Power...
07-21-17, 04:22 PM
#1
Full Member
Thread Starter
Power...
Hello,
In the middle of a few jobs on my Rx7 for the last while....well, I need more electric power....I only have a 55 amp alternator.... I have seen people installing 100 & up to 130 AMP alternators ....on FB's & this is what I need....hopefully a 130 AMP unit that is easy to install....
Does anybody have any experience with this? or can point me in the right direction?
Thanks.
In the middle of a few jobs on my Rx7 for the last while....well, I need more electric power....I only have a 55 amp alternator.... I have seen people installing 100 & up to 130 AMP alternators ....on FB's & this is what I need....hopefully a 130 AMP unit that is easy to install....
Does anybody have any experience with this? or can point me in the right direction?
Thanks.
07-21-17, 10:47 PM
#2
ancient wizard...
Easy is relative...Fc oe alternator was good for 70 amps. Fd oe alternator rated at 90 amps.
All will essentially bolt in place of original alternator
There are rebuilders that offer higher output alternators up to 130 amps but quality and warranties vary as do prices. Have done a bit of research on different products,have some recommendations if interested. For my purposes i purchased a used Fd alternator and rebuilt it with new components rated at 130 amps,load testing showed output of 141 amps and able to put out 75 amps at idle speed.
Consideration must be given to upgrading wiring for larger alternator. When i upgraded my charging system i upgraded to a 2nd gen underhood fusebox to give me more options for future additions to electrical system. This is not necessary for your upgrade,but i do recommend upgrading your underhood fuselinks and stereo equipment will necessitate heavy duty wiring to supply needed current for amps and such from/to battery.
Regarding fuselinks,a common upgrade is to replace them with 2nd gen fuses which plug in directly to where fuselinks are.
Some thought needs to be given to the drive belt. Trying to drive a hi-output alternator with one v-belt doesn't work well long term. Belt slippage will cause grease in alt front bearing to get cooked leading to premature failure. Trying to increase belt tension to compensate puts excessive load on eccentric shaft bearings,not good. Need to run dual sheave alt.pulley to run dual drive belts. If you're still running emission controls with an air pump it is a bit more complicated.
Aside from upgrading size and fusing of alternator output wire there is a small modification to exciter wire harness to run Fd alternator with Fb wiring harness.
Some pics.
All will essentially bolt in place of original alternator
There are rebuilders that offer higher output alternators up to 130 amps but quality and warranties vary as do prices. Have done a bit of research on different products,have some recommendations if interested. For my purposes i purchased a used Fd alternator and rebuilt it with new components rated at 130 amps,load testing showed output of 141 amps and able to put out 75 amps at idle speed.
Consideration must be given to upgrading wiring for larger alternator. When i upgraded my charging system i upgraded to a 2nd gen underhood fusebox to give me more options for future additions to electrical system. This is not necessary for your upgrade,but i do recommend upgrading your underhood fuselinks and stereo equipment will necessitate heavy duty wiring to supply needed current for amps and such from/to battery.
Regarding fuselinks,a common upgrade is to replace them with 2nd gen fuses which plug in directly to where fuselinks are.
Some thought needs to be given to the drive belt. Trying to drive a hi-output alternator with one v-belt doesn't work well long term. Belt slippage will cause grease in alt front bearing to get cooked leading to premature failure. Trying to increase belt tension to compensate puts excessive load on eccentric shaft bearings,not good. Need to run dual sheave alt.pulley to run dual drive belts. If you're still running emission controls with an air pump it is a bit more complicated.
Aside from upgrading size and fusing of alternator output wire there is a small modification to exciter wire harness to run Fd alternator with Fb wiring harness.
Some pics.
07-24-17, 03:39 PM
#4
Full Member
Thread Starter
thanks Guys.....;its of good info here....thx.
I will make the 'big 3' conversion...( where You put bigger wires (4ga.) on the alternator to battery, engine ground (batt to engine block) & & there is another ( I can't remember at the moment) perhaps starter to battery???
