Acura RSX, ILX and Honda EP3 Forum banner

1 - 20 of 22 Posts

·
Scotty we need more POWER
Joined
·
280 Posts
Discussion Starter #1
In my plight for more ponies I decided to go to a 72mm TB which I intend to match to a new TB-SC Manifold, I was lured by the cost of the OBX unit, even though I am well aware of 'You get what you pay for' - I can almost hear people saying "Oh no you didnt" - well someone had to........

So when it arrived I promptly got it out to measure it after being duped by a previous and even more inferior TB that I had previously ordered receiving a 70mm not a 72mm. So I measured the air filter end of the TB throat and that was 73.75mm - initially prompting me to think they had sent the wrong part but before opening my big mouth I measured the outlet and that measures 71.70mm so its fair to say they had sent me the right part. After noticing the big 72 laser etched into the side I was pretty convinced I had the right part.

First appearances aren’t great, some of the machining leaves a lot to be desired, never the less it does look like a hoofing great throttle body.

First turn of the shaft via the cable fixing confirmed everything I had read on the web about them being sticky and this was without any heat of the engine bay to make everything expand. The spring didnt have the oomph that the OEM unit has so that might need some attention.

So I was intrigued as to what was causing the shaft to labour like it was - out came the tools.......

On turning the first bolt it became apparent that there wasn’t a lot of Loctite or fixant in use, even on the butterfly valve bolts. I got the TPS fixing off to notice a cheap rubber oil seal. Under the cable fixing was another oil seal, below the two outer fixings are two Chinese (ZXZC) made 608RS bearings, with rubber seals, they feel average – a bit sloppy.

So once this lot was apart it was really evident that the oil seals are what are causing the sticking with the TB at room temperature. I obviously have yet to see if sticks with added heat.

With all of that in mind I ordered new bearings 608RS-2 C3 SKF and 2x Viton Seals (8x22x7) and await to see how it feels once they arrive....... I will keep you posted.

It is very true - you do get what you pay for and this can be made a whole lot better by spending an hour and about $25 on new bearings and seals - I might even fore-go the seals if the Vitons are any where near as sticky as the rubbers, again got to wait and see, I doubt it knowing other Viton seals but still......

I took a load of photos so people can see what I am going on about, starting with OEM and OBX comparison then leading onto the strip down:
































 

·
Alky fed rat.
Joined
·
1,637 Posts
In my plight for more ponies I decided to go to a 72mm TB which I intend to match to a new TB-SC Manifold, I was lured by the cost of the OBX unit, even though I am well aware of 'You get what you pay for' - I can almost hear people saying "Oh no you didnt" - well someone had to........

So when it arrived I promptly got it out to measure it after being duped by a previous and even more inferior TB that I had previously ordered receiving a 70mm not a 72mm. So I measured the air filter end of the TB throat and that was 73.75mm - initially prompting me to think they had sent the wrong part but before opening my big mouth I measured the outlet and that measures 71.70mm so its fair to say they had sent me the right part. After noticing the big 72 laser etched into the side I was pretty convinced I had the right part.

First appearances aren’t great, some of the machining leaves a lot to be desired, never the less it does look like a hoofing great throttle body.

First turn of the shaft via the cable fixing confirmed everything I had read on the web about them being sticky and this was without any heat of the engine bay to make everything expand. The spring didnt have the oomph that the OEM unit has so that might need some attention.

So I was intrigued as to what was causing the shaft to labour like it was - out came the tools.......

On turning the first bolt it became apparent that there wasn’t a lot of Loctite or fixant in use, even on the butterfly valve bolts. I got the TPS fixing off to notice a cheap rubber oil seal. Under the cable fixing was another oil seal, below the two outer fixings are two Chinese (ZXZC) made 608RS bearings, with rubber seals, they feel average – a bit sloppy.

So once this lot was apart it was really evident that the oil seals are what are causing the sticking with the TB at room temperature. I obviously have yet to see if sticks with added heat.

With all of that in mind I ordered new bearings 608RS-2 C3 SKF and 2x Viton Seals (8x22x7) and await to see how it feels once they arrive....... I will keep you posted.

It is very true - you do get what you pay for and this can be made a whole lot better by spending an hour and about $25 on new bearings and seals - I might even fore-go the seals if the Vitons are any where near as sticky as the rubbers, again got to wait and see, I doubt it knowing other Viton seals but still......

I took a load of photos so people can see what I am going on about, starting with OEM and OBX comparison then leading onto the strip down:
































Nice write up, I did one awhile back when I first tried mine,http://forums.clubrsx.com/showthread.php?t=685561.

I did find that there was some binding, in my case the tps when tight rubbed on the bearing underneath it. I made a new slightly thicker gasket for the TPS and that took care of it. I also noticed it wanted to stick when opening the throttle initially, it seemed like the butterfly had very sharp edges and was catching on the throttle body, a little steel wool did the trick. It actually is better when its all warmed up.

Subscribed to see how the rebuild goes, keep up the good work.

Scott
 

·
Scotty we need more POWER
Joined
·
280 Posts
Discussion Starter #3
Cheers Scott - will do..

After spending today drawing it up I am considerably more familiar with it, bearings and seals should be here early in the week.

