4.3 2-bbl to 4-bbl conversion *UPDATE*

[eja]

Hello All,<br /><br />I wanted to update my progress, and ask a couple of questions to Bondo and RED regarding the conversion (see "4.3 Wake-up"....posting). I decided, based on brackets, $$, and estimated power to convert my (pre-vortec) 1986 OMC_Cobra 4.3 2-bbl (175 hp) to 4-bbl via Edelbrock 2111 Intake and Edelbrock 1409 4-bbl. Well, looks like the brackets need some messaging. My 1/2 day project has taken on more depth (as usual). According to Edelbrock, I should be at 260 Ft-lb Torque and 202 HP when I'm done...can't wait.<br /><br />Does anyone know if there are "factory" brackets for the 4-bbl OMC Cobra 4.3 linkage available for purchase? I don't really want to Hack-Up my 2-bbl stuff in case I want to go back B4 I sell it (in the future)....<br /><br />Thanks,<br />Erin

 

[Bondo]

Re: 4.3 2-bbl to 4-bbl conversion *UPDATE*

I really Can't Help with the OMC stuff,.... I Don't Think they ever used the Carter Clones for Carbs........<br /><br />And,... I Don't Know if a bracket off a Holley, or Rottenchester will even bolt up, or work......<br /><br />202hp is about Right,... Merc. rates it at 205hp.....<br /><br />Have you found the Edlebrock web page for "Tuning" that carb,..??...<br />It's a Really In-depth manual.....<br /><br />If not,.... Let me know,+ I'll Dig it Up....

 

[eja]

Re: 4.3 2-bbl to 4-bbl conversion *UPDATE*

BTW:<br />The other difficulty I ran into was that the thermostat housing bolts are not aligned the same on the EB intake, and this offsets the cooling lines for the exhaust manifolds enough to be in the way of the alternator! I think we're going to space the Alt out 5/8" and run 1-belt...bummer.<br /><br />I found that my lower outdrive froze and cracked! DANGIT! Can't win. Not sure if we can just weld it back, or if is some important bearing surface of something.... Do you think, if I find a deal on a complete outdrive, that it would be beneficial to change the ratio to that of a 5.0? The shift-prop would rev faster.... just a thought..

 

[Bondo]

Re: 4.3 2-bbl to 4-bbl conversion *UPDATE*

Ayuh,..... Well,......<br />I Guess you're going to have to wait for some of the OMC guys to Help you out........<br /><br />You've gained alittle HP,...... I Really Doubt you need Taller Gears......<br />I Think it would put the ratio so tall,.. the Torque-Shift wouldn't be pitched Small enough in High Gear.....

 

[eja]

Re: 4.3 2-bbl to 4-bbl conversion *UPDATE*

Thanks Bondo

 

[KaGee]

Re: 4.3 2-bbl to 4-bbl conversion *UPDATE*

The lower gear ratios are all the same in the V6 and V8's. <br /><br />Depends where the crack is as to if you can weld it. Ebay always has a lot of Cobra stuff on it. <br /><br />As for the your other problems, chit's what happens when you begin to do mods. OMC throttle brackets are gonna be hard to come by new. Your best bet is a boneyard or Ebay.

 

[eja]

Re: 4.3 2-bbl to 4-bbl conversion *UPDATE*

Yeah, I THOUGHT I had done all of my homework, but I was *originally* planning to buy a stock intake.... probably would have made it a little easier, but I wanted to squeeze in those extra few horses, since I didn't go vortec..<br /><br />Thanks for the info.