Speed Density Modders Please Help!

[Daggar]

Hey Daggar, this is probably a dumb question but since my cam has 4* of advance ground into it and I advanced the base timing to 13*, have I essentially advanced my timing 17*?

What Vristang said. Two totally different animals. It could account for having less vacuum and being rich at idle and cruise, if you run into that problem with the 19s though.

For the most part, if your'e running an SD friendly cam with a stock SD EEC, you should install the cam straight up.

Just something to keep in mind if you continue to have issues.

 

[arbailey]

DAGGAR, I put the 19's in and it seemed to help, but then it happened again. You mentioned before that I should check vacuum. What type of numbers should I be seeing? Also, I plan on ordering that wideband LM-1. You said you have some nice installation pics? And can you give me more info on that vacuum line shut off? HEY! Now that I think of it, (on the stock set-up) the hose that went from the MAP sensor to the intake manifold looked like a molded hose that was larger at one end than the other. When I installed the Explorer manifold I installed a fitting in manifold the same size as the nipple on the MAP sensor so I could use a regular 5/16" (I think) hose. Could that be my problem?????????

 

[vristang]

Now that I think of it, (on the stock set-up) the hose that went from the MAP sensor to the intake manifold looked like a molded hose that was larger at one end than the other. When I installed the Explorer manifold I installed a fitting in manifold the same size as the nipple on the MAP sensor so I could use a regular 5/16" (I think) hose. Could that be my problem?????????

If it's causing a vac leak, then yes...




jason

 

[arbailey]

If it's not leaking, then it's okay that I changed the hose because vacuum is vacuum right?

 

[vristang]

Other than a leak, you just have to watch for 'kinking' of the vac lines.
This shouldn't be an issue though...
Also, the MAP sensor should be hooked directly to the manifold, but it sounds like you have done that.


Have you been able to hook up a vac gauge?

jason

 

[Daggar]

DAGGAR, I put the 19's in and it seemed to help, but then it happened again. You mentioned before that I should check vacuum. What type of numbers should I be seeing? Also, I plan on ordering that wideband LM-1. You said you have some nice installation pics? And can you give me more info on that vacuum line shut off? HEY! Now that I think of it, (on the stock set-up) the hose that went from the MAP sensor to the intake manifold looked like a molded hose that was larger at one end than the other. When I installed the Explorer manifold I installed a fitting in manifold the same size as the nipple on the MAP sensor so I could use a regular 5/16" (I think) hose. Could that be my problem?????????

Pics sent. The problem that you've described should not be the result of a smaller vac line. It still sounds to me like your fuel is richening up faster than the motor is spinning up. That's a reverse condition of what running a smaller vac line should cause. Check and recheck your TPS.

 

[arbailey]

vristang - I have not hooked up a vacuum gauge yet, I am waiting to borrow one.

daggar - It seems like the computer is startig to learn. It's happening less and less the more miles I put on it. I'll check the tps, and vacuum though.