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-   -   Aftermarket Starter/ Relocated Battery (https://www.rx7club.com/1st-generation-specific-1979-1985-18/aftermarket-starter-relocated-battery-606063/)

Hyper4mance2k 12-16-06 05:52 PM

Aftermarket Starter/ Relocated Battery
 
Okalie doakallie. So First question is where are you guys grounding your batteries when you relocate your battery? I'm thinking mine is not sufficiant and I'd like to hear or preferably see more options. Secondly high compression muscle cars run aftermarket starters that spin faster than factory to get the cars to start. Does anyone kow if one starter is any better than another for our cars. From my searching it seems that all the SA/FB starters are 1.2kW 11 tooth. though the auto tranny starter is 1.7 or 2 kW 14 tooth. Why do they get the better starter? WTF!!!

85 FB 12-16-06 05:57 PM

Yeah, sucks that only small and big blocks get those nice high-torque mini-starters. That, I can't help you with. But, as far as grounding, from what I've seen, I can only tell that anywhere on the car's body is good. I'm looking to relocate as well and IIRC, the shorter the ground cable the better. The car's body is pretty much formed with the frame isn't it, so that should be acceptible for grounding, right?

Well, my guesses are usually off so watch someone come in and point us both in the right direction.

Rx-7Doctor 12-16-06 06:01 PM


Originally Posted by Hyper4mance2k
Okalie doakallie. So First question is where are you guys grounding your batteries when you relocate your battery? I'm thinking mine is not sufficiant and I'd like to hear or preferably see more options. Secondly high compression muscle cars run aftermarket starters that spin faster than factory to get the cars to start. Does anyone kow if one starter is any better than another for our cars. From my searching it seems that all the SA/FB starters are 1.2kW 11 tooth. though the auto tranny starter is 1.7 or 2 kW 14 tooth. Why do they get the better starter? WTF!!!

The ones they are using in the motors you have mentioned are what is refeered to as gear reduction starters. and are generally used in high compression motors.

We have no need for such a starter. The key in cranking is in the amp rating of the battery and more importantly the condition and type of ground cable used.
The A/T require a higher amp motor to compensate for the mass of the torque converter.
You could always get the A/T starter and swap out the starter drive.:)

Hyper4mance2k 12-16-06 06:03 PM

I'v allready relocated the battery, just thinking i need to relocate the ground since my positive battery cable gets warm to the touch when caranking, and it cranks as slow as a 14:1 comp 454. All new wires 8G power and 6G ground. New optima yellow top FD alt. alt is good battery is good and it cranks as slow as a big block. It rarely hot starts I have to let the car sit for at least 10 minutes before it will hot start...

Rx-7Doctor 12-16-06 06:13 PM

Ground wire is too small. You need either a 1 or 2 gauge cable. Some guys even use 1/0 or 2/0 and even welding cable for the grounds. Where is the battery located?

85 FB 12-16-06 06:18 PM

^ I agree, I was about to say that the guage wire you're running right now is way too small. I was also going to suggest at least 1 guage. Check out Summit for lots of nice looking cables. :)

http://store.summitracing.com/egnsea...42&D=%2D109442

Rx-7Doctor 12-16-06 06:30 PM

You can go down to most of the local Napas and have them build you a custom cable on the spot.

85 FB 12-16-06 06:48 PM

I'd prefer to go with Summit. The NAPA near me is a joke, they don't have squat for parts.

Dan_s_young 12-16-06 06:59 PM

For my car I was thinking of going with this...

http://store.summitracing.com/partde...0&autoview=sku

Hyper4mance2k 12-16-06 07:01 PM

I've got plenty of wire sittin around infact some 1/0 in th car on the passenger seat. Alot of good it's doin me there. LOL! The battery is behind the passenger seat.

Rx-7Doctor 12-16-06 07:06 PM

You could just run the cable out the bottom where the fuel pump wiring grommet is and then attach it to the same mounting point that it was stock. Which is thru the long upper starter bolt facing towards the front side of the bellhousing. You could also run another ground strap from one of the engine irons to the frame.

85 FB 12-16-06 07:09 PM

Is it true that the shorter the ground cable, the better? Or, if you have a really thick gauge, such as 1/0, that you can go longer without worrying about current drop? Okay, on that last part I was grabbing at words with "current drop" as I have no clue if that's what the ground cable helps with. :(

Rx-7Doctor 12-16-06 07:15 PM


Originally Posted by 85 FB
Is it true that the shorter the ground cable, the better? Or, if you have a really thick gauge, such as 1/0, that you can go longer without worrying about current drop? Okay, on that last part I was grabbing at words with "current drop" as I have no clue if that's what the ground cable helps with. :(

The shorther the ground the better with the stock cable. Using heavier cable lessens the "Voltage" drop as it is refeered to. You were close. :)

GavinJuice 12-16-06 07:55 PM

take note of this, that the number ONE ground is to the alternator HOUSING. Now on our alternators there isn't anywhere to ground to the housing, but it's grounded to the engine block. SO Battery to ENGINE BLOCK, Battery to FRAME, and even BLOCK to FRAME.

Everyone should read this big post from the the12volt http://www.the12volt.com/installbay/...496&PN=1&TPN=1

When i read that the altenator housing is "absolute ground" it completely makes sense. You'll see it under NOTE in the first post.

Also Mad Scientists post on the second page is a good read, it proves why it is such an important ground.

If you've ever browsed through the site, or are an avid car audio enthusiast you'll see people with problems of noise coming through their speakers from the alternator or some other source. A common answer is to run a ground from the amp all the way to the battery. The answer of grounding the alternator housing to battery AND frame eliminates that problem.

dj55b 12-17-06 01:24 AM

thats some good info up there thanks for that .

Kentetsu 12-17-06 03:09 PM

Yeah, I'd say it is a wiring issue rather than a starter issue. With the low compression of the rotory engine, a high performance starter should not be necessary.

However, two other things I can think of that might contribute to the problem are timing and low compression....

Hyper4mance2k 12-20-06 10:57 PM

that's one thing I've never understood though. Poeple say hot start issues mean youve got low compressin, but I was sure that compression raises when the engine is at normal opperating temp. and timming should be fine locked dizzy L@10*BTDC and T@2*BTDC (remember i'mturbo blowthrough too...)

Kentetsu 12-20-06 11:11 PM

Yeah, I've never understood that either. Any chance that it might be an urban legend?

Whenever I've had the situation where it starts easily when cold, but cranks forever when hot before it starts, it has always come down to timing. Maybe not in your case, but I throw that out there as a suggestion whenever I hear those symptoms mentioned. Good luck...


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