Jenvey Throttle Bodies On The Mi16 - The Results

[petert 586]

This thread is a typical example why POWER AT THE WHEELS is all that matters. You've jumped from 86kW to 100kW. Almost identical values to what I've achieved with similar setups. For me, 100kW at the wheels is 180hp flywheel.

[Banjo 1]

Chill out guys, why not just take it with a pinch of salt as they say and wait for Jon to get it on the track before slaging it off.

Ben

[Adam B 0]

This is all turning a bit mine is bigger than yours isn't it?!

Give a monkeys about 30+BHp more - its making one helluva a nice very loud sound

Roll on the next engine and bodywork lightening

 

sekim - the gearbox and tyres have changed btw

 

Oh and how do any of you know whats in that engine? Just remember it is French after all...

Edited March 6, 2006 by Adam B

[tom_m 0]

without coming into this on one 'side' or the other, i think the thing that has been missed is the temperature variation. the temperature in the dyno on the first plot is a good 7 degrees hotter, so a lot of the difference 'might' come in the conversion factor used to adjust each run to an imaginary temp. i know Emeralds corrected power graphs assume an abient temp of 20 degrees. you'll notice that the first graph is corrected UP to 170 and the second DOWN to 199. this, coupled with the different gearboxes/tyre combination and the different drag power used could contribute to the wide variation in power form stock too TBs/Motec.

 

it does however stand to reason that a decent engine is going to gain when breathing better and controlled by an uptodate management system, any fool ought to know this.

 

Can you actually prove that statement? The answer is probably no...The ECU's do all the same thing supply spark and fuel...

 

yes all ecus do the same thing, but all ecus are not created equal. if there was no benefit of one over the other then there would be only one ecu for all! granted one of the biggest factorswhen talking about a mapped ecu is the guy who mapped it, but unless they all use the same compnents and do things exaclty the same way, then all things being equal yes there is going to be variation between manufacturers of ecus there has to be. i was thinking exactly the same thing as Hilgie

 

 

anyway now thats all said and done, jon i'm glad its 'finished' mate, its seems like its been there AGES! hope you get to enjoy it soon, as paint guy says its the seat of the pants test that counts at the end of the day.

[hengti 2]

why do people always bicker over RR numbers??!

 

who cares?

who *only* point in RR tuning is in seeing that the systems are set up as well as they can be - ensuring that it's both reliable and efficient

 

we all know that roads vary massively and that the numbers are pretty much irrelevant

 

 

glad to hear you're pleased Jon - hope you enjoy it

[Miles 331 1 Cars]

Good results Jon,

Don;t forget you can get good and bad engines, Just look at the 1.9 8v or the 106 GTi engine for base figures

I got 199bhp from the Jenvey's, 90mm trumpets and 4-2-1 exhaust manifold as the std one is no good and nothing else.

It's down to how you build them so if I got any less from that spec I wouldn;t be happy

[petert 586]

Just remember, it's the numbers at the wheels that make the car move, or move faster. When you turn the key, put it in 1st and let the clutch out, nothing else really matters - a 16% increase.

[RHULPUG 0]

So, if a standard Mi16 on TB's makes 200bhp, then what should I expect when I rolling road my 205 S16, with high lift cams, TB's and NOS?

[RobMGti 0]

Wow how did i manage to miss this thread during the course of the evening.

 

Yet again im fairly shocked at how some of the so called "Senior, well respected" members of this forum show their true colours when a RR result is posted. Its embarrasing and is probably a reason why alot of people moved from other forums to here, because we dont expect to read that kind of stuff.

 

Sigh,

 

Good result Jon and i hope it will be on top form on the 18th. Any plans for a rebuild in the near future?

 

Rob

[Rob Thomson 6]

My tired, smokey, standard, 130k 1.9 Mi16 (albeit with a Maniflow manifold and system) made 172 BHP on the Powerstation rollers a couple of years back. And again, that was with what seemed like daft drag losses.

 

BUT, on the same day (a PSOOC rolling road day) there were a few GTi-6s and 306 Rallyes. None made more than 161 BHP at the fly, and they all had a good 10 BHP less than the mighty 309 at the wheels. I always thought I must have quite a special engine from the way it drove, and perhaps Jon has too?

 

I don't really give a toss what power figures people quote for their cars, I'm much more interested in other aspects of their preparation, and most importantly how they drive them - BUT Powerstation are local to me and do have a reputation for giving fairly accurate flywheel figures even if they're derived from dubious transmission losses.

[Baz 421]

Good for you Jon. Glad you're happy with it, as i'd be.

