how do you count the knock on the engine?

[mehrshadvr4]

i saw some people use race gas to have less knock.how do you read it? i have seen some people said 0 knock or 3 knocks.i need to know couse it will help me to boost safly on pump gas.

[corning_d3]

The knock sensor counts detonations inside the engine, and can be counted on a scan tool connected to the DLC. If your going to boost your engine, you need to use high test fuel. Higher combustion chamber pressures and temps normally require you to use it..

[Igovert500]

Race gas isn't necessary unless you are heavily modded. The stock turbos wont be able to flow enough air to need such high octane.

However, keeping an eye on knock is one of the best things you can possibly do when you start tuning. On obd1 cars (91-93) it is really easy. All you need is a datalogger and a palm pilot and you can monitor it while you drive, and turn up the boost accordingly. They are in teh process of doing making similiar software for the hybrids (94-94) and I think as of now, you can do it on them too. OBD2 cars (96-99) are the ones you can't. Which sucks. So for those, other tuning options become necessary. Such as a combination of monitoring wideband o2 readings and the ecu's timing control.

It is hard to explain all the options and factors for tuning, as there is so much. The best way is to really just read as much as you can, and ask when you don't understand, so that you can figure out which direction you want to take.

The bottom line though, if you have a 91-93, one of the first things you shoudl buy is a datalogger and palm pilot because it is an invaluable resource. Until you are monitoring knock, or learn to tune, you really shouldn't go above 14psi. Some say 14.5, or 15, but 14 about as much as I'd suggest pushing it. This works out well though, because the stock turbos (9bs) really can't do much better. Going beyond isn't really necessary until you make fuel/turbo upgrades.

[Stealthee]

Shiver has had his 94-96 loggers out for a while now. I want one.

And yes no need for race gas unless you are highly modded.

[mehrshadvr4]

ok so what should i buy to count my knocks?i have 93 vr4.

[Linebckr49]

Originally Posted by mehrshadvr4

ok so what should i buy to count my knocks?i have 93 vr4.

buy a cheap palm pilot off ebay. then get a datalogging program.

read through this thread and it should answer many of your questions: http://www.automotiveforums.com/vbul...ght=datalogger

[Igovert500]

http://automotive.miragecorp.com/

software and cables available here. Then all you need is a cheap palm off ebay like Linebckr mentioned.

[Linebckr49]

oops. ya i forgot to mention the cable. you'll need one to connect the datalogger (palm pilot or laptop computer) to the in-car diagnostic port. i got my cable off ebay a few years ago for about 45 bucks. you might search around, i'm sure there are other options than the miragecorp $70 cable.

and as for datalogging software, the link i provided offers many differen't software options, and compares them. the open source one i use from MMCd is free and can log more parameters than the others. but you can read all about that.

[Linebckr49]

the same guy i purchased my datalog cable from off ebay 3 years ago is still selling them on ebay! here's a link to some of his auctions: http://search.ebay.com/_W0QQfgtpZ1QQ...untdepolygonze. his cables only work with first gen 3S's (91-93), and since you have a 93 vr4, you're in luck. its 35 bucks, shipping included, so half the price of the miragecorp cable.

[mehrshadvr4]

thank you guys