412 BHP...THAT WILL DO NICELY......

[CHANGES]

but you also mean head flow smoothing, so blue printing the head would assist power...the std engine I understand wont take much more than 350BHP without some physical mods...seems odd to me that but can only listen to what I am told by the likes of PUK...I am certainly going to install their 350 bhp chip stage 6 ready for a complete engine rebuild and tune up...maybe?  all depending upon whether I can get the chassis and the brakes up to scratch..

with the engine mods how have you found the other items, brakes and handling...

 

Hi Paul,

In reply . Head flow smoothing is just that, removing the rough surface to reduce the laminar layers

improving the flow quality, More drastic work like changing the port size and shape will be needed to

sustain better power delivery. Just as important is the rest of the induction system, (as covered earlier)

if that is not up to scratch then any head work is wasted.

The work you say you have done on Ford units in post 268 should bare similarities, You only need to

do the calculations for the flow parameters etc required to get the VE results you desire and machine

from there..

 

The BHP that an individual engine can take will vary on build quality and spec. From my experience

the 89 onward std 910 is a very strong unit. It took 10,000 miles of aggressive use at over 400 BHP

for me to break it, even then only from component weight.

 

I am always skeptical of chips which have no dyno data with a comparative engine spec.. They may

give you more power but how and at what cost.. The trouble is the alternative can be very expensive..

 

For the tuning you are looking at, the chassis if in good order will be fine, (maybe a tad flexible).  The

brakes however can be an issue. The system you have on the S4s is covered in a thread by Darren,

following this will enable you to get the best out of them. There are also several upgrade kits available,

PNM is a good starting point..  I eventually settled on vented large disc 6 pot front along with larger

vented 4 pot rears..without any ABS ,  simple and very effective. Adjustable suspension professionally

set up should give you the handling you require.. There are many options available and threads covering them..

Hope that covers your questions. 

 

   I think there is a market for those Wheel arch extensions, if you want. I could cetainly do witha set.

How do they attatch?

Cheers, Jacques.

 

The arches at present are just concept. They are being tested and will be developed during this year.

At present they are fixed by just 5 self tapping screws under the arch so as not to damage the original

paint work. This fixing works well, my previous S4s/V8 after market type used this method without incident. 

 

the splitter, is that a special made one or something we can purchase...definitely need one of them as mine is gone and no one seems to make original spec ones...

 

The front splitter fitted is specific to this Esprit and part of the complete aero floor pan. There are others

who have made similar which just bolt on..  

 

I Have PUK chip 6 fitted and gives great power but only useable in short bursts as the higher boost gets the air too hot and the boost then drops away, and thats with lots of mods to charge cooler and intake. The only way to cure it is to go bigger on the turbo, which is why I am now running the same hybrid as Dave. I can now run 1.0 bar boost rather than the 1.2 that chip 6 gives and still get more power whilst maintaining a steady charge temperature....it`s going on the dyno soon and I`ll let you know the results!

 

Hi Lee,

I am pleased to see some of the developments filtering through with positive effects. It will be very

interesting to see your dyno data and results. It should give feed back on the # 6 chips ability.. It

would be a good idea to get the technician to independently monitor knock, lamba, and advance..

rather than just doing a power run.. This will enable you to see if any safety features are dropped

out within the chip to allow it to provide the advertised performance..

 

Thanks for the appreciation Chris, Do you think it will be worthy of one of your Build Books when finished ?  

[CHANGES]

Clutch, Torque and traction

 

From the beginning of this upgraded rebuild it was clear some power and torque development

would be expected.  Projected figures showed a torque rise that would exceed the present

paddle clutch system..  Previous use of  the paddle system with the GTO box had also

showed excessive ware with a judder on pick up and down shift..  This created the classic

catch 22 situation where this system was acceptable with the standard box and needed for      

the engine’s power.. But inevitably then the box broke and the clutch was not suitable long term

with the new box….. So, even before the situation for engine re-development was encountered a

new organic alternative was on the drawing board.  This new set up was to be the Cosworth RS500

clutch with modification to fit. This would however require a concentric slave cylinder to cope with

the release loads.. Fitting all this in was a major challenge..

First I had to design a special flywheel which would site the clutch as close to the engine as possible.

