1987 3.2 Carrera Backdate project - Sladeys hotrod

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sladey
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

Thanks Wayne and thanks Peter - that’s what I’ll be checking first
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sladey
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

As an update on this, I started moving the wires around near the immobiliser unit and I could hear it clicking. The clicking seemed to indicate that it was switching on and sure enough, when I tried the plipper it worked!!!

So I racking there was a break or dodgy connection.

There were 2 multi plugs going into the unit. One of them seemed to include power as I got the clicks whenever I plugged that in.

I stripped all the insulation tape and checked everything but there were no breaks.

Looking inside the power plug I could see 3 of the terminals were green. Initially the whole unit would go off and on again several times when the wires were wiggled, but after replugging that power plug several times the unit just stayed on - no errors.

I deduced that the green corrosion was making the connection poor and I’d managed to move it yesterday. My unplugging and replugging cleaned up the relevant parts of the connectors.

To stop it happening again I sprayed in some electrical contact cleaner and then used some of the wife’s interdental sticks (must remember not to kiss her for a while) to clean it out properly.

To cap it all I taped the wires back up, taped around the unit to help stop water ingress and the. Covered it with some foam from an exercise mat - which will stop any knocking but also ensure any water dripping down doesn’t run into the box.

Then I was able to carry on with the wiring changes….
The simple things you see are all complicated
I look pretty young but I'm just backdated yeah
Bruce M
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by Bruce M »

I’d guess the switched power feed is a direct feed from the ignition switch and not indirect where the key power triggers a relay. For those accessories, I’d probably use a relay so the power comes direct from the battery, via a fat wire, fuse & the relay.

The complex electric items will have some form of microcontroller or such like that will have a boot up delay of perhaps a 0.5 second or longer. When you pause after power up, these units are booted up. On crank you may get a very short dip in voltage below the minimum for those components. It will be too short to measure except with an oscilloscope. That could be enough to trip up the microcontroller & get an error code. I had this problem with my dash screen (multi-gauge screen linked to the ECU). I fixed my issue with a set of capacitors, wired together , to stop the voltage dropping below the minimum needed to power the dash computer.
sladey
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

Thanks for that Bruce, will running the green wire to a fused block help with that? - each of the 4 outputs will have their own fuse and they are all low amps

* TracTive Switched Feed: < 0.1 Amps (Signal only)
* Amplifier Remote: < 0.5 Amps (Signal only)
* Audioengine Bluetooth: < 0.5 Amps (Device power)
* Classic Retrofit A/C Button: < 0.5 Amps (Signal only)

AI had also suggested a beefy supply and a relay but that was when it thought it was supplying a lot more - once I clarified the low amps involved it seemed to think it would be OK.
The simple things you see are all complicated
I look pretty young but I'm just backdated yeah
rhd racer
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by rhd racer »

Good news Mark


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71 914/6 3.0 - gone

'You see Paul, hill climbing is like making love to a beautiful woman. You get your motor running, check your fluids, hang on tight and WHOA..30 seconds later it's all over!' Swiss Tony
Bruce M
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by Bruce M »

Your corroded connector could have also added to the problem, as it creates a resistance & therefore a voltage drop.

The issue I experienced was not due to a particularly high current consumption of the accessory. The problem was the starter motor coils having a heavy inrush current which very briefly pulled down the battery voltage, to under 9v for a fraction of a second.

A capacitor acts like a very small capacity battery which charges/ discharges quickly. They are used in power supplies to smooth the “folded” AC signal from a rippling DC, into a smooth DC, by charging & discharging rapidly. I bought a pack of 5 capacitors, rated for 25volts and 10,000 microfarads (uF) each. When wired in parallel, they make 50,000 uF, which is a decent buffer. Those were wired in (between the 12v & earth) close to the accessory, and had enough capacity to “top up” the main battery voltage & stop it dropping below the minimum needed for the microprocessor. In my case the dashboard computer would instantly shut down when I cranked the engine, due to the tiny interruption of it’s power.

As said above, you’ll be able to check via an oscilloscope, if the voltage drops on cranking, as it may be very brief, to confirm if that is a possible cause . The instructions for the suspension, Bluetooth etc, hopefully states what the minimum voltage needs to be too.

Also might nothing to do with that!!
sladey
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1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

OK just wrap up the wiring side of things, the fuse box arrived and I made a bracket to fit it under the front seat
Image

The ran the wire from the ignition into that and the four supplies out of it, and labelled it all up

Image

I’m slowly getting more comfortable with wiring - I’ve actually bought some decent ratcheting crimping pliers now which makes the whole thing a lot more pleasurable - gotta love a good tool

This reorganisation of the wiring has made the intermittent problems with the tractiv disappear. I’ve got to wait until I’m daily driving it now to check that the other problem with Bluetooth vs Aircon is also fixed.


