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S4s,S4,SE UPDATES & IMPROVEMENTS

55K views 269 replies 36 participants last post by  Erik L 
#1 · (Edited)
S4s UPDATES & IMPROVEMENTS

OK, many of you probably took a wager how soon I start modifying my new car.
Yep, here we go...
Improvements and upgrades, of course, why not... I'm not going Ape-ballistic like on my 88"ET, though.
Who won the bet? LOL.

FYI:

Rear hatch support Struts-hold open

On Amazon, price $20 -$40 on Prime/pair
Search for: LIFT-O-MAT or Sachs Stabilus, Liftgate Lift Support (4F-484474) by Stabilus®. Body Connection: Plastic Socket with Ball Stud. Shaft Connection: Plastic Socket with Ball Stud. Compressed Length: 11.811". Extended Length: 19.685". Travel Length: 7.874". Capacity: 79 Lbs. UPC: 194879010212. More details on - Stabilus® 4F-484474 - Liftgate Lift Support

Also acceptable are BOXI 6938, Gas Charged Universal Lift Supports Struts Shocks Springs Dampers. Extended Length 19.70 inches, Compressed Length 11.75 inches, 75 lbs Force,10mm Ball Sockets.
If you have additional weigh, like glass hatch and/or wing you need 95 lbs force, look for Boxi 4279.

Front Bonnet hold open strut is shorter:
free Length 18.25"-18.75", compressed 11.5", 45-50 lbs
Sachs 083666 (45 lb), or perhaps Boxi BX54657 (55 lb)


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#169 · (Edited)
In real life, the "obvious" is not that obvious!

I's obvious, that that performance of the engine will improve when incoming charge temperature is lowered. This gain is worth almost ~0.7 HP/ 1 degree F in the linear band of the characteristic before turbo efficiency drops.
It's obvious, that making a chargecooler colder will work to our advantage. Higher coolant volume flow is critical, so is a higher volume and pressure (electric) pump.

So, what is not obvious, you may ask.
Well, if we ask a question "what size is the intercooler feed line on Esprit" , 90% answers will be 5/8".
Except, the laminar flow in 5/8" system delivers perhaps only 10mm stream of coolant!
Upon a closer examination, components of our CC bcooling system have much smaller internal diameters and generate a huge resistance to flow.
For example, our metal 5/8" tubes actually measure 12.5-13mm and hoses 14mm I.D., or less.
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> Laminar flow occurs when the fluid flows in infinitesimal parallel layers with no disruption between them. In laminar flows, fluid layers slide in parallel, with no eddies, swirls or currents normal to the flow itself. This type of flow is also referred to as streamline flow because it is characterized by non-crossing streamlines <<
The common application of laminar flow would be in the smooth flow of a viscous liquid through a tube or pipe. In that case, the velocity of flow varies from zero at the walls to a maximum along the center line of the vessel. The flow profile of laminar flow in a tube can be calculated by dividing the flow into thin cylindrical elements and applying the viscous force to them.

Under conditions of laminar flow in a viscous fluid, the velocity increases toward the center of a tube.
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Q: How we can improve flow of coolant to C/C on our cars?
A: By lowering resistance (R) of the whole system

R=8nL/3.14xr^4

Let's compare fluid of the same viscosity flowing in the same tube length(L) in three different pipe diameter circuits.
a) Assuming, the "base" is (so called) 5/8" dia OE system, which consists of ~12-14' of 12.5mm metal tube.
b) If we increase diameter of the tube to 3/4" (16.5mm I.D. cross section), the resistance goes down 3 times! 65% improvement.
c) If we further increase diameter of the tube to 1" (21.5mm I.D.), the resistance will be 8.8 times lower! A whopping 88% improvement!

Even if we don't change the I.D. of the inlet nipples on C/C and HE, a much larger volume of fluid will be presented at the inlet of each!