To maintain a required thickness for handling heat , the rear oil seal housing needed thinning

down and the counter boring of some fixing bolts.

 

 

The fly wheel was designed to reduce peripheral weight so that the extra mass of the new clutch

was compensated for and suitable inertia figures retained for smooth drivability without slowing

throttle response.

 

 

Fitting of the concentric cylinder was another matter.. The bell housing needed extensive work

machining out material and welding in a suitable mounting platform. During this operation some

extra space could be created  to accommodate the clutch set up height and ware clearance..  

Unfortunately it still needed a 3mm spacer plate between the box and engine to accommodate.

 

 

When all finally completed it fitted well with the desired ware clearance as shown in next pic.

 

 

On initial testing the peddle loading was more than I wanted for a daily driver, so some changes

in the master cylinder were made along with peddle travel and connection position..  Eventually

I achieved what I required..

On test drives the clutch engagement and gear change were spot on . It was only dyno set up

power runs that we came into problems. This was not a fault with the clutch but that the engine

performance that exceeded the torque limits..  I am still driving it now with the engine turned

down and loving the feel. Developments  to find a replacement clutch which can take the full

engine power with the drive-ability I desire is ongoing.

Because the projected power and torque was higher than before, when traction was already a

problem especially in the wet, I decided to activate one of the features in the new ECU….

Proportional traction control , with 5 settings. That along with a torque biasing differential has

given much more control in all weathers..   This will take a while to finalise the exact

proportional settings I desire.. I feel a lot of number 11’s and drifting is needed..

 

The only other change to date is the overall wheel track width. This has been increased by

2” overall on the front and 2.5” on the rear.  The purpose was to lower the roll center and

increased stability with the projected power.. All the  testing so far is very positive but a lot

more is needed to finalise the set up..

 

This covers all the new changes so far, I will update further developments as they happen. 

[ragingfool35]

Dave

did you install a VR on the other wheel to utilize your TC?

[CHANGES]

I have chosen Hall sensors as better results have been seen when using this type of ECU.

I placed one on all four corners to get the most accurate feed back. It was not possible to use just the rears due to ATB differential upgrade as part of the new spec. 

The set up is not fully completed yet as I need a facility to test and adjust the % for each of the 5 settings. This will probably happen after the new twin plate clutch fitted over the winter break...   

[ragingfool35]

i am interested in pics of the rear sensors and sprocket if you used a non-stock setup.  my ECU has TC capability as well.

 

[CHANGES]

Sorry for delay getting back with this but been busy..

The sensors are positioned to pic up on the ABS/speed sensor trigger wheels on the rear drive shafts.  For the front I fitted the later ABS trigger wheels which just press onto the hubs..  The only machining required was some drilling to allow access where not available..

 

The sensors used have an LED which indicate correct functional positioning . Nice time saver..     

[CHANGES]

Clutch, Torque and traction  .... part 2 ... Twin Plate Solution.

After all the changes needed getting the Cosworth clutch to fit and work i was under no apprehension this was not going to be straight forward.  Trying to get the same peddle feel and smoothness was going to be a tall order.

There was no other road option I could find, so after consultation on the V8 twin system with AP racing engineer we decided to work with that.  After quite a bit of internal component spec changing they came up with a bespoke design to carry the torque without exceeding a realistic release load.    

Dimensional convenience was another aspect that pushed me towards the V8 twin system.   Bell housings on the two models although completely different in appearance have identical depth clearance . The main bone of contention was the flywheel face heights, which is considerably lower on the V8 ( closer to the back of the e-block)..  Fortunately my previous flywheel design for the Cosworth set up  had already compressed this height to the max. which was slightly more than required for the V8 set up..  So with a dimensional possibility and torque compliant, it was decided to give it a try..

Flywheel design again had to be changed, this also gave the opportunity to work on the inertia figures to improve throttle response.  The standard fly weighs 7.2 kg with high peripheral loading , the new design has reduced peripheral mass with gross weight of only 3.9 kg..

Standard 910 S300 fly

New replacement twin plate design

The standard 4 pot clutch assembly weighs in at 7.5 kg , as does the V8 assembly. An added advantage on the V8 unit is it is a more compact unit with smaller diameter and lower inertia properties. . When combined with the new flywheel the total set up height is identical to the V8 combination.

