1987 3.2 Carrera Backdate project - Sladeys hotrod

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sladey
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1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

Thanks Tim - I might have a play once new year is out of the way

Here's the manual btw
http://www.canems.co.uk/pdf/Canems%20DR ... 0ML1-X.pdf


I think they may have had a lambda sensor connected up but I don't have one so maybe that's the problem
The simple things you see are all complicated
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sladey
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

I think I'm going to enjoy this.....

First I compared the startup settings for the stock 3.2 and the tuned map. They were identical. After a bit more looking I found that the tuned map thought there was a lambda sensor connected and the standard one didn't. I altered the tuned one to tell it there isn't a lambda there (although I'll fit it later when I get a chance). Connected the laptop to the car and downloaded the new settings

Then I took it out for a slightly longer test drive - still wasn't able to really give it beans but the midrange punch has improved substantially. Don't really know about the top end as I couldn't really take it above 5K rpm. In fact it was driving beautifully all round and just felt noticeably quicker - the only downside being the tick over - it was idling at 1200 rpm. After engine got to temp then it idled at 1000 rpm - still a bit high

Got back into the garage. Initially I was looking for an idle control screw but on the motronic cars there isn't one - it's done through the ECU

So I went back to the laptop. There are a whole host of idle settings. Eventually I found that the idle valve closed loop control wasn't ticked and so I ticked it ( closed loop means that it keeps measuring whatever it is and adjusts accordingly, as opposed to just holding a setting regardless of what happens) Idle immediately dropped to around 900 rpm. Tried a few other different settings but none really made much difference so switched them back off again.

This looks like it's going to be fun!
The simple things you see are all complicated
I look pretty young but I'm just backdated yeah
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by impmad2000 »

That's the way Mark, fiddle and play !
Tim Bennett
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by targa boy »

Sounds like an interesting project on a car I have followed with interest ,and would love to see some performance comparisons when you have it all sorted.
As an aside you will find an idle adjustment screw with a 7 or 8 mm hex head just below the butterfly level on the throttle butterfly on all 3.2s if that helps, normally adjusted after shorting out a couple of pins in the plug on the engine bay relay panel if the normal Motronic ecu fitted which parks the IAC valve in a "Neutral" position.
Hope this helps.
Lee.
1972 2.4t(mfi and very orange) 911 targa,1973 bmw 3.0csl,1983 mk1 vw golf gti.
911hillclimber
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by 911hillclimber »

Not sure what your goals are with this, but very interesting.
I have a 110k mile untouched 3.2 with stock bosch ecu + Bob Watson chip from about 1999 in my 73T and it works and runs a dream.

I would be very interested to see if your car is even more drivable with such a mod as yours.

I guess an improvement in torque and where it peaks = 'drivability' (?)
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
sladey
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

Thanks for that info Lee. I'm happy to post Dyno maps when I get them - I'll try and book something next week with Wayne Schofield - provided he's OK using Canems stuff (though I might try and fit the lambda sensor before I take it to him)

Graham I haven't got specific goals - more power and more torque is a good thing for me. If I'd bought the kit retail then I might have been more concerned with exactly how much increase I'm getting per pound. However I got it at less than half price, and it moves me one more step closer to ITBs. I'm really happy with the result as it feels noticeably quicker - that may or may not translate into top line bhp but in the mid range it seems to be surging ahead.
The simple things you see are all complicated
I look pretty young but I'm just backdated yeah
911hillclimber
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by 911hillclimber »

I think that answers my question!
More mid-range punch (torque) is a good improvement in drivability imho. ease of overtaking or squirting between your favourite bends etc.

Look forward to the mapping bit.
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by corner shop »

Hi Mark, Shirish here - glad to read hyou've kicked this off and glad it was you that bought the kit as i know you'll make it work :)

I ended up getting a Motec M84 fitted to my Carrera by Neil Bainbridge, using TPS and MAP, coil on plug and sequential injection using the ASNU performance injectors he sells. We had to use the latter as the standard (batch fire) injectors couldn't cope and were running at 90% duty cycle when setup sequentially. I've got cold start issues too, possibly fuel supply related, so its back with Neil for fine tuning; runs and starts great when hot.

Will post the before and after graphs when i get them - the figures are not night and day, but the way it drives is very much improved, with crisper low speed delivery, stronger low-midrange, and improved throttle response.

