In tank TBI pump for higher pressure?

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Nov 15, 2005 | 04:46 PM
  #1  
I want to crank the pressure up a bit more on my TBI before I spend a lot of time tuning. I'm thinking maybe 20ish would be good for my mild 350 and 55# injectors on a bored TB.

I'm sure the answer is here, probably many times, but searching for "fuel pump" is not very useful, and other qualifiers don't help much. So, if you don't mind, the question is, what part number provides the best in-tank replacement for sustaining 20-25 psi, maybe 30 at the outside. From what I think I understand from all my reading is that these pressures are reasonable on a TBI, were available on some stock 454s, and provide a good starting point for my 350.
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Nov 15, 2005 | 04:53 PM
  #2  
I should add, I've seen the posts on the Walbro 190. I just don't want the pump to overload the regulator like some of the people have posted (i.e. not be able to get the pressure down at idle). I also want a stock application if possible so that I can easily get relatively inexpensive replacements in BFE at AutoZone on a Sunday afternoon. Inexpensive is also good in that I will likely be carrying a spare on extended off-roat outings.
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Nov 15, 2005 | 07:16 PM
  #3  
maybe a 9c1 (the LO5 version) caprice pump? or a 454 tbi pump?
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Nov 15, 2005 | 07:40 PM
  #4  
How much power are you looking at making? The TPI pumps are good to at least 48psi.

The key will be making sure you get enought pump to support the HP you need. Most EFI pumps are designed to operate above 40psi, since almost every port injection system out there uses high pressure.
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Nov 23, 2005 | 11:02 PM
  #5  
your stock fuel pump is cabable of twice the required fuel pressure. what you need to do is play around with the fuel pressure regulator. the idea is to create a restriction in the return line which inturn bumps up fuel pressure.
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Nov 23, 2005 | 11:48 PM
  #6  
As I said earlier in my post and title, I'm running a 350 TBI which is spec'd for 9-13 psi. This is not TPI or other high pressure EFI, and the stock pump won't come close to what I want. Earlier OEM replacements sometimes will go 16+ psi, but not much more, and none of the new pumps (including Walbro and Delco) will run over 15 consistently, and that is pretty much dead-headed. The relatively fresh Delco unit in my K5 right now dead-headed at just under 15 psi and I had to back off to around 14 psi to feel confident it would not burn up too fast.

I found out that a 94-95 (IIRC) 454 TBI has a 30 psi spec pump that is a direct replacement for the lower pressure 350 TBI in tank pump. I just bought one last week but have not got it in yet. Unfortunately, I guess due to shorter runs and less coverage (no economy of scale) it costs about twice what a typical SBC TBI pump costs. Last Delco pump I got was about $50 or so, and this one was right at $100…
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Nov 24, 2005 | 09:16 AM
  #7  
get a walbro 255lph and call it a day... nuff said... it works great
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Nov 24, 2005 | 11:42 AM
  #8  
Well, I thought about that too, but not long ago there was a post where a guy was having trouble not being able to keep pressures low enough at idle. <shrug> I guess it's irrelevant now anyway since I found out about the 94-5 454 pumps and bought one a couple of days back...
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