how to know if i run too lean?

[static]

Hey guys

I just testdrived my S50 swap yesterday for the first time.
Due to certain reasons, I am running 413 DME with a custom chip for M50 with S50 cams. But since real S50 got 0.5L more volume it probably runs lean.
I understand that the close loop corrects the ratio to a certain point, but is that enough for safe operation?
I use 94 octane gas

Are there any methods to determine if i run lean short of going to a dyno? (i will eventually go to dyno, but not before i take care of all kinks)

Thanks
Alex

[Mr. M-Tech]

Hey guys

I just testdrived my S50 swap yesterday for the first time.
Due to certain reasons, I am running 413 DME with a custom chip for M50 with S50 cams. But since real S50 got 0.5L more volume it probably runs lean.
I understand that the close loop corrects the ratio to a certain point, but is that enough for safe operation?
I use 94 octane gas

Are there any methods to determine if i run lean short of going to a dyno? (i will eventually go to dyno, but not before i take care of all kinks)

Thanks
Alex

Do you hear any pinging or detonation on the top end @ full throttle? Is the motor misfiring @ high rpm. If so you better loose the 413 M50 chip & find a 506 or risk some serious damage to your S50. Even though the M50 chip is calibrated to run with s50 cams, It doesn't change the general nature of the 2 motors. The power bands are still different: timing, torque, hp, fuel curves etc...

[Erick]

Check your spark plugs.

[permit]

When you let off the gas, you'll usually be able to hear rumbing sounds from the muffler.

[equate975]

Im in the same boat, although I have a chip tuned for all my mods I want to make sure im getting the correct mixture incase something is out of whack.

http://www.scirocco.org/tech/misc/afgauge/af.html

If you wanna make a quick dirty AFR gauge

I think you can hook a volt meter up to the O2, but I dont know if the O2 sensor is linear or not. (Although I have been told by people just to use a volt meter to measure my AFR)

I plan just to get an autometer gauge just to hook up for the first couple weeks of driving to make sure something dosnt go wrong.

Something is happeneing on my engine, sometimes I press the gas and nothing happens, jerks around, or something. I need to see my AFR.

[mspiegle]

Im in the same boat, although I have a chip tuned for all my mods I want to make sure im getting the correct mixture incase something is out of whack.

http://www.scirocco.org/tech/misc/afgauge/af.html

If you wanna make a quick dirty AFR gauge

I think you can hook a volt meter up to the O2, but I dont know if the O2 sensor is linear or not. (Although I have been told by people just to use a volt meter to measure my AFR)

I plan just to get an autometer gauge just to hook up for the first couple weeks of driving to make sure something dosnt go wrong.

Something is happeneing on my engine, sometimes I press the gas and nothing happens, jerks around, or something. I need to see my AFR.

If you're worried about it and just need to buy time before checking the AFRs, then just use high octane gas. 94 is probably good enough to hold you over. As long as you hear no pinging at your torque peak, you're probably ok for now. Get a wideband tester!

[equate975]

OT: But does anyone know the procedure for testing the 540/Euro HFM? Im just going to go through the list of what could cause a bad AFR if mines messed up.

[permit]

You can put the HFM on even without a chip for it. If it's a working HFM, then the engine will idle kinda funny, and it won't run like it should, but it'll still be driveable. If you have an HFM that is dead, it will feel like your motor has 30hp, will react very very poorly when you give it some gas.

[KangamangusDriver]

Read your plugs, cardboard brown=good

any lighter than that you are running lean/hot.

Black=running rich.

That will give you a rough idea before you burn up an engine.