I'm hoping your Canems offers similar benefits, i love the way mine drives now.
sladey
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

Hi Shirish,

Wow that sounds like quite some setup you've got there. Yours is 3.4 IIRC. Would be interested in seeing the graphs.

I'm going to get mine rolling roaded - the current setup was for another car so there will be differences. Also I'm not going to change anything for the moment until I've driven it every day for a week - that should let me start to for a pattern of what it is and isn't doing.

Having said all that I'm already loving the change - far more surge mid-range - plenty of torque. Starting isn't as consistently instant as it used to be but it has always started so far (will see what happens when the temperature drops though....). Power delivery is smooth with no hesitation or flat spots.

Cheers

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

Post by corner shop »

Correct Mark, mine is a 3.4 although if you followed my thread on IB.com you'll recall I've had engine dyno runs suggesting power and torque is way down against what it was producing back in 2009 - admittedly on a different chassis dyno but the figures were backed up other cars hitting the same figures on other chassis dynos. Will post the graphs once received.
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by goodtogo »

sladey
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1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

Interesting. May be a step too far though

.....but never say never
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
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

OK so having miraculously got my car booked in for rolling road with Wayne Schofield this Thursday I knew I wanted to get the Lambda sensor fitted before it went up to him. Plan was to get it sorted Saturday.

Everything was fine apart from:-
- didn't know where exactly it would fit
- wasn't sure how easy it would be to drill 2mm stainless
- wasn't sure how easily it would weld - never welded with stainless wire before
- didn't know if the unit would actually work
- whether or not it worked, didn't know if it would bigger up the maps I'm already running

So apart from all that I was quietly confident.
Saturday Morning, it quickly became clear where it was going to go - on one input branch of the muffler but pointing away from the muffler - whilst it's next to the engine it's avoiding the heat of the muffler itself.

Having marked the location, then took the muffler off and set about drilling a 23mm hole. My standard monkey-metal drills wouldn't touch the stainless

Image

Time for a trip to machine mart. Bought a handy dandy set of cobalt drills, along with a 20mm hole cutter to supplement the (unknown quality) 22mm hole cutter I'd bought from Wickes the night before.

Lo and behold the drills went through the stainless like the proverbial; even the Wickes hole cutter worked beautifully, just leaving a 22mm hole. A bit of die grinding later and I was left with this

Image


Then came the welding. Now I know it ain't real purdy, but to my surprise as I was tacking it in place I blew a big hole. I therefore had to build that up again. I was also aware that pinprick holes in the welds would affect the sensor's functionality so I went round twice to make sure there would be no gaps
Image

All connected back up
Image

I looked at the manual. Before first use you have to calibrate the sensor in open air. I tried to do that but it didn't seem to be coming to life at all. After thinking it through I revised this sensor has been in use on another car so decided to just fit it, and connect everything up

With all the wires connected up I went for a test drive. I also reconfigured the engine map to tell it that there was a lambda connected now.

The good news is that the car ran fine - no different really though. Bad new is that the oxygen readout on the laptop didn't seem to change. Well that was part of the bad news - the other part was the burning smell as I drove around the block. When I pulled over to check it there was liquid seeping out of a suppressor that had been wired into it.

There was a letter in with the kit I bought stating the previous owner had had problems with interference from HT leads - so they had wired in a radio interference suppressor box - that was now leaking some sweet tasting stuff that burned my fingers and was sticky.

I decided the suppressor was toast so I removed it and re-joined the relevant leads.

Image

Since then nothing has changed so I'm going to let Wayne sort it out on Thursday. If the sensor is toast I'll need to get another one but if so at least the fitting is all in place.

Currently:-
- Idles around 1200 rpm for the first 40 minutes of use then drops to 1000
- rev limiter kicks in at 5800 rpm even though it's set to 6800 in the software
- takes 2 goes to start it from cold
- pulls like a frickin train!

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

Post by DustyM »

Look forward to the before and after charts. Is it worth buying a spare Lambda to take with you, if you don't open the packet you should be able to return it if it's not needed.
sladey
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Re: 1987 3.2 Carrera Backdate project - Sladeys hotrod

Post by sladey »

Good idea - need to try and find a suitable wideband sensor in Sutton in Ashfield/Mansfield tomorrow

Google is my friend.....
The simple things you see are all complicated
I look pretty young but I'm just backdated yeah
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