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beechstreet
03-29-2010, 10:28 AM
Anyone remember what on the OEM tensioner needs to be modified to be used with the JRSC? There was a good thread going on about this but its gone thanks to the 2nd crash. I've been searching clubrsx all morning but all the threads are for a k20a2 setup or some other hybrid motor setup.

From what I can remember, you have to cut a tab off so the tensioner can move further, but which one (see pics attached)? Also something about the tensioner possibly hitting the snout of the charger? I have a couple free days to finally attempt modding the OEM tensioner and installing it. Any help would be greatly appreciated.

thanks in advance.

jimmyjames
03-29-2010, 01:52 PM
I believe you need to remove the front-most mounting hole/tab on the tensioner as well as remove 1/4 of the back material from the tensioner. You would then fabricate a mounting plate from 1/4" aluminum stock that screws into the stock mounting holes on the engine (screws need to be flush with plate surface) and also has holes for the tensioner to bolt to it. Overall, the tensioner needs to be 1" or so forward of its current position.
MugenReplica has a modified unit he may be nice enough to photograph. One thing to note though is that the setup was designed for an RSX supercharger orientation. Not sure it works with the EP one.

Actually, I think I know what you mean...without the plate. I'll keep looking.

Twisted-X
03-29-2010, 02:33 PM
Found a couple of threads where they talk about it, but haven't read the whole threads yet:

http://forums.clubrsx.com/showthread.php?t=555282

http://www.k20a.org/forum/showthread.php?t=69749&highlight=jrsc+tensioner

http://forums.clubrsx.com/attachment.php?attachmentid=291087&stc=1&d=1196265691

beechstreet
03-29-2010, 02:43 PM
I believe you need to remove the front-most mounting hole/tab on the tensioner as well as remove 1/4 of the back material from the tensioner. You would then fabricate a mounting plate from 1/4" aluminum stock that screws into the stock mounting holes on the engine (screws need to be flush with plate surface) and also has holes for the tensioner to bolt to it. Overall, the tensioner needs to be 1" or so forward of its current position.
MugenReplica has a modified unit he may be nice enough to photograph. One thing to note though is that the setup was designed for an RSX supercharger orientation. Not sure it works with the EP one.

Actually, I think I know what you mean...without the plate. I'll keep looking.

Yeah didnt need a plate or that much modding. Just had to shave/cut off a restrictor tab. Just not sure if its the part circled in green, or red, or blue in the pic I'm going to attach

beechstreet
03-29-2010, 02:44 PM
Found a couple of threads where they talk about it, but haven't read the whole threads yet:

http://forums.clubrsx.com/showthread.php?t=555282

http://www.k20a.org/forum/showthread.php?t=69749&highlight=jrsc+tensioner

i read through that clubrsx one you posted but couldnt find the exact same thing I was thinking about. thanks though

Twisted-X
03-29-2010, 03:31 PM
Comparing the two photos, I would guess you'd have to remove a little bit of the red box as this would allow the tensioner to swing farther. I'm curious about this myself, as somebody before the crash was saying that this works. (And I might be boosted in the next year or so ;-)

beechstreet
03-29-2010, 03:37 PM
Comparing the two photos, I would guess you'd have to remove a little bit of the red box as this would allow the tensioner to swing farther. I'm curious about this myself, as somebody before the crash was saying that this works. (And I might be boosted in the next year or so ;-)

I think you're right. If I remember correctly someone said that the hardest part was moving the tensioner arm out of the way to cut away the tab circled in red. I wonder if I need to completely remove that little tab or just shave off a little bit of it... guess I should figure out how to move the arm out of the way first. thanks!

Twisted-X
03-30-2010, 01:44 PM
In one of the threads I was reading on K20a one guy said he put the tensioner in a vise while his dad held it open with a breaker bar. Sound kinda iffy to me...
There was another thread where a guy replaced his stock tensioner pulley with one that was 100mmx30mm (this was an rsx with the EPS mod). The only problem with this I could see is that the larger pulley would reduce the amount of leverage the tensioner spring could apply because the belt is farther away from the pivot point. He was also messing with different belt sizes.

