Reply With QuoteI figured that after I talked with the local Chevy guy.
sorry I owe you a beer
I was wrong today when I quoted 18k its 13 k for the 720hp my cost the 18k was for the ram jet with fuel injection
I figured that after I talked with the local Chevy guy.
I figured that after I talked with the local Chevy guy.
sorry I owe you a beer
sorry I owe you a beer
No worries bro. Ill drink one anyway.
J
Is that your boat in your picture. I thought yours was all white.
R
J
Is that your boat in your picture. I thought yours was all white.
R
still have the white one trying to sell it got this one 3 months ago
I know my next boat will not have Merc power in it. The price they want for there HP525 is outrageous. I'll have a nice 500-600hp motor built before I buy the new one and save a lot of dough. I wish I would have done it with my present boat.
I was wrong today when I quoted 18k its 13 k for the 720hp my cost the 18k was for the ram jet with fuel injection
Jay,
I am not positive however, I belive Teague mentioned in his tech section that automobile crate motors are NOT setup correctly for marine applications as far as the cam design (Reversion). Have you talked to him about them?
Havasu this weekend? Well be there. (JJ)
Article:
If the cam in your engine is the one provided in the GM automotive crate engine, water reversion might be your problem, since this cam profile is not suitable for marine engines with water in the exhaust.
BLOWER CARBS
Question: I read your recent column with much interest on carburetors with intermediate fuel circuits.
Here's my problem: I have recently replaced the engines in my 40' Fountain with marine-based Generation VI 502 Chevrolets with 256 Weiand blowers, and dual 750-cfm Holley carburetors. The engine is so rich at idle that it is covering my transom with soot. Above 3,000 rpm, it clears out and seems to run fine. The float levels are OK. The engine idles at about 9 inches of vacuum. The timing is set at 8 degrees initial with a total advance of 28 degrees. The camshaft is stock. The carburetors are 4779 double pumpers with two circuits. They are not marine carburetors and do not have J-tubes. They have been boost-referenced in the primaries only. I am really stumped on this one.
Ken Kleitz
Wethersfield, Conn.
Answer: If your engines are running rich at idle, it can only be two things related to the carburetors: Either the idle circuits are out of proper adjustment, or the carburetor is leaking internally. My experience with your setup has been that the idle mixture screws need to be set at about three-quarter turn on the primaries and about five-eighths turn on the secondaries for starters. The 4779 Holley only has power valves in the primary metering block. It is not necessary to boost-reference the power valve on your type of engine. The goal is to make sure the power valve opens soon enough to prevent a part-throttle lean condition.
This can be accomplished on your setup by using a 10.5 power valve instead of the stock 6.5. Remember, the manifold vacuum is not what the carburetor sees on top of the blower. Many times, when carburetors are modified for the boost-referencing, other internal leaks are created. You should be able to make the engine stall by turning the mixture screws in too far or all the way. If the engine idles with the mixture screws turned clockwise until they are closed, there is an internal fuel leak and the carburetor is bad.
You may be mistaken about the carburetors being the problem. If you have a type of exhaust system that reverts water, it will seem like the engine is idling rough and rich as water enters the cylinders and starts causing plugs to foul. If the cam in your engine is the one provided in the GM automotive crate engine, water reversion might be your problem, since this cam profile is not suitable for marine engines with water in the exhaust
I really don't know much about this but I will call the boys at Pfaff and try to get an answer today and check into the marine applications from GM
I really don't know much about this but I will call the boys at Pfaff and try to get an answer today and check into the marine applications from GM
You da man J
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