Also I will run 4 ga from the battery to a power distribution block that will step down from 4 ga to 6 or 8 ga. at the amps..
I didn't know about the usable links & I will look into that (upgrading to FC style) so hopefully I won't have a problem there..Thx
My car already has the twin belt alternator pulley Upgrade....when I bought it.... & no smog/air pump installed either. so, I should be good there....
I hace a good local alternator guy.... Perhaps I can buy & bring him an FD alternator like You did (GSLSE4ME) & have them rebuild it for maximum power output....
I really just want an alternator that fits like factory with out too shoehorning, grinding & cussing...LOL...
However, I am going to run over 600 watts stereo, get some extra fog lights, more interior lights, ....etc....I live in Florida....so lots of times (In the rain) I will have all lights on , A/C on, windscreen wipers, stereo on, & etc whatever other BS I'll have going in there....
SO, I guess I have a plan.....get an FD alternator (used) & have my guy tune it up for maximum performance!!! I know You can have a kick *** stereo...& if You don't have enough juice to run it.....You will be unhappy...LOL...
Thanks
I will make the 'big 3' conversion...( where You put bigger wires (4ga.) on the alternator to battery, engine ground (batt to engine block) & & there is another ( I can't remember at the moment) perhaps starter to battery???
Also I will run 4 ga from the battery to a power distribution block that will step down from 4 ga to 6 or 8 ga. at the amps..
I didn't know about the usable links & I will look into that (upgrading to FC style) so hopefully I won't have a problem there..Thx
My car already has the twin belt alternator pulley Upgrade....when I bought it.... & no smog/air pump installed either. so, I should be good there....
I hace a good local alternator guy.... Perhaps I can buy & bring him an FD alternator like You did (GSLSE4ME) & have them rebuild it for maximum power output....
I really just want an alternator that fits like factory with out too shoehorning, grinding & cussing...LOL...
However, I am going to run over 600 watts stereo, get some extra fog lights, more interior lights, ....etc....I live in Florida....so lots of times (In the rain) I will have all lights on , A/C on, windscreen wipers, stereo on, & etc whatever other BS I'll have going in there....
SO, I guess I have a plan.....get an FD alternator (used) & have my guy tune it up for maximum performance!!! I know You can have a kick *** stereo...& if You don't have enough juice to run it.....You will be unhappy...LOL...
Thanks
Last edited by SKYDRIFTER350; 07-24-17 at 03:41 PM. Reason: add more
07-26-17, 11:17 AM
#5
Keep in mind; 1hp=746 watts at 100% efficiency. On a 12VDC system that's just over 62 amps per HP, & most devices are far less than 100% efficient (including alternators; average 55% efficient or less in converting mechanical to electric power).
1hp doesn't sound like a lot, but you're only starting with 100-150, losing 3 or 4 may be something to consider.
People pay a lot to get an extra 5hp out of their engine.
1hp doesn't sound like a lot, but you're only starting with 100-150, losing 3 or 4 may be something to consider.
People pay a lot to get an extra 5hp out of their engine.
Last edited by DivinDriver; 07-26-17 at 11:21 AM.
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08-05-17, 10:54 PM
#6
Full Member
Thread Starter
Thanks DIVINDRIVER.....i dig what Ur saying...I'm used to having V-8's all my life...so the GSL's 12a engine seems anemic to me in the first place...LOL....So, unless I boost this thing or do something else to dramatically increase HP output....It kinda doesn't matter to me... a few horsepower loss is acceptable to me...I want cold A/C, banging stereo & a fun little second car to spool around town...
I'd love to have it boosted with some kind of turbo...but, I'm not diving into that unless I can find someone to do the instal, tune & all that for me......for some kind of AFFORDABLE (LMAO) price .....I want to just keep it pretty simple. & once You start modifying this & that....for me it will never end....& the Rx7 is just something I don't wanna dump that much cash into ...(I'll get carried away!!)
I dump money into my bikes..... LOL...
