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mo balls than $cents$
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Discussion Starter #1
we took out my uncle's blown injected 547 tx-20 yesterday and we're still having injection issues. i think it doesn't have enough fuel supply volume, he used smaller lines than recommended in the enderle instructions he got from good vibrations. it's a bitch to start, you've gotta prime the shit outta it, then once it's cranked up, you gotta stay popping the primer to keep it runnin till it begins the surge. once it's surging, it does fine till we hit wot, then it'd hook ass for 3seconds, go lean and die. i think it just doesn't have big enough fuel supply lines and the high speed bypass is returnin more than the small supply lines can keep up with.

what line sizes should the tank to 80a and 80a to meter block be? he's got 1/2 tank to pump line on it now, and the line from the pump to the meter block is even smaller. i think this is the issue but needed some other opinions. he had all stainless made up and i'm trying to get him to go get some cheap bigger 1's made up today to see if it solves the fuel starvation issue at wot.

appreciate any help fellas, i'm no mechanical injection guru, just learning the stuff myself and havig fun with it
 

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adjones419
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1,064 Posts
You're going lean at wide open throttle?! :))eek:))

I run a #16 line from the tank to my 110 pump (I think the #16 is pretty standard for the kind of power we're making), and a #8 line from the pump to the barrel valve.
 

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mo balls than $cents$
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Discussion Starter #3
You're going lean at wide open throttle?! :))eek:))

I run a #16 line from the tank to my 110 pump (I think the #16 is pretty standard for the kind of power we're making), and a #8 line from the pump to the barrel valve.
yep:)sphss we didn't keep pushing it, just done it twice to figure out wtf was happening, otherwise we'd be parts replacing trying to find it.

#16 =3/4in and #8 is 1/2 right? we're making up some ugly lines with 3/4 and 1/2 just to make sure it corrects it before ordering the high $$$$ lines.
 

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mo balls than $cents$
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Discussion Starter #5
Once it picks up fuel from the pump, how does it idle? What size main pill do you have in the barrel valve? Port lines and hat lines, or just hat lines?

AN Fitting Thread Size Chart
112, idle surges from 800 to 4200, idle surge is fine, he richened it up to surge the way it does using the link between the hat and block, which is the way the instructions show to do it.
 

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Premium Member
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6,008 Posts
Call Enderle and go back to their recommended baseline setup, start with changing all lines to what they specify and make sure your tanks are vented well.

Do you have an old line feeding the pump? It could be collapsing.
 

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mo balls than $cents$
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11,734 Posts
Discussion Starter #7
Call Enderle and go back to their recommended baseline setup, start with changing all lines to what they specify and make sure your tanks are vented well.
they don't specify return line size at all, that's what we're stuck on right now. it has a 3/4 feed line to the pump now and a 1/2 to the hat, 6an hoses from the highspeed bypass and idle bypass. the shutoff valve bypass is now loop lined back into the pump inlet using a enderle loop line kit. so we're returnin 2 6an lines to the tank, 1/2 from the tank to the 80a pump.
 

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Fuel pump

they don't specify return line size at all, that's what we're stuck on right now. it has a 3/4 feed line to the pump now and a 1/2 to the hat, 6an hoses from the highspeed bypass and idle bypass. the shutoff valve bypass is now loop lined back into the pump inlet using a enderle loop line kit. so we're returnin 2 6an lines to the tank, 1/2 from the tank to the 80a pump.
Call Jim at Enderle 805-526-3838 or Casey at Good Vibrations 800-576-7661. tell them your delema. Id say too small fuel pump for that motor! Has pump been flowed? know your pressure at 2k 4k? Also GORR in havasu sure one of these guys will get you going:)
 

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Bostick Racing Engines
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1,063 Posts
Is this blown gas or alky?

If gas, 80a pump should be fine... unless you are running a pile of boost.... then perhaps a 110-600 pump would be in order. I'd say a minimum of -12 feed to pump and -6 to the barrel valve and returns for 80a with gas.

If alky... you need a bigger pump... 80a just ain't gonna cut it... and -16 to fuel pump and -8 to barrel valve and returns.

Honestly... I wouldn't even attempt to play with a high-speed bypass untill you have the overall system functioning properly.

But... really the best advice would be to call the folks you got the system from and go over it with them.
 

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Canoe Jockey
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1,130 Posts
-8 to the injector....-6 returns from checks...-8 return from shut off...at least -10 on pump supply. Make sure the checks are installed the right way in the lines. Start with bv @ 27% with butters set .014. With that bv set so fat you will fill the oil pan up with carbon. GV has the schizmo on the fuel system. Also the system must be well vented
 

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Members only
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4,518 Posts
Couple of things come to mind. One is make sure the popets/check valves are not stuck open with dirt or other obstructions. I have had this happen before & can cause a lot of the said problems. Also not sure I would run regular hose on the pump supply for testing. It could colapse under a heavy load. A -12 line is good for the feed and its important to make sure the fuel pump is always in a wet condition. Meaning the fuel level in the tank supplying it is higher than the inlet to the pump. Start at the fuel tank & inspect the entire system 1 piece at a time. You will find the problem.:)
 

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Canoe Jockey
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1,130 Posts
I am just throwin this garbage out for info.. backfires when throttle opens or soft response...idle to lean, manifold air leak, main or secondary bypass stuck open or weak/ missing spring, too much ign avance, or a bent intake valve. also there is about 3 different 80a pumps. you must know the flow..
on a new enderle 80a-1 the pump is rated @ 6.8 gpm @ 4000 Pump rpm 100 psi
divide rpm by pump flow...4000/6.8 = 588.235
take the factor 588.235 to determine the flow @ any rpm

pump rpm
1000...1000/588.235 = 1.70 gpm
2000...2000/588.235 = 3.40 gpm
3000...3000/588.235 = 5.10 gpm
4000...4000/588.235 = 6.80 gpm

mechanical pumps are linear
 

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No Sandbar To Far
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3,276 Posts
This thread was started two years ago. :wtf:
 

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Canoe Jockey
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LOL....when ya get old you lose track of time...what day is it??
 

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Thread jack

So how about some opinions on using alky mechanical injection on 8-71/10-71 blower
for a boat that does not always get used at full throttle. What are the potential problems?
Maybe its just safer to spend the extra 3k and get EFI unit to avoid carbs.
 
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