently and correct anything thats not right.
Mark

[gnarley]

[QUOTE]Originally posted by BOFH:
If you want longevity, look at the way a NASCAR engine is built. It runs at WOT for 8 hours at a time, and usually lasts a full season.
Well they don't last all season in cup cars & don't run 8 hours at a time, it's more like 3 to 5 hours of hard running & are torn down inspected & freshened after every long run or race. In the less competitive series engines may last a season with some help or a freshen or 2 during the season. The bottom line is they are built to take it with the best of EVERTHING & parts are inspected to the nth degree. Any pieces that aren't acceptable are shipped back to the mfg or sold to parts brokers who resell them to others. I might be going out on a limb here not knowing much about big time marine engine suppliers but I suspect most of the best marine engine builder’s shops pale in comparison to the best shops like Hendricks or Roush who lease & sell to other teams. The best marine shops probably don't do all the prep work of the cup shops as they can't pass the cost on to most users

[canuck1]

Our race motors run about 12 hours before freshening with the valve springs being changed every 3 hours run time
cruising at 3500 is alot easier on parts than running wide open all the time
Run the best parts you can afford and check things over every time you have a chance to

[LVjetboy]

Alrighty then. Guess my mild little 340 hp BBC w/NOS is good for 11 MORE YEARS
jer

[Clown]

The best marine shops probably don't do all the prep work of the cup shops as they can't pass the cost on to most users
--------------------
Gnarley Charlie
1994 Fourwinns Liberator 201
Blown 454 King Cobra
I'm going to disagree with you I ORIGINALY Started playing with boats because of a job at a marina I had
Polishing boats after school the guy seen that I had an interist in wrenchin so he started letting me pull motors apart for the mechanic to be rebuilt
One thing led to another and 2 years later , I was his top engine builder. We were making at the time serious Horsepower 1100hp on 89 oct gas 6 pounds of boost. And he made me check everything over with a fine tooth comb. Some things that I would argue with him about saying this aint going to make a bit of differance. But it did.
Parts where chscked and rechecked everything was modified for the application.
He had a friend that now builds winston cup motors
give some advice on proper cam .
So I say that you just have to find a good well liked machinist to build your stuff or talk his ear off.
Thank you.