What A/F ratios are you guys seeing that work well for a Naturally Aspirated BBC?
My engine seems to want a richer mixture on the ramp up to WOT, (about 3/4 throttle) then it actually does at WOT itself. Is that normal?
I hooked up an AEM wideband setup in order to monitor/tune my engine. 476 BBC, 9-1, aluminum oval port heads, dual plane intake, 850 quick fuel marine, Berkeley jg A- impeller fresh from MPD, 5400rpm wide open.
at around 3400-3600 I'm bouncing between 12.1-12.6 on the meter, wide open it was...
So picked up this boat a couple weeks ago. 1983 17' Targa, full stringers, berk E pump, has a fin, kinda of a cool little boat. I have owned outdrives and outboards before, this is my first jet. Took it out to Inglebright the other evening for a little cruise and the steering feels really...
Hey all, about to rebuild my 350 engine that's running a 671 Weiand blower and wanting to know what compression ratio to build it to. It is in a family jet boat that does a race or two a year so it needs to run on 96 or 98 pump gas, has 76cc cast heads, comp blower cam #12404-4 but I would like...
Curious what compression ratio (and cam specs) you guys are getting away with on pump gas? I am in the process of building a 468 chevy for my Hondo and trying to decide what kind of compression I want to end up with. I want to be on the edge of pump gas, don't mind blending, but do not want to...
What is a safe CR for a pump gas 496. I have been told from 10.5:1. Then another said it would rattle at the CR. What is safe for 91 pump gas? About to order pistons and want to stay safe. This is for a lake boat with a little NOS. Thanks for your help.
I have a 20ft eliminator mini day cruiser with a turbo 400 and a 461 bbc. built for lake putting and ski time. I have a 12/14 3 blade prop. my racing days are over so the best gear for the all-around would be appreciated. Thoughts?????Thanks in advance! Mark
I was wondering what octane I would get away with running if I went with another set of L88 427 pistons just ones designed for the open chamber heads this time around.
Could I buy C12 and just mix it a little with 91 pump gas. If so what ratio.
These are the pistons I'm thinking of going...
Ok, trying to figure out compression ratio on a proposed build, maybe need an education on the subject. Have a couple assumptions I need help with.
Inch to cm conversion is inch x 2.54?
Volume of a cylinder is: stroke x 3.14159 x 1/2 bore squared, right? Of course must add in head gasket cc...
This is a really general question, I'm just looking to keep my motor "safe" or ideal. And help me get my motor jetted right.
It's not a balls out race motor.
I have a 496 with a GM 671 blowing about 5psi and two holly 750cfm 4150s. Just say 6500max rpm. I just run premium
yes I know it...
Alright folks, up for sale is a very clean Mercruiser Bravo I outdrive, complete and in good condition.
I will be getting some pictures of it tomorrow sometime. I needed one and ended up with two.... Story of my life...:duh:
It is mid to late 80's and is a solid 9 out of 10. 1.50:1 ratio, no...
Hi all, my first post. I have recently purchased an 18'6" Everingham shallow vee boat
Looking for suggestions on step up ratio and prop.
Motor will be injected LS3, 620hp @ 6,300 & 576 ft lbs @ 5,100
thanks in advance
Can someone explain any tradeoffs in gear ratio vs prop pitch? Example, adding power to a not ideal ratio (too steep) could be overcome by propping with a longer pitch... But is there some issue that limits this? Cavitation or something? Otherwise they wouldnt sell other gear ratios I guess ?