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odd boy
April 24th, 2008, 05:10 AM
Friends,

What are the right steps I need to follow to increase the hp of a stock car?

then, what will be the difference if I add a ramair to the picture?

then, what will be the difference if I add headers in?

then, what if I add cam too?


Sorry for the long request. :blahblah:

cmitchell17
April 24th, 2008, 05:47 AM
If you have a truck which I don't think you have the main thing is to get rid of the PE delay mode and lean the mixture out to around 12.5 to 1.

joecar
April 24th, 2008, 06:40 AM
Cold air intake gives a few hp, maybe 10 hp.

Headers give about 5%-10% increase in hp; headers will move the torque peak to a different rpm.

Best results are achieve by following up with a calcibration tune, you want your measured AFR to be "right" for peak torque/power.

SSpdDmon
April 24th, 2008, 07:09 AM
Just tuned a bolt-ons (lid, headers, catback, 3.73s), A4 car (2002) a few weekends ago. Made a baseline pull and AFR was only off by 1/2 point. Got 3 hp from leaning it out to ~12.8. Then, got another 7 or 8 hp by increasing timing 2* over stock for a net result of a solid 10hp & 15ft/lbs.

Basically, the steps are to get the AFR dialed in as suggested in the tutorial (don't have to increase the VE by 15% on a near-stock car - 5% should be sufficient). Then, get on a dyno to see what timing it likes.

odd boy
April 24th, 2008, 08:45 AM
Basically, the steps are to get the AFR dialed in as suggested in the tutorial (don't have to increase the VE by 15% on a near-stock car - 5% should be sufficient). Then, get on a dyno to see what timing it likes.


So when I add any thing introduces more air (ramair/cam/larger intake...etc) I should ask {B0101} to accommodate that change by leaning the engine (as first step).

Then, I will command the new AFR (if nesseccary) into {B3605}/{B3618} not exceeding 13 to 1.

What shall I do in case the commanded AFR is not equal to actual one?

After that, the timing part comes.

does it sound cool?

SSpdDmon
April 24th, 2008, 12:26 PM
So when I add any thing introduces more air (ramair/cam/larger intake...etc) I should ask {B0101} to accommodate that change by leaning the engine (as first step).

Then, I will command the new AFR (if nesseccary) into {B3605}/{B3618} not exceeding 13 to 1.

What shall I do in case the commanded AFR is not equal to actual one?

After that, the timing part comes.

does it sound cool?
When you change the airflow characteristics of the engine, you're going to need to re-map B0101. Bolt-ons shouldn't effect it that drastically. This is one of the tables you'll be adjusting so that commanded does equal actual AFR. If it doesn't, then this table may need adjusting. The MAF and the IFR are the other main tables that control whether or not actual=commanded.

Follow the tutorial and read up on how the PCM works. You'll be ok.

cmitchell17
April 25th, 2008, 05:55 AM
I wish I could say my LTs did something on my 5.3. I didnt see anything different from them from the MAF. But I did use a ve table from another 5.3 with the same kind of headers tuned with a WB.

The biggest thing I noticed was getting rid of the PE dealy but I don't think LS1s have them?