 

If i can just have my tuppence, can i just add, or remind, that while i don't pretend to be an engine guru at all, of any sort, every single tiny thing is a factor in a difference. No 2 engines can be compared, and a manufacturers' standard quoted power does not mean a thing, everyone knows they just take an average figure, sometimes you can get lucky, others not.

 

A good example of one factor is something i learned while my father and i helped out a friend of his for a couple of weekends, who was at the time No1 mechanic for PK Motorsport, a company that prepared and ran, amongst other things, Porsche 996 GT2's in the FIA GT series. Porsche themselves did a test to prove using not so good oil to run -in an engine works well, with 4 identical engines back to back, but again could never be a fair test, although the engines were identical. They were all run-in on an engine dynanometer, for 10hrs. Two on every day fleet oil, the other two on synthetic Mobil1. Afterwards, the two run on the s*it oil were both dyno'd at more than 25bhp more, (but one more so than the other) than the ones on Mobil1, which also gave very different figures between them. I know it's not alot on these engines but shows my point, as no 2 engines are the same. I found this very interesting and thought some of you might too, as yes can be very frustrating when you spend alot of money on an engine and then someone else claims to have got more, out of doing less etc. Thought i might aswel add it and hope it really is as interesting for some as it was for me, as, although i knew, never thought it actually made such a difference.

[Rob Thomson 6]

And another thing... it always strikes me as insane that people will spend a fortune on ported heads, cams, TBs and whatever other bits and bobs, but then expect their engines to exhaust through a bodged re-angled standard manifold and some god-awful cobbled together exhaust system. I reckon the 4-2-1 (and a proper system - ie. sensible bore, no aesthetic bulls*it) makes a big difference.

[Ryan 99]

Unless I'm working it out wrong the rollers have also "measured" a 30% transmission loss, which is clearly BS.

[Sam 4]

As I said on your other thread, nice figures. Bet it sounds the part too.

 

Just remember, it's the numbers at the wheels that make the car move, or move faster. When you turn the key, put it in 1st and let the clutch out, nothing else really matters - a 16% increase.

All very well and true, but, these figures can be incorrect too? Everyone seems to say "Its the wheel figure that matters", but who's to know thats correct??

 

Powerstation's rollers have been the subject of debate for ages, especially for dodgy losses.

 

At the end of the day, rolling road's are all a bit crap. A car that ran 200bhp on one set of rollers could be slower than a car that made 170bhp elsewhere. Look how well CW does with a supposed 150bhp!! Although that may be down (partly) to the driver.

Edited March 7, 2006 by Sam

[Guest BiFf]

Great result John. We HAVE to meet up one day as your car is running pretty much the same spec as mine (ie 45mm bodies, ECU (although mines an M3D not a uber-posh Motec), 4-2-1, and standard engine internals) I'd be really interested to see or compare the differences in the drive in the two cars.

 

Like you have said in the first place the figures are nice to look at but don't really count for much it' the difference between them thats more important to so you can see any gains, whilst trying to keep everything else as constant as possible (which reminds me I'm due a remap!!) I've had mine on the rollers before and got a reading of 171bhp and 170lbft, which seems very odd especially when the next car on (similar spec to ours) made a much more 'normal' figure on the torque. I don't drink so pub bragging rights don't mean much to me but you'll feel the difference when you drive it and that after all is the name of the game making your car 'better' or 'quicker'

 

BiFf

[maxi 36 1 Cars]

Maxi,

 

What do you John's new engine will produce on the same rollers? Shall we have a guess? 245?

 

 

Exactly Rob. Makes all of us who have spent a lot of money to get high in the power figurs look silly. We obviously only need a std wanked out 130K mi lump and a set of bodies mapped at power station.

 

I know of a VERY accurate set of rollers that tell GENUINE horse power. It near the M4 corridor, why dont we have a RR day and see what power we are all really making??

 

You do get good and bad engines, but not those that vary this much, normally its around 10BHP variation.

 

I get so bothered by results like this because it puts those silly BHP figures and thus, expectations for other poor people spending their money way too high. "That jon bloke on the 205 forum made 200BHP with a std lump and TB's.....mine is bound to make 250BHP with more compression and a set of cams" is what peple will be thinking.

 

As has been said, its all about the way the car puts the power down, although, I cant sit back and watch some post that they have picked up 30BHP just from a set of bodies. There was a large time gap between the original RR session where the std injection made 170BHP and this new figure. Anything could have happened to theose rollers in that time.

 

As I say, Im happy to organise a RR day on a proper set of rollers if you want to know what TRUE power it was making.