Concluding:
an upgrade of the OE C/C circuit to 3/4" or 1" dia tubing/hoses offers immediate benefits without increasing the boost limit.
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Here is Dave's ("Changes") CC with 1" in/out.
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and his installation
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#190 · (Edited)
In real life, the "obvious" is not that obvious!

See posting #169


Well, if we ask a question "what size is the intercooler feed line on Esprit" , 90% answers will be 5/8".
Except, the laminar flow in 5/8" system delivers perhaps only 10mm stream of coolant!
Upon a closer examination, components of our CC cooling system have much smaller internal diameters and generate a huge resistance to flow.
For example, our metal 5/8" tubes actually measure 12.5-13mm and hoses 14mm I.D., or less.
When you design your plumbing for the chargecooler, be aware that sharp bends create large pressure drops:

90 degree elbow
wide radius - 0.07-0.1 psi
sharp elbow - 0.26 -0.3 psi

45 degree elbow - 0.04 psi

Also, straight section of tubing introduces pressure drop depending on its length, diameter and velocity of the media,

according to this equation

calc.png


d Pipe Inner Diameter (in)
l Pipe Length (ft)
v Water Velocity (ft/s)
∆p Pressure Loss (psi)
μ Coefficient of friction
SG Specific Gravity
 
#170 ·
It would be interesting to pull the exit tube loose and measure the volume out for a given time and then put the larger tube on the inlet side and see what the difference is. I fear the constriction through the CC would be the limiter?

Speaking of CC. I saw recently that Alunox is coming out with a stock size CC that is I am sure much more efficient than the OEM. Be curious to see the specs when they post it on their web site.
 
#173 · (Edited)
Possible overfueling cyl #1 and #4 at WOT?

PO had a silicone vac hose failure at the T located under the chargecooler causing excessive IM oil mist ingestion from the crankcase vent system. Walls of the IM plenum were thick with the oil deposit. When I opened the plenum, I saw a strange "wash" pattern.
Secondary injector spray cone is "shrouded" by the injector nest bore edge resulting in poor fuel mist distribution.
Countermeasures applied: enlarged diffuser slot and chamfered injector bore edges

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#174 ·
Nice!

Great welding. Love to see before and after dyno plots to see what changed. I wonder if it improved the torque curve etc. Does it run smoother, idle better?

Oh wait those injectors dont come on until you are into the higher RPM/Boost ranges so no change in Idle.
 
#178 ·
WARNING: ESPRIT FUEL LINES ARE a FIRE HAZARD

If you don't want your Esprit to look like this poor fella below, REPLACE the black plastic fuel supply lines with AN6 steel/Kevlar braided lines.

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It is a small, but very effective investment.
If your line becomes "mis-routed", it will rub against adjacent components and burst.
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It should look like this
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Preferably all fittings black or red.
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#179 ·
Oh My I was bending those black lines around the other day. Thinking they were a bit fragile.

Do you have a BOM for the Aero quip so I can one and done on the order?

Or do any of the parts houses provide a solution off the shelf? I will have a look around.
 
