950 HP on E85 - idle taking off

Posted By: 69dart

950 HP on E85 - idle taking off - 05/06/10 06:37 PM

Hey guys I finally got my car out yesterday for the 1st time this year. I had to rebuild the engine and I upgraded the brakes over the winter so I was pretty anxious before hitting the track. Luckily everything went very well and the car ran great. The 60 ft's were off almost a tenth from the fall but the track was green and the wife could see the car black tracking all the way down. The car still picked up about 2 MPH over last year and there was a pretty nasty crosswind so thats encouraging. I was hoping to pick up a bit more ET but I think it will come as the track conditions improve.

Anyway a couple things I did have trouble with. The car idle's fine but if I rev it up to clear it out the idle doesn't come back down. It kinda takes off on its own to 2500 or so. Its fine in gear the idle stays pretty steady. Also the car was very hard to start a couple of times. I'm kinda thinking a needle seat could be sticking but they were just replaced in the fall. Plus I never changed plugs and I probably fouled them out trying to start the car over the winter funny story (I left the car outside while we drywalled the garage but it ended up snowing 6" while we were working and we couldn't push it back inside so I tryed to start it. Note it won't start on E85 when it 20 degrees out. We ended up having to use the CRV to push the car through the snow back inside - that was crazy)

Anyway could the air bleeds be a factor? I haven't changed the air bleeds from the factory gas settings after using the Quick Fuel kit to switch to E85 last year. Whatcha guys think?

I only have a couple more days to tune until the Classic. I can't believe its next week.

Posted By: MR_P_BODY

Re: 950 HP on E85 - idle taking off - 05/06/10 07:01 PM

The rpm thing sounds like a vac leak... what jets
are you running... and yes the E-85 summer fuel doesnt
like to fire at 20*

Posted By: 69dart

Re: 950 HP on E85 - idle taking off - 05/06/10 07:09 PM

Thats what I thought at first too ...but it was fine during break in and dies as soon as you cover the carb with your hand. I may shoot some carb cleaner around the intake just to be sure. It acts like the thottle is hanging up but its not or it wants to keep running on the main jets rather than the idle circuit.

Posted By: MR_P_BODY

Re: 950 HP on E85 - idle taking off - 05/06/10 07:15 PM

Do you have control with the idle screws... if you
turn them in will it die

Posted By: jamesc

Re: 950 HP on E85 - idle taking off - 05/06/10 07:19 PM

carb's not icing is it?

Posted By: 440Jim

Re: 950 HP on E85 - idle taking off - 05/06/10 07:48 PM

Quote:

Anyway could the air bleeds be a factor? I haven't changed the air bleeds from the factory gas settings after using the Quick Fuel kit to switch to E85 last year.

I would be surprised to see the gasoline air bleeds working with an E85 conversion. I would think they would need to be smaller, especially the idle air bleeds.

Posted By: jamesc

Re: 950 HP on E85 - idle taking off - 05/06/10 07:58 PM

Quote:

I haven't changed the air bleeds from the factory gas settings after using the Quick Fuel kit to switch to E85 last year.

guess i should read the whole post before replying. as you mentioned i can't see gasoline calibration working with the e85 but have no experience with it.

Posted By: 69dart

Re: 950 HP on E85 - idle taking off - 05/06/10 07:58 PM

Jim I was searching last night and read your posts on the E85 forum about your 950 so I was going to go pick up the same air bleeds you were using and see if that helps. I know you drilled your own jets but what jets would your .129 hole be equal to - 90-something?

The idle screws are working - it doesn't do it all the time but a couple times I put it in neutral to clear it out and wouldn't return back to idle. I had to shut it off and refire it.

Thanks Again Guys!!

Posted By: slippery440

Re: 950 HP on E85 - idle taking off - 05/06/10 08:02 PM

Take some advice from someone that has been thru a carb shop that said he knew how to convert a carb to E85.He did not and the carb was total junk. Then I posted on here and was given a number of a guy that does E85 carbs. Air Bleeds and emulsion tubes and idle circuit all have to be done. Send me a PM if you want the number of the guy that fixed mine. Mine came back and ran almost dead on. All we are doing is a bigger jet size. He had mine done and back to me in 4 days and was very resonable on the redo.He almost had to start from scratch.

