Team Camaro Tech banner

LS swap Starter wiring

14K views 8 replies 6 participants last post by  Shannon4570 
#1 ·
Hey guys, I just got off the phone with Mark from MAD Electrical. All I can say is holy cow, this was a long conversation for a very small order LOL. He mentioned you MUST use a relay (Bosch type) when using a "Ford type solenoid" because you can NOT install the purple ignition wire (original purple wire) to the starter "S" terminal and from the "S" terminal back to the "Ford type solenoid" in the trunk. You can't run both solenoids parallel. I'm pretty sure I read most of the guys on here doing LS swaps doing exactly that (NO relay). Am I mistaken ??? :clonk:
 
#2 ·
I'm sure he's was telling you this due to the wire length and current draw of the two devices. If you can find the actual load at 12VDC of both you probably see that. Also voltage drop may occur depending on gauge.

I still don't understand the Ford relay in the trunk. You have a charging wire going to the trunk that's hot right? It still needs to be at least an 8 gauge minimum. If you short that out the fire will be just as big as if it was 2 gauge or bigger. Now with the solenoid wire you have yet another wire that's hot running front to rear while cranking. Just say'n, it's extra stuff you don't need, three wires when you only need one. Resetable circuit breakers aren't that expensive.

In our 2015 Z/28 the battery is in the trunk and the heavy gauge wire runs straight up to the engine bay, hot all the time. No solenoid or anything other than a maxi-fuse at the battery.

I was able to run the purple wire in the factory harness directly to the starter, but that was it. I didn't have the other solenoid. No issues.
 
#3 ·
Thanks Garth. I hear what your saying. I went with what I thought the majority of guys were doing. The lengths of the wire have nothing to do with the solenoids running parallel, the issue appears to be the 2 solenoids, 1 in the trunk, and 1 on the new starter. My batt cable will be only hot when cranking. The 8 gauge from the "Ford" solenoid in the trunk to main load lug on new GMPP fuse box will be Hot all the time. This 8 gauge is protected with a fusible link.
 
#4 ·
Mark at MADD is wrong in this case. Smart guy a little over the top will tell you how to build a watch when you ask what time it is.

You can run purple the the F solenoid and from the solenoid to the starter S terminal. The solenoid is basically a relay itself.

I gave done it this way on several cars and for 5 years with no problems.

You can also pigtail at the S terminal on the starter and go from there to solenoid to close when ignition is engaged so the Batt wire goes hot when cranking. Concern over wire length is not factor. Geez the wire is like 8' long with #10 and 12V DC. No real voltage drop
 
#5 ·
Mine is wired just as John's above.... yes, the starter does run an extra second....I'm OK with that.

Been this way for years when I did the trunk mount even before the LSx ;)
 
#6 ·
I relocated the battery in the trunk and did the solenoid deal, not sure it was necessary but what the heck, it sure looks cool. I used the purple wire to trigger both solenoids and have had no issues. I originally ran a jumper on the starter but couldn't stand the sound the starter made as the voltage bled off the big wire from trunk. I don't think you need a relay.
 
#8 ·
Thx guys. My head was spinning after that phone call to MAD Electrical. John, to say "Over the top" is an under statement!! LOL. I think I was able to get 2 words in during what turned out to be a 30 min conversation. I only was placing a small order!!!! Thx again everyone.
 
#9 ·
Drumming up an older thread here but want to confirm I'm only moderately confused. I have both my trigger wire from Quickcar solenoid (refuse to say Ford) and the purple wire from ignition switch > clutch safety switch going to the pigtail for the starter solenoid. I am pretty certain this is correct but just want to double check. I think I just have an extra wire because I opted to include the clutch switch.

Does this sound correct?
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top