More Power?

[wsa111]

I would not only install an electric pump, but replace the mechanical pump with a carter.

The carters normally push out 5-6# of pressure.

Gene you could install the carter this week, race & then install the electric if needed the following week.

I hate to see you run with the weak pump you have. Bill

 

[FalconSedanDelivery]

I see what your saying WSA , BUT , many times it the supply not the pump , the small line from the tank may be restricting enough that no matter what pump he puts in the stock local , it may not be enough , the small elec will help regardless is my point , , I use a Holley Blue with reg , and a 1/2 line from tank to carb then regulator to #6 AN That works great , BUT its Noisy as hell , LOL

 

[wsa111]

Don't you think a 3/8" line including a sender in the tank with the holley blue pump & regulator would do the job & elimimate the mechanical pump.
The big problem with a mechanical pump is that it maintains fuel pressure even with the engine shut off till it bleeds down. This can lead to carb flooding if the float & needle & seat can't control the pressure especially during heat soak conditions.

A quality mechanical pump with 3/8 line would probably also do the job. Its a tossup.

Remembler your fuel supply is only as good as its weakest part. Bill

 

[FalconSedanDelivery]

Oh Yeah That would do fine , , But its a bit loud ,

 

[Gene Fiore]

Actually now that I was looking on-line at Carter mech pumps I think the pump I have may actually be a Carter. The part# from my NAPA receipt is M6399 which is what I am finding as the part# on-line for the Carter pump. I suppose it could be a knock off by some off brand but wouldn't the part#'s be different? Anyway I like the idea of running an inline electric pump in conjunction with the mech pump with a toggle switch. Then I wouldn't care how loud the pump was since I would just use it when I am at the track. I have had a Holley blue pump before and it was loud as hell. Not something I want to run on my street/strip car.

 

[wsa111]

Gene, call Alex Denysenko @ moneymaker racing 219-861-1214.

He will advise you which pump to use & his prices are very good, plus he is a racer himself.

He normally carries everything in stock & can ship fast. Bill

 

[Gene Fiore]

163000
PRIMARY/SECONDARY
ROAD COURSE RACING, OFFSHORE RACING
AND STREET/STRIP APPLICATIONS
http://www.braswell.com/products/floats_1.htm
This is a float from braswell racing which is far better than the holley float.
They are avaiable from braswell & bo laws racing BLP.

This float i have found to be better than the stock holley float. Bill

What does this float achieve versus the stock Holley float?

 

[wsa111]

Gene, if your holley has the nitrophyl float in it the braswell has more leverage to help seal the needle & seat especially during heat soak conditions. It also provides better fuel control turning or cornering.

It performs better than the heavy brass float on all of the above. Bill

 

[Gene Fiore]

Remembler your fuel supply is only as good as its weakest part. Bill

Didn't race last weekend due to rain...I know I live in AZ and it rains...what the heck? Anyway I decided first things first. Let's make sure the system has no obvious weak points. On closer inspection I was pleased to find out that the steel fuel line running from the tank into the engine bay is already 3/8 inch...COOL! I decided to change the 1 1/2 year old fuel filter and hoses between the tank and pump just to feel warm and fuzzy. I did that and there was no change in the fuel pressure...I didn't really think it would make a difference but now I know for sure. This weekend I am going to drop the sending unit from the gas tank to inspect the senders fuel filter...I have never had it out since I bought the car 6 years ago... If this results in a dead end and I still have the weak fuel pressure I can concentrate on a solution. I have been looking on-line at electric pumps but my dilemna is this. Should I try to find one that has a max psi of about 6lbs so I don't need a regulator? What if it doesn't perform at it's stated max psi? Or should I go with a pump with a higher max psi rating and install a regulator? I like the Carter pumps because so far they are the only ones that come with all the parts needed for installation...nuts, bolts, ground strap, rubber grommets, bracket, fuel line fittings...everything except a regulator. Any ideas which way I should go if I need to go electric? Thanks.

 

[FalconSedanDelivery]

Its always better to run a regulator, that way if you get a pump that says 6 and actually puts out more its an easy fix , NEVER rely on the mfg's rating , KNOW what it does / is , saves lots of time trying to figure something out when a problem comes up ( quick elimination saves time ) , really why do it twice ? also make sure you have a extra o ring ( square O ring ) in hand before taking out your sending unit , because the moment its out it will expand , and unless you can wait a day or so , you WON'T get it back in place

 

[tri-power 250]

Gene, I just bought and installed a Summit Racing regulator plus gauge on my 250 with a stock mechanical fuel pump. My gauge read 6.5 psi,which I reduced to 5.5 psi. Is your mechanical pump just worn out? I am running 7/16 rubber fuel lines and a Fram clear fuel filter.
Good luck with your 14 second run.
Ken

 

[Gene Fiore]

Gene, I just bought and installed a Summit Racing regulator plus gauge on my 250 with a stock mechanical fuel pump. My gauge read 6.5 psi,which I reduced to 5.5 psi. Is your mechanical pump just worn out? I am running 7/16 rubber fuel lines and a Fram clear fuel filter.
Good luck with your 14 second run.
Ken

Really!! So you are saying that your oem mechanical pump was putting out 6.5 psi??? My pump is only 1 year old. What pump are you running? Pics of your setup would be nice!!

 

[Gene Fiore]

I am running 7/16 rubber fuel lines

You meant 5/16 fuel lines right? That would be from the pump to the carb...but your Mav should have 3/8 from the tank to the pump...assuming it is a 1971 or later MaV....RIGHT?

 

[tri-power 250]

Yes you are correct, 5/16th from pump to carb. I have not played with the fuel line size from the tank to the pump. A while back I did replace the rubber connections in the fuel line, they were all cracked from age.

 

[Gene Fiore]

So what pump do you have?

 

[tri-power 250]

I drove the car today for an hour or so, then rechecked the pressure, the new reading was 4.5 psi. The car ran great, remember, I do not spin the engine up, the rod bearing are getting ready to be replaced. The pump is what ever O'riellys sells.

Ken

 

[Gene Fiore]

Well, I went to the track today to see what the cooler temps would bring. The temps were in the low 60's today. I have not done anything regarding the low fuel pressure issue because I can't really decide what I want to do. Regardless, I did set a new personal best et of 15.21 at 82.8 mph...fuel pressure is constant at 3psi going down the track but it feels good the whole way down. Plus I went 3 rounds but ended up losing in the semi-finals.

 

[Invectivus]

Say Gene, how much did your shop charge for the knife edging on your crank?

 

[Gene Fiore]

Say Gene, how much did your shop charge for the knife edging on your crank?

$50.00

 

[FalconSedanDelivery]

Well Like I said before , I don't think your running out of fuel ( yet ) , BUT then I ran your mph through the calculator , and its a NO go , in other words your ET is PERFECT for your MPH , THAT means your laying down on top , and Fuel pressure would be my first change!, NO street car is that close usually 1/4-1/2 second off is the norm , nuff said