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High base pressure and E85 users...how are you setup?

Old Apr 29, 2010 | 12:54 PM
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From: Chi -> Maidstone
High base pressure and E85 users...how are you setup?

So I noticed a few owners here running high base pressures for their E85 setups. But what I don't recall seeing is what they're doing with the FPR. Are you guys running a straight pressure across the board or still have the vac. line hooked up?

For example, 80 psi base on 6x1000cc ID injectors. Obviously 20 psi of boost will be 100 psi of fuel. Since there are those that are running more than that in terms of boost, I'm curious to know how you're setup for that.

Thanks!
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Old Apr 29, 2010 | 04:17 PM
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my pressure on the car isnt that high. when i turn on the car ill give you a full reading and post here later on
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Old Apr 29, 2010 | 07:10 PM
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It's all about the pressure across the injector. So 80psi base is always 80psi for the injector regardless of boost/vacuum if the vacuum source is hooked up. If the vacuum reference is not there than the pressure difference across the injector will always be changing. There is a practical limit considering that an injector that explodes would not be very useful, typically that limit is regarded to be about 130-140psi.
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Old Apr 29, 2010 | 07:29 PM
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Make sure the fuel pump you're running can even support the elevated pressure.

70psi base pressure + 25psi of boost is 95psi of pressure, add another 15psi for pressure drop from front to back of engine, you're looking at 110psi at the pump. You should check the flow rate at the pressure level since not many pump can supply enough flow at that pressure."
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Old Apr 29, 2010 | 07:49 PM
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Yes, you should be referencing the FPR to manifold pressure to maintain the pressure differential as moremazda stated. I always recommend logging fuel pressure to make sure your pump(s) are keeping up as well.
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Old Apr 29, 2010 | 10:49 PM
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From: Chi -> Maidstone
Thanks. I'm running twin Bosch 044s so I'm good in terms of pumps. With all the other threads it never mentioned whether that was still the case at that high base pressure. But I understand now.

Put simply, in vac they are injecting at 80 psi. At 20 psi boost they would be fighting against that and essentially injecting at 60 psi hence the manifold reference to maintain that 80 psi. I'm sure I said that wrong somehow. I understand it without necessarily being able to explain it.

I'm going to guess the ID injectors can handle
it.
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Old Apr 29, 2010 | 11:23 PM
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Sounds like a fun project, what is the rest of your setup?
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Old Apr 30, 2010 | 04:54 PM
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You are NOT GOOD in terms of pumps.


Bosch pumps will not flow over 80psi.
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Old Apr 30, 2010 | 09:20 PM
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since we are talking alcohol setups... i just posted a thread in the Alternative Fuels Section...

i am looking for setup advice... i need 11,660 CC/Min deliverability of methanol at 30 max boost. (6 ID2000 injectors)

anyone having suggestions would be welcomed. the car is dual purpose... Standing Mile, track day road racing and street.

howard
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Old Apr 30, 2010 | 09:54 PM
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Originally Posted by rx72c
You are NOT GOOD in terms of pumps.


Bosch pumps will not flow over 80psi.
I'm real curious as to why you say this.. ?

I know of many setups running 100psi base pressure with the bosch 044's and the pumps still flowing well..
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Old Apr 30, 2010 | 09:56 PM
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You are NOT GOOD in terms of pumps.


Bosch pumps will not flow over 80psi.


??????

The Bosch Motorsports '044 has one of the LOWEST drops in flow at elevated pressures and draws reasonable current.

However, it does start to choke at 105psi at the pump as Bosch tests it. Note however Bosch uses a more viscous liquid than gas for test and independent testing with gas always shows higher flow rates.



And a little comparison at low pressures. Still, shows my hunch was right when I ditched my A1000 for '044.

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Old May 1, 2010 | 05:13 PM
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Yes compared to those other pumps they are better.

The difference between 5.5litres of fuel per minute and 3.5 litres of fuel per minute is very large and when pushing your fuel system close to its limits which with e85 happens very quickly it will not be adequate.
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Old May 1, 2010 | 10:15 PM
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Originally Posted by rx72c
Yes compared to those other pumps they are better.

The difference between 5.5litres of fuel per minute and 3.5 litres of fuel per minute is very large and when pushing your fuel system close to its limits which with e85 happens very quickly it will not be adequate.
So do you have any useful input for a better alternative to the Bosch, or just a library of ambiguous statements?
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Old May 2, 2010 | 03:20 AM
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http://www.fuelab.com/index.php?page...emart&Itemid=3

How about something like this? Looks to deliver.

Wish chart extended past 100psi to its choke point...
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Old May 2, 2010 | 04:28 AM
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Those prodigy pumps look the goods. I would try one of those.

Last edited by GoodfellaFD3S; May 3, 2010 at 06:50 AM.
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Old May 2, 2010 | 12:40 PM
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STAY AWAY FROM FUELAB! In my experience, total garbage. We tried out one out a when they first came out, killed it quickly, but were supposedly having a lot of issues so they redesigned them supposedly. Got one of the newer ones and only lasted a little while longer.

rx72c, what pumps have you had good luck with and are comparing the 044's with?
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Old May 2, 2010 | 05:35 PM
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From: Chi -> Maidstone
Originally Posted by rx72c
You are NOT GOOD in terms of pumps.


Bosch pumps will not flow over 80psi.
Yep...no info there, so that looks ambiguous to me.

Originally Posted by rx72c
Yes compared to those other pumps they are better.

The difference between 5.5litres of fuel per minute and 3.5 litres of fuel per minute is very large and when pushing your fuel system close to its limits which with e85 happens very quickly it will not be adequate.
Same here...

Originally Posted by rx72c
Ambigious statement? Mate go fuckyourself. i give plenty of good advice on here and dont need ********* like you talk ****. dont have anything good to add then dont bother posting ******. Im sick of people who have a go at me, i simply post up my experience and thats it.

Dont like it. Dont read it.
This is MY thread. The way I see it, you've been no help whatsoever. Way to go on the defensive and stoop down to a teenager vocabulary.

Originally Posted by rx72c
Those prodigy pumps look the goods. I would try one of those.
LOOK the goods? TRY one? You either are talking experience or not. The way I read that, you haven't a clue. Before you **** on someone else for calling you out, how about you actually put up some information to back up your "experience."

If you're not going to post up anything worthwhile, stay outta my thread.
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Old May 2, 2010 | 09:34 PM
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Fine ill stay out of your thread.
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