MugenReplica
03-30-2010, 02:02 PM
I believe you need to remove the front-most mounting hole/tab on the tensioner as well as remove 1/4 of the back material from the tensioner. You would then fabricate a mounting plate from 1/4" aluminum stock that screws into the stock mounting holes on the engine (screws need to be flush with plate surface) and also has holes for the tensioner to bolt to it. Overall, the tensioner needs to be 1" or so forward of its current position.
MugenReplica has a modified unit he may be nice enough to photograph. One thing to note though is that the setup was designed for an RSX supercharger orientation. Not sure it works with the EP one.

Actually, I think I know what you mean...without the plate. I'll keep looking.

Yea, I use a plate because I have the DC5 JRSC. There are at LEAST 3-4 other EP3s on here who have done the modification of the OEM tensioner using the EP3 JRSC, that you are mentioning here. I don't understand why none of them have piped in to help you. I was going to make a few of these plates last year, but after looking at the Ep3 manifold and it's position, I didn't think it would work, so I didn't bother doing them.


Found a couple of threads where they talk about it, but haven't read the whole threads yet:

http://forums.clubrsx.com/showthread.php?t=555282

http://www.k20a.org/forum/showthread.php?t=69749&highlight=jrsc+tensioner

http://forums.clubrsx.com/attachment.php?attachmentid=291087&stc=1&d=1196265691


That's what I am basically running on my DC5 JRSC with EPS. I don't think it will work with the EP3 JRSC since it moves the tensioner so far forward?


I think you're right. If I remember correctly someone said that the hardest part was moving the tensioner arm out of the way to cut away the tab circled in red. I wonder if I need to completely remove that little tab or just shave off a little bit of it... guess I should figure out how to move the arm out of the way first. thanks!

Just cut the tab that you mentioned. I have a spare OEM tensioner that I will donate to you if this doesn't work. It would just be nice for a fellow Ephatcher to finally share the information with everybody else instead of keeping the information to themselves.

vbpracer
03-30-2010, 10:57 PM
I am actually installing the EP3 JRSC on the k24a2 this saturday. I had issues with the manuel tensioner before I did the engine swap, therefore I will give this a try and write it up.

beechstreet
03-31-2010, 10:26 AM
Just cut the tab that you mentioned. I have a spare OEM tensioner that I will donate to you if this doesn't work. It would just be nice for a fellow Ephatcher to finally share the information with everybody else instead of keeping the information to themselves.

so the entire tab has to be removed? We removed about 3/8 of an inch. We we're a little paranoid about removing the entire thing.

Anyone know what belt I should try with this setup? I have a 62.2" (the one currently on there for the 3.8" SC pulley and 2.5" idler pulley), 61.5", 61.2", as well as the OEM length belt to experiment with. Is it supposed to be a longer belt or shorter?

Thanks in advance

lldiesel386ll
03-31-2010, 10:29 AM
not to sure about the approach to belt sizing, but this may help widen the margin of error :shrug:
http://k20a.org/forum/showthread.php?t=74159
hope that would help someone

Canuck Civic
03-31-2010, 05:03 PM
So I need to fab a plate up to mount the OEM tensioner to work with a DC5 S/C or does someone still make one?

Ba82Ep3
03-31-2010, 08:16 PM
This info WAS posted along with pix previously, and apparently lost with the crash.

To make the OEM auto tensioner work with an EP spec JRSC 3.8 pulley (and smaller) in either a k20 or k24 setup, all you need to mod is the tab that would hit the neck of the JRSC once mounted. Other than that, it bolts in place just fine... no need for a plate. If you cant find a 7 rib belt that fits, look through the 8+ rib offerings, and just cut off the ribs you dont need to have a belt of proper length.

