Loudpipe

iTrader: (11)

So I just got my 408 in the car and ready to fire up...no dice. After searching all the threads I could find I figured out I had no spark..pulled All the plugs and then tried it. I had plenty of spark...put 3 plugs in, a battery charger, and tried it. No spark again. It appears that I have the box that requires 200 rpm of cranking before it will send a signal. How big a battery (cranking amps) do I need to make this mother hump?

S10xGN

iTrader: (11)

Try removing all advance (zero it out) below 500 RPM, see if that'll do it. If not, check your wiring for corrosion and the battery for charge. You could put a jumper battery on it too...

ZONES89RS

iTrader: (25)

I have done many swaps and never had a issue. But, if you are pushing higher compression you may need a better starter than factory.

wildcamaro

iTrader: (15)

Check those grounds!!! I had a hell of a time, hook it up to lap top and verify you have at least 150-200rpm on crank, but check grounds!

Loudpipe

iTrader: (11)

Didn't have any issues when I was running a stock short block 6.0 last fall. Now I got this mess.

Pop N Wood

iTrader: (1)

Given the lack of other options I always hate hearing about the MSD boxes not firing with low cranking speeds. You might try contacting MSD and work with them. Sometimes they can reflash the box or will even send you a new one.

If you do need to upgrade starters I run an MSD starter. Price isn't too bad and that sucker cranks. Probably don't want to hear a suggestion to buy another MSD product to make up for another MSD product, but never the less.

michael37

iTrader: (3)

I have had the exact same problem. twice. and read about others having this problem. don't worry, i have the answer for you. The problem is, your not cranking it fast enough to SYNCRONIZE the box with the motor. i tried brand new batteries wired in parallel and still no luck. i had spark with plug out of motor but not when they were in the motor. i tried sensors, which wasn't the problem. i called MSD (which has great customer service) and they sent me a new box and new harness. still had the problem. finally i gave in and did what a few on here talked about doing (which i didn't want to do) was put two batteries in series (24 volts) and try it. it fired up in 1 second of cranking. so i wired the ignition to be 12 volts and the starter to 24 volts. i was just scared about buring stuff up, but i figured if i only wire the starter to 24 volts then thats all that would burn up if it did. and it didn't. it literally took 1 sec of high speed 24 volt cranking and it fired up and syncronized. now 12v is all it takes to start it. i can almost gaurentee you this is your problem!! trust me i tried everything before resulting to 24 volts to the starter. Bottom Line, your not cranking fast enough.

if you need help wiring it up shoot me a message and ill help

wildcamaro

iTrader: (15)

I had the same issues your talking about...if you hook up a laptop to the MSD and crank you can verify that your crank sensor is getting a signal by verifying that you got the necessary 150 rpm crank...makes it easier than trying to run as splice into the crank sensor reference voltage that's for sure!

Loudpipe

iTrader: (11)

It's alive.....I took 2 short cables from the starter and a ground to the head hooked them to a tractor battery I had setting on the strut tower and ran the rest of the electrical from the 12 volt in the trunk. I put the battery booster on the battery up front....it cranked for 3 seconds and fired up. Like you said now the regular 12 volt in the trunk starts it just fine. Thanks for the input guys. I will try to post a thread with a link tomorrow...this new Tick Performance cam makes this thing sound like a pro mod!!!