I just got a Carter M4889 Strip Super pump and I'm a little concerned about the size of the inlet and outlet holes. They are 1/4" Pipe and I am planning on upgrading to 8AN lines tank to pump and 6AN pump to carb. The Carter has smaller holes than my stock replacement pump. I want to know if I should send the new Carter back and get a Holley of other high flow pump with larger fittings or is the Carter enough pump even with the 8AN to 1/4" pipe reduction? I really dont want to lean this engine out and have a melt down, My only track outing with this combo had a top end lean and I dont want that

Thanks

That is a better pump than most realize. It fed my 640 horse 496 to ~ 11 flat 1/4 mile while still holding ~ 5.5 psi. That was with 1/2" fuel line from the tank forward.

I have since changed out to a Carter 172. The Carter 172 needs -10 line from the tank forward to meet its 172 GPH potential. The use of -8 line from the tank forward puts the 172 closer to the 4889 pump in GPH.

You could use -6 from the pump to the carb, but I think -8 would be better.

Thomas

Carter 172 (http://store.summitracing.com/default.asp?target=esearch.asp&N=100&Ntk=PartSearch&Ntt=crt-m61045)

I've always wondered why they put those little 1/4" outlets on those pumps, :confused: .

Originally posted by Bomber '67:
That is a better pump than most realize. It fed my 640 horse 496 to ~ 11 flat 1/4 mile while still holding ~ 5.5 psi. That was with 1/2" fuel line from the tank forward.

I have since changed out to a Carter 172. The Carter 172 needs -10 line from the tank forward to meet its 172 GPH potential. The use of -8 line from the tank forward puts the 172 closer to the 4889 pump in GPH.

You could use -6 from the pump to the carb, but I think -8 would be better.

Thomas I have a 3/8" line from the tank to the front of the car, and an 8an from the 3/8 line to the pump on my Carter 172.

it feeds my engine to, so far, 117.31 mph, 6100rpms.

I have a couple of good used 172 pumps for sale.

using the malloy 140 now?

Originally posted by Motor Martyr:
using the malloy 140 now? Not on purpose Brian. Fuel pump pushrod problem possibly left my lobe scored, so I am forced to use an electric at this point. Over winter I may pull cam and see what's up. Being involved in points racing this year, I do not want to change anything..

i think the 140 will be fine solo. To be quite honest if i were to do it again i'd opt for the mallory 140 instead of the mechanical, since it makes setting the float levels an easy task.

Originally posted by Motor Martyr:
i think the 140 will be fine solo. :confused:

It's a matter of simplicity - "Find the simplest way to accomplish a task utilizing the least amount of resources to minimize your exposure to failure"

I will be going back to a mechanical pump as soon as it is feasible (pull cam out)

Originally posted by Motor Martyr:
i think the 140 will be fine solo. To be quite honest if i were to do it again i'd opt for the mallory 140 instead of the mechanical, since it makes setting the float levels an easy task. You are kidding right!? come on BRIAN!!

Brian, if you are running a 3/8" line instead of the -10 that helps the Carter 172 get its GPH rating, then you would run just as fine with the regular Carter strip pump. Any advertising hype aside, if you disassemble a Strip pump and the 172 you will find everything the same - except the inlet/outlet plate.

Damn good running Camaro BTW.

Thomas

P.S. Guys, Brian holds some ideas that seem to work best for him, why not let it be at that?

thanks!

I did not know that about the two pumps, good stuff.

So you guys are necking down your fittings to the 1/4" inlet/outlet? Doesn't this sort of defeat the purpose of running 1/2" and/or 3/8" line?

Mark, the thing to keep in mind is that the "restriction" of flow is both a factor of: length and diameter. A restriction that is very short in length with have minimal impact on actual flow volume. What a lot of people fail to realize when doing any sort of automotive plumbing is that turns and bends are flow restrictions too. A lot of guys realize this on their exhaust, but then go on to kink up their fuel lines without much thought.

Thomas

Thomas(or anyone),

Do you think the same would be true if one kept a stock sending unit, which had 5/16" exit port, up-sized it to 1/2" line to run the length of the carb, then ran it to this pump, this downsizing it again. Then to to carb? On say a 500hp or so engine?

Anyone done such a thing?

My "stock" sending unit has a 3/8" line, its the stock unit for a high performance motor. I replaced the original 6 cylinder 5/16 line with this one.

Use common sense when building the fuel system, you dont need a Fire Hose to feed 4 .090" orifaces, nore do you need 500gph for a single carb Gas setup on a street strip car.

My suggestion use a line thats a resonable size for what you're doing, an adequate fuel pump, and be smart with fittings. Use fittings that have a full sweep, rather then a sharp turn, and dont kink up the fuel line when bending it!