Need some help

September 21, 2020, 03:02 PM

TOP38

quote:
Originally posted by CHampshire:
quote:
Originally posted by TOP38:
I don't think its converter related. My guess is fuel also. Have you checked your floats? Alky is not kind to them. Brass floats can collapse and the black ones can become alky soaked messing with the fuel level in the bowls, check those. If you have O2 logged you know right away if it was fuel related.

Also have you noticed it using more fuel on a run now vs at the start of this swap, this would be another indication you got float bowl issues. Alky can run fine even when it's pig rich unlike gas...

No o2 unfortunately. Thanks for the info on the floats. They are the black ones. They were new with the carb and have 50 passes on them. As far as fuel useage, we used 5 gallons yesterday on two warm ups, two time runs and first round. That doesn't seem like a lot to me, but I am new to alky so I don't know for sure. It's a lot compared to race gas though!

Sounds high to me,,, warmups need a lean out valve or even a primer plus system that allows you to warm up on gas and also just before you put it away for the day.

With the car idling slowing increase rpm and note at what rpm the boosters begin to flow fuel. High floats will start flowing fuel much earlier than normal and you will use much more fuel than you should.

If you carb is relatively new, your floats are likely ok. What normally occurs is as the floats become heavier due to fuel soak, the fuel level rises in the bowls, without knowing, racers readjust the floats, this reduces float drop which restricts fuel flow at WOT which causes a lean condition to occur.

September 21, 2020, 03:07 PM

CHampshire

quote:
Originally posted by Mike Rietow:
Have you got a engine rpm graph from before you changed the bypass pressure, you can post? Any difference in that graph?

Mike,

No graph handy on the bypass pressure change. We changed it in the pits yesterday between 2nd TT and First round. Car ran the same et... I have the graphs at home just not with me. That said apples to apples it was the same.

September 21, 2020, 03:08 PM

rusty

that fuel system will not run my alky setup,i did try it before going back to a belt drive system

September 21, 2020, 03:13 PM

CHampshire

quote:
Originally posted by TOP38:

Sounds high to me,,, warmups need a lean out valve or even a primer plus system that allows you to warm up on gas and also just before you put it away for the day.

With the car idling slowing increase rpm and note at what rpm the boosters begin to flow fuel. High floats will start flowing fuel much earlier than normal and you will use much more fuel than you should.

If you carb is relatively new, your floats are likely ok. What normally occurs is as the floats become heavier due to fuel soak, the fuel level rises in the bowls, without knowing, racers readjust the floats, this reduces float drop which restricts fuel flow at WOT which causes a lean condition to occur.

On the fuel usage thing we have the lean out plumbed with 1/4" line. I am getting the stuff to change it over to 1/2" line for this weekend as 1/4" it won't even speed the engine up with it open.

We did check the float levels at the track and they didn't raise any red flags. the back was a bit high and front was right on. It's easy enough to pull the float bowls and check them out though!

September 21, 2020, 03:15 PM

CHampshire

quote:
Originally posted by rusty:
that fuel system will not run my alky setup,i did try it before going back to a belt drive system

How fast were you running at the time? I do feel like the car should run faster than it does even when running good, but I also see guys running an Aeromotive setup going 4.60's with an electric pump. I am torn on this.

September 21, 2020, 03:20 PM

TOP38

The air bleed lean out deal works but if it raise the rpm high enough to start fuel flowing from the boosters your defeating the goal.

With alky, you need to put the motor away hot, especially in the spring and fall, akly attracts water and if the car sits for any time it will rust the cylinders, more of an issue with a rich cool running motor also. The Primer Plus deal works great to eliminate this issue along with cool morning start ups. You will like save the cost of it in alky is a short period.

September 21, 2020, 03:53 PM

JPosey

It has a bad fuel line/fitting on it. Which one? I have no idea.

You got a bad fuel line Corey. I have no clue which one.[/QUOTE] Mike, what do you think is happening to the lines? Collapsing under vacuum? Just curious, I have seen that a lot in hydraulic systems and fuel could possibly do same thing.

September 21, 2020, 03:56 PM

Mike Rietow

quote:
Originally posted by TOP38:
The air bleed lean out deal works but if it raise the rpm high enough to start fuel flowing from the boosters your defeating the goal.

Very true, unfortunately mostly only those who have been demonstrated the phenomenon your speaking of, will follow this point.

The lean out can trash the oil wash the bearings if not used properly. I've seen it.

September 21, 2020, 08:42 PM

rusty

quote:
posted September 21, 2020 03:15 PM Hide Post
quote:
Originally posted by rusty:
that fuel system will not run my alky setup,i did try it before going back to a belt drive system

i cant recall with the electric pump ,but after low 4.5s to high 40s
How fast were you running at the time? I do feel like the car should run faster than it does even when running good, but I also see guys running an Aeromotive setup going 4.60's with an electric pump. I am torn on this.

