Jump to content
The mkiv Supra Owners Club

Fitting UK clocks in a j spec car


LOGIE

Recommended Posts

Well that is a very comprehensive answer. Thanks for that mate. If I put Uk clocks in and remove the delimiter/converter will I be restricted to 112mph? Also will my odo go up in miles?

I'm at the edge of my knowledge here, but if you put UK clocks in and removed the converter/delimiter, you'd still be limited to 112mph. This is because (I'm not 100% sure of this) the speedo is the only component that decodes the pulses into a number. The rest of the components (odo, ECU, etc) still use the "4 pulses per wheel rev" signal. The JSpec ECU prevents further acceleration when it receives an input pulse frequency equivalent to 112mph: without reducing or capping the pulse frequency, you'll be limited to 112mph. To disable the speed limit, you have to cap the pulse frequency (this is what the good limiters do), or as a nasty fudge scale it back by a big enough factor so the engine runs out of puff before you reach an "alleged" 112mph. E.g. if you reduced the frequency by half, an alleged 112mph would be an actual 224mph, and a 2JZ without serious modifications wouldn't reach that.

 

I think your odo (if it's a JSpec one) would count up in kilometres. The JSpec odo counts the pulses, and displays the number as the number of kilometres travelled. A UK odo counts the pulses and displays the number as the number of miles travelled.

Edited by stevie_b (see edit history)
Link to comment
Share on other sites

I'm at the edge of my knowledge here, but if you put UK clocks in and removed the converter/delimiter, you'd still be limited to 112mph. This is because (I'm not 100% sure of this) the speedo is the only component that decodes the pulses into a number. The rest of the components (odo, ECU, etc) still use the "4 pulses per wheel rev" signal. The JSpec ECU prevents further acceleration when it receives an input pulse frequency equivalent to 112mph: without reducing or capping the pulse frequency, you'll be limited to 112mph. To disable the speed limit, you have to cap the pulse frequency (this is what the good limiters do), or as a nasty fudge scale it back by a big enough factor so the engine runs out of puff before you reach an "alleged" 112mph. E.g. if you reduced the frequency by half, an alleged 112mph would be an actual 224mph, and a 2JZ without serious modifications wouldn't reach that.

 

I think your odo (if it's a JSpec one) would count up in kilometres.

Thanks Stevie I appreciate it. Nicely worded for non electrical types like myself, NA-TT seemed easy until the final few things came to light and they are all electrical issues.

Link to comment
Share on other sites

For info, that is the same converter/de-limiter I used when installing the UK clocks. Is there any reason you can't just swap the dial face and retain the jspec cluster?

 

If you want to wait a bit I'll be selling my jspec/UK hybrid cluster once my other car is up and running (Facelift so I don't need the dials anymore)

Link to comment
Share on other sites

For info, that is the same converter/de-limiter I used when installing the UK clocks. Is there any reason you can't just swap the dial face and retain the jspec cluster?

 

If you want to wait a bit I'll be selling my jspec/UK hybrid cluster once my other car is up and running (Facelift so I don't need the dials anymore)

Let me know as soon as your selling your hybrid cluster mate as it could still come in handy if all else fails. I could put the uk speedo face into the j spec TT cluster but the condition of the cluster isn't great (white mounting tab is broken along with some little retaining clips, was sold it this way without being told). ScottC posted me a link showing how to make the NA clocks works in a TT but there are accuracy issues if you read into it.

 

So yeah Homer gimme a shout anyway ref hybrid cluster mate.

Link to comment
Share on other sites

Let me know as soon as your selling your hybrid cluster mate as it could still come in handy if all else fails. I could put the uk speedo face into the j spec TT cluster but the condition of the cluster isn't great (white mounting tab is broken along with some little retaining clips, was sold it this way without being told). ScottC posted me a link showing how to make the NA clocks works in a TT but there are accuracy issues if you read into it.

 

So yeah Homer gimme a shout anyway ref hybrid cluster mate.

 

No problem. I also have a spare TT auto cluster in my parts box but has a couple of busted gauges. The casing and circuit board are fine from what I recall, would that help you at all?

