Ted B,

I have Vishnu cam gears and they are set to -4/-1. Unless they've changed the design in the last two months, your Vishnu cam gears line up using the tooth with the red dot on it as the zero mark (not the tooth above the 0 degree mark). There's a whole thread on this in the Vishnu forum...

l8r)

 

how do you adjust your vishnu gears? loosen bolts then what? what do i turn the teeth or the body?

 

they're prob not. but they are set up for stock cams. New cam- new gear settings.

 

getting...AEM gears in today..will the -4/-1 setting feel that different from using stock gears??

 

get these in your car yet 93civEJ1?how it feel now?

 

actually yeah I got the cam gears in, I dont know if you will really feel a difference just doing the cam gears, but when you start tuning the whole car the probably help a bit. Actually idle is a little better now after getting the cam gears on, unfortunatly i did not do the -4,-1 setting.

 

what setting did you end up with to fix your idle problem.

 

We ended up doing a -4,-4 setting.

 

so -4,-4. Does it idle good for a while then start that up and down BS. That's what mine does a -4,-2 it seems like -2 helped more than -1 on the ex. side

 

actually, when i was just straight factory settings, id did the idle up and down routine, but i dnt think you will completely get rid of that. Thats the ECU hunting for the stoich a/f ratio at idle. Its either adding or taking away fuel. It did take that away, and it does not do that as much as before.

 

Yup that's what I thought. I cranked up the idle to about 1,000-1,050 and it cool for most of the time. Every now and then it'll do that. I think you have to have the ignition timing advanced alittle to take full advantage, like silver surfer said.

 

Yeah, with cams such as the 272's i dont think youll get it gone completly.

 

I've been really thinking about a 264 intake cam. I'm going to get the car tuned, then make my decision.

 

264/272 or 272/272 The 272/272 combo runs perfect but let me give some hints here. First the point of timing gears: when a factory cam is produced it has to fall into certain specs one of which is the centerline of the lobe (intake 71deg BBDC Exh 70 ABDC I got these specs from the factory manual) upon installation of an after market cam it is best to use a deg wheel to check that the cam falls into these specs you would be surprised how often an after market cam's centerline is off 3 or 4 deg +/-. So the idea of adjustable cam gears is to bring the centerline back to factory spec. If the ecu is properly tuned at this point you should have minimal to no idle isues. I've installed a few sets of 272/272 and gotten good results. Now as for advancing or retarding a cam past the centerline that depends on what the car is being used for example: advancing an intake cam for example will increase low end power and equally decrease top end power

 

I agree, but it seems the long duration of the 272s may be such that the resulting long period of overlap becomes a detriment when the cams are installed and adjusted to the factory settings. This seems to be supported by the fact that those who have tested the various cam configurations report better average power with one cam being of shorter duration (264). If the long overlap of the 272s is such that a sigificant portion of the fuel charge is being pushed through the exhaust valve, this will sap some of the factory turbo's ability to keep the system pressurized, and no ECU tuning can fix it.

However, with much area under the lobe (e.g. 272), one should be able to dial out some of the overlap, which will restore idle qualities and improve low and midrange power without sacrificing top end. This seems consistent with what those who have done this have reported. Ultimately, the single most important event is the point at which the intake valve closes, so the point at which retarding the intake valve further compromise average power is perhaps the most important to note.