Now we have got it all to fit in , the actuation mechanism needs changing to suit. The old push hydraulic system needed inverting and the clutch arm changing for the pull type.  

 TBC... 

[CHANGES]

Continued....

Above is pic of changes and components needed to complete the conversion.. 

Point 1 ( far left ) , the original actuating arm opening is lengthened by 25mm 

Point 2 , this is the fulcrum mount for the arm, this remains the same height as the original but is 10 mm closer to the center shaft. this is simply installed by welding and machining an extension to the original. This will accommodate the fulcrum pin ( item bottom right ) 

point 3, This normally has a raised section which requires removal to create a flat mount for the pull bearing guide tube.  ( item top right )  This also requires two fixing point tapping in.. By machining this down it means the tube will sit 8mm lower than the standard set up. To insure that this does not create slack in the pull bearing another tube was made 8mm longer.  The inside of this tube was also customised to be an exact fit over the original thrust bearing tube. A small relief is also made to the bulge over the crown wheel to allow it to sit neatly down.  

point 4. This is to create a quick release bell housing.  Due to the nature of the twin plate set up, the gear box during installation does not have the movement flexibility of the old type, as a result the bell housing fouls the turbo. I decided to use this option as apposed to removing the turbo each time the box comes in and out.

Here we see it all pre-assembled.  The quick release section will normally remain attached to the back of the engine, when in position it is secured by the 4 fixings. 

The hydraulics system I have provisionally used is a 0.75 master cylinder with a 1.0 slave on a reduced peddle fulcrum , The feel is similar  to the std V8 which is encouraging considering the  590 ft lb torque capability of this system..   

Mounting options for the slave cylinder were limited. I did not want to to machine the box itself , also I wanted to make the bracket so it can be mounted to any box with ease.

 

I settled on this design which is held in place by two fixing points, both are very sturdy and work to resist the forces exerted on them.. 

   

An adjustable push rod machined to match the arm socket finished the set up.

So far limited road tests have been carried out without incident.( 20 miles,)  More aggressive testing this weekend before a strip inspection to confirm everything is doing what it should..    

[CHANGES]

On 20/02/2016 at 16:18, CHANGES said:

The hydraulics system I have provisionally used is a 0.75 master cylinder with a 1.0 slave on a reduced peddle fulcrum ,

Update..

After some quite aggressive testing on Sunday, all was good.  However in stop start traffic, the take up was a bit sharp. It took a few more rev's than I would prefer for smooth pull away. This was not helped by the tall 1st gear. So as a result  I decided to alter the hydraulics slightly.  I changed the master cylinder to a 0.625 but maintained the rest as was.   This has given a more progressive peddle with a much better feel..  After tests today it would seem this is the best cylinder ratio set up. ..  The gear selection is really good with only normal rev's needed for smooth pull away. A very slight drag on selecting reverse when hot appeared,  similar to what a lot experience...  I can increase the peddle fulcrum point to elevate this drag if it does not abate after bedding in.. ...Just need to get some miles on it now.. ..     

[CHANGES]

On 18/10/2015 at 03:22, ragingfool35 said:

i am interested in pics of the rear sensors and sprocket if you used a non-stock setup.  my ECU has TC capability as well.

 

Just going back to this question.   The answer I gave which indicated the use of the ABS trigger wheels from the S4 onward models will need revising..  Yesterday saw me back at Northampton motor Sport to review the ECU system along with session of wheel spinning to set up the traction control...  During these tests we were getting some bad data from the trigger wheels.. After some investigations it appears the sensors fitted are not fully compatible with such a fine toothed wheel.. The system does and is working on cars fitted with trigger wheels with less teeth.  So that is the next thing to do.. I will update when I have the spec that works..

All the other data logged on the ECU was spot on, so no changes to be made there.. Now the clutch does not slip under power it is an amazing feel.. In fact it is so nice I may not boost it any further (at the moment) Just refine the rest of the Esprit..   

     

[MrDangerUS]

Dave,

Ingenious..., simply ingenious!

Could you please touch base on your new engine management system?

