Jump to content

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


coalnotdole

Recommended Posts

Coalnotdole's Scimitar GTE: Fuel Injecting The Ford Essex

 

I've spent the last two weeks working on the Scimitar, ok I'll be specific: The red GTE (as I do own three of the sodding things.) I've been considering starting a thread about it for a while but I'm no longer sure it really qualifies as autoshite enough...? 

 

After all Scimitars are sort of a bit desirable now... well ok, they are not as worthless as they used to be. I've never actually done a thread on the GTE as I had sort of thought it was mainstream and classic car like for the forum, Though it did make an appearance at shitefest 2015 and does feature occasionally in the news thread and has even made it into the calendar! So it is maybe at least a bit AS?

 

Anyway I'll let the forum decide, If no ones interested I'll stick to posting about Rebels and SS1's. I can promise though that this thread will feature the following key elements:

 

A Plastic Shooting brake form the early 70's.

Spending far in excess of the value of the car on fixing / modifying it.

A reckless disregard for the sensible use of money.

The worst paint job in history*

An engine tuned up by former Williams F1 engineer,

Complicated Electronics that I don't fully understand,

Fibreglass work and Welding,

A daily diver that only a total masochist would bother with,

An opportunity for it all to go spectacularly wrong...

 

I should probably take the opportunity at this point to fill in some background history on the car. I bought it in 2010 as a non running project. I'd never owned an old* car before instead I generally drove end of life modern bangers all of which I'd driven into the ground (some of them literally.) I'd admired the Scimitar since I saw one decaying in a yard where my dad went to get his cars serviced, They slipped from my mind until one day I was in an abandoned foundry in Ipswich and came across a discarded book on cars ( I think it was Clarksons top 100 cars or something like that,) In amongst all the exotica was a Scimitar and suddenly I was reminded of that car I'd seen years before. A few months later my mk4 Astra terminally shit its gearbox and fuel pump in the space of a month, Pissed off with the disposable nature of modern cars I got thinking about the Scimitar. Surely a fibreglass bodied car with a solid chassis and an over engineered British V6 should be the Ideal car? It won't rot, should be reliable and any problems should be fixable with a piece of chewing gum and a bit of string...

 

Naturally at this point I went on eBay and because I didnt know what I was doing (or looking at for that matter) I inevitably bought the worst Scimitar project available. The engine bay had been on fire and badly repaired with steel, the wiring loom was missing, The chassis needed a total overhaul, the suspension was fucked and the brakes only existed as parts in a bucket! Somehow with my mate Dave's assistance we managed to put it back together and against all the odds in 2011 It went back on the road and did become my everyday car.

 

The GTE in 2011

199.jpg

 

It benefitted from rolling improvements and as an when I had spare cash bits were steadily enhanced to improve reliability. Generally, it was pretty good and fail to proceed incidents were rare enough, certainly rare enough for me to keep my job in any case.

 

By Spring 2016 and suddenly there were a few clouds on the horizon the engine felt tired, it was down on power and had an unfortunate tendency to run hot. It was rough at Idle and Recently the oil pressure has seemed a bit low. In short I sort of suspected it was a bit fucked. (though it was still good enough to get me done for speeding on the M4 eariler in the year...)

Here's a recent-ish picture of the car:

 

368.jpg

 

The engine was the one that came with car when I bought it 6 years ago. Its not original to the car and I haven't done a huge amount to it in that time, save for fitting a set of unleaded heads with roller rockers (as the push fit studs kept pulling out.) and fit a steel timing gear. Its done quite a few miles since then. hard to put a figure on it as the odometer is a bit erratic, certainly more than 60,000 though. Not too bad for a random second hand engine.

 

 

I'd always known the engine was going to need attention before long and I'd horded a decent amount of tuning bits, as well as 2 complete 3.1 Essex's. I had intended to put together a decent fast road oriented 3.1 but as a project it had more or less come to a halt at the parts acquisition stage.

As I started getting the parts together to build up a new engine I found my focus creeping towards trying to get a touch more power out of the Essex. the figure of 185ish ft lb of torque with around 200hp appealed. This is a reasonable enough figure but to get there your probably going to have to change to either a Holley carb or a triple weber setup. My GTE's an everyday car rather than a weekend / track car so the concept of mid teens on the MPG was enough to get me to think twice about going down that route. A few years back I became aware of the Samcor EFI Essex and that begged the question was it possible to squeeze extra performance out of the Essex with fuel injection, with the additional benefits of modern electric control and reliability....