I'd love to have it boosted with some kind of turbo...but, I'm not diving into that unless I can find someone to do the instal, tune & all that for me......for some kind of AFFORDABLE (LMAO) price .....I want to just keep it pretty simple. & once You start modifying this & that....for me it will never end....& the Rx7 is just something I don't wanna dump that much cash into ...(I'll get carried away!!)
I dump money into my bikes..... LOL...
08-06-17, 01:56 AM
#7
Senior Newbie Member
Easy is relative...Fc oe alternator was good for 70 amps. Fd oe alternator rated at 90 amps.
All will essentially bolt in place of original alternator
There are rebuilders that offer higher output alternators up to 130 amps but quality and warranties vary as do prices. Have done a bit of research on different products,have some recommendations if interested. For my purposes i purchased a used Fd alternator and rebuilt it with new components rated at 130 amps,load testing showed output of 141 amps and able to put out 75 amps at idle speed.
Consideration must be given to upgrading wiring for larger alternator. When i upgraded my charging system i upgraded to a 2nd gen underhood fusebox to give me more options for future additions to electrical system. This is not necessary for your upgrade,but i do recommend upgrading your underhood fuselinks and stereo equipment will necessitate heavy duty wiring to supply needed current for amps and such from/to battery.
Regarding fuselinks,a common upgrade is to replace them with 2nd gen fuses which plug in directly to where fuselinks are.
Some thought needs to be given to the drive belt. Trying to drive a hi-output alternator with one v-belt doesn't work well long term. Belt slippage will cause grease in alt front bearing to get cooked leading to premature failure. Trying to increase belt tension to compensate puts excessive load on eccentric shaft bearings,not good. Need to run dual sheave alt.pulley to run dual drive belts. If you're still running emission controls with an air pump it is a bit more complicated.
Aside from upgrading size and fusing of alternator output wire there is a small modification to exciter wire harness to run Fd alternator with Fb wiring harness.
Some pics.
All will essentially bolt in place of original alternator
There are rebuilders that offer higher output alternators up to 130 amps but quality and warranties vary as do prices. Have done a bit of research on different products,have some recommendations if interested. For my purposes i purchased a used Fd alternator and rebuilt it with new components rated at 130 amps,load testing showed output of 141 amps and able to put out 75 amps at idle speed.
Consideration must be given to upgrading wiring for larger alternator. When i upgraded my charging system i upgraded to a 2nd gen underhood fusebox to give me more options for future additions to electrical system. This is not necessary for your upgrade,but i do recommend upgrading your underhood fuselinks and stereo equipment will necessitate heavy duty wiring to supply needed current for amps and such from/to battery.
Regarding fuselinks,a common upgrade is to replace them with 2nd gen fuses which plug in directly to where fuselinks are.
Some thought needs to be given to the drive belt. Trying to drive a hi-output alternator with one v-belt doesn't work well long term. Belt slippage will cause grease in alt front bearing to get cooked leading to premature failure. Trying to increase belt tension to compensate puts excessive load on eccentric shaft bearings,not good. Need to run dual sheave alt.pulley to run dual drive belts. If you're still running emission controls with an air pump it is a bit more complicated.
Aside from upgrading size and fusing of alternator output wire there is a small modification to exciter wire harness to run Fd alternator with Fb wiring harness.
Some pics.
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08-06-17, 08:28 AM
#8
ancient wizard...
Yes,they will install directly in place of oe fuselinks . You'll need two 30 amp and one 60 amp. 60 amp is for the main,the 30s are for the remaining positions. Not 100 % accurate,but most are color coded" Yellow=60 Pink=30 amps. Napa,Autozone,Advance carry them.
Note: if you are planning on upgrading alternator,etc... you can do this upgrade,BUT suggest you leave all oe wiring for fuselink/fuses intact and make a separate FUSED harness from alt to battery as original alt wire gauge and fuselink/fuse is 60 amps-not heavy enough to transfer extra current developed by larger alternator.
One last thing:when converting to larger (FD) alternator...it will directly bolt in place of your original but you will need to install longer drive belts as the belt length changes due to wider alt housing. I tried several til got a pair that was correct length,i can look and see what the #s are if you'd like.
