hey guys, i will be running the mods in my sig. i expect between 13# and 15# of boost. so i have a set of 42 inj. on the car righjt now and i know it wont really be enough. my buddy has a set of 50 inj that he would trade me becuase he only needs 42inj. so should i go for it or try to sell my injectors and buy some 60.

 

60's would be best, but more importantly, dual 255 pumps in parallel vs your single. A single 255 probably won't be able to supply the "volume" for that stroker at that boost level.

Ken R.

 

I'd start with the 60# injectors and a dual in-tank pump setup through the stock lines to start and then see what needs upgrading. Run the 2nd pump off of a hobbs boost switch. The stock lines/rail configuration will support a surprising amount of fuel and power.

 

This is exactly how we set up mine with 15#'s of boost and its running perfect.

 

ok so could i just buy a 2nd pump, or is there a whole kit to buy to run 2 pumps? also what is a hobbs switch? never heard of that.

 

There's no "kit" that I am aware of on the market. You just will need to buy a second Walbro fuel pump and install it in your tank. There are several good write ups on this (I think there used to be a sticky at the top of this forum. Try a search and you should find it).

As for the HOBBS switch, it is a boost referenced switch that once senses a pre-set boost level, it will kick on the 2nd fuel pump. Mine is setup this way as my HOBBS switch kicks my 2nd fuel pump on at 4#'s of boost.

 

Lonnies Performance sells the Racetronix Double Pumper. It's pricey though. You can easily plumb in a 2nd pump for about $150 after it's done. Look at the sticky at the top of this forum.

 

do you really need to run 2 255? would a stock pump on the boost reference switch do?

 

It's the widest used most successfull combo for the 450-1000 RWHP boosted application. Not sure if having a stock pump for the #2 pump that kicks in with the boost reference would work or not. When the 2nd pump kicks in, thats when you need the extra fuel the most though. Not sure the price difference between a stock pump and a Walbro 255, but considering you can get a new Walbro unit for about $100, I'd bet the stock pump isn't far off in price, making it an even easier decision IMO.