:raises hand: Plus I need two (trail spare) so that's extra cash I can use elsewhere.
CK5
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Edelbrock Proflo 4
- Thread starter 6872xtc
- Start date
:raises hand: Plus I need two (trail spare) so that's extra cash I can use elsewhere.
I had a 255 in the 87 K5 stock tank I did YEARS ago. Its a very easy swap, same dimensions as stock pump. Even my wire harness matched the stock. 450 LPH is a different story which I wrote about in my build.
$30 extra? Hell a dinner cost that!
You can always use the old stock pump as a spare to get you home or buy a spare EP381 just for temp use. Many sell a used 255 pump cheap. Like 20 bucks since they upgrade to something bigger. I have two spares as of now.
$30 extra? Hell a dinner cost that!
They're only $70? I remember them being over a $100 a piece.
Actually.... $52! Just found this. Looks like its coming straight from Walbro so I don't think it would be a fake but I'd double check.
https://www.amazon.com/Walbro-GSS342-Fuel-Pump/dp/B000EVN7W8
if they were that cheap back when I bought mine I may have gone that route. I paid $43 each for the Delco's.
Just did a little scan through the GM and AC Delco parts catalogs. They don't give any specs on the pump at all. Psi or lph.
Scanning the web came back with some details, but they were answers to questions posted on summit where some random dude posted what he thought the lph rating was. Nothing I'd hold my hat on for being accurate.
Only clue I got is the EP381 is the spec pump is that it's the same part called out for the L30(305), L31(350) and L29(454). Other than that I can't find the lph specs for that pump.
It is the same pump Larry has used for his 8.1 swaps too. He typically runs the fuel pressure in the high 60's (55-62 psi is stock for an 8.1) and has not had any starving for fuel under load. He's using a stock tbi style fuel filter too, as I am with my 5.3 but I'm running the 241 due to my ecm setup.
Scanning the web came back with some details, but they were answers to questions posted on summit where some random dude posted what he thought the lph rating was. Nothing I'd hold my hat on for being accurate.
Only clue I got is the EP381 is the spec pump is that it's the same part called out for the L30(305), L31(350) and L29(454). Other than that I can't find the lph specs for that pump.
It is the same pump Larry has used for his 8.1 swaps too. He typically runs the fuel pressure in the high 60's (55-62 psi is stock for an 8.1) and has not had any starving for fuel under load. He's using a stock tbi style fuel filter too, as I am with my 5.3 but I'm running the 241 due to my ecm setup.
I do believe Edelbrock is advising on the side of caution with the 210 suggestion
I know a 241 will feed a 400hp lt1 no problem
Margin of error being what it is
At $52 I will go walbro since I may be in that margin of error
I know a 241 will feed a 400hp lt1 no problem
Margin of error being what it is
At $52 I will go walbro since I may be in that margin of error
A stock 8.1 is 330hp at crank so it might be ok for that but why take a chance on a smaller pump and have a possible lean condition? If the 8.1 is modified with higher flowing heads and larger TB then I'd suggest against it. You always want to run a bigger pump than you anticipate HP wise.
I was reading that the other day. Also GM is rating that at 425. Margin of error...
ekajkrats
1/2 ton status
I found one other site beside rockauto stating the ep381 was 27 Gallons per hour:
https://www.rockauto.com/en/moreinfo.php?pk=90717&jsn=3
https://www.rockauto.com/en/moreinfo.php?pk=90717&jsn=3
In a round about way yep.
They are basically stock 8.1's. Other than the tune. Having witnessed him pulling away from me on every mountain pass I can attest that the 381 pump is more than keeping up with the 8.1's demands.
Modification would certainly put it into the need for more pump. And at least as far as the spec is for the 8.1 for fuel pressure, the 381 does have the same ability as the later pumps that came in the gmt800 trucks with the 8.1 originally. Still don't know what the lph rating is, but it works for that application.
27 gallons per hour is only 102 LPH. I think its at least 155 LPH
Agree. Should be fine for a stock 8.1. Anything more than than that will need something larger. A 255 is almost plug and play especially with the correct harness adapter.
For most 350ish engines with stock or even Vortec heads, the 381 should be fine. You're probably not over 300-350hp at crank. On the other hand if you slap some high flowing alum AFR heads on and a decent cam, then you are looking to be closer to 400hp at the crank and the 381 pump would not provide enough. or you will be close to the limitations.So all of this confirms that my little 354 small block is just fine with the 381 pump. I just have to confirm this by watching the fuel pressure.
@mrk5 , I didn't have to add a pressure gauge to my Broflo..
Now that we found Walbro 255 legit pumps for around $52, there's no reason not to go bigger if you plan on making more HP.
Depends on the stickers on the back window.
I would think you are well over 350hp with those heads. Edelbrock heads flow pretty good and have used them in the past on a 496 build. One option is to look at Edelbrock crate engines with similar heads and cam profile. Even a non roller cam can easily make 400+hp like this one below.
https://www.edelbrock.com/performer-rpm-410-crate-engine-45610.html
As far as elevation, you still need a decent size pump. Here in Denver we can subtract 20% on HP but we still need a decent pump. I've always had to go with larger pumps even on my race car. Dual 255 pumps were not enough and we hit a wall at 800whp here on the dyno but that was E85 with huge turbo.
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