What'll she do, mister? - Rolling Road results

[campbell]

Just back from the nice people at Dastek, Dalgety Bay, clutching my laminated holy grail...new RR graphs

Fergus organised a day there a while ago, probably quite soon after they started out, and believed they had a good set up and reliable RR calibration etc. It's actually a 4x4 rolling road, so popular with the Jap importers obviously.

So decided to use them for Before and After runs during some minor mods which Robin is helping me to do.

My S1 has been essentially standard since the word go in 1999, and sports only:

- K&N replacement panel filter
- Stainless sports exhaust (Motobuild supplied)
- Trophy 160 52mm alu Throttle Body
- Cat still in place, albeit original so probably a bit lighter now!


2 full power runs completed, revealing...

• 132bhp at flywheel (107 at the wheels)
• 129 lbft (175Nm) torque
• Peak power at 6000rpm
• Peak torque between 3100 and 4900 rpm
• Decent path of air-fuel mixture across rev range
• Minor spike in mixture richness at 3500rpm - with similar 5 lbft loss in torque

Graphs attached below. The "standard" 1.8 K is meant to offer...

• 118bhp
• 122 lbft (165Nm) torque
• Peak power at 5500rpm

...so the results in themselves are quite reassuring. I do know that UJI was putting out a bit more than standard even when fairly new back in 2000, in a session at AVA, Glasgow. But good to see that has been preserved!

Dastek are keen to sell their "Unichip" interceptor ECU device, however until Jedi Master Robin has been convinced of its integrity, I am not the least bit interested. These results show the MEMS is just fine for standardish cars, and we will see how it can perform once my upgrade is complete. Robin's runs showed strong results from his latest upgrade, though, however failings might be being uncovered with the Lotus K4 chip for running modded cars...but I'll let him tell you about all that!

£47 for the session, took best part of an hour per car. Plus some blethering in between obviously. For H&S reasons, Dastek are not mad keen on you viewing the whole affair, but once set up and safe, they will allow one visitor to the test cell for one of the runs if you ask.

[robin]

Mine made 160 at the engine @7000rpm, similar dip in torque around 3,500 (be careful not to make too much of that dip though - if you look at the power chart you will see it makes the tiniest dent in the overall performance - the scale of the torque graphs exaggerates the "problem".

As far as I can tell the Unichip is essentially a tricked up resistor of power. That is not to say it cannot work, but they were very vague about how it works - it doesn't direct drive the injectors - instead it relies on fooling the ECU into changing fuelling somehow.

I only did one run because the ECU is underfuelling pretty much across the rev range at present, with matters being worse the higher the revs. So I either need to go back to getting the emerald working or look at increasing fuel pressure a little to fox the ECU back into working properly.

Cheers,
Robin

[campbell]

Yes, absolutely not hung up on the wee torque dip, just interesting to be able to see such things and understand the "why". Haven't spent such a pleasant Monday morning in a long time!!!

The chap doing the runs themselves seemed to know his stuff, was talking about various features that can affect the graphs and that he has done quite a bit of work with vernier cam pulleys to tune the power peak etc more finely. Not so much how much power you can get, but quite where to have it arrive in the rev range...eg to avoid that extra upshift at Knockhill etc!

Anyway, the session did what it said on the tin for me. Now let battle commence...

Oh, and I stopped by MMC on the way home to get my floorpan inspected. Yours truly is getting a Stage 2 warranty repair, ie like Tut 2, new floor panels, on 12th March. So nice n shiny for Donnie

Campbell

[Bob vanM]

there is a way to get that torque dip out of the system

[Bob vanM]

sorry, could not resist

[robin]

You might just be able to keep up now, but try to make sure the car goes round the corners

Cheers,
Robin

[hiscot]

Robin what spec have you got
what mems are you using @ 160 it must be close to its limmit ?
graph would be nice to see

[robin]

Robin what spec have you got
what mems are you using @ 160 it must be close to its limmit ?
graph would be nice to see

I'll ask Campbell to do it for me as I have no digital imagininjary skills.

