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Discussion Starter · #1 ·
So I finally hooked up a fuel pressure gauge and measured 8.5 psi and automatically thought this was too high. Everything I've read says 7 psi max but back in the day many TC'ers ran this pump just fine without a regulator. So I pulled up a spec sheet and it's an 8.5 psi pump. Also the comparable Holley pump is rated at 8psi. So what gives? I'm assuming as long as the needle and seat is not overpowered and you can set floats it's all good?
 

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Yup. Same here. I am about to swap to a new "street" pump. I bet it doesnt push 8.5.

Ray, where can I get a rebuild kit? I can't even find a darn # on the pump. The new street pump has 1/4 NPT in not 3/8 NPT as the old "172 NASCAR" pump. So while they look the same, I don;t think they are. I see the [email protected] Summit but nothing else.
 

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Discussion Starter · #5 ·
I would say you are right. Decades ago mechanical rarely used a regulator. If you keep an eye on plugs and float level you could be fine. I looked for one of those pumps in any condition for about 2 years with no luck. There is a guy that makes rebuild kits for them and most others.
I found this one on eBay NOS. So I guess the old 7 psi max preferably 6 is not valid.
 

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Discussion Starter · #7 ·

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If anyone knows where to get a refresh kit Ill buy asap.

Spent the time to polish it and a few bux having some nice 1/2" stainless lines made for it.
Really hate to have to do it all over again.

Speedway had one in stock last yr I shoulda just bought the darn thing.
 

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I think the part # is M61045, (obsolute) 175 free flow at 5-6.5 psi. No regulator needed. Mechanical pump flow is 50% of free flow at 6 psi.
Rebuild kit - Antique Auto, phone # 781-335-8860. He is in Boston. Hope this works.
Carter M4889 , 120 gph free flow, 7-8.5 psi. Regulator needed.
This is 2018 info.
 

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Interesting though it does say a regulator is required. Wonder how the 130/172 difference would come into play?
that holley 130gph pump says 7.5-9lns shutoff, regulator required?
I ran it without a regulator. 3/8 line from the tank, 3/8 line from pump to carb with inline filter. Not saying the specific pump you get may not be in the high side. I did leave the sintered bronze filters in the carb inlets which also act to cut down inlet pressure.

FYI, was running 126-127 through the traps feeding a 540" through a modified 4781 850.
Prior, I used the 110GPH version (12-454-11) to feed a 454" through same carb to 115-116 with no signs of lean out.
 

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Discussion Starter · #18 ·
I ran it without a regulator. 3/8 line from the tank, 3/8 line from pump to carb with inline filter. Not saying the specific pump you get may not be in the high side. I did leave the sintered bronze filters in the carb inlets which also act to cut down inlet pressure.

FYI, was running 126-127 through the traps feeding a 540" through a modified 4781 850.
Prior, I used the 110GPH version (12-454-11) to feed a 454" through same carb to 115-116 with no signs of lean out.
That's impressive and good to know!
 

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I ran the Carter M4889 for a while on my 540 and it put out a steady 7 psi. It wasn't enough for my motor so I upgraded it to the Carter M7901G pump which is their Billet aluminum pump and it fits the bill for my combo. The M7901G puts out 6 PSI. It's fed from 1/2'' stainless hard line and pick up from the tank to the pump, and 1/2'' stainless from the pump to both inlets on the carburetor. Its pricey, but its a great pump. Everyone hates it because it's anodized blue. I could care less, as long as it works.
 
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