Originally Posted by
jere 
Don't do waste of time, the cat back isn't going to be much of a gain esp if going into stock muffler.(I feel your pain there though I have a stock cat back on my turbo NX ) If you are strapped for cash timing is really a good one
Ah and thats what my quest is all about. I got a cat back 2.5" system couple weeks ago. I will say my butt dyno felt a torque increase. I hated how loud it is though. So this Saturday I went out and got a Turbo muffler. It's much quieter then the rice muffler that came on the ebay cat back. But still pretty loud, at least it's deep loud, not too raspy
As compared to:
Originally Posted by
Fastspec2 Fuel economy has alot to do with timing. As the propper amount of timing for any given throttle position, including wot, will result in more cyl pressure. The propper amount of timing for a given fuel and engine varies. By advancing the timing and running better fuel you will not only see an improvement in wot HP but in part throttle fuel economy. Back when gas was 1.25 and premium was 1.45 it made sense to tune a car for regular as the percentage of cost for the better fuel was really hi. Anymore, as gas is 3.25 a gallon give or take, and premium is still only 20 cents more a gallon, it pays to buy better fuel. I have shown a number of times on a number of different cars (mostly v-8 domestics) that tuning for premium and running better fuel yeilds more miles per dollar spent. Add that to the fact that the additive package in premium is so much better and you get better economy, cleaner injectors and valves, oil gets less contaminated, yada yada yada. I'm willing to bet you that on an accurate spread sheet that tuning your car for premium fuel costs less per mile travelled as long as the price of premium stays 20 cents more than regular. Oh yeah, and it will make more HP.
From what I heard bumping your timing and running higher octane gas (to keep the engine from knocking), will give you better gas mileage. Why? Because the fuel will have more time to burn up completely and have use, instead of going out the exhaust and burning up in the cat...
Originally Posted by
billc You can advance the timing to 17* and still run mid-grade safely. At least check your timing if you have not yet done so. When I bought my SE-R the timing was set at 13* and I gained 8 whp on the dyno by moving it to 17* -- with lots of improvement in the mid-range. I could feel this on the road.
A Calum ECU would be worth considering. I can't believe the improvement I have seen in my NA daily driver with the Calum ECU ($125 or so). The best part is you can switch back in the the OEM program for emissions testing. Do some research on this and see what you think. I'm getting 30-34 mpg of high test in mixed driving with mine.
If you ever get a clutch job, get the Fidanza (or similar) flywheel. Great mod!
Bill
Your getting me interested in the Calum ECU
. With the Calum ecu, can you have to keep the timing at 15* right? So that it can advance and retard the timing automatically... or is that only the JWT ecu?
Be the first to like this post.
Back to top