2bbl to 4bbl

[Hydraboss]

Can't find anything on the board...has anyone ever changed out the 2bbl on a 2002 VP4.3gl for a 4bbl? Is it a major job? What's required to complete the change? Any help would be appreciated.<br /><br />Hydraboss

 

[Don S]

Re: 2bbl to 4bbl

Down the page around halfway is a post titled "Winter project, upgrade my pathetic 2bbl to a 4bbl. " The information in that post is applicable to a V6 as well as a V8.

 

[jimmbo]

Re: 2bbl to 4bbl

hey great to see someone else from edmonton<br /><br />I got a 4bbl to replace the 2bbl on my VP 5.7<br /> http://www.holley.com/HiOctn/ProdLine/Products/Marine/FMS/FMSC/0-80552.html <br /><br />Here's one specificly for your motor<br /> http://www.holley.com/HiOctn/ProdLine/Products/Marine/FMS/FMSC/0-80492.html <br /><br />Biggest job is to replace the intake manifold. The throttle linkage bracket on the VP has a bunch of holes to accomadate a variety of carbs. Just make sure you use a marine carb, not something you found at Pick a part

 

[Darrendude]

Re: 2bbl to 4bbl

Isn't a 650 carb abit over kill for a v6?

 

[jimmbo]

Re: 2bbl to 4bbl

I made a error on the link for the carb for the 4.3. I replaced it withthe correct link. The new link is for a 600 cfm carb. Vaccumn secondary carbs will only flow as much air as needed. Same goes for the Q-jet, which has mechanical secondaries and an air valve. Most models can flow 750 cfm, and some were designed for 800 cfm. However very few engines will need that much. But the Q-jet has been OEM on engines as small as the 3.8 litre and as large as the caddy 500, very forgiving on engine size.

 

[John_S]

Re: 2bbl to 4bbl

Look at the Edelbrock 1409, as well. The 1409 comes jetted for small blocks, like many carbs, but they have a Merc 4.3 jet and metering rod kit for it.

 

[Hydraboss]

Re: 2bbl to 4bbl

Thanks for all the replies. Jimmbo, it's nice to see someone else that thinks spending 25k for a toy you can use for 3 months is a smart thing to do.<br />Is there anything special about changing intakes/carbs on marine engines that I should know about. I used to do the Edel Performer change-outs on my old Camaros with a shiny set of beer-wrenches and one friend who knew what he was doing. Making sure I buy marine parts is a no-brainer (which matches my mechanical abilities perfectly), but what about lines, linkages, etc... Anything marine-specific about them?<br />Jimmbo, where did you order your carb from? Edmonton or online?<br /><br />"Only 3 1/2 months until Wizard Lake opens up...must...hold...on!"

 

[jimmbo]

Re: 2bbl to 4bbl

My cousin (owns a tranny shop) ordered for me from Dix performance (wholesale side of JB automotive) so I got it wholesale. Best retail price I could find was at Protec on 126 ave and around 124 st. Best online prices I could find were at Summitt Racing. <br /><br />As for the swap, use GOOD quality gaskets. As for marine specific parts. Fuel lines might have rules, but linkages aren't under that reg. Which manifold are you looking at?<br /><br />Wabamun is open year round ( untill 2010 ), and I usually am out by 2rd week in April and usually keep boating until early november.

 

[rodbolt]

Re: 2bbl to 4bbl

the fuel lines have specific rules plain rubber with hoseclambs are not allowed between the pump and carb. and the carb must be USCG marine rated.<br />other than that check the cam part numbers between the 4bbl version and the 2 bbl version. sometimes the cam specs are much different and adding a 4bbl carb and intake to a two bbl cam and heads will kill your performance

 

[Darrendude]

Re: 2bbl to 4bbl

4bbl manifold for 4.3<br /><br /> http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=4521528011&category=50442