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79stars&stripes
04-20-2008, 11:14 PM
Hi everyone,
Here is the deal, I have a 1979 stars and stipes with a fresh 351 motor. The block is bored out .030 over, and it has a custom marine cam from comp cams, the lift is .500. I need to buy a new carb for the boat but I don't know what to run. It had a Holley 4-barrell 600 cfm. Do I run the same carb, or should I up grade to something bigger or better. Also do I want mechcanical or vacum secondaries? I have done a ton of research and not found a clear anwser. Any ideas guys? I am really stumped at this point.
Thank You in advance.

Jim@BAWS
04-20-2008, 11:25 PM
http://orlando.craigslist.org/boa/648137323.html


Here is a DEAL on a Carb for your boat

Jim@BAWS

Chas
04-20-2008, 11:29 PM
I will be looking for this in the near future myself. I'm sorry I didn't save the link, but I have seen a real good thread on the differences between some of the carbs which will fit your application. Also a thread - may have been the same one - about the benefits of vacuum and/or mechanical secondaries.

Search search search...

79stars&stripes
04-20-2008, 11:34 PM
Sorry Jim I don't want anything used. Thank You though.

Chas
04-20-2008, 11:38 PM
Here is that thread about vac/mech sec....

http://www.tmcowners.com/teamtalk/showthread.php?t=21961&highlight=secondaries

79stars&stripes
04-20-2008, 11:43 PM
I know i've been searching so much it's starting to make me dizzy! I'll let you know if/when i find any information on this topic.

79stars&stripes
04-20-2008, 11:51 PM
Thank You that thread was very helpful.

Lakeview
04-21-2008, 09:29 AM
Call or e-mail the holley tech line-they are very helpful-don't make the mistake of putting too much carb on,you'll waste money and fuel.

TRBenj
04-21-2008, 12:24 PM
For the mods youre describing a stock 600cfm 4160 with vaccuum secondaries will be just fine. The only thing you might want to consider adding is a metering plate conversion kit so you can tune the jets on the secondaries.

Im pushing 350hp or so (guesstimate) out of my 351w, and I turn up past 5200 RPM on the stock carb without issue.

79stars&stripes
04-23-2008, 01:17 AM
Thank You TRBenj, I spoke with someone from the Holley Tech line, and he recomended basically the same setup. I'm just going to run a marine 600 cfm with vaccum secondaries. Hopefully this will fix my idle problem, if not I don't know what else to do. I assume you are running that 351 W in a mastercraft...? what year/model?

TRBenj
04-23-2008, 09:38 AM
Thank You TRBenj, I spoke with someone from the Holley Tech line, and he recomended basically the same setup. I'm just going to run a marine 600 cfm with vaccum secondaries. Hopefully this will fix my idle problem, if not I don't know what else to do. I assume you are running that 351 W in a mastercraft...? what year/model?
What about your original carb? Did you try a rebuild? Even a new carb will take some dialing in to run properly- dont expect to simply bolt it on.

Your assumption would be wrong... its a '90.

79stars&stripes
04-24-2008, 11:16 PM
i used to work at a shop that built racecar engines. (ProPower Racing) when i took the old carb in they said it was not worth rebuilding. the reason was the carb was old, and it was just not worth it. I got a 650 double pumper street avenger from a friend that was brand new, and i had someone dial it in for me the best they could. The boat does run out well, but the idle is just not right. From the research i did, i guess that that carb is for a street car app, and with the angle that the motor sits on at idle, the floats could not be adjusted accordingly. I also had a decent exhaust leak that was do to the manilfolds, which i replaced this year. I have not yet messed with the carb after fixing the leak. If i can get the boat to idle well with what i have, then i would just run the 650.

DemolitionMan
04-24-2008, 11:50 PM
I have the same problem as you. But I have a new carb sitting in my shop I will put on this weekend.

TRBenj
04-25-2008, 01:48 PM
i used to work at a shop that built racecar engines. (ProPower Racing) when i took the old carb in they said it was not worth rebuilding. the reason was the carb was old, and it was just not worth it. I got a 650 double pumper street avenger from a friend that was brand new, and i had someone dial it in for me the best they could. The boat does run out well, but the idle is just not right. From the research i did, i guess that that carb is for a street car app, and with the angle that the motor sits on at idle, the floats could not be adjusted accordingly. I also had a decent exhaust leak that was do to the manilfolds, which i replaced this year. I have not yet messed with the carb after fixing the leak. If i can get the boat to idle well with what i have, then i would just run the 650.
Dont forget that an auto carb is also a huge safety hazard. They sell marine carbs for a reason.

454Prostar190
04-25-2008, 02:33 PM
The boat does run out well, but the idle is just not right. From the research i did, i guess that that carb is for a street car app, and with the angle that the motor sits on at idle, the floats could not be adjusted accordingly.

I have a Holley 750 Double Pumper on mine and it has a wedge under the carb to give it a flatter angle. I've seen wedges for sale and it may make the difference that you're looking for. Looks pretty cool too:D Something to think about. Rick