starter wiring.......

[vso737]

http://s198.photobucket.com/user/vso737_2007/media/starterwiringSKETCH_zps1580a9f0.jpg.html][/URL]

Can someone give advise on this sketch??

Am I barking  up the right tree here?

I'm trying to install a RELAY with my SBC starter.

Thanks a bunch,
Mike[/img]

[wayne petty]

except you are using a GM starter with a solenoid on top..

run a piece of solid 12 gauge from around the top post to the S terminal on the starter...

this is the safest wiring system to use with headers.. as the cable to the starter ONLY has power when the relay is engaged...


you can use the I terminal on the ford starter relay.. as it has the same function as the R terminal on the gm solenoid..  this way.. there is only the starter cable going between the relay and the starter..


i did this with my 66 GTO.. mounting the ford solenoid high up on the firewall directly over the starter... with a 2 gauge wire down to the starter and the jumper wire..

this allowed me to unbolt the starter cable at the solenoid.. tie a string to the end of the wire and drop the other end under the car.. i was then able to climb under the car.. take out the starter bolts and drop the starter and cable in a quick motion..  then just untie the string from the end of the starter cable..   when reinstalling.. i tied the string back on.. pulled the other end to pull the cable up while i pushed the starter into place..

i also ran dual car batteries to get this motor to crank every time.. hot or not..  2 gauge cable all over the place..

now.. to answer your questions..

there are NEVER fuses installed where you have indicated...

there are fusible links installed between the alternator output and the starter relay..  depending on the alternator output..  

there are also fusible links installed between the starter relay and the wiring that goes into the car...

fuses are FAST blow..

fusible links are SLOW blow and will handle overloads for short periods of time..

fusible link is sized 4 gauge numbers smaller than the circuit it protects.. usually a 5 or 6 inch length of fusible link..

so an 8 gauge wire uses 12 gauge fusible link
a 10 gauge wire uses 14 gauge fusible link
12 gauge wire uses a 16 gauge fusible link..
14 gauge wire uses a 18 gauge fusible link..

any circuit smaller than 14 gauge should be fused with conventional fuses..

to tell if you need a thicker wire for a circuit.. use a voltage drop test with all the items using power on that circuit turned on..  0.02 volts or 0.03 volts between the item end of the wire and the positive battery when the load is active..

if you get more.. then go up a gauge