Link to comment
Share on other sites

No problem. I also have a spare TT auto cluster in my parts box but has a couple of busted gauges. The casing and circuit board are fine from what I recall, would that help you at all?

Definitely mate that would help big time, no hurry just gimme a shout when your ready buddy. Very much appreciated.

Link to comment
Share on other sites

Let me know as soon as your selling your hybrid cluster mate as it could still come in handy if all else fails. I could put the uk speedo face into the j spec TT cluster but the condition of the cluster isn't great (white mounting tab is broken along with some little retaining clips, was sold it this way without being told). ScottC posted me a link showing how to make the NA clocks works in a TT but there are accuracy issues if you read into it.

 

So yeah Homer gimme a shout anyway ref hybrid cluster mate.

That was only for the rev counter

Link to comment
Share on other sites

That was only for the rev counter

 

I know mate. I done a little reading and on the us forums there were a few guys who had problems with it. Your help and patience was great mate but the ABS got me beat I tried everything including putting the old NA clocks back in. Im just trying to sort out the speedo and wipers so its at least driveable if I can't sus the ABS out I can at least take it to a garage without worrying about speeding or it raining.

Link to comment
Share on other sites

With reference to wipers not working; have you changed the N/A bulkhead loom for a T.T. auto?

 

If so, 2 or maybe 3? of the wiper wires are pinned differently.

 

Yep David Ive fitted a TT engine bay loom so I could run electric fans amongst other things. I did wonder whether there Would be a difference but didnt notice any. Its definitely wiring thats at fault I checked the motor on a battery today and its fine.

Link to comment
Share on other sites

I meant the bulkhead loom behind the dash, but the engine bay loom is it's t'other half.

 

2 or 3 of the wiper wires, (can't remember without looking) are routed through the connector block on the opposite side of the car.

 

You need to follow the wiper wires from the column loom and compare the T.T. engine bay loom with the N/A.

Edited by David P (see edit history)
Link to comment
Share on other sites

I meant the bulkhead loom behind the dash, but the engine bay loom is it's t'other half.

 

2 or 3 of the wiper wires, (can't remember without looking) are routed through the connector block on the opposite side of the car.

 

You need to follow the wiper wires from the column loom and compare the T.T. engine bay loom with the N/A.

 

Cheers David if you remember which wires are different please let me know.

Link to comment
Share on other sites

Just look.

 

The wiper wires are bare to see at the column loom connector, see if they go left or right then find the corresponding coloured wires in your N/A bay loom, join the dots and Bingo.

 

From what you're saying they must have jiggled with the looms on either the TTs or NAs. I fitted a 94 tt engine bay loom to a 93 na and everything worked.

Edited by ScottC (see edit history)
Link to comment
Share on other sites

Mine began life as a peasant spec N/A auto, built Nov 94, registered Jan 95 and I swapped in a T.T. auto bulkhead-loom (year unknown) that had active-spoiler and cruise-control.

 

All was well except for those 2 or 3 wiper wires that were routed to the opposite connector block.

Link to comment
Share on other sites

Mine began life as a peasant spec N/A auto, built Nov 94, registered Jan 95 and I swapped in a T.T. auto bulkhead-loom (year unknown) that had active-spoiler and cruise-control.

 

All was well except for those 2 or 3 wiper wires that were routed to the opposite connector block.

 

I have a 93RZ dash/bulkhead loom here which I was going to fit for trac/slip control. I think I'll leave it till my other problems are resolved. Looks like I'll be either standing on my head in the drivers footwell or stripping out the wheel arch liner or both this weekend. The joys.

Link to comment
Share on other sites

Mine began life as a peasant spec N/A auto, built Nov 94, registered Jan 95 and I swapped in a T.T. auto bulkhead-loom (year unknown) that had active-spoiler and cruise-control.

 

All was well except for those 2 or 3 wiper wires that were routed to the opposite connector block.

 

so in theory i would have had to do the same when plugging my tt engine bay loom into my na bulkhead loom? :think:

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.