Page 3 of 42

Re: Sc14 to buick and e85

Posted: Sun May 25, 2014 10:24 pm
by VL400
If its happy on 300kpa and injector duty cycle is under 80% leave it as is. If you need more fuel might need to bump up the pressure.

Re: Sc14 to buick and e85

Posted: Sun May 25, 2014 10:42 pm
by TdracerTd
The reason I had my injector flow rate at 300kPa is because that is stock for the vp injectors and I wasn't sure I had all the bits I needed to modify the fuel rail for the adjustable reg that I had. The l67 injectors I am now running are supposed to flow 39 lb at 350 kPa. I'm thinking that I should go to at least 350kPa.

What are th disadvantages of going higher?

How much is too much?

Re: Sc14 to buick and e85

Posted: Mon May 26, 2014 10:20 am
by VL400
Unless VS was different, the super 6 injectors are rated for 37lb at 3.5bar/350kPa. Running them at the manufacturer specified pressure is often better as it ensures the spray pattern is ok.

Going too high can cause an injector to get stuck open but normally need to wind it up pretty high for that.

Re: Sc14 to buick and e85

Posted: Mon May 26, 2014 11:13 am
by TdracerTd
Just ordered an 87mm (8 PSI) Pulley. I'm hooked!

Re: Sc14 to buick and e85

Posted: Tue May 27, 2014 9:46 am
by TdracerTd
Could one of you run your eye over my tune? See if anything jumps out.

Re: Sc14 to buick and e85

Posted: Tue May 27, 2014 12:05 pm
by Holden202T
what is the file a tunerpro log ? shouldn't it have xdl extension ?

Re: Sc14 to buick and e85

Posted: Tue May 27, 2014 12:24 pm
by TdracerTd
oops. wrong file.

Re: Sc14 to buick and e85

Posted: Tue May 27, 2014 2:00 pm
by Holden202T
mostly it looked ok, i have found a few bits you missed and added them in .... like Cold Engine boost AFR tables were zeros!

also a fuel decay that would have made it pretty rich on startup (still had petrol afr's in there)

Re: Sc14 to buick and e85

Posted: Tue May 27, 2014 2:51 pm
by TdracerTd
Thanks for that.

I can see some of the areas that you changed. Are the numbers derived from other numbers that are in the tune? Is there any information in the tuning guides that I have missed regarding these?

Re: Sc14 to buick and e85

Posted: Tue May 27, 2014 3:33 pm
by Holden202T
from memory the tuning guide just says to change all the stuff related to fuelling to suit ..... but the fuel decay one i changed for you is something that i totally missed for a long time, and it was only when i was trying to iron some bugs out of a v6 sprintcar tune that i found i had missed that table ... basically what it does, when you start your car it will start richer and slowly lean off to commanded idle afr ... this is fine, but when you make a tune for a v6 sprint car running methanol which requires 2.3 times more than petrol, that AFR increase in that table of 3.00 changes 6.4 to 3.4 .... basically floods the motor for the first 30 seconds or whatever the number is!

the problem is, v6 sprint cars are direct drive, they lock it in gear and then roll start on the starter motor, so then as soon as it fires they are moving, if they have a stoppage then re-start the car is sooo flooded that it takes a lap or two till it clears! .... so that was a hard one to find and work out because i just wasn't thinking about it :)

in your case running E85 its not so much more that its bad enough to do that i don't think but it will probably make it a bit richer on startup than is required.

also your boost AFR tables where the same value across the board as the 100kpa column of the 20-100kpa table, with boost you want to go richer as you put more boost into it .... for petrol you probably want to target about 11-11.5 AFR for say 15-20psi of boost, maybe even richer to be safe, but theres a fine line, too lean you will kill something, too rich and you can flood it! anyways, i generally make boost AFR tables go from 100kpa numbers down to something like mentioned above, and so i have applied that to yours, and i know you probably wont see much more than 5-10psi with the SC14 but the tables right for anything up to 15psi and in terms of the 7.3 AFR in the 200kpa column, its about the same as running a petrol motor on 11 afr!

the E85 numbers i put in are what i had set my Turbo Gemini to when i tried E85.

start safe and once you have a decent tune you can lean out as required.

i am also not really sure on your injector rate, i guess that will just have to be a bit of suck it and see as you go along, but the calc looks pretty close to where i'd start anyways assuming they are 39lb injectors.