Timing for Gas Mileage

[ZX2 User]

Ok guys i'm soon to be doing the timing belt on my '99. 145k Miles and has the factory belt. I know these cars are supposed to be set at 10 degrees BTDC. Now im not to familiar with timing but i have changed a few (not zx2's). I have been reading and alot of people of various cars, said that if i advanced it some i would get a little more TQ and MPG. Now is this good for the zx2 and how far advanced should i run it? Maybe 5 Degrees or 2? Give me your opinions while im sorting out a date and cash to do the belt. Thanks.

[1blackz]

from what I understand you could just unplug the knock sensor and do the iat resistor mod and that seems a hell of a lot easier than doing the timing belt...

[ZX2 User]

Yea but when it comes to those kind of mods i try to keep them as a last resort. I usually tend to mess something up when i go into anything to do with electrical.

[dareall]

Ok guys i'm soon to be doing the timing belt on my '99. 145k Miles and has the factory belt. I know these cars are supposed to be set at 10 degrees BTDC. Now im not to familiar with timing but i have changed a few (not zx2's). I have been reading and alot of people of various cars, said that if i advanced it some i would get a little more TQ and MPG. Now is this good for the zx2 and how far advanced should i run it? Maybe 5 Degrees or 2? Give me your opinions while im sorting out a date and cash to do the belt. Thanks.

the belt is easy and inexpensive to replace. Before you do anything, you need to first determine which timing setup your car currently has. There are a few ways to get an idea (what color is your valve cover, how many wires leading to your MAF) but the only way to be positive is to remove the timing belt cover and look at the upper idler pulley. If the bolt is a torx and recessed you will need the timing set for the 98. If the bolt is exposed and uses a 15mm socket on it, then you will need the newer one. If you do use the newer one, do not try to install the extra pulley which comes in the set (send it to me because I need another one).

if you wish to tinker with advancing the cam timing, it will be easier to do it with a cam gear made for this so you can get a more accurate adjustment. I have a new OBX cam gear I can part with. It looks like this



it is marked for 2 degree increments so adjustments are easy

[ZX2 User]

Ok ill see if i cant look sunday afternoon. Its a black valve cover and ill check the MAF tomorrow. Right now i cant afford anything. THe cam gear looks so promising but you know how that goes. Thanks for the info.

[dareall]

if you have the black valve cover, then you probably have a 6-wire MAF and use the newer timing set. 99's suck when it comes to this for noobs so definitely double check to be sure.

I'll part with the cam gear for $65 shipped when you finally get the cash rounded up if you want to go that route

[ZX2 User]

Sweet. I was hoping for the newer style. Means thats $6 less because i dont have to buy a torx socket. Going from a laborer job $28/HR to delivering pizzas 7/HR sucks. There are no jobs here or i would completely redo the whole car with a tune up. Just sucks. Should of saw the fuel coming out of the fuel filter today. Looked like chocolate milk lmfao.

[Hardline]

Advance the intake cam 4-8 degrees depending on driver taste.

[ZX2 User]

Alright, thanks hardline. I will definatly try that out and see what i like better.

[mechtech]

10 degrees? That sounds like a base ignition timing thing, not cam timing.

Stock[zero] intake timing or a little advanced is good for a normally driven street car. that means in real life, RPM are usually under 3k.
Which they are, for 99.5% of our driving.
Maximum power up high would benefit from a bit of retard on the intake. Exhaust too, as the VCT reverts to it's 'zero' at full throttle.

I would not go more than 6 deg change, though.
Advancing the intake a bit would help auto tranny cars especially. They need every low swinging dick they can glean.

I'd advance it a couple and forget about it.

[5Speed]

10 degrees? That sounds like a base ignition timing thing, not cam timing.

Stock[zero] intake timing or a little advanced is good for a normally driven street car. that means in real life, RPM are usually under 3k.
Which they are, for 99.5% of our driving.
Maximum power up high would benefit from a bit of retard on the intake. Exhaust too, as the VCT reverts to it's 'zero' at full throttle.

I would not go more than 6 deg change, though.
Advancing the intake a bit would help auto tranny cars especially. They need every low swinging dick they can glean.

I'd advance it a couple and forget about it.

As an ATX owner I almost took offense to that low swinging dick comment...

Some advance is a good thing on a daily driver or Automatic car. Every car will be different. Because I don't have an engine Dyno I used multiple passes at the track paying close attention to 60ft times, e.t and mph to gauge how effective advancing the intake gear was.

0 Degree's resulted in the highest mph but slowest E.T
2 Degree's resulted in a little slower mph but faster E.T
4 Degree's resulted in dropping mph a little more, but the fastest E.T
6 Degrees saw both the mph drop nearly 2mph and the E.T started getting slower.

To be honest no gains below 3K where really felt with 2-6 degrees timing even my 60 foot times did not change but that is because the car was leaving off the foot brake @ 2200rpm, but mid range picked up significantly. I don't have dyno's but I feel the gains are in the 3500->5500 range. I was shifting at 6500rpm.

6 Degree's on my Vit tuned sounded like a set of Stage II cams with lots of overlap. Wicked idle.

As far as results the car picked up a .1 of a second in the 1/4. For $100, it was an okay mod, but really shines in daily driving.

[mechtech]

The bit of advance on the intake is not primarily for full throttle gains at low/mid RP, but driveability and torque at smaller throttle openings.
Except maybe briefly in first, this range is not seen at the drag strip.

[SR2000]

my sprockets are both -6 degrees showed more whp @ the dyno ... #imjustsaying

[5Speed]

The bit of advance on the intake is not primarily for full throttle gains at low/mid RP, but driveability and torque at smaller throttle openings.
Except maybe briefly in first, this range is not seen at the drag strip.

Technically isn't opening the valves sooner lowering the rpm torque curve? Meaning power delivery should come on sooner?

[Hardline]

it does, but power delivery will also begin to fall off earlier as well