Some pics..
Note: if you are planning on upgrading alternator,etc... you can do this upgrade,BUT suggest you leave all oe wiring for fuselink/fuses intact and make a separate FUSED harness from alt to battery as original alt wire gauge and fuselink/fuse is 60 amps-not heavy enough to transfer extra current developed by larger alternator.
One last thing:when converting to larger (FD) alternator...it will directly bolt in place of your original but you will need to install longer drive belts as the belt length changes due to wider alt housing. I tried several til got a pair that was correct length,i can look and see what the #s are if you'd like.
Some pics..
08-31-17, 12:43 PM
#9
Full Member
Thread Starter
hanks GSL4ME....
IF YOU WOULD NOT MIND...I WOULD LIKE TO KNOW THE LENGTHS OF THE NEW D RIVE BELTS YOU have installed...THX...
Also, I plan on using an FD alternator I have see n on Ebay rated at 200amps all rebuilt & new inside,,for about $175.00
I don't think I can buy a used one & have it worked for that kind of money....
what do Ya think ?
HIGH OUTPUT 200AMP ALTERNATOR Fits MAZDA RX-7 1.3L L4 1993 1994 1995 200AMP | eBay
this one? any input? thx..
Sam
IF YOU WOULD NOT MIND...I WOULD LIKE TO KNOW THE LENGTHS OF THE NEW D RIVE BELTS YOU have installed...THX...
Also, I plan on using an FD alternator I have see n on Ebay rated at 200amps all rebuilt & new inside,,for about $175.00
I don't think I can buy a used one & have it worked for that kind of money....
what do Ya think ?
HIGH OUTPUT 200AMP ALTERNATOR Fits MAZDA RX-7 1.3L L4 1993 1994 1995 200AMP | eBay
this one? any input? thx..
Sam
08-31-17, 08:53 PM
#10
ancient wizard...
I'm away from home til tomorrow afternoon. I can check belt length then.
Regarding the alternator,have installed Powermax alternators on a couple of domestic trucks with some serious light upgrades and didn't have any problems with them. In load testing them they were a little shy of claimed output but worked ok otherwise. Never used one on a rotary,but shouldn't be an issue.
You will need to change the serpentine belt drive pulley to a dual sheave v-belt pulley. You'll not be able to use the one from your current alternator as it has a 17mm shaft and FD alternator has a 19mm shaft. It's possible the length belts used on my alternator may not be correct for the one you intend to purchase. I can see this alternator has twin rectifiers and probably a larger case to house it all,should still bolt to your engine,but may require longer belts. You will need to modify your exciter and charge light harness to plug into the new alternator(look again at pics of my alternator install) and will need to put a diode in the exciter harness to stop battery draw by regulator in alternator when car is shut off because the wire harness in the FB and FD is different. Looks like alternator is on sale for another 5 hours still,good price.
Regarding the alternator,have installed Powermax alternators on a couple of domestic trucks with some serious light upgrades and didn't have any problems with them. In load testing them they were a little shy of claimed output but worked ok otherwise. Never used one on a rotary,but shouldn't be an issue.
You will need to change the serpentine belt drive pulley to a dual sheave v-belt pulley. You'll not be able to use the one from your current alternator as it has a 17mm shaft and FD alternator has a 19mm shaft. It's possible the length belts used on my alternator may not be correct for the one you intend to purchase. I can see this alternator has twin rectifiers and probably a larger case to house it all,should still bolt to your engine,but may require longer belts. You will need to modify your exciter and charge light harness to plug into the new alternator(look again at pics of my alternator install) and will need to put a diode in the exciter harness to stop battery draw by regulator in alternator when car is shut off because the wire harness in the FB and FD is different. Looks like alternator is on sale for another 5 hours still,good price.