 

[CHANGES]

Update on Traction control 

Further tests did show the sensors were picking up two teeth at one time at various speeds. This was the cause of the ghost signal problem.. In the first pic. you can see the new 12 tooth wheel against the 48 tooth ABS standard unit. Quite a difference. 

The second pic. shows the new trigger wheel fitted in place. I used the same interference friction fit at the ABS wheel, This was the most convenient method and saved any extra fabrication .. Direct exchange.

The rears created a different challenge.. It was not possible to fit the same 12 tooth trigger wheel due to the restrictions provided in hub design.. Eventually I decided to remove every second tooth from the existing trigger mechanism ..  This proved to be quite adequate and provided a perfect signal with 24 teeth.  The next two pic's show before and after machining. 

When setting the sensors it became very apparent the difference. Previous the distance away from the trigger wheel was .010'' and would drop signal within .002'' either way.  The distance is now .030'' with .020'' tolerance either way. On manual rotation you can see how much more positive the signal strength was.   

Finally a trip back to N'hampton to program in these new trigger wheel values and test set up .. I am pleased to say it was 100% and tested up to 140 mph..   A dwell up to 10 mph was programmed in to allow controlled spin start, This also seems to work well with the take up on the various traction control settings.  The present setting are same as NMS programmed into there race cars so may need slight adjustment later after road testing..(but so far so good.)  This TC seems to be a nice little addition to the Esprit and takes the worry out of those snap spin ups.. 

     

[silverfrost]

Are you looking at doing a GT1 replica as those arches look awesome in the first photo 

[Sparky]

Conferred on me today was the signal honour of test driving Dave's car.  What an experience!

The engine is astounding.  Dial it down and it's like driving a new car: smooth, relaxed, perfect.  Then turn the dial to 11 (naturally) and you're in charge of a monster.  The torque, the boost are just mind-blowing.  And the work he's done on the suspension is incredible.  I've never driven an Esprit remotely like it (and I've driven plenty).  You really need to be paying attention to the gauges as you're taking bends at breakneck speeds in an instant, and it's absolutely effortless.

It made my run home in the GT3 seem a little pedestrian.

I could go on about it for ages, but suffice to say it was a unique drive in a one-of-a-kind Esprit.  Excellent work, Dave. 

[MrDangerUS]

David, I couldn't find it... would you point me to your UN1 rebuild thread?

[CHANGES]

Hi John,   Sorry for slow reply, The thread you are looking for is   UN1 More torque-ing points.!

 

On 3/29/2016 at 02:17, MrDangerUS said:

Dave,

Ingenious..., simply ingenious!

Could you please touch base on your new engine management system?

 

 

The system now in use is from  the Life Racing F88 range , with various add on's.. This is the same manufacturer who supplied the system for Lotus's LMP1 race cars.  It is far more compatible with my final build spec, providing better data logging also with control facilities for extra's like the traction control along with turbo phase and anti phase boost control setup. etc etc..  

 

 

 

 

 

 

[MrDangerUS]

Dave,

 

Any updates on the clutch project?

[ragingfool35]

hi Dave

i think last we spoke i indicated a method for fuel cooling i was going to try.  this $75 AISI 316 coil is made for dialysis on the fuel return line.  Just installed it.

 

[CHANGES]

On 2017-5-27 at 22:41, ragingfool35 said:

i think last we spoke i indicated a method for fuel cooling i was going to try.  this $75 AISI 316 coil is made for dialysis on the fuel return line.  Just installed it.

Now that's a nice none invasive ,compact, low cost alternative..  well done Chris, clever use of natural air flow..   do you have any before and after temp data yet.  

Dave

 

[ragingfool35]

sadly no.  i missed the perfect opportunity on the 500 mile drive to LOG37.  Im not sure what instrument would be suitable to measure the temp of the fuel in the tank.  I thought i could remove my tank drain plug and put something short in there, it would also need data logging capability...seems like more effort than i want to expend lately.  If someone is interested in the PN and wants to run an experiment, i will dig it up and provide.

how did you measure yours?

[Vulcan Grey]

I've measured the temperature of the plastic fuel lines after driving, and they were over 200F if I recall correctly...

[Jacques]

Most interesting.

