I'm running a d16y8 with 9:1 CPs and I was always wondering, if I could add timing to my vacuum low rpm area to compensate for the lack of low end. What have you guys done in that area of the map?

 

In for this.

 

bump for driveability

 

you could, how much exactly? i dont have a clue... listen for pingin. lol

 

I've always wondered since all the turbo guys are now running 93octane on their cars if you could add timing throughout the low rpm ranges, the ranges that don't see boost because of the added detonation threshold. I would think so especially if your running lower comp pistons say ~8.5, i want to verify though.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GiNuWiNe &raquo;</TD></TR><TR><TD CLASS="quote">I've always wondered since all the turbo guys are now running 93octane on their cars if you could add timing throughout the low rpm ranges, the ranges that don't see boost because of the added detonation threshold. I would think so especially if your running lower comp pistons say ~8.5, i want to verify though. </TD></TR></TABLE>

well stock is 9.5:1 and i'm running 9:1, so you would think there is some "breathing room" for added timing, especially since I'm running 93 octane all the time. My car is a dog trying to drive i vacuum on the streets.

 

bump

 

I have a map with a well bumped timing under vacuum .. I haven't tried it, but the guy that gave it to ma said that he has some coolant problems. But I believe that's due to his too much timing under boost. So, in short, the timing in the vacuum cells is upped with about 3 to 4 degrees ..

you can always bump your timing in vac, and see what's gonna happen .. but you shold have an EGT gauge to monitor the exhaust as well

on average, you can bump 2 degrees if you're running 93 gas always, and that's gonna make your car somewhat faster under vacuum.

 

More info

 

i dont think .4 compression points is a huge huge difference.

you could bump the timing, maybe a degree or so, thats all i usually do

 

Although the decrease in compression is minimal, you're still running 93octane instead of 87.

 

get on a load dyno and tune it

 

You guys do realize that adding timing does not always equate in power gains right?

 

Thanks bud. Anymore words of wisdom?

You can add alot of timing on low compression. However its probably the hardest thing to tune because you wont get any detonation at low throttle unless its outrageously advanced or it will be extremely hard to detect. You can use a dyno but you'd be there all day or you can do it by feel on the street. The margin for error here is wide so play around.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Muckman &raquo;</TD></TR><TR><TD CLASS="quote">Thanks bud. Anymore words of wisdom?

You can add alot of timing on low compression. However its probably the hardest thing to tune because you wont get any detonation at low throttle unless its outrageously advanced or it will be extremely hard to detect. You can use a dyno but you'd be there all day or you can do it by feel on the street. The margin for error here is wide so play around.</TD></TR></TABLE>

Um, no. Even if you think that, he still has a Y8 and the margin for error on those suckers through out the powerband is **** due to their "if you run any excessive timing we are going to lift your head in disstaste" stance in life.

The best answer in this thread was to stick it in a dyno that allows steady state loading and t00n the sucker.

 

yep, the only real way is on a load bearing dyno. But with that much of a difference in compression I wouldn't worry about it too much.

But, it definitley plays a role when you run something like vitara pistons or drop a GSR or B16 down to 9:1, the addition of timing in the part throttle maps help get the car moving and make it much more responsive.