Once I get the bearings and seals I will make a decision on the use of the seals or get some spacers made up to go in there place, I dont see any reason for an oil seal on the TPS side as there is a gasket under the TPS keeping the crud out so maybe one seal used on the cable fixing side??!!?

The taper of the inlet goes from 74 to 72 (+/-.2mm) in a depth of 43mm then straightens out til the outlet into the TB-SC manifold.

The TPS side of the TB has thrown up a problem with my current design for the TB-SC manifold so that'll need a re-think before I get it machined which was due next week - it is alot wider than the OEM TB.......

OK so here's how its looking (minus the oil seals and fixings):





















 

·
Been there & gone back
Joined
·
2,315 Posts
Cheers Scott - will do..

After spending today drawing it up I am considerably more familiar with it, bearings and seals should be here early in the week.

Once I get the bearings and seals I will make a decision on the use of the seals or get some spacers made up to go in there place, I dont see any reason for an oil seal on the TPS side as there is a gasket under the TPS keeping the crud out so maybe one seal used on the cable fixing side??!!?

The taper of the inlet goes from 74 to 72 (+/-.2mm) in a depth of 43mm then straightens out til the outlet into the TB-SC manifold.

The TPS side of the TB has thrown up a problem with my current design for the TB-SC manifold so that'll need a re-think before I get it machined which was due next week - it is alot wider than the OEM TB.......

OK so here's how its looking (minus the oil seals and fixings):





















The seals are to prevent moisture as well as crud I would think with spacers moisture would still make its way in and foul up the TPS. I know thats the biggest killer of the TPS these days.
 

·
Scotty we need more POWER
Joined
·
280 Posts
Discussion Starter #6
I've been thinking about the moisture thing and for my build its probably not as much of an issue as the engine is mid mounted in the car, with a diffuser underneath and considerable inner arches, plus it only see's dry roads as its a bit much in the wet - been there, tried that, it wasnt that much fun apart from when I got in a large empty car park and hung the back end out for a few laps of it, it felt just like an old racing kart I used to own....
 

·
Scotty we need more POWER
Joined
·
280 Posts
Discussion Starter #8
Machining the TB-SC Manifold has been the main use of spare hours.

When I got the Viton seals through I did try them but they felt almost equally as restrictive.

I am going down the route of having some spacers made to replace the seals as moisture in the engine bay is not an issue for me. Once I get them made and start putting it back together I will do a write up.
 

·
Registered
Joined
·
841 Posts
at the end what happened?

I'm going to try one of those cheap ebay chinese TB's for $70 as you said somebody has to do it...

 

·
Super Moderator
Joined
·
23,752 Posts
yeah saw someone else having idle issues with a knockoff because of to much air. The butterfly wasn't closing all the way.
 

·
Registered
Joined
·
841 Posts
I bought one just like the one picture above for 80 bucks on ebay. After cleaning up the rough edges on the butterfly and doing some adjusting it's working just as good as my OEM TB was. I love it.
what kind of adjustments did you do? Please give me more info. Didn't get stuck? how is the pedal feeling? also what throttle bracket did you use? I want to keep my stock throttle cable because i like how long is to tuck it on the fender.

Mine is coming soon
 

·
Registered
Joined
·
841 Posts
Update:
Finally I got the Chinese 70mm TB for $78 from ebay. it's the exact copy of the S90. I just installed it last Saturday i had to unscrew the studs from the PRC also I had to hacksaw the headless screws to swap the tps. I had to use the same bracket for the cable and swapped all the rest of sensors and the IACV (after cleaning it, of course) and is working fine, I feel more torque now and the car revs faster.

The pedal feels stiffer than stock for sure but I am getting used to it
the idle is almost like stock
in a cold start it revs at 2000 at first and slowly starts to go down
during normal operation the idle remains between 700-550 sometimes it bouces a little but not too much.
It didn't get stuck yet I hope it wont
before install I saw the TB against the light and was almost perfect seal.

So I recommend it.

 

·
Registered
Joined
·
841 Posts
another update:

i recalibrated the TPS and the idle is just perfect!!! (i just moved the TPS all over clockwise and the annoying P0122 dissapeared) now it idles at 700RPM purrs like a kitten!!!

The pedal now is softer just like stock!!!

i'm totally happy
 

·
Registered
Joined
·
841 Posts
mine has been working perfect so far no issues at all
 

·
Scotty we need more POWER
Joined
·
280 Posts
Discussion Starter #19
I tried again to get the OBX TB working but I gotta be honest its beyond fixing without making a brand new throttle plate, it got 5thou gaps at either side of the throttle plate where the spindle is, this lets through way too much air. I have been lapping the plate in with really fine lapping paste but that still doesnt work due the side gaps.

So feck it, I bought myself a new 70mm TB, made by Clockwise Motion, yes, the same people that make the baffled sump insert. British made using OEM seals and bearings.

Here it is against the OEM TB:




Thats gonna get me back the missing power since ditching the old 72 just
after having it dyno'd last.....


.
 

·
Hawks
Joined
·
5,634 Posts
not too thread jack but I might be purchasing a 76mm s90 throttle body to see how it works out. also might have to upgrade my intake to a 3.5 inch intake since my current intake od is 3 inch and want to run a true 3 inch intake so I might have to buy 3.5 inch intake tubes. will an over sized intake matter if my throttle body is only 76mm roughly 3 inches?
 
1 - 20 of 22 Posts
Top