38 flat deck with 33o´s
 

anyone know how fast a flat deck 38 with 330 hp 454´s would go....wasnt that base power back in the day_

454 (basic motor) is corect but 330hp - i'm not shure. I think 454/420hp /TRS maybe 52-54 mph with this. With 330 you better go sailing ;)

I would say 55 to 60mph

You are talking a 12000 pound + boat with a 24 degree deadrise.

That's the same weight of the older Formula 34 PC (top speed mid 40's) but they also had much less dearise.

Another reference point is the Formula 272 SR1. It weighs in about half the weight and runs mid 60's with the 330's.

I think you would be in the 40's with a flat deck. Still would be a cool ride though and look/sound good at the docks.

mine 38 flatdeck " had " worn out 454's with TRS drives and ran 60 on the GPS speedo . the engines did have cams with carbs and were in bad shape on compression and valve springs were gone .

now we have just finished the new engines going on the dyno in a week , should be 800 hp range with 871 blowers and konrad drives .

ok how about 420 hp (good engines)

Its depending on the drives. With TRS i bet 52-54. With Konrads or Bravos run faster. Also depends of water - its a non steped bottom so you need churned water for good top speed.

FWIW.....I think you might see mid 60s with 420s.....maybe...a flat deck is a heavy boat with no transom notch...It would be a pig with 330s for sure. Hell twin 330s only push my 29 outlaw to 64 GPS and weighs half what a flat deck weighs....

38 Flat Deck
 

I know a guy had a 84 Flat Deck brand new with 400's (Really 370's) right out of the box.........56 MPH Tops. Probably would have gone a little faster as is only had the old style Clevers on it.

My Mistress has around 480 hp and runs 64.8 best so far...

I would guess...

flatdeck with 330's 48-50 best, nowhere near 60, I have no idea where that comes from....

flatdeck with 420's I would guess 55-57 tops in good water...

mistress with stock 400/420 normally run 60-62

I wonder where I`ll be, I think I`m 800ish hp

per motor ? or total both motors ?

My 85 Flat deck is a Kevlar boat. I'm running a pair of tired 605 cu.in. tall decks originally 725hp each and No. 3 drives. The best I got out of this combination on GPS was 73 mph. I am fresehening the motors hope to dyno out at 750 hp ea N/A . I am also raising the X dimension 2 inches and hope to see somewhere between 80 and 84 mph.
Rick G.

Per side

i figure the same as RICKG , mine is a flatdeck also , hp on the motors should be 800 ish , i also have konrad drives ( which are shorter than TRS )i have removed unnessecery parts like water tanks,generator and other non used parts . i guess mine will be 80-85 mph range . i will have the props labbed and work with bblades on props when i have the final hp off the dyno . these speed numbers are in a altitude of 1000 ft .

and my motors are forced injection and FI .

These boats definitely take a lot of power. You definitely need 500-550 hp per side to have any chance of seeing 70, and around 700-725 to crack 80. The Mistress, anyway, loosens up as you get near 90, so you can get there with about 850. At that point, unless you have V's or other surfacing drives, you're about done no matter how much power you put in. With the right drives, you need 1000 hp per side on the mistress or about 1050-1100 on a flat deck to crack 100.

Shoot 1050 -1100 more power and $$$ then i want to put in the boat
If I needed another 100 mph boat I wouldn't have gotten a Cigarette LOL Looking for the ride i the slop

I dont think Cigarette would have ever put 330's in there. At the very least it would have been 370's. What makes you think they are 330's?

agree, unless someone had bigger then put 330's in it to sell back in the day..

38 W/330's
 

I had a buddy that bought a brand new 1985 35 Mistress with 330's and I was suprised to see that. I rather doubt as well that a 38 would have been sent out without power to get it well into the 50's at least.

yes, the base Mistress had 330's, m ine did from the factory...

Dave,
Drop it off and we will have you in the 100 mph club for the spring run.

But my other boat is in the 100 mph club...this supposed to become the classy lady fuel mizer :)