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Last edited by sladey on Sun Jul 12, 2026 7:38 pm, edited 1 time in total.
The simple things you see are all complicated
I look pretty young but I'm just backdated yeah
sladey
Nurse, I think I need some assistance
Posts: 9365
Joined: Sat Apr 23, 2005 9:08 pm
Location: Nottingham, UK

1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

When I put the car in to Center gravity they remarked that the front tyres were shot and one of the rears was far more worn than the other side. I think I mentioned that earlier. I managed to replace the one worn rear before my alps trip and as part of a late night eBay session I ordered two more rear tyres - 225/50x15s Toyo proxes - reasoning I’d get my use out of them when the rears needed replacing again.

I was concerned about the fronts - I’ve had 205/55x15 Toyo proxes on there for years and a couple of years ago I found out that Toyo have stopped making them. This lead to many internet searches on the alternatives. I don’t really want to switch from Toyos as I’ve used them for over 20 years and really like them.

I was considering 195/55s but was concerned they might be a bit narrow. When ordering my rear tyres I noticed that the rim width recommended for the 225/50s was between 7 and 8 inches.

As the fronts needed replacing (after being told they were knackered I ragged them round the alps for a week, as you do), and I had a pair of 225/50s knocking about I thought sod it and took them to the tyre place and asked them to fit them.

There was a bit of sucking of teeth but they carefully fitted them. I was getting a little bit of rubbing from the top of the tyre and some on lock but nowhere near as much as I was expecting.

they looked a bit ‘snug’ innit
Image

I thought the car could stand to be raised slightly front and rear to preserve the rake so that week-end I raise front and rear two threads. this was really easy with the tractivs

I also tweaked one of the lokari arch liners with the dual purpose of adding a bit more space on Gulliford lock and letting the front radiator breathe a bit better
Image

And I’ve ended up with this
Image
Which I think looks pretty good. The handling is not a lot different - certainly feels no heavier at the front and maybe a bit sharper on the turn-in which I like.


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Last edited by sladey on Sun Jul 12, 2026 7:50 pm, edited 1 time in total.
The simple things you see are all complicated
I look pretty young but I'm just backdated yeah
rhd racer
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by rhd racer »

Looks good - glad you got the wiring sorted


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99 Boxster 2.5 > 3.4 hill climber

71 914/6 3.0 - gone

'You see Paul, hill climbing is like making love to a beautiful woman. You get your motor running, check your fluids, hang on tight and WHOA..30 seconds later it's all over!' Swiss Tony
sladey
Nurse, I think I need some assistance
Posts: 9365
Joined: Sat Apr 23, 2005 9:08 pm
Location: Nottingham, UK

1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

Now some time ago, on one of Chris Jury’s excellent updates he mentioned he’d moved his drivers seat inwards to put it more in line with the steering wheel and pedals.

This reminded me that when I fitted my seats the brackets had two holes - I initially tried to use the innermost holes but this lead to fouling on the seat belt bracket so I had to choose the outermost. They two holes were only perhaps 5mm apart anyway so it wouldn’t have made much difference.

Chris’ comments made me think that maybe i could do it properly - measure how much the seat was ‘off’ from the centre line of the steering wheel and engineer the brackets properly - sorting the seat belt holder in the process.

So the other week-end I started measuring

Image

I put a spirit level under the steering wheel as well to ensure I was looking at the bottom of the wheel but the upshot was that the seat was offset by about 25mm

I did a similar measurement with the pedals
Image

So this week-end I’ve finally been able to get on with it.

the recaro brackets appear to be made from 5mm steel and I had a leftover plate of that lying around from a previous project.

Stage 1 was making up extenders that would allow me to create new holes 25mm further in towards the centre of the car. At this stage i wasn’t sure if the rear left bracket would even have room. I also wanted to create a working version as a proof of concept - once I knew it would work then I’d weld up the brackets properly.

I’m also acutely away of how important safety is in relation to these mods - hence my intention was to over-engineer it to make sure I’d got no worries on that front.

So this is stage 1.
I made the 4 initial ‘lozenges’, drilled and tapped a thread into them and screwed team into place. - this was just to see if I’d have enough room - especially on the left rear bracket

Image


Stage 2 took it a bit further and hopefully you’ll start to see how it is meant to work

Image

So I welded another piece onto the original ‘lozenge’ and this meant i can bolt through the original fitting into my new lozenge, and eventually I’ll drill and tap a new hole in the sticky-out bit.

