Hi I have a simi built gsr with pr3 pistons 2layer head gasket built gsr head. Blox type a cams sk2 pro sires intake with 70mm tb and I was woundering I wanna get it tuned on e85 so what's size injecters do you recomend. It's a daily I have a set of 310cc but was thinking those are too small. Thanks

 

Why do you think you need E85 for that set up ? For a daily, all you will gain is crappy fuel economy... and maybe 4 to 6 wheel HP assuming both tunes are quality ones. You will use 34% more fuel by volume running E85... so your fuel injector sizing would calculate as follows: 240 x 1.34 = 321cc. Since stock fuel injectors max out around 190 wheel HP at conventional fuel pressures, you would either need to use something larger (420-440cc) or run elevated static baseline fuel pressures to increase the fuel delivery.

 

I just figured around 11.6:1 compression it would just be safer to run e85 . So 440cc injecters will be fine to be tuned on e85. Or do you recomend I just get it tuned on 92oct what size would I need then. Thanks for your imput

 

Agreed. I've been at 12.5:1 on 93 octane for over a decade with 450cc Toyota injectors, on one of my builds making over 210whp.

In addition, if you don't run the right type of injector that optimizes use of E85, you could ruin the injector, and thus, the engine, too.

 

I would tune it on premium personally just for simplicity’s sake. I don’t think you’ll pick up enough power to be worth it on e85 for the decrease in fuel economy. My buddy’s k24 picked up 12whp and torque across the board from switching to e85 with no timing changes at all but his motor is also just under 13 to 1. That being said we don’t have an ethanol pump anywhere near my house it’s an hour drive minimum to go get that fuel for me so I’m kinda stuck with pump or vp110 unless I wanted to get the ethanol in a drum. 11.6 to 1 comp will be very happy on premium as long as you have some cams that are bigger then b16’s.

 

Oh cool thanx I guess I'll stick with pump gas. Even though here in vegas there a ethanol pump on every corner and is cheaper. Ibut we also have 100oct pumps all over the place here too. So I would be safef I wanted to swap out the pistons for jdm itr p72-00. To be around 12.1 would it still be safe. What injecter size you recomend for pump gas. And speaking of cams what would you recomend. I have a full b18c1 with b16 pistons milled head.010 bllox valve train. But thinking of going up to jdm p73-00 pistons witch will bump my compression a lil over 12:1

 

Compression on its own doesn’t necessarily make more power, it really needs the camshaft profile to take advantage of that (it’s actually the other way around, cams need enough static compression ratio to bring the dynamic compression ratio back to where it should be for enough cylinder pressure) for a 12 to 1 1.8l on pump gas there’s quite a few cams that would work well, skunk2 tuner 2’s/ blox b’s would probably be my first choice. You could go pro1’s but I’ve never personally been a big fan of them. That motor on some tuner 2’s would be a fun setup though.

 

Oh cool i was thinking the sk2 s2 cams too. But what injecter size do you recommend for pump gas and 12:1 comp. 370cc or 440cc. I dont wanna go to big

 

I have 320’s on pump gas on my all motor d series that are 102-108% duty cycle. I would probably go with 550’s so you have enough injector for sure.

 

Contact your Bosch person. I've got Bosch Injector (1000/040S/14mm) with a GM Flex Fuel Sensor Kit (for Ethanol content and temperature). Plus I have a Honeywell 150psi Pressure Sensor. All this operates thru a Emtron Electronics Package. My engine is NA 320hp @ 9100. Gearbox is a Holinger SF https://holinger.com.au/showroom/sf