I have been running my LT1 with a helper pump inline with the stock TBI pump, but i now have another use for that helper pump so i have decided to do it the right way and install the stock TPI pump i have lying around. My question is how much HP is the stock TPI pump good for? If its not much I may just go with an upgraded pump instead.

 

Just go with an LT1 pump. Higher pressure and higher volume. I wouldnt use a TPI pump for anything more than 300 HP. The Walbro 255 is popular but its also noisy because its powerful.

 

Ok did a little research, found that a stok TPI pump is good for 24 gallons an hour. At 350 crank hp with a BSFC of .5 i'll be using 33 gallons an hour. Geuss i'll have to go buy a Walbro.

 

I am surprised the TBI pump with a inline pump was adequate to even start the car. Just go with a walbro 255 and you with be set to go with any future mods.

 

If you do decide to spend the money on a Walbro pump, make sure its a genuine Walbro pump and not one that is "just like a Walbro." There are quite a few cheap knockoffs out there, and they are definitely cheap crap.

 

My stocker fed 400hp, the replacement Walbro 255lph OPSGN is more than enough and it's not loud. 67gph I think, good for WELL over 500hp, some say up to 700.