 

Maxi

[Hilgie 16 2 Cars]

it does however stand to reason that a decent engine is going to gain when breathing better and controlled by an uptodate management system, any fool ought to know this.

yes all ecus do the same thing, but all ecus are not created equal. if there was no benefit of one over the other then there would be only one ecu for all! granted one of the biggest factorswhen talking about a mapped ecu is the guy who mapped it, but unless they all use the same compnents and do things exaclty the same way, then all things being equal yes there is going to be variation between manufacturers of ecus there has to be. i was thinking exactly the same thing as Hilgie

 

I agree with that. Remember that the processor power of an ECU does very much for how the engine will run. That is one of the reasons why DP engineering use the VEMS ecu instead of the much better supported MegaSquirt ECU. Because of the CPU speed and extra fine resolution of loadsites.

 

Back on topic, 30% transmission loss seems a tad high. 13-16% would be more accurate.

[maxi 36 1 Cars]

Wheres Puma, im sure he would have something to say about this......

 

Maxi

[Adam B 0]

Its a bit pointless putting jon's car on to another set of rollers now though as hes not about to convert it back to standard to see what the difference on those rollers is compared to powerstation.

Its the difference between the two thats the interesting bit, not the end power result imo

 

How do we know what is a genuine horsepower anyway - they're all different sizes

Edited March 7, 2006 by Adam B

[maxi 36 1 Cars]

QUOTE(Adam B @ Mar 7 2006, 09:27 AM) <{POST_SNAPBACK}>

Its a bit pointless putting jon's car on to another set of rollers now though as hes not about to convert it back to standard to see what the difference on those rollers is compared to powerstation.

Its the difference between the two thats the interesting bit, not the end power result imo

 

How do we know what is a genuine horsepower anyway - they're all different sizes

 

Can you honestly say by putting a set of throttle bodies onto a Standard mi16 engine, its going to make 200bhp??

 

Whats to say these rollers are accurate?? In the time gap (months and months) between the two power figures they can go WAY out of calibration.

 

If there is such a biggain to be had from just bodies why run cams?? why run a modified head?? why run raised compression ratio?? why bother?? Because they dont make this sort of pwoer increase. It just dosent happen. This will become a forum myth and will lurk for ages. Everytime someone puts on a set of bodies or goes to modify an mi engine the new benchark is TB's give you 30BHP increase...... I wouldnt expect anything over 180BHP at the very very most with a std engine.

 

 

I have had this before..... Another mi at a RR meet was meant to be over 200BHp on a set of rollers back inhis area and was meant to be lightening... The bloke laughed at me so I asked him kindly to put the car on the rollers we were using that day. Same thing as on here, nobody dare argue but I always buck the trend as I cant stand bulls*it. With the car strapeed on his 200+BHP quickly depreciated into the late 170's... who was laughing at the end of it. As I have said this figure is not good for those that have had no experience of how mis react to TB's in std spec. Why do all the other struggle to even break 180BHP??

 

Maxi

[Jonmurgie 2]

Look, I'm not saying that my car definatley has 200bhp (or rather 199.2), that's just what it made on that dyno.. but what I am saying and will defend the end of time is that on my car fitting a set of 45mm Jenvey Throttle Bodies combined with BMW M3 injectors, 4 bar of fuel pressure, wasted spark ignition, MoTeC M48 ECU is gave a power increase of 30bhp (well, it was 28.8 actually) as proven by a before/after graph.

 

Your only looking like a moody argumentative tw&t with all these agressive posts... grow up!

Edited March 7, 2006 by Jonmurgie

[Dom9 2]

If an ECU and bodies give 30bhp, I'll take two please!

 

It's a good result for a standard engine... I'm sorry to say, I agree with the 'it's too good a result' brigade...

 

But, it's a definite increase and that is all that counts, so that's cool!

 

I do think one of these days we should have the rolling road shootout to end all shootouts and anyone who doesn't turn up is banned from quoting power figures!

[petert 586]

Everyone seems to say "Its the wheel figure that matters", but who's to know thats correct??

 

those who are Mechanical Engineers.

 

If it helps any, a GTi180 also makes 100kW at the wheels.

[mbayley77 0]

Well all i am seeing from this is a power hike so go drive it mate and enjoy it.

 

Oh god i am scared now. Mine is going for a rolling road tune up on friday. Not running TB's but have 45 webers and a cam which i am unsure of the lift / duration. I just want it so it will start and idle at less than 3000 RPM!

 

If it helps the engines we produce are 12000Kw but i cant see you getting an airbus on a rolling road too well.

[Jonmurgie 2]

a GTi180 also makes 100kW at the wheels.

 

Was that running a Quaife diff and sticky A048's at all?