Posted By: 69dart

Re: 950 HP on E85 - idle taking off - 05/06/10 08:29 PM

I don't understand why the Quick Fuel kit doesn't mention the air bleeds need to be changed. Thank Goodness for that InterWeb machine.

I don't think it's a total re-do it runs pretty good - actually a little faster than gas - just like anything new a few quirks to work out.

Posted By: Hunted Duck

Re: 950 HP on E85 - idle taking off - 05/06/10 08:37 PM

An air bleed change isn't the only thing that needs changed. Your boosters need changed also.

Posted By: BobR

Re: 950 HP on E85 - idle taking off - 05/06/10 08:38 PM

Doubt if airbleeds-whether they be too large or too small- are causing it to idle too fast. How about your timing? Is your distributor locked out or do you still have the mechanical advance working? How about vacuum advance? I've seen cars idle good until revved then the timing advances and won't let the engine idle back down. As far as carb problems go a fast idle is almost always caused by excess air getting into the engine either through a vacuum leak or the throttle blade hanging open.

Posted By: 69dart

Re: 950 HP on E85 - idle taking off - 05/06/10 09:10 PM

It has a mechanical only advance Mallory Unilite distributor. I didn't take my light so I couldn't recheck the timing but I'm going to check that again.

I think the sticking throttle blade sounds most feasable - maybe the secondary is staying open just a bit.

I don't know about changing the boosters because then it wouldn't be easy to switch to gas if I ever needed to.

Posted By: MR_P_BODY

Re: 950 HP on E85 - idle taking off - 05/06/10 09:12 PM

Quote:

It has a mechanical only advance Mallory Unilite distributor. I didn't take my light so I couldn't recheck the timing but I'm going to check that again.

I think the sticking throttle blade sounds most feasable - maybe the secondary is staying open just a bit.

I don't know about changing the boosters because then it wouldn't be easy to switch to gas if I ever needed to.

Boosters are pretty east to change

Posted By: DemonDust

Re: 950 HP on E85 - idle taking off - 05/06/10 09:16 PM

Quote:

Quote:

It has a mechanical only advance Mallory Unilite distributor. I didn't take my light so I couldn't recheck the timing but I'm going to check that again.

I think the sticking throttle blade sounds most feasable - maybe the secondary is staying open just a bit.

I don't know about changing the boosters because then it wouldn't be easy to switch to gas if I ever needed to.

Boosters are pretty east to change

Don't you need a jig to change them? They are swedged in and once turned to alky can't be turned back to gas???? Thats what I was told anyway....

Posted By: 69dart

Re: 950 HP on E85 - idle taking off - 05/06/10 09:16 PM

Really I thought I read on the E85 forum you needed a special $265 tool to change them.

Posted By: MR_P_BODY

Re: 950 HP on E85 - idle taking off - 05/06/10 09:21 PM

Quote:

Quote:

Quote:

It has a mechanical only advance Mallory Unilite distributor. I didn't take my light so I couldn't recheck the timing but I'm going to check that again.

I think the sticking throttle blade sounds most feasable - maybe the secondary is staying open just a bit.

I don't know about changing the boosters because then it wouldn't be easy to switch to gas if I ever needed to.

Boosters are pretty east to change

Don't you need a jig to change them? They are swedged in and once turned to alky can't be turned back to gas???? Thats what I was told anyway....

Nope and nope... go onto Holley's web site they have
a step by step of booster change

Posted By: DemonDust

Re: 950 HP on E85 - idle taking off - 05/06/10 09:58 PM

Do you have a link Mr P??? I did a search and came up with 0 results...

Posted By: MR_P_BODY

Re: 950 HP on E85 - idle taking off - 05/06/10 10:02 PM

Quote:

Do you have a link Mr P??? I did a search and came up with 0 results...

No, not on this computer

Posted By: ajcasini

Re: 950 HP on E85 - idle taking off - 05/07/10 04:40 PM

Mr P I found the link you were talking about I think but its for 4500 dominator style boosters which are easy to change. I couldnt find anything on the 4150 carbs like he has. With the 4150's from my experience you need a special tool to swedge the boosters in place. if you have something for the 4150 please post it.

As far as the idle I would look at timing and possible throttle plate sticking open. I found a strange thing when I replaced the 4 hole gasket on my car. Used a Summit brand gasket and the gasket was actually hanging up the secondary throttle blades.

