When I originally built my LS1 conversion car, I didn't add a relay for the starter solenoid (to save the ignition switch). I can retrofit one quite easily, however what rating of relay is really necessary? I have a 30 amp, which would seem to me to be plenty good to activate the solenoid. Thoughts?

Andys

My current hot start relay is 30 amp. Never had a problem

I have a 15 amp fuse on mine. I wouldn't go higher than that. Make sure your starter and solenoid are in good working order. If the solenoid hangs up it'll blow the fuse when that happens. I put the fuse mounted on the firewall. If it does blow I don't have to crawl underneath a hot engine and heat exchanger to change it.

Personally I'll always be in the Ford solenoid (relay) camp.
Always works, fast, cheap, no cutting of wires or drilling holes.
Been using them for almost 30 years, all my aircooleds have one.

I like the Ford relays also. Andy, you have to perfect it before you help me with mine!

All my starter troubles ended when I did the Ford relay "upgrade".

This thread was helpful. Especially the wiring diagram...

http://www.914world.com/bbs2/index.php?showtopic=259055

Ditto, except I used the Pelican kit with the Bosch relay. I know a lot of folks like to try to get to the bottom of the issue, but in my mind the root cause is a poor electrical design. Let this relay handle the amps for the solenoid, and use that crappy wire and ignition switch to just activate the relay.

Another option: http://www.amazon.com/gp/product/B001COAX78

BTW, if you go with the above or Pelican's (I think it's the same thing) put that fuse holder somewhere you can easily get to it. I popped mine one night this past year and could not change it because I was in nice clothes. It's now mounted in the engine compartment.

I think the benefit of the Ford style, is that you don't need anything else to mount it. It has tabs integral to the body.

Otherwise 30 amps is plenty. 8-10 Amps comes to mind when thinking of the Solenoid, but I cant be sure.

Since you're probably going to re-wire your entire LS6 conversion car, a GM BCM may be your best solution, as it will upgrade your electrical system to modern standards. The BCM includes relays for the starter, headlights, horn, etc as well as the pertinent fuses.

I agree that the Ford relay beyond bullet proof!

Thanks for the replies!

I hadn't considered a fuse, so yes I'll add one (I have an open slot in my power distribution fuse block). I would think a 10 or 15 amp fuse would be good enough.

Andys

Why do you need a fuse?
To gain two more potential fail points?

Here's my setup: I have an 6 position distribution fuse block (two rad. fans, fuel pump, OBD2) with two open slots, fed by an 8ga wire that's protected by a 50 amp circuit breaker. I think it's a good idea to protect the solenoid wire with a fuse to avoid drawing up to 50 amps should a short or overload occur. The the fuse block will be my power source for the relay/solenoid wire.

Andys

OK....I just take power from the large battery cable + on the solenoid.


This pic from several years ago and I do a better a crimp job* but it shows the wiring well.
Like I said, not a single OE wire is cut or any holes drilled.



This shows how I bolt it to the lower starter bolt.
Be careful bending the bracket so you don't stress the solenoid housing and note that the solenoid does ground on the bracket



*I know the crimps are messy this wiring was either one of my first attempts from the 80's or someone else's work. I do remember grabbed quickly at the time just to show how I wire and mount the solenoid.
I remove the yellow plastic, crimp it correctly and shrink tube the ends, Plus on the ford small post I use a ring spade adapter like below when I do it.
BTW that is the 901 (911) with 914 gearing that is in my '67 VW bug, in case you are wondering.