September 22, 2020, 05:14 AM

ts393c

quote:
Originally posted by CHampshire:
quote:
Originally posted by ts393c:
I will say 8 pounds of pressure is a lot. Every time I ran that much it would blow the bowls over.

How much do you run on alky with an electric pump?

I never ran more than 7 pounds. Even when I had my dragster with a 582 running 4.60 I ran 7 pounds. I do think belt drive systems are better.

September 22, 2020, 08:07 AM

CHampshire

Thanks everyone for the feedback. I have an update...well sort of. At the start of the season, a few races in we had a fuel pump issue. Long story short we were aerating our fuel and had to change our return line in the tank.

When we put it back together we added a fitting to the bottom of the regulator to check pump bypass pressure. In doing so we may have created this issue. The line from the pump to the regulator has a nice twist to it now. See the photo below.

We think this may be our culprit and will be re-plumbing this to see. We are most likely going to be changing the lines out of the regulator to the carb as well, mainly for piece of mind.

What do you guys think? Smoking gun?

September 22, 2020, 08:31 AM

Mike Rietow

quote:
Originally posted by CHampshire:
Thanks everyone for the feedback. I have an update...well sort of. At the start of the season, a few races in we had a fuel pump issue. Long story short we were aerating our fuel and had to change our return line in the tank.

When we put it back together we added a fitting to the bottom of the regulator to check pump bypass pressure. In doing so we may have created this issue. The line from the pump to the regulator has a nice twist to it now. See the photo below.

We think this may be our culprit and will be re-plumbing this to see. We are most likely going to be changing the lines out of the regulator to the carb as well, mainly for piece of mind.

What do you guys think? Smoking gun?

Yep, new hose AND new Russell fittings. You're half way there on the Russell fittings looks like (have a few already).

September 22, 2020, 08:44 AM

Mike Rietow

I wouldn't F around with it. Nothing worse than burning fuel for nothing.

This (below) is burning fuel for nothing

October 12, 2020, 07:40 PM

CHampshire

Update on this. First off, thanks to everyone that pitched in and gave me some suggestions. Here is what we did.

Took the Magna fuel stuff off, and went to APD. Bought a belt drive pump, fuel log, regulator and gear for the crank mandrel. Re-plumbed per their instructions. Set fuel pressure per their instructions. Hauled butt. Car went from 4.98 at 136 last time out to 4.90 at 141 yesterday. Here are some photos for reference.

Very pleased with the results for now. Water temp didn't climb during the run either. What it was staged at was what it was when it got back to the trailer. Hardly ran the fan at all.

I still think it should be going faster with that mph. We will be borrowing a convertor from a friend for the coming weekend and making some shock changes as well. Will see if we can get it into the low 4.80's before the end of the year.

October 12, 2020, 07:51 PM

Mike Rietow

quote:
Originally posted by CHampshire:
Update on this. First off, thanks to everyone that pitched in and gave me some suggestions. Here is what we did.

Took the Magna fuel stuff off, and went to APD. Bought a belt drive pump, fuel log, regulator and gear for the crank mandrel. Re-plumbed per their instructions. Set fuel pressure per their instructions. Hauled butt. Car went from 4.98 at 136 last time out to 4.90 at 141 yesterday. Here are some photos for reference.

Very pleased with the results for now. Water temp didn't climb during the run either. What it was staged at was what it was when it got back to the trailer. Hardly ran the fan at all.

I still think it should be going faster with that mph. We will be borrowing a convertor from a friend for the coming weekend and making some shock changes as well. Will see if we can get it into the low 4.80's before the end of the year.

Good deal

Gold piggy back canisters, with separating piston inside still, LMP?

October 12, 2020, 11:04 PM

smokinjeff

Take belt off vaccum pump and listen for the vanes clicking as you spin it. If not you may have some stuck vanes and that will slow you down. Just something to check and rule out.

October 13, 2020, 12:32 AM

Don Higgins Crew Chief Pro Software

Your weather station is broken as well, it is not possible to have barometric pressure over 30.30 unless you are racing under the ocean. For reference, 29.92 is sea level.

I would not run alcohol with an electric pump either, glad you changed it.

October 13, 2020, 05:18 AM

CHampshire

Mike,

It has Penske doubles on the back. Qa1 on the front suspension (Diamond double suspended car). When we bought the car, the other guy had a 632 in it with an aluminum block. We have never turned a knob on any of the dampers. I'm sure it needs tweaking!

Jeff,
We will check out the vacuum pump for sure. Good idea and something that is easy to check and easy to over look.

Don,
I am pretty sure you are probably right. I am using a TAG hand held from the 90's. First gen to boot. Have had it forever. One of these days we will update to a trailer unit like you sell. Thanks for the feedback! I appreciate it!