Depending on your setup, you may need to change the auto tensioner pulley size to get proper tension with the belt length used.

http://i206.photobucket.com/albums/bb198/dnewms/JRSCTENSMOD.jpg

Twisted-X
04-01-2010, 02:04 PM
Very good info. Stickified maybe?

skoolnu
04-01-2010, 04:18 PM
I am actually installing the EP3 JRSC on the k24a2 this saturday. I had issues with the manuel tensioner before I did the engine swap, therefore I will give this a try and write it up.

let us know how it works out for you... i was going to sway a k24a2 this year, but i couldnt find a deal. but i will be this winter.

beechstreet
04-01-2010, 09:47 PM
This info WAS posted along with pix previously, and apparently lost with the crash.

To make the OEM auto tensioner work with an EP spec JRSC 3.8 pulley (and smaller) in either a k20 or k24 setup, all you need to mod is the tab that would hit the neck of the JRSC once mounted. Other than that, it bolts in place just fine... no need for a plate. If you cant find a 7 rib belt that fits, look through the 8+ rib offerings, and just cut off the ribs you dont need to have a belt of proper length.

Depending on your setup, you may need to change the auto tensioner pulley size to get proper tension with the belt length used.


Thanks for the info. Do you happen to remember if the tab has to be completely removed? Also, any idea what length belt to start with? On clubrsx I was reading anywhere from a 50" and up

Ba82Ep3
04-02-2010, 07:42 AM
I used the manual tensioner (unfortunately) on my k24/JRSC setup. The pic is of an EP owned by a friend of mine. He has a complete k20a JDM swap with the 3.8 on the JRSC. He is also using a k24a1 CP, since the k20a CP is so much smaller. I think hes running a 62.5" Gatorback, and the auto tensioner is right where it needs to be.

Were getting up tomorrow to work on his tune (good weather finally), so i will get some more pix... but from what i have seen, he didnt remove the WHOLE tab. You can even see some of it is still there in the pic on the previous page.

K20A EP3
04-02-2010, 04:01 PM
:mcool:

PAPITUYO326
04-02-2010, 05:21 PM
Great info here!

Should be able to backtrack a belt length from this!

04EP3Hatch
04-03-2010, 04:10 AM
This info WAS posted along with pix previously, and apparently lost with the crash.

To make the OEM auto tensioner work with an EP spec JRSC 3.8 pulley (and smaller) in either a k20 or k24 setup, all you need to mod is the tab that would hit the neck of the JRSC once mounted. Other than that, it bolts in place just fine... no need for a plate. If you cant find a 7 rib belt that fits, look through the 8+ rib offerings, and just cut off the ribs you dont need to have a belt of proper length.

Depending on your setup, you may need to change the auto tensioner pulley size to get proper tension with the belt length used.

http://i206.photobucket.com/albums/bb198/dnewms/JRSCTENSMOD.jpg

waittt, so all you do is file down an ear? does it mount still up to the three holes? or do you rotate it?

K20A EP3
04-03-2010, 05:06 AM
Just cut the mounting hole off that would be hitting the SC neck

04EP3Hatch
04-03-2010, 07:13 AM
Just cut the mounting hole off that would be hitting the SC neck

well the bolt at the very top of that picture looks like theres nothing behind it to thread into, thats why it looks like it rotated on the mount

K20A EP3
04-03-2010, 12:34 PM
im pretty sure it just goes thru and threads into the ideler pulley. its not the that bad just hold the charger up 2 it with the tension on and ull see what i mean

Ba82Ep3
04-03-2010, 06:15 PM
Yep, yep. No rotation of the tensioner. Just bolt it on and youre done. If i remember correctly, the third hole mounts the idler pulley... but it has been a LONG time since i have had that on there, so i would have to check that to be certain.

In that pic he has about 3mm of clearance between the tab and the SC neck... i looked at it again today... and another pic wouldnt really clarify anything more than what you already see.

In case you guys wondered, K20A EP3's (Chris') KDL showed his JRSC setup builds 8.5psi at 8,500rpm. IAT temps were just around 100* with ambient air temp around 75*.

K20A EP3
04-04-2010, 06:56 AM
woot woot! im thinking i might just put the cluch and tranny in and leave my sc setup alone for a lil while. desperatly feel like ima need the water meth for those 100+ days this summer. got some videos on my girls droid yest. just need 2 post em up.

