Jetting question for E85 Dominator?

[70 RR]

Hi everyone,

I have a 63 Sport Fury with a 505 stoker 12 to 1 compression and a pretty hefty cam (625 lift, 273 duration @ .050) Super Victor intake and a 1050 Dominator steup for E85. I bought the carb from a local engine builder who has a guy the sets them up for E85. I'm not exactly sure what jets came stock (84s or 88s front and rear) but supposedly the carb was tuned to my motor and 106s were what he installed. I know E85 requires more fuel and therefore larger jets but this is ridiculous! I run an AEM A/F gauge set to read in Lambda and this thing runs "PIG RICH"! I can get to idle at .9 lambda (13.23 a/f) but once l begin to drive, all hell breaks loose. If l am just cruising along without giving it much pedal I'm right around .83-.85 (12.15-12.35 a/f) which where you want to be at WOT. When l try to get on it the least little bit l spike to .69-.73 (in the low 10s- high 9s range a/f). My question is, are any of you guys running a similar application now or in the past that can help me dial this Dominator in? I tried taking out the 106s and replaced them with 102s and there was little change if any. I am so frustrated because this is a great running machine and l really like the price of E85 as opposed to race gas or 93 and octane boost. Thanks!

70RR

 

[Bigal75]

Are you running a power valve? To tune wot take the PV out, square jet the carb until you get the best mph or af ratio if you're not on the track. It will run like **** at part throttle.

Once you have the correct jetting at wot, do the same on the primary side until you get it where you like it on the main circuit.

Next step put a PV in it and adjust the restrictors until you get your wot ratio or mph back.

Start with a 6.5 PV, check your af ratio, you will notice that on light throttle high rpm the engine will lean out. Choose a power valve that fills in that gap.

There's a heck of a lot more to tuning than this such as air bleeds, and passage restrictors but this should help you out.

Do you know the size of the air bleeds? 2 or 3 circuit?

 

[451Mopar]

Hi everyone,

I have a 63 Sport Fury with a 505 stoker 12 to 1 compression and a pretty hefty cam (625 lift, 273 duration @ .050) Super Victor intake and a 1050 Dominator steup for E85. I bought the carb from a local engine builder who has a guy the sets them up for E85. I'm not exactly sure what jets came stock (84s or 88s front and rear) but supposedly the carb was tuned to my motor and 106s were what he installed. I know E85 requires more fuel and therefore larger jets but this is ridiculous! I run an AEM A/F gauge set to read in Lambda and this thing runs "PIG RICH"! I can get to idle at .9 lambda (13.23 a/f) but once l begin to drive, all hell breaks loose. If l am just cruising along without giving it much pedal I'm right around .83-.85 (12.15-12.35 a/f) which where you want to be at WOT. When l try to get on it the least little bit l spike to .69-.73 (in the low 10s- high 9s range a/f). My question is, are any of you guys running a similar application now or in the past that can help me dial this Dominator in? I tried taking out the 106s and replaced them with 102s and there was little change if any. I am so frustrated because this is a great running machine and l really like the price of E85 as opposed to race gas or 93 and octane boost. Thanks!

70RR

With E-85 your lambda should be around 0.80-0.90.
Problem I have been having id finding E-85 that is 80+% Ethenol. Usually it is 70-75%?
http://www.n54tech.com/forums/showthread.php?t=22216

 

[70 RR]

Are you running a power valve? To tune wot take the PV out, square jet the carb until you get the best mph or af ratio if you're not on the track. It will run like **** at part throttle.

Once you have the correct jetting at wot, do the same on the primary side until you get it where you like it on the main circuit.

Next step put a PV in it and adjust the restrictors until you get your wot ratio or mph back.

Start with a 6.5 PV, check your af ratio, you will notice that on light throttle high rpm the engine will lean out. Choose a power valve that fills in that gap.

There's a heck of a lot more to tuning than this such as air bleeds, and passage restrictors but this should help you out.

Do you know the size of the air bleeds? 2 or 3 circuit?

Hey Al,

Thanks for the device. My carb has no power valves and it is a two circuit. I ended up using .098 jets squared and did some fine tuning on the idle screws and float levels and the car is running pretty good now. Here is a youtube video a friend of mine took of me leaving a car show. Unlike everyone else that was all about smoking the tires, I was taking the opportunity to try and see how the car would launch with the old style bias ply street slicks!

John

BTW I also added a lot more initial timing, the alcohol seems to like 32 initial 46 total.

 

[70 RR]

With E-85 your lambda should be around 0.80-0.90.
Problem I have been having id finding E-85 that is 80+% Ethenol. Usually it is 70-75%?
http://www.n54tech.com/forums/showthread.php?t=22216

You're right 451, you never really know what you are getting out of the pumps. There are stickers on our pumps that say minimum 51% but I would think that is in the winter.