Correct SU Fuel pump for a BJ8 [ PSI specs] ?

[Ed_K]

Hello all,

I was researching to find the correct SU fuel pump for my 65 BJ8
and discovered that SU makes two different pressure rated fuel
pumps ;

AZX1307 = 16 GPH @ 2.7 PSI
AZX1308 = 16 GPH @ 3.8 PSI

The SU web site says the AZX1308 is the one and only correct SU
fuel pump that they make for the 65 Austin Healey 3000.

.....

I checked the last electronic version of the SU that I received from our usuall parts supplier and discovered that
they had sent me a AZX1307 ( en ) which is the wrong pump per the SU web site ?

I suspect that this 1.1 PSI difference was designed for a good reason or SU would simply list one pump for all 2.7 - 3.8 applications ?

Does anyone on the forum know for certain that we need the 3.8 PSI rated pumps ?

Thanks,
Ed K.

 

[Chilly]

I just checked my box of parts. they sent me a AZX1318 (ELECTRONIC) ??? '66 BJ8.

the website says it's for a MG ??

looks like another phone call :frown:

 

[Ed_K]

Here is a link to the various SU fuel pump specifications that I found on the web. Just click on " full screen " to read the chart...
https://www.docstoc.com/docs/68733327/Fuel-pump-specs

and here is a link to SU's web site ...

https://www.sucarb.co.uk/ProductCategory.aspx?ParentId=16&C=151

Chilly,
It appears that our usual supplier is always sending out the 2.7 PSI version of the SU fuel pump when the 3.8 PSI version is what is called for per the SU web site ?

I wonder what is going on with this ?

Ed

 

[Chilly]

i'm ok with lower pressure. On other cars, I've found too high is an issue. this SU stuff is new to me. even though I worked at a beck arnley parts store many years ago :crazy:

it looks like the 1318 is not polarity sensitive. so I should be ok.

Thanks for the Links, Will

 

[Deleted member 8987]

https://www.myaustinhealey.com/austin_healey_technical_articles.html
"Delivery pressure for either SU's or Webers should be in the 3.5 preferred - 4 max lbs per square inch range - unless you have made major mods to the carbs themselves."
Ref AZX1331. Fit near tank, 12 volt, 15 galls/hour at 2.7 p.s.i. As fitted to
MGA, Austin Healey 100 four cylinder

Apparently the 2.7 PSI is for a 100-4?

 

[Chilly]

I might be looking at this wrong. if it flows 15GPH that should be good.

 

[Ed_K]

That article certainly points at the need for 3.8 PSI pump fuel pressure just like the SU web site lists only 3.8 PSI pumps for an Austin Healey 3000.

I am certain that SU would not go to the trouble to make two different pumps with the only difference being in the PSI rating if it did not matter !

Then why is our usual supplier sending out the 2.7 PSI rated pumps for our cars when SU lists only the 3.8 PSI pump for the 65 3000 ?

I guess I will have to ask them why they apparently are doing this by design, ( not a mistake since they send out more than one pump for a BJ8 at the lower than recommended PSI rating ).

Ed

 

[Ed_K]

I called Moss and the guy that answered didn't know but referred me to Michael Grant 805-681-3411 . I left a message with the question.
I'll report back when I get the answer.

Ed K.

 

[Keoke]

it looks like the 1318 is not polarity sensitive. so I should be ok.

You will be OK with this " 1318 " Electronic pump if your car is Positive ground.

the SU pump is flow rate sensitive either the 1307 or 1308 style punmps will work on the later cars as they have the same flow rates.--Keoke

 

[Ed_K]

The Moss guy said that as long as the flow (GPH) was enough and the pressure did not exceed
7-10 lbs that it would work ok. They have had no complaints about low pressure.

He had no idea why SU made two different specifications ( 2.7 or 3.8 ) PSI pumps and only the 3.7
was listed for the Austin Healey 3000.

Interestingly enough, Moss's double ended SU they sell for an Austin Healey 3000 is
listed as a 3.2 PSI pump. The SU web site says this pump is no longer available and is
replaced by a double ended 3.7 PSI pump.

Ed