Twisted-X
05-01-2010, 11:14 PM
Found this vid someone made that modified their stock tensioner to work with the JRSC:


http://www.youtube.com/watch?v=MN4WIQ_HB-A

Demonicrsx
05-24-2010, 12:00 AM
subscribed, been looking for a solution to getting rid of the JR manual tensioner and use our stock one. My scenario is a little bit different since I have done a kswap in my ek with the rsx jr sc kit. I am testing out the jose modified bracket which allow the use of the stock tensioner system and the PS. I will post up what I have found out but as for cutting the tab off the tensioner, I am a little iffy lol. So we are cutting off the whole tab that is in the red box on the picture? I think that JR release a new type of tensioner, its a stock one but they modified it which cost 400 bucks, don't know what they did but I don't think its worth it.

beechstreet
06-06-2010, 06:05 PM
I took a shot at installing the OEM auto tensioner today. I had already shaved the restricting tab and had a large selection of belts to try.

Here are the shots of the restricting tab I shaved. The green box is where I did the shaving so it moves further. The 2nd picture shows how much further the arm moves now with the tab shaved down (those two green marks used to line up).

http://i150.photobucket.com/albums/s86/teambeechstreet2/Supercharger/DSCF0653_2.jpg
http://i150.photobucket.com/albums/s86/teambeechstreet2/Supercharger/DSCF0654_2.jpg

First problem I encountered was that the OEM tensioner prevented the supercharger from mounting up correctly. The neck of the JRSC was coming into contact with the tensioner so two cutting wheels later I had removed a large piece of the tensioner as seen in the pics below:

BEFORE
http://i150.photobucket.com/albums/s86/teambeechstreet2/Supercharger/DSCF0582.jpg

AFTER
http://i150.photobucket.com/albums/s86/teambeechstreet2/Supercharger/DSCF0655.jpg

How were some of you able to mount up the OEM tensioner and JRSC without cutting off that huge piece?

Now that everything lined up the next problem I had was that the JRSC pulley rubbed against the 3" OEM tensioner pulley. So now I need to see if any other k-motors have an OEM tensioner pulley that is smaller. Is the K20A2 OEM tensioner pulley a 2.5"? I know the one that Moss Motors sells for the A2 manual tensioner is a 2.5" but I'm looking for the OEM one. If I can't find one then I'm just gonna order another manual tensioner from Moss Motors.

Hope these pictures help somebody.

02CivicSI-VTEC
06-07-2010, 11:14 AM
hey Chris, if this work out let me know so i can do it for my supercharged setup aswell.

beechstreet
06-08-2010, 07:16 AM
so far the only pulley I've found that I can use to replace the 3" tensioner pulley is a dayco one that is 2.75" but I don't think it is enough clearance. Looks like I'm just gonna order another manual tensioner if Moss still has'em

Anubisx_13
06-08-2010, 08:17 AM
I took a shot at installing the OEM auto tensioner today. I had already shaved the restricting tab and had a large selection of belts to try.

Here are the shots of the restricting tab I shaved. The green box is where I did the shaving so it moves further. The 2nd picture shows how much further the arm moves now with the tab shaved down (those two green marks used to line up).
http://i150.photobucket.com/albums/s86/teambeechstreet2/Supercharger/DSCF0653_2.jpg
http://i150.photobucket.com/albums/s86/teambeechstreet2/Supercharger/DSCF0654_2.jpg

First problem I encountered was that the OEM tensioner prevented the supercharger from mounting up correctly. The neck of the JRSC was coming into contact with the tensioner so two cutting wheels later I had removed a large piece of the tensioner as seen in the pics below:

BEFORE
http://i150.photobucket.com/albums/s86/teambeechstreet2/Supercharger/DSCF0582.jpg

AFTER
http://i150.photobucket.com/albums/s86/teambeechstreet2/Supercharger/DSCF0655.jpg

How were some of you able to mount up the OEM tensioner and JRSC without cutting off that huge piece?

