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Coalnotdole's Scimitar - Machining work: Speedometer Drive Unit 12/4/19


coalnotdole

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Quality work as always on this thread.

 

This might seem like a stupid question but your baffle almost seems to fit too well almost to my untrained eye stopping the lower part of the sump refilling and the ford baffle had a couple of decent size holes to let the lower sump refill easier, is this deliberate?

It was something I considered, I've never done a sump baffle before so this a first attempt in that sense and I didn't want to over complicate it on the first attempt. what might not be obvious in the write up is that the full oil level is actually just above the height of the plate, so in normal driving it should still be submerged.

 

I've driven it and so far there is no signs of pressure loss, any problems and I'll be revising the design and making another!

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  • 3 months later...

Its emabarrasing how long its been since I updated this thread, I've sat down to do this on several occasions with the intention of continuing the writeup and each time I've found an excuse to do something more interesting! So I should apologise this chapter isnt all that gripping to read... It's hard to make air filters exciting! I'promise the update after this one will feature video of the car on the rolling road which is a bit more interesting.

Air Filters

Shortly after the engine went in I tried refitting the air filters that had come with the engine... Unfortunately it turns out the GTE has quite a bit less clearance at the back of the engine bay than the capri does...

The air horns fit ok....

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The base of the air filter housing fits less well:

 

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With the panel removed the base can be located in the right place, but theres still a clearance problem. I considered modifying the cover / bulkhead but it seemed like a lot of work to make a tidy job of it. I also didnt really want to start grinding fibreglass all over my new engine and having just fitted it I wasnt about to take it out again.

 

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I spent a while looking at the standard aftermarket filter options but most filters I found online were still to big to clear, So I started looking at other filters that could be modified to fit. I actually bought an ITG sock type filter only to discover it rubbed on the underside of the scuttle. Ford CVH type filter seemed a good fit but I wasnt sure if it would provide enough airflow for an Essex.

 

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A trawl through ebay and I came across a second hand Holley pankanke filter which looked good, The base would need alteration but otherwise would have been a straightforward option. As it turned out the forward edge would'nt clear the underside of the bonnet!

 

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A bit more ebay searching and I came up with another option from the USA, The dimensions looked promising but it would mean loosing the air horns but as I needed a quick solution to get the car on the road that seemed like a comprimise worth making. Also the price was quite cheap £38!

 

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Again to make this fit I was going to need to customise the base, Cardboard template time again...!

 

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I drilled off the holes on an aluminum sheet and could then work out the offset for the adapter, It sits as far forward as possible to give the maximum amount of clearance to the bulkhead and to allow room for the air temperature sensor at the front.

 

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Theres a bit of a gap in the pictures here but the adapter plate was mated to the cast base of the filter and this is the final result:

 

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I'm not entirely happy with the end result as while it looks ok I'm well aware that pancake air filters always draw in the hottest air in the engine bay. Scimitars by design do seem to have quite high under bonnet temperatures and these are definately something that could have a negative influence on performance. I plan on wraping the tubular downpipes and then I'll see how it performs in the summer...

In the next post I'll cover the trip to the rolling road!

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Excellent progress!  To keep hot air from your intake, is it not possible to do the same as the TVR S1 with its Ford engine?

 

 

Yes I could definately see a ducted air feed being tried at some point, the hardest part is probably deciding how to route it in a way that looks "tidy"

 

Perhaps a pair of those would be the answer to your underbonnet temperature worries ?

 

Thousands of 1990s boy racers can't* be wrong, you know...

 

They might* help but I could never fit anything to my car that looked that shit! I think the best set of extra vents I've ever seen on a GTE are these micra ones...!

 

Scimitar-GTE-SE5-modified.jpg

 

In reality adding vents to the bonnet or anywhere else is not really that high on my priority list... I quite fancy having the Dolomite spec front splitter, which is at least an established period modification!

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  • 4 weeks later...