 

I did consider going down the alternate engine route but ruled it out in the end. Mainly because an alterative engine would have meant having the car off the road for too long while it was fitted. I've noticed that scimitar engine conversions appear to rumble on for years and very few actually result in a car thats actually in regular use. There are exceptions to that but It was enough to put me off an engine swap. Added to that I actually quite like the Essex... controversial I know! in my opinion it suits the car, the torque and power are usefully delivered and the gearing is pretty good. With the engine a long way back the weight distribution is not bad either. Reliant came up with neat enough arrangement in the engine bay, even finding room for the spare wheel. This tidy packaging solution is something that is often compromised once you start swapping engines. Add to this I much prefer the idea of enhancing the original concept rather than binning it off.

 

So as well as acquiring spares for an engine rebuild I'd started planning an EFI conversion, I put out feelers to try and locate a Samcor EFI setup but, given how rare they are the chances of finding one of those seemed remote, so I'd decided to use a triple weber inlet manifold and triple Jenvy throttle bodies. These were to be fitted to a balanced 3.1 with a fast road cam. I even got as far as buying a megasquirt ECU and starting to think about trigger wheels when I came across an engine for sale which was very similar to the engine I was about to build.

 

The engine for sale was a 3.2L Stage 4 Essex, which had done less than 2,000 miles since it was rebuilt. The seller had bought it from Specialised engines and was about to have it installed in his Capri, when he realised it was difficult to turn over. He sent it to another specialist who then rebuilt it a second time This time round The top end was sent to John Hoad , former Chief Technician at Williams F1. He reworked the heads and inlet manifold before the whole engine was put together and fitted to a Capri. The engine was installed and went in to Northampton motorsport for tuning its Triple Carbs. They suggested to the owner that It would run better on fuel injection and so they Fitted triple Jenvy throttle bodies with pico injectors running of a Omex 710 ECU at the end of last year.

The entire setup was available complete which was important as on paper at least it should be a bolt on setup. Saving a vast amount of development time compared to building a new engine from scratch to a similar spec.

 

Hence I found myself talking to the seller and was able to put a deal together to by the engine. In the process recklessly blowing the entire respray budget (and a bit more)  on engine, fuel pumps, ECU, Loom, coil packs etc....!

 

Here it is on the way home:

 

368b.jpg

 

Heres a few pictures once it was home on the stand…

 

369.jpg

 

370.jpg

 

 

A rough outline of the work to fit this engine looks like this:

 

Fuel Tank modifications,

Fuel Pipe replacement,

Installation of Fuel Pumps & filtering,

Swap the engine to use a front bowl sump & timing gear,

Baffle a front bowl sump,

Fit the new engine,

Installation of a stand alone wiring loom to connect engine / ECU / Coil packs and injectors,

Find room in the engine bay for a fuel pressure regulator, coil packs, etc

Connect it up and get it working!

Link to comment
Share on other sites

Wowzers. Sounds ace! 

 

Like you, I reckon the Essex is a great lump in the Scimitar. Loved the torque in mine. Just didn't like the Scimitar bit so much.

Cheers DW, I seem to remember at the time that you may have been unlucky with yours needing some front end work?  possibly Vertical links? i think in the end you may have sold on before it became an issue but can't remember the details.

Link to comment
Share on other sites

Brilliant, I think any thread that is fundamentally about doing stuff to an actual car is acceptable on here BTW. What mpg have you been getting with the old engine??

 

Before it was fucked it got 28 to 30mpg on a decent run, less round town more like mid 20's. The scimitars quite high geared and does have Overdrive!

 

Recently the mile counter has been broken so Its harder to calculate, Economy definately suffered as its health decined and i spent more time trying to thrash it to get any performance out of it. Maybe nearer 20mpg.

 

I will hope for high 20's out of the new engine.

Link to comment
Share on other sites

That looks like a serious lump of an engine! Look forward to the progress.

 

Like you I love the Essex. Sounds good, easy to work on and puts a smile on your face. And that's just in standard form...

 

I sold my Scim too soon, I may have to revisit one day with an SE5...

 

I'll be keen to hear how you get on with the management, that would be the next step to getting more power out of the Locost as chips are thin on the ground these days for its standard ECU.

