Thoughts on this combo for E85

-
hemichuck

hemichuck

Well-Known Member
Joined
Jan 12, 2012
Messages
991
Reaction score
127
Location
Louisville Kentucky
I have a 408 short block that I've had built for a while with a forged 4 inch crank, eagle rods, and Icon 4.03 bore flat tops with valve notches with zero deck.Problem being that I built it in a magnum style block (don't ask what I was thinking)which means with the closed chamber Edelbrock Magnum style heads I have it will be pushing around 12.2/1 compression. I also have a Edelbrock Performer RPM airgap and a Comp cam part # 20-746-9 which has 506 lift and duration of 265 on intake and 273 on the exhaust. I am trying to salvage my mistake with the compression and maybe try to run this thing on E85. This engine is going in a 1970 Dart Swinger with an automatic trans. The car is an original air conditioning and power steering, power disc brake car and I plan to retain all of these options. I will be running 3.23 gears and plan on driving the car a lot. It will probably never see 6000 RPM. I would like to know what the current thought is on this combo and what could be done to improve on it. I already own all of these parts so I am trying to use them up. Also would love to hear any advice on running E85. Am I barking up the wrong tree? or should I back up and punt?
 

Send a P.M.to 70AARCuda/ Tony. He runs all three of his small block bracket cars,on E85. He seems to like it,a lot....
 
Do you have E85 stations where you need them? My understanding is that they can be few and far between in some areas. I see several listed around Louisville, but we have exactly 1 in this whole end of the state that is 25 miles away, and it's 50 miles to the next one. Might suck if you like to travel. It would suck to jump out of one problem and into another.

BTW, it seems like it would easy to just sell those ICON pistons and use another ICON like the IC983, and step to a .039" thick head gasket and you are at 9.9 SCR and the DCR is down in the low to mid 8's. (Assuming a certain deck height of 9.585".) You have a choice of several other ICON pistons to lower SCR to various levels around 10:1 or less, and with a couple of deck heights. Seems like the cost difference of selling your present ICON's and buying lower SCR ICON's would be the same or less than the E85 conversion. Then no issues with finding E85.
 
I guess the big problem with changing the Pistons is that the assembly is already balanced and I really don't want to get back into re-balancing it. Last time I took anything to the machine shop to get it balanced, I ended up picking all the parts up 2 years later untouched. The guy there ask me when I needed it done and I told him 2 years ago. I thought about dropping the rotating assembly into a non magnum block which would require some machining but no re-balance but then I don't have any non-magnum heads right now. Around town the E85 is not a problem but I wouldn't want to head out on a road trip needing it. Maybe switching blocks and buying some new heads is the answer. I actually already have a set of dished stroker pistons and another set of eagle rods that I could put back in the magnum block, all I would need is a crank.
 
What ICON pistons model do you have? If you go for the dished ones versus the flat tops, the bobweight for balancing will go down, and so all that will have to be done is to remove some material from the crank counter weights. It is easy to figure up the new bobweights, and you take that and just the crank to a COMPETENT shop. Ours was in for a bit over a week..... all of $95 to balance the crank to the bobweight number that we figured up and gave them. Eagle has a balance card example on their site and all you have to do is follow the formula for bobweight. It ain't rocket science. ("All you gotta do"... ain't those great words? LOL)

The KB pistons and pins come pretty well weight matched and close to spec, and it is easy to check at home or work on a gram scale. Ditto for new Eagle rods.

Edit to add: Or you can just buy a different set of wrist pins and end up at the same bobweight and not fool with the re-balance. I think I see some on Ross wrist pins on Summit right now that will just about compensate the piston weight change.
 
Do you have a carb that is converted to use E85 or are you buying a new carb?
 
You must log in or register to reply here.
-

Back
Top