09-01-17, 11:43 PM
#11
I am running one of these, and just picked up a couple spares at the junkyard a few weeks ago. It's a very close fit at the distributor and you might have to re-stab the dist to clear an igniter.
https://www.rx7club.com/2nd-generati...785082/page11/
https://www.rx7club.com/2nd-generati...785082/page11/
09-02-17, 05:38 PM
#13
Full Member
Thread Starter
Thanks for all Ur reply's Guys... I have spoken with one of those eBay guys on the phone & he says, like You said, there is a lot more to fitting an FD than just 'bolting it up'....it actually 'bolts up' but there is a lot of other things.....Like GSL4ME says: the diode & such, belt difference....etc..
the same guy (I think) sells an FB alternator souped up to make 130 amps...& that would be bolt up & plug & play... with a warranty. I am borderline on that being enough power to run all the the crap I'm planning on running...I already added up the three amps & their max draw adds up to something like 95 amps..thats a full blast though...(Yea, i'm sure Ill run it a full blast at least more than once.....LOL...)
well, I guess I'll buy the one that makes 130amps if thats all I can really get out one that fits easily...
Thanks for all Ur help...I'll get the thing on the way & see what happens..
I know when these amps don't get the power they want...it's not good.
I'll let Ya'll know.
the same guy (I think) sells an FB alternator souped up to make 130 amps...& that would be bolt up & plug & play... with a warranty. I am borderline on that being enough power to run all the the crap I'm planning on running...I already added up the three amps & their max draw adds up to something like 95 amps..thats a full blast though...(Yea, i'm sure Ill run it a full blast at least more than once.....LOL...)
well, I guess I'll buy the one that makes 130amps if thats all I can really get out one that fits easily...
Thanks for all Ur help...I'll get the thing on the way & see what happens..
I know when these amps don't get the power they want...it's not good.
I'll let Ya'll know.
09-02-17, 08:05 PM
#14
Full Member
Thread Starter
I read back through this post....& everything GSL4ME says is pretty much exactly what I am learning...LOL as i research this subject... & like I said before, I'm just gonna go with the eBay 130 AMP FB re-man unit...
now ,if any of You guys can give me good enough reason not to go this direction Please let me know....I am just looking to get this 'job' done & continue working on other areas of the car...I just don't want to get into some big alternator modification job at the moment... just need more juice!
Thx.
now ,if any of You guys can give me good enough reason not to go this direction Please let me know....I am just looking to get this 'job' done & continue working on other areas of the car...I just don't want to get into some big alternator modification job at the moment... just need more juice!
Thx.
09-02-17, 09:14 PM
#15
ancient wizard...
Well...ok. Read fine print in ebay posting you're looking at,i haven't,but most go like this: full output will not be reached til 1200-1500 rpm,or something to that effect. Which means alt output below that is @1/2 that,so at idle rpm and low vehicle speed you may not have enough amps available for all your "accessories". I recall your original post and wanting something easy to fill the bill... your last solution would likely give you what you need for all your "goodies" AND handle the load for the rest of the car and "whatever other bs i'll have going in there",is a bolt on(with new belts & pulley). You need to upgrade & fuse your output wire for ANY alt. upgrade. Add in the minor exciter plug wire mods that can be done in minutes,you're done. The 130 amp is also a bolt on but possible not enough juice at times...There are threads here to assist you in what's needed.
Last edited by GSLSEforme; 09-02-17 at 09:17 PM.
10-19-17, 08:21 AM
#16
Full Member
Thread Starter
Thx GSL-4Me....
hello,
Been a while since I messed with the car, stereo/alt & etc.. & the Rx& Club.. . ,,,..dealing with a water leak been holding up my stereo job.. ( i been ignoring the car & traveling to hospital a lot & all kind of other crap..LOL....
I hope I didn't come off as a dick..in last post.I take a bunch of medicine & sometimes my words just don't come out right....
sorry.. well, I guess I am going to order the 200 amp'er) FD model & do my best to follow Ur directions ( there is a thread on it right?) & get it hooked up correct.... seal leak, (seems near front window or firewall , driver side.) stereo wiring all done, 10 speakers installed....just the box of (4 more, lol), amps cause it seems to leak in the back too..(driver smuggler hatch) & thats where my amps will go, 2150 watts..lol...
