Help on selecting a new carb

[1BIGJIM]

454 .030 over
9:1 compression
Edelbrock Intake
5,300 RPM MAX
Looking at the HOLLEY 4150 series
750 CFM or 800 CFM?
Vac secondaries or Mechanical?
What is the biggest difference between the two
Thanks
Jim

[rich seibert]

vac. secondaries are good if you are worried about gas milage
mech. seconaries is the way to go in my opinion
.
.
4150 ,if you do the math your engine requires about 810 cfm at 6000 rpm
if your boat is real heavy750 cfm will work best for pleasure boating,
the bigger the carb, the slower the air moves through it

[Taylorman]

Ive been told my a few that the BG Mighty Demon is a great carb. You can get them on ebay with a free fuel line for $500.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&tc=photo&item=7973581514&category=33550

[OMEGA_BUBBLE_JET]

750 holley dp with mechanical secondaries. best all around marine carb. I would spend the extra few $$$ and get a marine version. contrary to popular belief they are different in more ways than just the j-tubes.
Omega <-------runs a 750dp at 5,500 rpm on a BBF

[Foggerjet]

Ive been told my a few that the BG Mighty Demon is a great carb. You can get them on ebay with a free fuel line for $500.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&tc=photo&item=7973581514&category=33550
IMO, Demons are good carbs. I ran one (750 speed demon) on my boat and it ran good. I have an 850 mighty on the bracket car, and it's awesome. However, it required quite a bit of tuning to get it just right. Both shooters were too big and the jetting was way too fat out of the box. I ended up with it jetted at 76 square. It may work great out the box for you, but be ready for some fiddlin' if it's not. After that it will be good to go.
fog

[Foggerjet]

My last post was before I read the listing (eBay). I've heard good things about that seller. They don't screw you on the shipping, only 10 bucks. Plus that fuel line is like $60 from summit and the carb is $500. Seems like a good buy. Watch some of the other carb sellers, as you'll end up with a reconditioned piece. A friend bought one from CNC and he was worried that it would be a recon. but it showed up and it was indeed brand new, and worked great.
fog

[Shallow Minded]

More Upgrades??? Ha, good to hear you're still fightin' the fight.
I've got a similar set up, only add a little B&M 174 blower. Running a Holley 850 and haven't had any problems. Spend the extra $'s for the marine...heaven forbid an engine fire, that's the first thing Mr. Insurance is going to ask about...

[1BIGJIM]

Spent the extra CASH and ordered a 750 SEA DEMON with mechanical secondaries this morning. Supposed to be here Friday.
That will me you see Friday flying up the mighty MO :)

[Shallow Minded]

Spent the extra CASH and ordered a 750 SEA DEMON with mechanical secondaries this morning. Supposed to be here Friday.
That will me you see Friday flying up the mighty MO :)
'Atta boy... it's only money. Bolt it on and you're ready to go.
I'm assuming you got the whole oil cooler/direction problem resolved...

[SmokinLowriderSS]

A 700CFM holley 4150 Mech seccondaries was orriginal on my 454-powered Taylor SS. I kept the carb in the re-cam/rebuild/upgrade this past spring, still liking the power and throttle response. Probably not much diff to the 750, I may get an 800 for certain uses (weekends spent racing instead of skiing) but don't want the added fuel usage. As is I can kill 22 Gal gas in under 2 1/2 hrs if I am so inclined.

[1BIGJIM]

Yes I fixed the "oil cooler/direction problem" with a new engine :mad:
Spun a rod bearing, I had metal everywhere even in the piston skirts.
Saved the timing gears and carb :eek:
Now I am getting rid of the carb....
Things must get better.

[Hollis]

I have the Sea Demon 750 on my Ford 460...What size jets should I be using for lake runs??