E85Forum.com

ambulocetus · Joined: 17 Apr 2010 Posts: 2 Location: indiana

Hi all, I have a 62 Buick Skylark. Old timers might remember this car as the one with the little 215 aluminum V8 that was later sold to the British and put into Land Rovers and MGs. This engine came from the factory with the same carb that was used on the big old nail-head and is really more carb than the engine needs. Since this carb is so big, I'm wondering if I would still need to do internal modifications to enable it to run E85, or can I get away with just a bigger fuel pump? I suppose I could just fill it up and find out the hard way, but it's my baby and I don't want to do anything I may regret. Thanks in advance.

murphinator · Joined: 08 Jan 2010 Posts: 93

theres a couple carb experts here that can answer your question as well as at least one that converts carbs to run on e85 ( you may want to do this to a spare carb)

you can also run e85/gasoline blends which depending on ratio could allow you to run your carb as is , the less e85 the closer to gasoline stoich

straight e85 will require around 30% more fuel but a 50/50 blend would require around 15% more fuel for example
_________________
PB's 1/4 mi 12.209, 117.75 trap ,1/8 mi 7.76 ,93.99 trap , 1.949 short time 4.53 0-60

I tune with HP Tuners software

ambulocetus · Joined: 17 Apr 2010 Posts: 2 Location: indiana

well it's the same carburetor that was used on the famous 409 engine, which is almost twice as big as my little 215, so I'm thinking it may flow enough. Is there any risk to just filling it with E85 and seeing what happens? I've run it on 50% E85 and 50% Amoco Ultimate with no problems. Is there a kit for carbureted engines? I'd like to have the option of switching back and forth from gas to E85 without swapping carbs.

Alcohol · Joined: 17 Apr 2007 Posts: 634 Location: Central Wisconsin

It might flow more but you can pretty much bet the carb was jetted down to the airflow/fuel needs of your current engine on gas. At a minimum the jets and accelerator pump will need an upsize. Like Murph- I would rather the cab experts answer the specifics of this one.

Thumpin455 · Joined: 04 Oct 2008 Posts: 227

It would be difficult or impossible to have a flex fuel carb since its a bit more than jetting changes to convert a carb properly. Carbs dont have on the fly tuning, you have to get inside and make changes, and the differences in ethanol and gas are more than most automotive carbs can handle without some help to flow more fuel. The passages are simply too small and they become the restriction rather than the jet.

If I remember correctly you should have either a Carter AFB or a Rochester predecessor to the Qjet, the name escapes me. Both of those carbs have air valve secondaries that will only flow as much air as the engine wants/needs, so you can use a somewhat larger carb on a smaller engine, and really the 409 with a single carb was a bit under carbed.

You have to match the fuel to the airflow, and just because it is a smaller engine doesnt mean it needs less fuel and thus smaller jets. If you jet it down farther than it wants it will be too lean and it will surge or not run at all. I have a couple 850 Holleys that I got dirt cheap because they couldnt get the to run right on their 350 sbc, might have been the 52/56 jets they had in them. It runs much better with 82/88 jets because it needs to match the airflow and fuel, and the small jets simply werent enough fuel no matter what size the engine is.

If you have the Carter they are simple carbs and would be easy to convert, the Rochester carbs are a bit more complex with more tuning variables, but they will still work. One thing you could do is have Mark (DragChevette) set up a Holley for you, or modify one yourself if you know carbs relatively well, and run that with E85, then keep your stock carb for gas. You should have a square bore intake, not a spreadbore like a Qjet so the Holley should bolt on easily.
_________________
1970 Pontiac GeTOh 455 with a Qjet.
1998 Pontiac Formula LS1 on yeast pee.

murphinator · Joined: 08 Jan 2010 Posts: 93

boy this would probably be a hack way to do it but what came to mind was tri power with 3 equally sized 2 barrels run the front and rear 2 only on gas and add the middle one to the mix with e85.

if they were equally matched adding the 3rd carb would add 33 1/3 % more fuel just about right. put a shutoff valve on the fuel line to the middle carb , solenoid ,etc... to open and close fuel delivery

how to go about getting equal fuel distribution to all 3 carbs and if you would need to stop airflow through the middle carb I dont know - I am an efi guy but if its not a dumb thought which it may be Laughing

the guys to tell you how to implement it are on here Cool

thinking more you may just need to connect the linkage for carb #3 for e 85 and disconnect it for gas ???

if you e85 carb guys can make a flex fuel carb system out of this I am getting royalties Wink

_________________
PB's 1/4 mi 12.209, 117.75 trap ,1/8 mi 7.76 ,93.99 trap , 1.949 short time 4.53 0-60

I tune with HP Tuners software

Eric68 · Joined: 01 Nov 2007 Posts: 331

I'm sure Mark or I could convert a like carb to E85 for you if you have a spare. Then you could just swap back and forth between carbs if you wanted to 1) preserve the value of the original carb or 2) go back and forth between E85 and gasoline.

What carb is on it anyway? A Holley O-3310?

Sorry for the slow reply, just give me a shout if you still need some help. Phone number is on my website.
_________________
E85 racer and E85 carb builder
www.horsepowerinnovations.com

E85 powered 68 Camaro street car
Best ET on motor 9.96 @ 133 MPH, 5.92 on N2O in the 1/8th

keith2500hd · Joined: 20 Jun 2010 Posts: 4

it should be rochester 4g or carter wcfb, if i remember they had small 4 bolt pattern. would just need adapter plate. might need to change thermostat, since this is aluminum engine.