Spec is that it was a S2 135R, so the base ECU program (not MEMS - it's the S2 lotus/EFi/whatever ECU) is a bit different.

That means it already had the alloy plenum and I assume the larger TB (hence the different ECU program).

I replaced the head with a K16 with 31.5mm inlet and 25.5mm exhaust valves plus extensive chamber mods and flow improvements. Flow bench results (in cfm per 50thou lift) are:

Code: Select all

Inlet
Standard: 17.9 38.5 56.2 73.5  79.2   80.8  83.9  86.1  86.6
EGOR:     22.2 46.1 69.9 92.8 111.3 118.97 124.6 127.4 128.8

Exhaust
Standard: 14.5 29.0 41.5 52.7 60.0 64.7 65.6 66.2 66.2 
EGOR:     16.7 37.6 55.7 71.2 79.5 85.1 86.0 88.5 89.0 

I'm still running standard cams, so not using the full lift or duration - the head could clearly flow a lot more gas than 160bhp worth.

I have fitted a piper 4:1 manifold speculatively - I couldn't say whether it influenced the figures at all.


Intake is standard airbox and panel filter, cat and back box are also standard (though I have a sports cat to fit at some point when I get around to it).

I suspect with proper fuelling there may be just a wee bit more than 160bhp to come out of this setup.

I am considering switch to the LE1811 cams (probably the pikey regrind as I cannot really see why not to go that way) - these add an extra 10 or so degrees of duration and nearly 4mm of lift which will allow me to exploit the hgher flow rates from the head better. I would expect perhaps another 10bhp that way?

I cannot do anything more until I sort out fuelling, so I may have to refit the emerald, wide band lambda kit and do some mapping. But I hate the fact that these are mapped on throttle-angle rather than airflow, so I am not fully committed to that route - ideally I want something that works with a MAP or MAF and "fools" the standard ECU into doing the right thing with the fuel (or takes over driving the injectors in the first place).

I really want to develop my own box of tricks for this and have got most of what I need to do it - I just don't want to cut the wires, but maybe I'll bite the bullet and do that - I can always source a spare intake manifold loom I suppose if I want to revert to standard and cannot make good the wire breaks.

It's very driveable at the moment - much more so than the 165 kit I had on the S1.

Cheers,
Robin

P.S. Campbell, check out:
http://www.dastek.co.uk/images/power_ch ... ZR_105.png Note the dip in the torque curve at 3,500 before AND after unichip Yep, it's for a K16 engine ....

[hiscot]

Robin I went regring 1811 cams ported head ect
the cams are brilliant and give a good tickover due tolift rather than duration + 20+ bhp from std cam However with a ported head it was too much for my mems
( your later eu3 is reprogramable to a fashion inc fuel and ing from test book I believe ) (Theirs also some one who makes conversion looms for the emerald )
so went dta then wide band however you cannot run map with any high lift cams due to pluses or something according to my mapper hence i now run tps and load and it works great i also use bario and the lc1 ajusts acording to readings inc heat soak from the a/temp sensor thats now fitted into the air box as it was too close in the ptp t bods and warmed up nicely
the mems went into default and over fueled and the car stuttered on throttle , my mapper said he could map it on a single t bod but with multi bods you will gain shed loads of midrange and better overall running
my restriction is my std valve size the cams can del a lot more than i have but flow is at max i have approx 177- 180 on a safe mapyour head should del more
bob

[Rich H]

and breathe...

Good stuff!

[robin]

Robin I went regring 1811 cams ported head ect
the cams are brilliant and give a good tickover due tolift rather than duration + 20+ bhp from std cam

But I probably have gained a lot of this by making my valves much bigger, so +10bhp probably more reasonable estimate for my current configuration. If I get +20 I will be chuffed, though!

