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-   -   Wanting to Make My Starter Stronger??? (https://www.rx7club.com/1st-generation-specific-1979-1985-18/wanting-make-my-starter-stronger-894532/)

teddyrx2 03-25-10 04:29 AM

Wanting to Make My Starter Stronger???
 
Has anybody here done this? The stock starter is ok for what is/they do...But I'm wanting to repalceand rebuild my worn out starter, and replace the needed parts inside to make it stronger, and more torque-ier for quicker stronger spin during cranking to start it, instead of the slow one it has now...

I know i have to change the brush's
What about the Magnets?
Or the motor its-self?

If so where can i find these parts?

If they sold high torque starters for our 7's i would buy one, but they don't, so i have to rig something up to make it work...Or my other option is to buy a high torque starter for another car through jegs or something, fab a mounting bracket for the starter to the tranny, and call it a day, but thats too much money right now that i don't really feel like spending...

thanks for the feed back and help...

orion84gsl 03-25-10 10:14 AM

Your best bet is to call a shop that rebuilds starters and ask what is required to make it more powerful.

851stgen12a 03-25-10 10:48 AM

If you have a weak turn over, maybe you should look at your power supply cable. make sure its in good shape..... The rotary's are so super easy to turn, they shouldn't need and extra torque.... I dont think so that is ;)

mar3 03-25-10 11:13 AM

I'll have to search for it but I did a tech thread a long time ago that gets all the juice going through the starter which makes a tremendous difference in starter power when starting your beast up.

It makes modifying or upgrading from stock a non-issue.


:cool:

DivinDriver 03-25-10 11:19 AM

Torque in an electric motor is directly proportional to power consumed in watts, which in turn is volts times amps.

Needless to say, your battery has to be able to provide sufficient amperage, so battery condition and spec plays into it.

You're limited to the battery supply voltage (you can't up your total battery voltage much without reworking your entire electrical system!), so your easiest path is to decrease resistance everywhere you can, to deliver maximum current flow thru the windings. Heavy cables, low-resistance connections throughout, clean tight brushes making high-conductivity contact, smooth polished commutator.

Beyond that, you'd be looking at much more complex operations, like getting the armature re-wound to provide a stronger magnetic field, or trying to mate a different motor to the gearhead while still making it fit in its mounting position.

Looking at the spec section of my FSM, it appears that the Automatic starter (at least for the SA's) was a more powerful unit than was the one for the Manuals; 2kW compared to 1.2kW for the Manual cars. 15.9ft-lb torque versus 6.6, and it's free-run speed is 1000 RPMs higher... considerable difference there.

I've no idea what might be required to cross-fit an auto starter into a manual car, but that might be a place to start looking.

Stevan 03-25-10 12:23 PM

I have what I believe to to be an S4 auto starter in a 82 12a manual trans, bolts up, and works great.
As mentioned earlier, a fat supply will make a big difference.

Jeff20B 03-25-10 01:28 PM

Stevan, you probably have an FC manual starter. If FC auto trannies are anything like FB, the starters are way different.

teddy, you want to look for an '84-'85 starter. The gear is such that it spins the flywheel a little quicker without loss of torque. I've swapped a couple of mine over to the '84-'85 type and noticed the quicker cranking speed. Faster starts, even on tight rebuilds.

Kentetsu 03-25-10 08:18 PM

Start with new battery cables, and you will probably find that your starter works just fine. :)




.

mar3 03-26-10 01:15 AM

Here you go...no pics, though... :(

The Starter Bolt Trick

:cool:

installer67 03-26-10 01:31 AM

I upgraded my battery to an Optima red top, installed a new positive battery cable, new negative to starter bolt and from there to chassis. It was an amazing difference. Starter spins quick and strong, all electric are faster, lights are brighter. A thick quality wire for positive lead, and equal for the negative and clean contact points are the key. Add more juice from the stronger battery and your electricals just got steroids! LOL

teddyrx2 03-26-10 04:22 AM

thank you all for the input...

but i have upgraded the bat, replaced the bat to the rear and re-ran all new cabs and fatter...but that f#*king starter still cranks slow...Its also a 84-85 starter and i have also used the 85 gsl-se...Im getting tired of this lol...

thank you tho for the input...

devine, you must be a electrical engineer or something man...you know your $hit...

Should i also upgrade the alternator wire to be fatter and thicker as well?

if i decide to upgrade the cabs again what gauge?

Also:

Organization is key.

--------------------------------------------------------------------------------

What you need:
135mm long x 1.5 thread pitch bolt
Two stock positive battery cables
Various wrenches to remove starter and battery cables
Battery maintenance tools (Terminal cleaner or brush, grease)

Go do it:
1.) Remove lower starter mounting bolt.

2.) Obtain replacement bolt (135mm long x 1.5 Thread pitch)

3.) Disconnect both cables at the battery.

4.) Attach stock Positive cable to replaced lower starter mounting bolt and negative battery terminal. Remove section that goes to the fusible links. Attach that to the frame near the battery.
5.) Use new positive battery cable to connect Positive battery terminal to the starter solemoid.

6.) Be sure battery terminals are cleaned and tight, coat lightly in grease.

7.) Enjoy easier starting, improved performance, and more available electrical power.
On number 4? What the hell are you guys talking about?

Stevan 03-26-10 11:00 AM

Use the original + cable as the new ground to the starter.
The fusible link wire remains connected to the fusible links, but the other end is connected to the + batt terminal with the new + wire from batt to starter solenoid.
Not mentioned is you need a cable from batt neg to the frame, unless I missed it?
If you have all new wires this is no use to you, it's just a way to save a little money and effort.

Jeff, I think you're right about the starter. I have 2 s4, or s5 starters, and thought they were both autos, but they're different. One will not fit.

Jeezus 03-26-10 11:34 AM

Also to throw this little FYI in there:

When you replace your battery cables, look for welding cables. They can be found in the same
gauge as battery cables but with more strands inside them.

Stevan 03-26-10 11:43 AM

Yeah I used them on my F-150, worked great. Been on the truck for 12 years.
I was watching Two Guys Garage one time, and they said you don't want to use them, they didn't say why.

mar3 03-26-10 02:19 PM


Originally Posted by Stevan (Post 9894503)
Use the original + cable as the new ground to the starter.

Thanks...when you go to physically do this trick, it makes perfect sense.

Crazy, cursing teddy, I had no choice but to kill that part...lol



:cool:

Super82 03-27-10 11:48 AM

If your's is really that slow there's probably something else wrong. I have a stock 82 starter hooked up to a miata battery. It turns slow, but it can start the car in just a quick flick of the key.

teddyrx2 03-30-10 02:23 AM

Well the starter was bad to begin with...

Gunna take out the old one replace it with a new one, do the re-wire trick, and see what happens...thank you guys for the help...

Jeezus 04-11-10 06:59 PM

Bump, how'd it do Ted?


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