I would look for a vacuum leak around the intake as well. I have had that issue before.

As far as running better than gas you bet it will. You should be .1 or more faster than on gas. I picked up .3 and 4 MPH over 110 race gas on a 10.5 - 1 440.

I would change the air bleeds and set them up somewhere around 26-28 on the High Speed Bleed and 62 on the Idle Air bleed.

I changed the boosters in mine as I feared it would lean out too much on the top end with the smaller boosters.

Posted By: 69dart

Re: 950 HP on E85 - idle taking off - 05/07/10 05:58 PM

I picked up the air bleeds today same as Jim was using so we'll see if they help. I'm going to clean it out really well too because like I said we did drywall the garage and the car was covered in drywall dust. The engine was covered but you never know. I swapped to E85 last fall and didn't have the troubles then.

I keep an EGT in the car and kept an eye on the temp when dialing in the E85 - the temps were lower than gas so it should be getting enough juice. The 950 is probably a little big for my combo so that's probably why the boosters are ok.

Posted By: dbran451

Re: 950 HP on E85 - idle taking off - 05/07/10 08:25 PM

Quote:

Mr P I found the link you were talking about I think but its for 4500 dominator style boosters which are easy to change. I couldnt find anything on the 4150 carbs like he has. With the 4150's from my experience you need a special tool to swedge the boosters in place. if you have something for the 4150 please post it.

As far as the idle I would look at timing and possible throttle plate sticking open. I found a strange thing when I replaced the 4 hole gasket on my car. Used a Summit brand gasket and the gasket was actually hanging up the secondary throttle blades.

I would look for a vacuum leak around the intake as well. I have had that issue before.

As far as running better than gas you bet it will. You should be .1 or more faster than on gas. I picked up .3 and 4 MPH over 110 race gas on a 10.5 - 1 440.

I would change the air bleeds and set them up somewhere around 26-28 on the High Speed Bleed and 62 on the Idle Air bleed.

I changed the boosters in mine as I feared it would lean out too much on the top end with the smaller boosters.

can you post a link thanks

Posted By: cudadon

Re: 950 HP on E85 - idle taking off - 05/08/10 03:19 PM

Quote:

I know you drilled your own jets but what jets would your .129 hole be equal to - 90-something?
[/quote .129 hole size is close to holley #100 jets. Don

Posted By: 69dart

Re: 950 HP on E85 - idle taking off - 05/09/10 11:45 PM

After this weekend I'm pretty sure I have an intake leak. I usually use the paper gaskets on each side but I tried just the belly pan and RTV over the winter. So I'm going reseal the intake and give another try.

I'm still going to change the air bleeds.

Posted By: 69dart

Re: 950 HP on E85 - idle taking off - 05/16/10 12:47 AM

After a couple days of tuning it seems to be running much better. The idle problem has cleared up. Changing the air bleeds as suggested made a huge difference. The car drives around with better manners and pulls much better on the big end. I played with the timing backing it down to 33-34 from 36 and it killed a 1/10th. So I tried advancing the timing to 37-38 and it liked that alot. In today's heat the car ran a new season's best of 6.60 in the 1/8th at over 103. I haven't been able to run it out the back door because I keep tuning during elimations but that should be 10.44ish. Thats a decent gain from the 10.60's when I started.

Anyway no more tuning for now because tomorrow is the big race. Hopefully I can go some rounds when it matters!

Posted By: Leigh

Re: 950 HP on E85 - idle taking off - 05/16/10 12:54 AM

Quote:

Anyway no more tuning for now because tomorrow is the big race. Hopefully I can go some rounds when it matters!

Amen. Now sharpen up that shoe polish bottle, and go mow em' down.

Posted By: 440Jim

Re: 950 HP on E85 - idle taking off - 05/16/10 04:45 PM

Quote:

I picked up the air bleeds today same as Jim was using so we'll see if they help.

Quote:

The idle problem has cleared up. Changing the air bleeds as suggested made a huge difference. The car drives around with better manners and pulls much better on the big end.

So that seems better. I am looking forward to hearing the track results.

Getting enough fuel without changing the booster might be tough, but I ran mine that way all year (2008). E85 is pretty forgiving on A/F (within reason). I had Mark Sullens put larger flowing boosters in mine, but I haven't used the carb since the rebuild because I put the Ron's injection on.