However with a ported head it was too much for my mems
( your later eu3 is reprogramable to a fashion inc fuel and ing from test book I believe ) (Theirs also some one who makes conversion looms for the emerald )
so went dta then wide band however you cannot run map with any high lift cams due to pluses or something according to my mapper hence i now run tps and load and it works great i also use bario and the lc1 ajusts acording to readings inc heat soak from the a/temp sensor thats now fitted into the air box as it was too close in the ptp t bods and warmed up nicely

Common problem the S1 alloy plenum had the same problem; the S2 places the IAT sensor along with the map in a plastic insulated sensor away from the head - it remains at more-or-less ambient all the time (or cooler if there is moisture in the air due to wind chill ).

Agree on the MAP vs racey cam thing, but with a cam and crank position sensor and suitable software you should be able to filter out the pulses (you know when to expect them because you know what the cam angle is) provided the sensor itself has enough bandwidth. The other option is to run MAF instead which is mostly immune to the pulses as it's miles upstream from the valves.

with multi bods you will gain shed loads of midrange and better overall running

I have some DTHTBs but no space to actually fit them and proper air box - at the moment I am going to be happy exploring the limits of the standard TB and air box.

my restriction is my std valve size the cams can del a lot more than i have but flow is at max i have approx 177- 180 on a safe mapyour head should del more

Of course it's diminishing returns - once you have high lift cams, you get less from big valves and vice versa. If I can get a smooth idling car and ~170BHP from this relatively simple setup I think I will be more than happy. At that sort of power output your piston life is reduced (assuming you track it) already - at 180 and beyond you should really think about forged pistons, etc., at which point you should really be thinking about more CCs too ...

Cheers,
Robin

[campbell]

[quote="robin]at 180 and beyond you should really think about forged pistons, etc., at which point you should really be thinking about more CCs too ...
[/quote]

...and more £££s as well I imagine

I suppose we could start exploring bottom end developments for when mine lets go, right enough ... I

[robin]

It's horses for courses Campbell - a brand new bottom end for a 1.8 costs 1.3K (retail) plus fitting costs. But the pistons will still be suffering from day one if you have too many horses. [Which you won't ]

An overhaul for your existing block and crank to give it forged rods, pistons and new bearings plus the labour is going to be say 1.5K, but obviously the time with the car off the road is much longer, and you face variable costs for fixing liner height issues, machining the block, etc.

So once you've bitten off the whole rebuild bottom end thing, you might as well go for more CC and then at least you know you'll be paying for new liners, block machining, etc.

Cheers,
Robin

[campbell]

OK so the results are in...

Reminder of std Elise stats:

• 118bhp
• 122 lbft (165Nm) torque
• Peak power at 5500rpm

My spec BEFORE = 132bhp

- K&N replacement panel filter
- Stainless sports exhaust (Motobuild supplied)
- Trophy 160 52mm alu Throttle Body
- Cat still in place, albeit original so probably a bit lighter now!

Only change - installation of modified head courtesy of Sabre Heads and Iddon Engineering ...

2 further power runs completed today, revealing (previous results in brackets)...

• 147bhp (132) at flywheel, 120 (107) at the wheels
• 135lbft (129) torque - or 183Nm (175)
• Peak torque at 5300rpm (4700)
• Peak power at 6000rpm (6500)
• Peak torque band between 3100 and 5400 (3100 and 4900) rpm

Decent path of air-fuel mixture across rev range

Still has minor spike in mixture richness at 3500rpm - with similar 8 lbft (5) loss in torque

Graphs will be uploaded by my Race Engineer, Robin, via Dynoplot

But the upshot is, Sabre's "mild spec" head is very well worth the £400 investment (and of course about 5 long shifts in the garage!). The car felt immediately more driveable when we finished the work, it gets right to the limiter at 7k no problem in 2nd and 3rd gears. Indeed, 3rd gear is now my Warp Drive overtaking weapon (yes I know other cars have true warp drive but this is quick for a feardie like me OK!).

No discernible loss in low or midrange torque, nor change to fuel consumption. Just a great build up from midrange upwards

One happy customer. Thanks also to the fellas at Dastek for today's RR session and some extra data outputs to help us with plots etc.

Campbell

[Lawrence]

What was my guess again