By October 2016 I had finally got to the car to a point where I was ready to test run it on the road, the planned first run was to be a trip to Suffolk for a party. Dave came over form the IOW and we spent a frantic day finishing off some of the electrical bits, remaking battery connections, Earths and generally finishing things off... We loaded up with a boot full of kit and set off for a 3 Hour run the east coast. I'd probably gone about 5 miles before the car developed a lack of power problem where the engine got slower and slower, didn’t respond to throttle and at one point cut out completely. At the time there was less than 10L of petrol in the tank (we were out way to fill up when it started to cut out) Unsure if it was simply lack of fuel or a more serious problem we erred on the side of caution and took Dave's SS1 to Suffolk instead.

Here’s a picture of an SS1 where the GTE should have been!

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When I got home I filled the tank up and the problem never returned! Over the next few weeks I started using the car more, mainly doing the 23 mile round trip to work. I've been really pleased with the power and response from the new engine, it retains the unlaboured ease of a standard Essex, but has that bit extra on tap when you put your foot down.

In the first few weeks I noticed that the fuel consumption seemed quite high, IRO 15mpg. The Radiator fan seemed to want to be on a lot of the time too which highlighted that possibly the MAP / timing was in need of attention. The exhaust system, Air filter and coil packs had all changed since Northampton motorsport had first setup the ecu so a trip to a rolling road for some tweaking was due. I booked the car in with Devil Developments a local tuning company who normally specialise in fast Fords (usually with big turbo's!)

GTE waiting for the rolling road to be setup on cold November morning. :)

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During a long morning messing about, I noticed that even with a large fan in front the car the radiator fan seemed to want to be on too. Suggesting that there might be something not quite right with the cooling which would need attention. Despite this the timing was adjusted and the midrange fuelling was leaned off.

Here's a short but rubbish video of the car on the dyno, I missed the start of the power run but the video does catch the end of it at about 26 seconds in.



Here’s the graph showing the current numbers are 176.4 hp and 225 ft lbs of Torque.

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And for comparison here is the graph for the same engine when it was in the Capri:

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The horsepower figure is down a bit probably in part because of the missing air horns. I'm guessing the tubular manifolds have also helped with the gain in torque. There is a bit of a mystery about whats caused it to loose 1000 rpm at the top end,

Comments thoughts and suggestions on the results welcomed. I'm not an expert at interpreting power graphs so its hard to know what’s a good result and what else needs doing to get the best out of it.

After the rolling road I continued to use the car regularly and fuel consumption was considerably better back to the high 20's that I'm more used to. I still plan to fit O2 sensors to the exhaust to allow better control of the fuelling, possibly combined with replacing the tubular downpipes to do away with the ball joints which seem to be a weak spot for minor leaks.

Cheers

Joe
 

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Cheers, I'm pretty sure it is currently a bit restricted at the top end, Theres been a bit of speculation that the air filter could be the main cause, possibly also the exhaust system which is standard apart from the tubular downpipes.

 

I've just been looking through the video and came across this chart which is also quite interesting as it Shows the Air fuel Ratio plotted,

 

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It suggests an AFR generally between 11.5 and 13. Which suggests its still running quite rich (you can smell it tbh)

 

I diddnt know much about AFR so had to look it up, there is a helpful video about it on youtube:

 

https://youtu.be/EY78uPXvvY0?t=15s

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Air to fuel ratio should be above 14, cars with catalytic converters need 14.7 to be stoichometric or they poison the cat.  The fact that yours is running rich could the cause of running hot.but first it's worth checking the water pump, radiator etc.

 

Changing the manifolds, particularly the length is a likely cause of the torque curve changing.  You've basically built an Essex version of the LaFerrari's variable intake system, except the Ferrari can change it instantaneously and you've got to get the spanners out. :-D

 

Excellent work, this thread is a treat

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I thought that running lean caused excess heat? (On a 2 stroke at least). Does running too rich cause the same?

