ZZ42Fast

iTrader: (2)

Hi guys,

Running a lb9 with powermax 2032 cam, Bosch injectors and just fitted a Procharger with 2 core intercooler. I use the supplied FMU and additional fuel pump.

I hear that as it's intercooled, I can leave timing stock @ 6 degrees. As the cooler air means it can handle the EST timing advance.

I panicked a bit before and ordered the MSD BTM unit that senses boost and pulls timing. I have recently heard that these can be unreliable. Worry is that if it fails it could cause damage.

So question is- shall I just stick to stock or should I fit the MSD?

Thoughts/ experiences please?

customblackbird

iTrader: (15)

Depends on your experience with MSD. I've had both MSD stuff and Mallory and I prefer Mallory. But MSD has bough Mallory lol so it sucks.

I've heard and it's well known that the MSD digital CD boxes have high failure rates, their analog stuff is great. I had a Mallory 685 on my car for years and it worked flawlessly. I just sold it with my EFI to my brother and it's still working. It has a MAP sensor to sense boost for timing etc and I would trust it. You won't find anything MSD on my car unless I have no choice.

Anything that senses boost has a MAP sensor built in. Doesn't matter if its stock vs MSD or pertronix etc. if the sensor fails you got problems. But OEM has the most engineering invested and money vs even a big company like MSD.

I'm in the process of my supercharger on a 5.3 but going stock PCM with MAP sensor. My backup is a innovate PSB-1 which has a boost/map sensor for boost readings along with WB02 together and I've wired it to kill 4 of my 8 injectors if it senses a boost/fuel issue and out of the perimeters I've set.

Nothing u can do about timing except knock sensors. Too much timing will create knock or detonation and the knock sensors should pick it up and restard the timing.

Orr89RocZ

iTrader: (20)

In theory it should be fine. You'll want to pull atleast 1.25 deg per psi. If the btm worries you just set base timing retarded however many degrees you need to cover your boost

ZZ42Fast

iTrader: (2)

Thanks for replying guys. I'm not if I need to pull timing or not though. Being intercooled some say no need?

Orr89RocZ

iTrader: (20)

No you will def need to pull timing even on 5-8 psi

customblackbird

iTrader: (15)

I agree with Orr, you will need to pull timing really no matter what with FI. Inter cooling and meth/injection just allow you to run more than you normally would retard which essentially gives/lets you keep more power.

ZZ42Fast

iTrader: (2)

Thanks, thats good to know

86CamaroDan

Though i cant speak for the boost retard, Ive had two MSD boxes, and one stand alone MSD distributor go bad in 6 years. I went to a stock HEI8 setup controlled by megasquirt and havent looked back since, overall drivability is way better too. Like blackbird says,

no new tires

- edit: NVM