Now that everything lined up the next problem I had was that the JRSC pulley rubbed against the 3" OEM tensioner pulley. So now I need to see if any other k-motors have an OEM tensioner pulley that is smaller. Is the K20A2 OEM tensioner pulley a 2.5"? I know the one that Moss Motors sells for the A2 manual tensioner is a 2.5" but I'm looking for the OEM one. If I can't find one then I'm just gonna order another manual tensioner from Moss Motors.

Hope these pictures help somebody.

what sc pulley are you running i heard some where you cant run the 4.0 because it will rub? im not sure though i could have mis read

beechstreet
06-08-2010, 08:32 AM
what sc pulley are you running i heard some where you cant run the 4.0 because it will rub? im not sure though i could have mis read

I'm running the 3.8" SC pulley.

Twisted-X
06-08-2010, 03:44 PM
Now that everything lined up the next problem I had was that the JRSC pulley rubbed against the 3" OEM tensioner pulley. So now I need to see if any other k-motors have an OEM tensioner pulley that is smaller. Is the K20A2 OEM tensioner pulley a 2.5"? I know the one that Moss Motors sells for the A2 manual tensioner is a 2.5" but I'm looking for the OEM one. If I can't find one then I'm just gonna order another manual tensioner from Moss Motors.


I wonder if the next size smaller belt would help with this?

I wish somebody would engineer a gear and chain or a ribbed belt type setup for this thing and just have it run right off a modified crank pulley.

beechstreet
06-08-2010, 09:26 PM
I wonder if the next size smaller belt would help with this?

My personal problem is that the pulleys hit eachother without a belt being installed at all. If the tensioner pulley was a good half inch smaller in diameter, it might just work.

K20A EP3
06-12-2010, 08:50 AM
i didnt notch the green are like you did in ur pics. all i did was cut the mounting hole off for the ideler pulley. What size SC pulley are you using? Im on the 3.8 and and the tensioner pulley sits pretty close 2 it but its swing isnt long enough 2 hit it. Ive been running like this for a few months now on a 6 rib dayco with no belt slip


*edit* just seen above you have the 3.8 lol

Anrasmor
08-26-2010, 07:05 AM
My personal problem is that the pulleys hit eachother without a belt being installed at all. If the tensioner pulley was a good half inch smaller in diameter, it might just work.

Did you ever get the auto tensioner to sit properly?

Ba82Ep3
08-26-2010, 07:55 AM
Did this ever get resolved? Does anyone know if the k20a alternator pulley is a different size than the k20a2/3 alternator pulley (dont have Chris' car handy to check)? Thats the only variable i can think that could exist.

The WP pulley is the same size, so is the AC pulley... if you are using the k20a3/k24a1 CP with a 3.8 and the alternator pulley is identical in size, then there should be clearance for the auto tensioner.

:confused:

beechstreet
08-26-2010, 06:18 PM
Did you ever get the auto tensioner to sit properly?

No, just haven't had the time to take another shot at it. I think the mistake I made was removing the restrictor tab (circled in green in first pics). I'm going to try and get my hands on another OEM auto tensioner and make a 2nd attempt when I have some free time.

Anrasmor
08-26-2010, 06:46 PM
No, just haven't had the time to take another shot at it. I think the mistake I made was removing the restrictor tab (circled in green in first pics). I'm going to try and get my hands on another OEM auto tensioner and make a 2nd attempt when I have some free time.

I think Mugenreplica said he had an extra for ya. :P

neoamd
09-28-2010, 05:20 PM
Need more responses here. If anyone has a OEM auto tensioner they would like to sell LMK and I will buy it now. My belt slip issues are PISSING me off.

beechstreet
02-27-2011, 09:25 AM
Hey all, made a quick "How To" for modding the OEM tensioner. Please let me know if I left anything out so I can edit it. THanks!
http://www.ephatch.com/forum//showthread.php?62179-How-To-Modify-OEM-Auto-Tensioner-for-JRSC

K20A EP3
02-28-2011, 04:02 PM
Props^^^^^^