Link to comment
Share on other sites

It will be a shame to install that engine, I'd just want to look at it; although I suppose you could fit a Perspex bonnet

LoL.....put a glass top on it and have it in the lounge as a coffee table.

 

Anyhoos, a good number of years back, when 3.0 Essex engines were easy to get hold of from the scrappy, a mate of mine had Burtons' build a 3.1, 6 pot monster for him, which then went into a Capri......

.......All was very fast and furious for a couple of weeks, then the gearbox blew. No problem, back to the scrappy and a replacement soon bought and fitted..................which barely lasted a week....... Time for an uprated box, which I believe started life in a Transit flat bed, or something of that ilk. 

 

All is deep joy,......................for a couple of weeks.............the next big bang was the diff..........No problem, back to the scrappy and all is soon fixed...............for a while........2 or 3 months if memory serves.

 

The solution was either press lighter with the size 10, or motor sports for a stronger unit, with LSD. Limited slip was much needed anyway so mucho wedge and several days later it emerged from their workshop and all was good.

 

Thing is CND, make sure your transmission can cope with all the extra grunt, or it could get very expensive.

Link to comment
Share on other sites

Just brilliant. Do you ever attempt something and not give 100% effort by the way?

If you mean do I do everything the most difficult, expensive and overcomplicated way then yes....

 

I like essexeseseses too, my 6a is dependant on Kseal so if you're selling any spare lumps I might be interested

I've probably got a spare if you get desperate.

 

Thing is CND, make sure your transmission can cope with all the extra grunt, or it could get very expensive.

The scimitar has a Salisbury rear axle which has a reputation for robustness so I'm not too concerned about that, the gearbox was rebuilt about 18 months ago it's got a few upgrades in it too such as steel selector forks. The brakes were also upgraded to vented discs earlier this year. The cooling system will be done at the same time as the engine.

 

Next post will cover the fuel tank...

Link to comment
Share on other sites

Sorry this post isn't as exciting as a shiney engine...

I was aware when I stared going down the Fuel injection route that I was going to need to modify the tank to allow for a fuel return. My car has a stainless tank fitted already but as it has been used recently it was still partially full of petrol not ideal for welding to. I was lucky enough that someone in the scimitar owners club had one spare, they are available new but they are not exactly cheap. Fortunately the replacement had been dry for a number of years. I gave it a good clean out and sent it off to get a fuel return line welded in:

371.jpg

However I did a bit more reading online and it turned out there were a few other things to consider. Modern cars generally have a tank breather on there somewhere to prevent air pressure problems, the scimitar as standard vents through the filler cap, but I was unsure if this would be ok with the extra flow through the tank. So while the tank was out I decided to also modify it with an extra outlet for a breather valve. While It off It was also decided to modify the fuel filler neck to have an air breather line. The new line will connect the top of the tank to the top of the filler neck and should allow the air pressure to equalise as the tank is filled. It should hopefully prevent the clicking off problem you get at some modern petrol pumps while filling up.

372.jpg

The Pressure Release Valve is a Newton TPV8 This is designed to remain closed until the air pressure level is reaches a set level, it then opens. This should prevent the tank from constantly venting a petrol smell from the car, only opening when need. If it does spend a lot of time open and there is a noticable smell I'll look at fitting an activated charcoal filter like you get on modern cars. This should be easy to retofit at a later date.

373.jpg

The filler neck has had a BSP Boss welded into it to allow the hosetail to be removed, it allows the retaining nut to pass over it with reasonable clearance.

374.jpg

The boss sticks through into the filler neck a bit too much at the moment but it will be filed down before its properly fitted.

375.jpg

I then fitted the tank, filler neck and bypass hose to the car to test the theory. Its in a difficult area to photograph so please excuse the shit pictures:

376.jpg

The hose at the top left will go to the pressure valve, Which will be hidden somewhere under the boot floor and the outlet from that will be run out somewhere under the car.

377.jpg

I took this photo showing a potential location for the valve, I think i will actually move it back towards the filler neck and only the output hose will come though here, but It shows the theory.

378.jpg

Cheers

Joe

Link to comment
Share on other sites

The fuel system continued....

 

With the tank sorted there was still the problem that I had to find room for all of this stuff:

379.jpg

(Low Pressure Pump, High Pressure Pump, Fuel Filter and swirl pot.)