Oh, cleaned my A/C / heater squirt cage fan all cleaned up....made huge difference
!
Been a while since I messed with the car, stereo/alt & etc.. & the Rx& Club.. . ,,,..dealing with a water leak been holding up my stereo job.. ( i been ignoring the car & traveling to hospital a lot & all kind of other crap..LOL....
I hope I didn't come off as a dick..in last post.I take a bunch of medicine & sometimes my words just don't come out right....
sorry.. well, I guess I am going to order the 200 amp'er) FD model & do my best to follow Ur directions ( there is a thread on it right?) & get it hooked up correct.... seal leak, (seems near front window or firewall , driver side.) stereo wiring all done, 10 speakers installed....just the box of (4 more, lol), amps cause it seems to leak in the back too..(driver smuggler hatch) & thats where my amps will go, 2150 watts..lol...Oh, cleaned my A/C / heater squirt cage fan all cleaned up....made huge difference
!
10-19-17, 01:31 PM
#17
ancient wizard...
I didn't put a thread up on it,it was part of a fair amount of restomods i did to my car a while back. Post any questions you need answers to here or maybe start a new thread on this,could probably help others with same issues down the road. I can get you some wiring diagrams,conversion not really difficult. Read back thru my responses in your thread,pretty much outlines what you'll need to do. You can pm me for specifics if you like.
11-02-17, 12:24 PM
#19
Keep in mind; 1hp=746 watts at 100% efficiency. On a 12VDC system that's just over 62 amps per HP, & most devices are far less than 100% efficient (including alternators; average 55% efficient or less in converting mechanical to electric power).
1hp doesn't sound like a lot, but you're only starting with 100-150, losing 3 or 4 may be something to consider.
People pay a lot to get an extra 5hp out of their engine.
1hp doesn't sound like a lot, but you're only starting with 100-150, losing 3 or 4 may be something to consider.
People pay a lot to get an extra 5hp out of their engine.
Seriously though, I did an 80a alternator in an FB and it was more than enough to run a TII engine and all its electronics as well as an aftermarket stereo with an amplifier in it.
12-01-17, 05:08 PM
#20
Full Member
Thread Starter
Hi Fellas...
Hoping to get a little hand holding as I bolt this thing up...LOL...I have bought & received the 200 amp deal..off eBay. looks all nice & brand new.... it has the serpentine belt pulley that is much smaller than the current one. MFG says the included pulley is 'overdrive' by 30% & worth $30....? (says don't throw it away) ... IDK. So, first off, where can I source a two belt pulley for this new alternator? the diameter seems small as to achieve the 'overdrive' condition...so, if I can't find one this diameter, the larger I go the more powerI lose. This pulley (on the new alt) measures about 44mm measured from the top of the grooves. The one on the car is much larger...I also need a different diameter hole for the alternator drive shaft, yes?
Also, GSLSEforme says to start a new thread on this....so it can be easily accessed for future members that wish to make this conversion ??? SO, please let me know if y'all want to go that direction....before You give explanation on this thread....I'll start a new one with an obvious title..
Thanks so much!!!
Sam
Hoping to get a little hand holding as I bolt this thing up...LOL...I have bought & received the 200 amp deal..off eBay. looks all nice & brand new.... it has the serpentine belt pulley that is much smaller than the current one. MFG says the included pulley is 'overdrive' by 30% & worth $30....? (says don't throw it away) ... IDK. So, first off, where can I source a two belt pulley for this new alternator? the diameter seems small as to achieve the 'overdrive' condition...so, if I can't find one this diameter, the larger I go the more powerI lose. This pulley (on the new alt) measures about 44mm measured from the top of the grooves. The one on the car is much larger...I also need a different diameter hole for the alternator drive shaft, yes?
Also, GSLSEforme says to start a new thread on this....so it can be easily accessed for future members that wish to make this conversion ??? SO, please let me know if y'all want to go that direction....before You give explanation on this thread....I'll start a new one with an obvious title..
Thanks so much!!!
Sam