#185 · (Edited)
Hmm, I believe that's my car when I did it a few years ago. Ramspot und Brandt have the supply line kit. They don't offer a return line kit. I would be very interested in seeing a return kit or at least info on where to get it.
I use the R&B supply line kit with no ill effects so far. I am aware of the extra wrinkle(one full turn) on the original plastic lines, so that they can move about a bit in case of engine movement and possibly the car flipping over. But in that case, you have other problems. And hopefully the inertia switch will help too. No guarantees though.
I attatch a few more pics of the work. Sorry for the dirty and rusty bits on the pictures. They were all changed afterwards. Before installation, make sure all connections are done, so nothing is loose. Use aluspanners as here or tape up to protect wile working on them. Have fire extinguisher ready (big one) ready. Prime pume a few times and look carefully all over for leaks and dripping/spraying. Look at all hoses and connectors regularely. Personally, I couldn't find the right bits to make a return line set, so as stated above, I am interested in acquireing such a set if it's done by someone else knowledgeable. I installled the kit some 5 years ago, and it works fine. Although lines are quite stiff, there are enough slack so that they can move a little bit when engine is moving. Now I'll install poly gearbox mounts.
I did at the time also get a nice similarly kit from R&B for adjusting the fuelpressure on my SE, but didn't install it yet, as they wanted me to drill a hole/thread in the intake plenum, and since I wouldn't do that, I had to find another intake plenum set, which I did. That kit becomes a part of the return setup. Yes, there are aluminium tanks beneath the connectors. No leaks or problems with those either, now being 8 years old, I'll inspect them this Winter. Ps: I ONLY use 100 octane Shell fuel with little or no cowpee in it - less corrosion - lesser problems. I've taken off the fuel lines on my Corrado G60 and renewed them all, Nothing to seeon the outside, but the inside were hiding a star-shaped cracking all over - near destruction. So better safe than sorry.
Cheers,
Redfox.

Hmm... The webpage mixes all the pics up in an incorrect order. Oh well...
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Technology
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#189 · (Edited)
No idea, it could be a custom made adapter. Pump thread fitting is metric M14, the other end has AN6 male thread. Not your typical combination.
 
#191 · (Edited)
Adjustable Fan Thermostat

Derale switch 32F to 240F with thermo probe.
Precise and very competitively priced (eBay $20-$30)
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[/TD]
Adjustable Fan Thermostat
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#193 ·
Look for "DERALE Radiator Adjustable Fan Thermostat Switch" on eBay, $20-$30. Effective, precise and inexpensive.
 
#194 · (Edited)
Esprit fuel return line

Ideally, IMHO, the fuel return line should be plumbed into the left tank.

Currently, OE return line dumps warm recycled fuel right into the right tank close to pump inlet port. Meanwhile, fuel in the left tank is stagnant, cold and contributing... nothing. Elevated fuel temperature has an adverse effect on cylinder fill ratio. Actually, cold fuel in the left tank does not circulate. After a couple of "hard runs", Dave L. ("Changes"), reported incidents of fuel boiling up in the swirl pot of his car causing vapor locks.
 
#195 ·
This is a very good point @MRDANGERUS makes. It was fairly early on we found fuel restrictions on the power output.. Initially we used higher fuel pressure to overcome, but this lead to even higher fuel temp.. This in turn lowered VE and the cycle continued . Eventually a new set up with swirl pot and larger fuel lines put the pressure where we wanted it , but the temp issue persisted in the swirl pot .. What all this did show was how the fuel does heat up in the Esprit .. There is no cooling effect on the tanks and they sit adjacent a hot engine in a semi closed engine bay .. As a result we did tests which showed the fuel temp will naturally heat up on a journey even in a standard set up Esprit .. Fuel temp effects performance , so worth knowing ... This is an easy check any one can do .. You will be shocked at what you find in your fuel rail temp , and surprised by the tank temps.. By fitting the return to the left hand tank you cam slow down and minimise the temp rise , maintaining a more balanced performance for a simple mod.. On the more extreme side we noticed performance drop off with higher fuel temps so introduced a fuel cooler system, this worked very efficiently and we now see a consistent temp on fuel even on the long dyno sessions ..
 
#196 · (Edited)
TURBOCHARGER COOLANT RETURN HOSE

Turbo coolant return hose should be able to handle Super-Heated water temperatures.
Whereas water boils at around 212°F. at atmospheric pressure, if exposed to 15 psi (a common radiator pressure cap), the boiling point will now be 45°F higher. At this pressure, water boils at 257°F.
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. At consistently high temps, rubber and plastic (like overflow tank and spigots) deteriorate fast leading to slow leaks or larger failure.

Turbo coolant return spigot often cracks and falls apart. Thank goodness for steel inner sleeve, if it does not separate.
Spooxs Engineering aluminum tank is a perfect and reliable alternative.
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