 

Good shout on the manifolds changing the torque characteristics.

 

Couldn't you do a dyno run with the bonnet open and a filter that wouldn't necessarily fit with with the bonnet closed for the purposes of experimentation?

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Running lean is less forgiving, if you're a bit out then cylinder head temperature can rocket, running rich has a lesser effect but still makes for less efficient combustion.

 

I'd definitely be checking water pump and radiator first.

 

Can you tweak the mixture while it's on the dyno? If so, I would be searching flor some cylinder head thermocouples and go there again. You used to be able to get ones that fitted under the spark plugs instead of the washer.

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Couldn't you do a dyno run with the bonnet open and a filter that wouldn't necessarily fit with with the bonnet closed for the purposes of experimentation?

 

It would definately be worthwhile doing a run with the air filter removed, Just to determine how restrictive the current filter is. At the time I did not think of it.

 

Can you tweak the mixture while it's on the dyno? If so, I would be searching flor some cylinder head thermocouples and go there again. You used to be able to get ones that fitted under the spark plugs instead of the washer.

 

The Mixture is defined by the Map and changes are generally made while maintaining constant speed on the rolling road and then testing the results.

 

After the rolling road I noticed it was loosing coolant too, some investigating and the issue turned out to be a weeping core plug just below the passenger side exhaust manifold, It was a right PITA to change which meant I put it off and did it between christmas and new years. It had probably been leaking since the engine was built. After the core plug change the running temperature did improve but there was still an issue with the effectiveness of the cooling fan but I'll cover that a bit more in the next post.

 

Water pump and radiator were both brand new during the engine installation and the radiator is an uprated ally one.

 

The mix is rich on the current map but this is in part to serve as insurance against the potential for running lean. When it gets some O2 sensors fitted to feed the condition of the burn back to the ecu it should be possible to safely lean off the mix a bit more.

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  • 4 weeks later...

With engine mapped I started using the car regularly, despite it being December there was still a problem with hot running. After a bit of investigation, It turned out that there was a leak from a core plug. I spent the day after boxing day scrabbling around in the wheel arch trying to get a car would work well enough to get me to wales for the new year. The core plug was hidden below the exhaust manifold, and the starter motor obscured access. Sat on a cold damp grass verge was probably one of the lowest points I've had during this project. Proof that even buying a nice engine and taking the time over the installation had can’t guarantee that things will always be a success.
 
Core plug sorted and I thought my cooling issues had gone away but as the weather started to get a bit warmer, I noticed the electric cooling fan was spending a lot of time on constantly at any speed under 35mph. The fan was supplied by the radiator manufacturer (coolex) and was newly installed at the same time as I fitted the engine. The fan is on a relay switched by the ECU based on input from a temperature sensor which is in a water gallery on the inlet manifold.

The new fan seemed to have a very low airflow and some experiments on the bench suggested that it was a pull fan rather than one designed to push. Most modern cars use pull fans as they are more efficient as the fan itself does not obstruct air entering the radiator. unfortunately, on a Scimitar the steering rack is immediately behind the radiator meaning that pull fans are difficult to fit. Reliant originally fitted a Lucas push fan to a cross brace in front of the radiator.
In the end I decided to replace the Coolex fan with a SPAL Push fan.
 
It certainly looks the buisness:
 
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Compared to the old one:
 
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The mounting points are slightly different and at some point in the future the brackets will need altering.


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In this picture you can see the crossbar in front of the radiator which origonaly had the lucas fan fitted to it.

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I also made some changes to the on off points on the ECU, its currently setup to come on when the engine temperature reaches 93 degrees and switch off at 89. The target operating temperature for an Essex is 90 degrees. Its entirely possible that these switching points are a bit low bearing in mind the sensor is in the inlet manifold rather than in the radiator which is more common. Thoughts or opinions on this welcomed.

