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Does anyone know of any strait bottom BT Gt's that are in the 90-100 mph range?

torrent

torrent

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If so what type of HP and drive setup are they runnin? As I may of mentioned before I am rebuilding or possibly starting over just curious what type of power I need to build to be in the ballpark. There are several step bottom speed and HP numbers out there just no strait bottoms. Thanks
 
I can't think of one.

My opinion, based on the same power in straight bottoms vs stepped hulls on the switch-over, the stepped hulls are 6 to 8 mph faster with the same power.
 
I would say some 900's should safely put you in the 90-100 range any day of the week. Are you still planning on staggering the motors? I don't think there is room for staggered motors with transmissions in your rig. Our 43 has a 1ft longer engine room and we barely had room for a short stagger (not a full stagger).
 
Bob did some testing once with stand-off boxes. I don't remember the results exactly, but from what I recall, it was neither better or worse.
 
Coolerman said:
I would say some 900's should safely put you in the 90-100 range any day of the week. Are you still planning on staggering the motors? I don't think there is room for staggered motors with transmissions in your rig. Our 43 has a 1ft longer engine room and we barely had room for a short stagger (not a full stagger).
Click to expand...

I was thinking it was going to take about 900-1000 or so HP. So I guess that will be my target for my engine build. What's your guys thaughts on 557 Cid?
Now the engines are removed I did some further measurements. You are correct there is no way a staggered setup will fit without some major work.
 
I particularly like the part "This vessel is not for the faint of heart, 94 MPH running through 5 foot seas" thaught it was kind of nice of them to add this needed info.
 
So if I go with 557 cid, I would have a stroke of 4.375". I have read many threads stating you don't want to go more than 4.250". I understand the it changes the rod angle.Why is this a bad thing? If it is why would merc go with a 557cid on the 850 SCi?
Jason
 
I think so, that's what I'm trying to figure out. My existing blocks are 454 Gen 6's. I don't think I will be able to build the power needed to get me to the 90-100 mph range. So I think I will need to start over with a new block. But would still like to use my existing 250 blowers, chillers, heads, intakes and carbs.
 
I'm not so sure I wouldn't chat with your favorite engine builder about a swap out for yours......


I am a huge proponent of Cu In's.......


Something like this...



Today, the evolution of this engine species continues to evolve as SAR has released a new 940 ci monster motor that represents the top of the food chain in naturally aspirated engine technology (and price). Representing the top of the mountain in the 5.300 engine family, this new 940 engine, even in this pump gas configuration, provides a number of advantages over the smaller, but better known IHRA Pro Stock engines that have produced the quickest and fastest N/A quarter-mile doorslammers in the world.

"No matter whether it's F1, NASCAR or drag racing, the trend over the past few years have been to go with a larger bore and less stroke in order to move the power band up," said Sonny Leonard. "An 825 ci engine will typically use a 4.800-inch bore with a 5.700 stroke. Here, we're using what cleans up to a 5.080 bore with a 5.800 stroke. As a result, the engine is much easier on the rods, makes more power and actually costs less, too."

Of course, brute power is what any of the 5.300 family of monster motors is all about. Dyno tests on this particular engine showed a whopping 1,702 peak horsepower at 7,200 rpm with 1,357 lb-ft of torque at 6,000 rpm on 93 octane pump gas.

MAybe detune it to 1400HP at around 5600RPM?????
 
WOW, don't know if my budget is up to that kind of Cid. But would be fricken sweet. My engine builder and I are kicking around a few ideas. I'm with you there is no replacement for displacement. But my wee little blowers won't support big cubes.
 
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You'll have to get more feedback, but I'd be worried that small of a pump would make the charge too hot for reliability in a 900+hp engine.


Jason??????
 
You could always go with Sonny's biggest....

SAR 1005 (2150 HP) **NEW FOR 2012**

SONNY'S NEW 1005 CU. IN ENGINE HAS ARRIVED OVER 2150 HP ( NATURALLY ASPIRATED)
THE FIRST V8 ENGINE OVER 1000 CU. IN. ENGINE HERE AT SONNY'S!
THIS MONSTER MAKES OVER 2150 HP,and over 1550 Ft. Lbs of Torque, AND YES IT'S NATURALLY ASPIRATED !!!!

NICKNAMED " THE GODFATHER" Because this is the Big Daddy of all engines
 
Generally speaking, the blower is sized in relation to the airflow that is needed. I don't have any experience with the 250's, but I know that the 420's reach a safe limit at around 950hp on a 572 with a good intercooler. The longevity of the blower will become an issue if you take it that far.

There is nothing wrong with doing a 4.375 or 4.5 stroke on a 10.2 deck. Anything past that and the rod angle does become a concern, piston speed in conjunction with your ring package and how they spaced out, and how long the piston skirt is. A lot of race teams do run the 557. We run the 572, but we generally keep it under 6000 rpm with an occasional burst to 7k and it might see 7500 2-3 times a summer. Just have a good crank (we run a windberg), and a good ring package (total seal gapless tops) with a good set of pistons (hard coated diamond pistons).

A 572 with an intercooled 14-71 should make an easy 950 on pump gas at 6k rpm. You could turn the boost up and spin them a bit harder a probably make around 1150hp or 1200 on 100ll avgas or 110 race gas.

The big CID stuff is cool like Ratickle said. The only is issue is the parts are not readily availabe. It's a custom crank (spread bore), custom cam, hand built sheetmetal intake..... etc, just to name a few things. They do work in drag racing, but the longevity of the ring package may become an issue on huge CID motors.
 
My one engine builder does research developement work for Sonny. He had one of the biggies on his dyno when I was there working on intake and head design (all billet and welded stuff).


I asked him if he puked it on the dyno if he had to pay Sonny the $100,000.......:sifone:
 
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