Read This To Understand Tuning

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Read this to understand tuning Dec 25, 2006
Tuning is VERY simple, as long as you have a fuel controller (piggyback) or a stand alone system. Whatever the case, you have control over injectors (hi or low imp) and (very desirable) timing control, also known as spark control.


In dial in safe AFR (air-fuel ratio, the amount of air and fuel entering the engine) the preferred ratio is 12.5:1. Meaning 12.5 particales of air to one partical of fuel, but that ratio is for WOT (wide open throttle), while cruising and idling situations, one should expect to dial in 14.7-15.1:1. If you get a bone stock car (toyota corolla, ferrari enzo), and you stick a wideband O2 sensor in the exhaust (before the muffles) you will see those ratios (+/- 1%).

Timing control is very tricky, factory cars differ greatly in timing control, there is no real baseline. Some cars have a total timing of 33-34 degrees BDC (bottom dead center), some have more advanced such as 27-30 degrees BDC. The only way to know i you are at least safe, is to have a knock sensor and an EGT (exhaust gauge temp) sensor. The knock sensor should be hooked up to the ECU (stand alone) and programmed to retard ignition automatically once knock is detected (milliseconds before you even hear it). EGT's are usually in the 1,500F (+/- 50F)m but it is not uncommon to have 1,800F, but that is the limit, anything more and you are asking for trouble.

High EGT's occure when you have too much retard ignition, so one would have to advance ignition untill the EGT's are safe. If knocking occures with , then one should examine the load vs RPM chart of timing, there would be a couple (or more) degrees. For turbocharged cars, the rule of thumb is for every 1psi boost increase, 2 degrees retard should be applied (total timing).

There is no way to monitor timing, all you have are results from exhaust temp and knock, unlike wiebands and AFR....... I have literally seens shops here (no names) that hook up stand alone systems for Dhs 15,000 and just dial in whatever fuel (+/- injector voltages) and timing THEY ASSUME, nothing is taken off gauges and or the dyno......

Hoep this helps clearing things up......

Here are a few modifications one could do without touching the AFR or timimg:

Exhaust system (headers/mufflers, bigger system, etc). dos NOT require tuning, since the engine is still taking in the same fuel and timing.

"Sports" are filters, i never saw even a 1hp gain from them, but still teh amount of air MEASURED by the engine is still the same, thus no tuining.

Upgraded ignition systems, no real big HP numbers, they just make up for lost power set by factory systems, no tuning needed.

Adding camshafts, ported cylinder heads, bigger valves, turbochargers(bigger, smaller or stock but faster spooling ones) DO need tuning.

hosrom_951
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Dec 25, 2006
Here is a more clear understanding of ignition timing:

Link
hosrom_951
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Dec 26, 2006
right, timing is the most important part of tuning up your horses + all the stuff you do to your injector..
ahamed
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Dec 26, 2006
If you really want to stay away from tuning, there are very well known companies in the US that sell true kit. What i mean by true kits as in you recieve all the hardware AND software, such as turbocharger, mounting brakets, pipes, connectors and either chips or software. A real plug and play kit, i actually know a friend who i convinced to get a true kit from the US on this C5 corvette.

It took us ~5-6 hours to install the kit (twin turbo C5 kit), and around 15 mins to upload the software. On the dyno,m the AFR was rock solid 12.3:1 on WOT all the way to redline and the timinmg map was set on pump gas, there was a race gas map, but we did not use that due to the fact you should run on 105+ octane fuel. He put down and very healthy 532whp/512Ft/tq at the rear wheels. That's over 620+Bhp opn the crank, race gas map would bring up the numbers, due to advanced and more aggressive timing, but we played it safe. The car drive's just like the factory, only with much more power and virtually no lag.

A real kit is expensive, he paid over $7,000, and another $380 for shipping, but it was well worth it.
hosrom_951
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Dec 26, 2006
if the output is that, then its worth it ? how about the fuel ?? anything to enhance the average
ahamed
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Dec 27, 2006
for those of you who want to read up on engines, trannies, lsd...etc heres a useful link:

http://auto.howstuffworks.com/index.htm
asdfasdf128
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Dec 31, 2006
ahamed wrote:if the output is that, then its worth it ? how about the fuel ?? anything to enhance the average


It is definately worth itm a true plug and play kit.

Pump gas is all that is required, 93US, or 98RON. The timing, AFR, Injectors have all been addressed.
hosrom_951
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Dec 31, 2006
asdfasdf128 wrote:for those of you who want to read up on engines, trannies, lsd...etc heres a useful link:

http://auto.howstuffworks.com/index.htm


Sorry, but that pisses me off a bit. Fine, go ahead and READ all you want, take it to real world experience, it is different.
hosrom_951
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