As you can see there is a gap between the existing bracket and the new lozenge. this is because both pieces have an 8mm thread cut into them, but as they weren’t cut at the same time they don’t line up - so there is a gap between the two. that’s not acceptable going forward but it allows me to create a proof of concept - I’ll be able to rig it all up, sit in the car and if I like it I can make them fit properly.

the solution to fitting them properly is to drill out the thread in the original bracket to 8mm so that the bolt goes through there and into the thread on the new bracket and pulls the two pieces together tightly.

I didn’t want to drill out that original thread at this stage in case it didn’t all work.

Also please note I’m not just going to be relying on bolting on an extension. the new bracket will be welded (and bolted!) to the existing one so it can’t go anywhere.

The next issue was to drill a hole in the new piece with a centre that is 25mm away from teh hole I’d already drilled and tapped.

I carefully marked out where to drill, then marked it again in a slightly different position. then i punched a pilot dent in the wrong place and punched another pilot dent in another wrong place, ending up with this

Image

I could see it all slipping away from me at this stage - if each of the holes weren’t exactly 25mm away from the originals, or at different heights then the seat would be liable to be skewiff.

Thankfully I took a few deep breaths at this point and went and had my haircut.

On reflection I realised what I needed was a jig I could use each time. I was able to mark out the holes to be 25mm apart. I drilled one hole to 8mm, and teh other to 4.5mm - that would be for making a pilot hole - the 8mm would be for locating it on the new bracket with a bolt.

Below we have one of the new brackets at the top, the jig at the bottom, and on the right a space and bolt to help assemble it all

Image


It goes together like this
Image

That allows me to drill a 4.5mm pilot hole exactly 25mm away from eh existing hole. I was then able to widen that to a 6.8mm hole which could be tapped out to 8mm.


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Last edited by sladey on Sun Jul 12, 2026 8:27 pm, edited 1 time in total.
The simple things you see are all complicated
I look pretty young but I'm just backdated yeah
sladey
Nurse, I think I need some assistance
Posts: 9365
Joined: Sat Apr 23, 2005 9:08 pm
Location: Nottingham, UK

1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

This is one of the 4 brackets bolted into place
Image

I still couldn’t test it out without adjusting the seat belt holder. The existing bracket is made of 3mm steel. I like I said I’d got some 5mm lying around (but no 3mm) - I thought I’d try and bend that. It was a bit of a mammoth task, and also looked like a lot of work.

In the end I decided to have a go at trying to bend the existing bracket to the right place. In case it wouldn’t work I ordered some 3mm steel as well so I could make a new one if it didn’t end well

Image

However a bit of heat, a large pipe wrench and I was able to move it out of the way
Image

Later I was able to bend the end bit back to a more vertical angle
Image

Then I was able to assembler everything, put the seat back in the car and see how it felt

So how was it?

Well it felt pretty good - The wheel certainly seemed more central to my seat.

Image

The gear lever was obviously closer than before but that wasn’t a bad thing. here is fifth

Image

If that gets to be an issue I can bend the gear lever away.

Also right hand heater control fouls teh seat (but TBH not by as much as I’d expected)
Image

The end of it is already cranked towards the seat though so a couple of adjustable spanners and I was able to straighten it out
Image


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Last edited by sladey on Sun Jul 12, 2026 9:09 pm, edited 2 times in total.
The simple things you see are all complicated
I look pretty young but I'm just backdated yeah
sladey
Nurse, I think I need some assistance
Posts: 9365
Joined: Sat Apr 23, 2005 9:08 pm
Location: Nottingham, UK

Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

So having proved the concept it was time to weld it all up.

I wanted to make sure that as well as being 25mm apart, the new holes were level with teh existing ones so I came up with this setup

Image

I then welded everything up and ended up with these
Image

I then blasted them Image

And am currently waiting for the paint to dry
Image

I’ll fit the seats tomorrow - looking forward to my first drive….


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The simple things you see are all complicated
I look pretty young but I'm just backdated yeah
jury
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by jury »

Love it Mark...overthink it, make it ! Though I do think you'll notice an improved difference with the new positioning
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sladey
Nurse, I think I need some assistance
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

Yep I’m quite excited about it - as soon as you mentioned it I thought- why not?

How far over did you move your seat?
The simple things you see are all complicated
I look pretty young but I'm just backdated yeah
jury
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by jury »

About the same...just over an inch. My seats are narrower and I don't have heater controls etc so can squeeze afew MMs more. (mutters something about every MM counts :) )

Hope all is well mate
# 465

1967 912 Polo Red
1968 912/11 RAL 7001 ' MOD ROD '
1990 964 C2 Velvet Red
1991 VW Vanagon GL (SOLD - Vanagone)
2017 Coleman CT200U

“It’s not where you’re from, it's where you’re at”
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