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Cooling fans are not all that exciting, so as a reward for reading the above post I thought I’d share a few photos of something that recently arrived from South Africa…

Back when I was first thinking about Fuel Injecting the Essex I asked a South African contact in the Scimitar owners club to keep an eye open for a SAMCOR EFI setup. This injection system was developed by the University of Pretoria in conjunction with Lucas and was only offered on a handful of Sierra Models produced for the south African market. (The Sierra Saphire Ghia and the Ford Sierra 3.0i RS in case your wondering!) There were only around 1600 cars made using this EFI setup and they are almost non existent outside SA. Its Actually quite hard to find pictures of this setup online nevermind technical information about it!

Heres a photo that I did manage to find of the Samcor EFI setup in a South African Sierra.
 
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It came as a bit of a surprise then when Steve got in touch to say he had managed to find a SAMCOR Manifold & Plenum for sale and was I still interested? Given how rare the parts are I felt I couldn’t pass them up so 8 Weeks later I was looking at an alternative setup:


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I’ve had no particular experience with this era of fuel injection setup but it appears that its missing an A Lucas 5AM Air flow meter which I think will be the same as an XJ6 one.  I don’t have an ECU so would need to buy something standalone in order to run it, probably another OMEX 710.

Plenum

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I'm not sure what this is? it has no part numbers on it? possibly an air temperature sensor?

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I have no idea what Car I’ll fit it to, I’m not about to start taking the existing engine apart again. But at some point in the future it will be interesting to compare the two setups.

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  • 2 months later...

Its been a while since I've written about the GTE, I've not been that active on the forum during the recent ish spell of controversy but have been back on here a bit more in the last week and things seem to have really improved. :) Enough for me to have another go at writing about the GTE...

 

As the weather got warmer I became increasingly aware that there was something not quite right with how the engine was running...

 

Despite the upgrades to the cooling system (alloy radiator and uprated fan) the engine itself seemed to get very hot, Coolant use was minimal and there was no sign of contamination in either the oil or radiator cap. At the start of June under bonnet air temperatures were reaching staggeringly high temperatures the air temperature sensor measured as high as 79ºc while quing in stationary traffic. The car also developed a habit of cutting out when sat at idle; the revs would decline gradually over the course of a 10-15 seconds and would not respond to the throttle if constantly applied. Blipping the throttle would give a response and if you repeatedly blipped the throttle there would generally be a 'pop' which could be heard in the exhaust or the inlet and it would return to idling normally. This problem could also lag IE you could wait at a set of traffic lights and then drive slowly through a village only to have it affect you a few minutes later...

 

I was concerned about potential damage from preignition or detonation and even experimented by reverting to the original MAP that was written by Northampton motorsports, hoping that their advance curve may be better than the one from the rolling road but it did not make a significant difference.

 

A look under the air filer mid-June showed that something was clearly not right as there were soot marks present in the barrels of the throttle bodies and a brown petrolly film on the lid.

 

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With summer shutdown at work approaching I pencilled in some upgrades and bought two innovate wideband controllers the plan was to fit them and get the mapping checked and setup by another rolling road. Ideally coming up with an improved air filter at the same time.

 

On the first day of my 3 week break I went to drive over to Chichester to get some new tyres fitted... shortly after leaving home there was a loud bang from the exhaust, followed by a metallic noise when at midrange rpm… A quick look under the car showed the drivers side midbox had a major blow on the joint where the pipe enters the Silencer.

 

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I turned for home and had just pulled in when there was a large cloud of steam through the drivers side exhaust.

 

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Complete with a nice puddle of coolant dripping from the bottom of the tubuar manifold.

 

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Passenger side bank contamination, notice how the hot exhaust has burned the paintwork off the head!

 

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Gunk...

 

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To be continued...

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Not good news, easyish fix?

 

Still a work in progress... I'll sort some pictures out in a bit of what I found when I took it apart...

 

PS, Likes and comments are really appreicated as they help gauge if people are interested... It takes a while to write stuff up and it makes a difference if I know someone is reading it!

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