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Fuel Time For More Fuel?

  • Thread starter Thread starter madspeed
  • Start date Start date Dec 2, 2013
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madspeed

Colonel Mustard
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Finally thinking about replacing my bad head gasket on my stock block turbo'd 333. Currently running a 255 high pressure in tank pump along with 60# injectors on stock rails. What's the hp limit my fuel setup is safe at? I'm guessing i should be around the 500 hp mark on 10 psi. Just wondering if a bigger fuel pump or a boost a pump would be of any help in keeping me safe??
 

84Ttop

They make new pistons every day, so why worry?
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#2
  • Dec 3, 2013
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Above 500 rwhp a single 255 pump doesn't cut it. Years past I've used a 255 in tank and a Trex in line pump. Also I would start to look at upgrading your fuel rails. It's my experience that the stock fuel rails will support 42 lb injectors at 80% duty cycle. But I wouldn't push my luck past that. The ultimate upgrade would be sump the tank run some new lines aftermarket fuel rails and never look back.
 

madspeed

Colonel Mustard
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340 in tank should be more than capable of supporting my stock block then?
 

84Ttop

They make new pistons every day, so why worry?
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#4
  • Dec 5, 2013
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I've seen the 340 support 630 rwhp on a recent dyno session we had with a customers convertible. To answer more directly yes it exceeds you stock block by far!
 

Grabbin' Asphalt

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Feed the Monster!!!
 

madspeed

Colonel Mustard
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#6
  • Dec 5, 2013
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any recomendations as to which 340 lph in tank pump to source?
 

MikeH686

Mine is only two inches though.
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#7
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Ive read good reviews on the aeromotive
 

A5literMan

At least it is lumpy...
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I'd go with aeromotive
 

84Ttop

They make new pistons every day, so why worry?
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x3 for aeromotive!
 

elarm1

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aeromotive baby!!!
 

85rkyboby

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#11
  • Dec 6, 2013
  • #11
Magna Fuel or Fuel Lab
 

2000xp8

SN Certified Technician
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Dec 6, 2013
#12
  • Dec 6, 2013
  • #12
I really don't see how a fuel pump is going to help anything in this situation.
500rwhp is the blocks limit and even that number is an overestimate.

42's and a high pressure gss340 255 works with more than a stock block can handle.

Fuels system parts are ridiculously expensive. If there is no immediate future plan or back up plan in place for a race block, there really isn't any point in spending money on fuel parts.

Have the car dyno'ed and turn down the boost to save the block if it makes too much power.

Driving around a ticking time bomb gets old quick.
 

madspeed

Colonel Mustard
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#13
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agreed, i'll say that i'm runing on a 9 year old Holley 255 pump and will likely be neding a new one before too long, might as well upgrade. I am also saving up for a Dart block to turn up the wick
 
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2000xp8

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madspeed said:
agreed, i'll say that i'm runing on a 9 year old Holley 255 pump and will likely be neding a new one before too long, might as well upgrade. I am also saving up for a Dart block to turn up the wick
Click to expand...

If you want to change the pump as preventive maintenance, i get it. I was more or less responding to your original post suggesting you would like to make your setup safer. At 500rwhp, nothing is really safe.

I would slap a gss340 in the tank if you are worried about pump reliability, then when you get your new block build an entire fuel system. Budget 2 grand for it, my estimate on a fuel system was way the hell off.
 

madspeed

Colonel Mustard
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#15
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The Holley pump i have is the high pressure version built for boost, basically the same as a gss340, so if im buying anything i should make it an upgrade
 

Grabbin' Asphalt

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#16
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Like injectors, if you're replacing anyways might as well grow into a set if you're going Bigger later
 

2000xp8

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#17
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madspeed said:
The Holley pump i have is the high pressure version built for boost, basically the same as a gss340, so if im buying anything i should make it an upgrade
Click to expand...

If you have an hp pump, i'd just leave it. Pumps don't go bad that often and it's a enough to supply your current setup. Walbro's are pretty damn reliable.

If you upgrade the pump there is no guarantee you are going to be able to use it later. Unless things have changed (and they may have) the stock fuel hat outltets will be undersized for your future use and they don't connect in any way to a real fuel system.

IMO, save your money and build the fuel system all at once.

And asphalt, it is NOT a good idea to oversize injectors, that is a sure fire way to land up needing a computer tune to get the car to run right. Run the parts you need now, not later if you want your car to run right.
If that were the case there would be no reason for anything smaller than 42lb injectors to exist.
Put 42lb injectors on a h/c/i car even with the right meter and see how it runs, it won't be good.
 
Last edited: Dec 7, 2013

madspeed

Colonel Mustard
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Nov 29, 1999
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Dec 7, 2013
#18
  • Dec 7, 2013
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No worries on the injectors for now, running 60# and moates quarterhorse tuned
 

madspeed

Colonel Mustard
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#19
  • Dec 7, 2013
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2000xp8 said:
Put 42lb injectors on a h/c/i car even with the right meter and see how it runs, it won't be good.
Click to expand...


Disagree... I was running 42's on my hci car before the tirbo install and she ran great. Not to say a tune wouldnt of helped, but...
 
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Grabbin' Asphalt

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#20
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Getting a tune with "no room to grow" injectors or getting a tune with "room to grow" injectors will still leave the owner with getting 2 tunes for each set up anyways when the jump happens. Why not buy injectors once
 
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