Oh, that is quite hot. Maybe I should install a probe and measure mine, a plastic and a braided line to see, if any radiated heat wil affect the fuel temp negatively.

Since I know nothing about this interesting topic, I am just throwing a few thoughts out as supplement: thermal isolation between enginebay and fuel tanks, thermal isolation of fuel tanks themselves, thermal isolation of fuel lines generally, ram air to cool fuel tanks as in fast moving air feels colder than still standing air e.g. when bicycling, the air stream passing your knees will cool them Down, let's call it a sort of chill factor. I don't know if this is all nonsense, or maybe someone already did it all? Interesting topic anyway.

Kind regards,

Jacques.

[CHANGES]

Jacpues,  This is an area I confronted but without reading this whole thread again I am not sure how much I posted about it.. 

But to summarize,  The fuel circulating in the Esprit system will rise in temp from ambient.  The layout does little to suppress it.  The lower the fuel level gets the hotter it gets, which in hot countries on low fuel will cause performance irregularities.  During the changes I made we addressed fuel supply requirements for the higher BHP levels. Doing this exposed just how hot the fuel could reach, In my case we had it boiling in the swirl pot..  Hence the introduction of the fuel cooler which is detailed somewhere. All of this is of little interest to those with basic tuning but the fringe studies will be.  

When studying the re circulation of the fueling system in std form , the o/s tank ran several degrees hotter than the n/s.  We also exposed that the fuel on the tank exit pipe was also considerably hotter than the ambient tank temp.. ( These are average figures over varying times and conditions. )  Prior to the fuel cooler I installed a ram air circulation system around the tanks to try and reduce the temp rise.  I simply did this by forming a ram duct under the tank over the circa 3'' hole in the body which already there.  This did have a slight effect but was limited to vehicles speed and use. However even though the tank temp stabilized  slightly the exit pipe temp showed very little reduction .. I guess the ram system was not able to drop the tank temp sufficiently to have an appreciable effect.   The next step was the fuel return. this was in effect the heat source..  It was directly next to the pick up which is why the exit pipe temp was higher than the tank temp, along with any increase from any pump function.  So I then redirected this into the n/s tank .  This had the most dramatic effect.  What we saw was the n/s tank hotter than the o/s , a reversal from before , more interestingly only by a small margin..  The tank exit pipe temp now dropped to the same as the o/s tank which was also considerably cooler than before.  The fuel temperature rise in the tanks was so much slower than before, to begin with I thought along with the ram air cooler I had cracked it, but alas over longer journeys the temp rose especially in traffic.  This never reached the temps I had seen previous but still had higher readings on lower fuel levels. 

Lower fuel temps can increase performance by helping the VE  and having a more consistent fueling delivery.  The standard ECU does not have fuel temp monitoring system so will deliver the same pulse of fuel regardless. When the fuel is hotter it is less dense so less is injected..   The amounts we are talking about are minuscule and will not be really noticeable on a daily drive.  But as part of a tuning package all these small percentages add up to make a huge effect as this thread will testify. 

So in brief does ram air tank cooling work ,  in a fashion yes..  ( there is a few other points that need be considered, that are not mentioned if thinking of undertaking, along with more effect ways of doing.  ) 

Hope that clears any area's that may have been missed..

Dave..    

 

[Jacques]

Thanks Dave, and for clairifying the idea about redirecting the return pipe. Makes perfect sense.

Another point of interest for me at least, is weather the installation of the tubular exhaust manifold being made of thin 321 stainless steel, raises the fuel temperature by it's (thin) design and type of alloy, or the potential increased exhaust gas speed will counteract this effect? And if so, I guess for example exhaust wrapping the tubular exhaust manifold would lower that heat spread in the area, and potentially send it out of the exhaust system via the rear silencer?

One thing I noted upon the installation of the Sport300 turbo etc. on my own SE Esprit was, that the chargecooler temp dropped fairly much. I therefore also isolated the underside of the chargecooler (slightly) and raised it a Little and it became a bit cooler still. But that is another story.

As always, your work, testing and observations are most interesting.

Kind regards,

Jacques.

[ragingfool35]

what would be a good way to measure the fuel temp?  a thermocouple in the tank sump drain fitting?  i see them only for diesel.