10mm A or 13 mm rotary April 26, 2024 06:51AM
Going into a class that allows 10mm A pump or an 13mm rotary. Obviously, the rotary is more expensive but outside of that what is the better option. A pump will do 550 CC
rotary 625 CC. Won't need that much fuel either way so what's the pros a cons.

Thanks.
Reply Quote

Re: 10mm A or 13 mm rotary April 28, 2024 01:41AM
Bump
Reply Quote

Re: 10mm A or 13 mm rotary April 28, 2024 02:37AM
I'm not an A pump fan. However I would likely lean towards it from a cost point. However I believe the rotary would out perform the A pump. I've seen this time and again. Just my penny's.
Reply Quote

Re: 10mm A or 13 mm rotary April 29, 2024 01:21AM
Quote
Old timer
I'm not an A pump fan. However I would likely lean towards it from a cost point. However I believe the rotary would out perform the A pump. I've seen this time and again. Just my penny's.

Well.... no A rotary has one plunger versus the inline that has six, there is no comparison of fuel delivery especially at high RPMs. I have seen countless AMBACs seize the heads, no fun.
Reply Quote

Re: 10mm A or 13 mm rotary April 29, 2024 05:01AM
Quote
?

I'm not an A pump fan. However I would likely lean towards it from a cost point. However I believe the rotary would out perform the A pump. I've seen this time and again. Just my penny's.

Well.... no A rotary has one plunger versus the inline that has six, there is no comparison of fuel delivery especially at high RPMs. I have seen countless AMBACs seize the heads, no fun.

You have seen countless seized heads because A. The pump wasn't built right, or B. Not running enough lube in the fuel. Or C. The pump feeding the ambac is insufficient. As far as fuel delivery a good properly built 13mm Ambac will kick the brown stuff out of a 10mm A pump. No matter how you slice it a 13 mm plunger driven by the correct cam ring will delivery way more fuel than a 10mm plunger. All 6 of your 10mm plungers only plunge 1 cylinder at a time sir.
Reply Quote

Re: 10mm A or 13 mm rotary April 30, 2024 02:14AM
Quote
Old Timer


I'm not an A pump fan. However I would likely lean towards it from a cost point. However I believe the rotary would out perform the A pump. I've seen this time and again. Just my penny's.

Well.... no A rotary has one plunger versus the inline that has six, there is no comparison of fuel delivery especially at high RPMs. I have seen countless AMBACs seize the heads, no fun.

You have seen countless seized heads because A. The pump wasn't built right, or B. Not running enough lube in the fuel. Or C. The pump feeding the ambac is insufficient. As far as fuel delivery a good properly built 13mm Ambac will kick the brown stuff out of a 10mm A pump. No matter how you slice it a 13 mm plunger driven by the correct cam ring will delivery way more fuel than a 10mm plunger. All 6 of your 10mm plungers only plunge 1 cylinder at a time sir.

The heads seize because the pump is being pushed to the limit because it only has one plunger ratcheting around with insufficient fill time. An inline with its six plungers all filled to the brink with fuel ready to go dont have this issue.

13 mil AMBAC 640cc 13 mill A pump 1100 cc
Reply Quote

Re: 10mm A or 13 mm rotary April 30, 2024 03:38PM
Quote
Whoa Nelly



I'm not an A pump fan. However I would likely lean towards it from a cost point. However I believe the rotary would out perform the A pump. I've seen this time and again. Just my penny's.

Well.... no A rotary has one plunger versus the inline that has six, there is no comparison of fuel delivery especially at high RPMs. I have seen countless AMBACs seize the heads, no fun.

You have seen countless seized heads because A. The pump wasn't built right, or B. Not running enough lube in the fuel. Or C. The pump feeding the ambac is insufficient. As far as fuel delivery a good properly built 13mm Ambac will kick the brown stuff out of a 10mm A pump. No matter how you slice it a 13 mm plunger driven by the correct cam ring will delivery way more fuel than a 10mm plunger. All 6 of your 10mm plungers only plunge 1 cylinder at a time sir.

The heads seize because the pump is being pushed to the limit because it only has one plunger ratcheting around with insufficient fill time. An inline with its six plungers all filled to the brink with fuel ready to go dont have this issue.

13 mil AMBAC 640cc 13 mill A pump 1100 cc

Whoa Nelly, apparently you missed the part where I mentioned sufficient fuel supply pump and apparently you missed the part in opening post where That guy was comparing a 10mm A pump capable of 550cc to an Ambac 13mm capable of 625ccs. I really don't give 2 hoots either way, because there is better pumps available than either of these 2. Just sayin.
Reply Quote

Re: 10mm A or 13 mm rotary May 01, 2024 12:41AM
Quote
Old timer




I'm not an A pump fan. However I would likely lean towards it from a cost point. However I believe the rotary would out perform the A pump. I've seen this time and again. Just my penny's.

Well.... no A rotary has one plunger versus the inline that has six, there is no comparison of fuel delivery especially at high RPMs. I have seen countless AMBACs seize the heads, no fun.

You have seen countless seized heads because A. The pump wasn't built right, or B. Not running enough lube in the fuel. Or C. The pump feeding the ambac is insufficient. As far as fuel delivery a good properly built 13mm Ambac will kick the brown stuff out of a 10mm A pump. No matter how you slice it a 13 mm plunger driven by the correct cam ring will delivery way more fuel than a 10mm plunger. All 6 of your 10mm plungers only plunge 1 cylinder at a time sir.

The heads seize because the pump is being pushed to the limit because it only has one plunger ratcheting around with insufficient fill time. An inline with its six plungers all filled to the brink with fuel ready to go dont have this issue.

13 mil AMBAC 640cc 13 mill A pump 1100 cc

Whoa Nelly, apparently you missed the part where I mentioned sufficient fuel supply pump and apparently you missed the part in opening post where That guy was comparing a 10mm A pump capable of 550cc to an Ambac 13mm capable of 625ccs. I really don't give 2 hoots either way, because there is better pumps available than either of these 2. Just sayin.

A belt driven pump putting out 100 to 150 psi is not sufficient????? The class near me making the red guys run the AMBAC is dying, no one wants to run that pump anymore.

What is better then an inline A other then the P? The stock AMBACS have a bad rep as well, I had to replace the head twice on one with 8000 hrs total on it, I am not the only one .
Reply Quote

Newer Topic Older Topic

Author:

Your Email:


Subject:
Spam prevention:
Please, enter the code that you see below in the input field. This is for blocking bots that try to post this form automatically. If the code is hard to read, then just try to guess it right. If you enter the wrong code, a new image is created and you get another chance to enter it right.
Message:
Website Statistics
Global: Topics: 38,717, Posts: 229,825, Members: 3,330.
This forum: Topics: 37,083, Posts: 225,961.

Our newest member LT Limited Pro