I knew I'd have to alter the tank but had just sort of assumed that it would be easy to loose the fuel pumps under the car somewhere, but after scrabbling around under the oily horrible mess that is the bottom of my car I realised that it wasnt quite as simple as that. A few options were explored, including mouting the pumps in the dead space above the passenger side boot floor, that location was ufotunately close to the rear silencer which was hardly Ideal, My mate Dave suggested replicating the Middlebridge setup, with the pumps mounted alond the inside of the chasss rail, which would probably have worked ok If it wasnt for the swirl pot.

Middlebridge setup:

380.jpg

The Middlebridge setup also had the disadvantage of covering all of the pumps in filth and oily muck that inevitably accumulates on the under side of my car. While I don't do the paris-dakkar on my daily commute I do use the car, year round and have driven it through Flood, Ford, mud and snow often enough to know how much shit can get stuck to the underside of the car.

After a bit of head scratching It was decided to sacrifice the rear Jack cubby hole and recreate it as a home for the pumps, at least the pumps would be protected from the elements and servicing would be easier. I'll work out a way of putting the Jack inside the spare wheel at a later date. At least then it will be in the same place as the spare when you want to use it!

Dave got happy with the Zippy disc / demolition saw:

381.jpg

A wooden mould was made, Filled and sanded:

382.jpg

waxed:

383.jpg

Given a PVA coating:

384.jpg

Gellcoat: (application of gelcoat on a coupe is optional)

385.jpg

CSM:

386.jpg

The mould had to be destroyed in order to get the new section out, unfortunately the filler was a bit old and hadnt properly gone off so some of it stuck to the moulding, Still it will clean up ok. With a moulding complete it was possible to start mocking up the layout for the pumps, this would allow us to create captive nut plates in the places we needed.

387.jpg

Dave welded up some nut plates to suit, the steel is actually spare coupé door reinforcement which we had lying around, WWRD?

389.jpg

Glassed in:

390.jpg

391.jpg

The Gelcoat then strangely turned black... ok I scraped the shit off it and primed it.

392.jpg

I'm reusing the entire setup that came with the engine the only real alterations are to the unions, banjo fittings and to the fuel filter.

393.jpg

All the fueling parts layed out in their final locations.... The components sit quite low in the box, this is to allow a decent layer of sound insulation to be attached to the lid, I'll also insulate the back of the boot carpet so hopefully the noise of the pumps won't be heard in the front of the car. The space to the right of the high pressure filter has been left deliberatey to allow working space for changing as fuel filter and to allow somehwere to put a multilug connector for the rear wiring loom,

394.jpg

395.jpg

The fuel filler lines will probably come through a grommet here but I wont drill it until the new pod is fitted to the car.

396.jpg

And finally heres a last post showing roughly what it will look like with all the fuel lines, There is actually a technical error in this photo so full marks awarded if you can spot it.

397.jpg

Link to comment
Share on other sites

Great update, cant wait to see it running.

 

With the plug for the moulding, next time seal it with 2 or 3 coats of emulsion to seal the wood pores, then use wax, then a good thick coat of polyvinyl alcohol release agent, dont know if which kind of PVA you put on but if its the wood glue type then its no wonder it destroyed the plug.

Link to comment
Share on other sites

Great update, cant wait to see it running.

 

With the plug for the moulding, next time seal it with 2 or 3 coats of emulsion to seal the wood pores, then use wax, then a good thick coat of polyvinyl alcohol release agent, dont know if which kind of PVA you put on but if its the wood glue type then its no wonder it destroyed the plug.

 

Cheers Honey badger, The mould making was done in a bit of a rush over a short weekend so there wasnt a huge amount of prep time, The PVA is a proper release agent of some sort, I bought it from the local boat builder a few years ago when we were doing some grp work to one of the rebels. The decanted it from a huge drum into a tiny plastic bottle. So I'm not 100% sure what it is or its use by date so possibly its a bit past its best. The cheap greek body filler used to fare the mould was probably far more of an issue as it diddnt want to set. This particular moulding is probably one of the least nice things we've made, still it should do the job ok.

 

I always try to take photos when doing grp work as inevitablty its something that lots of people want have a go at, but are put off after bad experiences using the kits sold in motor factors (which are often total shit.) I buy all GRP supplies from out the factory gates of the local boat builder or the local chandlery. 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...