ROLLING ROAD RESULT!!!

[blingsta]

To say im dissapointed is an understatement!!

Figures show 194.9 BHP at 5000rpm and 220.2 LB of torque at 4000rpm.. I was expecting ALOT more than that!!!!

So for all that predicted over 230 BHP on my last thread, were sooo wrong!

I mean, im happy with the way she performs on the road and all that, but i had high hopes and was expecting more than what she gave on R/R..

One of the things mentioned was that the exhaust housing on the turbo was too small and i could be losing power from that, but end result was a little dissapointing for me.. .

I am now going into hiding like a spoilt child and will dwelling on the events of this morning for many weeks/months to come.

[cliffybabe]

dude 194, whats going on???????

Was ur tyres inflated probably

[blingsta]

[Ant]

Duuuuuuuude !!!

As I said on the phone, take the positive from this, that torque figure is superb , and zero lag means your car will out accelerate most on the road

your hotside is rather small, but you knew that from the outset, the soloution is get an 0.63A/R hotside which will boost later but restrict less.

Come and drive the Tech 2 Turbo I built, that will give you an idea of the next step on the evoloution scale, its not a cheap swop though, hybrid turbos are £Â£Ã‚£ without exception.

I've not seen the dyno sheet but I guarantee the torque curve is almost flat from 2 to 5 K , and the HP climbs steeply then drops off early after the 5 K peak

Interestingly, the guy who the setup originally belonged to ( Cliff, then Buster, the Graham then yourself ) claimed 347 HP from this exact turbo setup(PBMW mag), guess he spent a LOT of time in the pub, chatting shite

given the cost ( 2.7 issues aside ) the figures still represent good HP/TQ gain for £Â£ spent, and with a lot of extra potential, the injectors, IC and ECU are all capable of over 1.5 BAR of boost , you're only @ the tip of the iceburg M8

[d6dph]

Still a good start mate, think of it as a base point and somewhere to progress from.

[jon_pure_british]

if expected 230, just imagine what 230 could feel like? :D:D:D:D:D

[march109]

To say im dissapointed is an understatement!!

Figures show 194.9 BHP at 5000rpm and 220.2 LB of torque at 4000rpm..

Dude 220.2 for Torque is awesome! Torque is what accelerates you, and legally who can drive over 70mph in the country any how? As long as your the fastest getting there!

[Demlotcrew]

To say im dissapointed is an understatement!!

Figures show 194.9 BHP at 5000rpm and 220.2 LB of torque at 4000rpm..

Dude 220.2 for Torque is awesome! Torque is what accelerates you, and legally who can drive over 70mph in the country any how? As long as your the fastest getting there!

Funny that, why does the new M5 has only 30nm more than the 550i but still leaves it for dust?

550i 5.2s 0-60 367bhp
M5 4.7s 0-60 507bhp

I cant agree that torque is what accelerates you.

Like ant said it will take time and tweaks to get you close to what your expecting.

Andrew

[blingsta]

Ive just taken a pic of the dyno sheet, who can i e-mail it to so they can post on here for me?

[Demlotcrew]

me

Andrew

[blingsta]

on way mate

[Demlotcrew]

BHP



Torque



Andrew

[Demlotcrew]

Im not an expert but it looks like there might be a breathing issue going on here.

[blingsta]

Thanx Andrew...

[Ant]

looks like exhaust backpressure is killing the top end 4 sure.

will edit and post up a dyno from mine , brb......

this is mine, 4.4 psi 0.46 hotside with 50 trim compressor.

[blingsta]

Apart from the exhaust housing, can it also be down to the standardish exhaust ive still got,? i was once told to get rid of the middle silencers to allow less back pressure.

[Ant]

Oh, the torque dip was W/spin on the rollers, the operator shat himself

[blingsta]

Ant, is that showing 220bhp and 210 lb torque?

[Demlotcrew]

214 bhp
216 lbft

Andrew

[blingsta]

4.4 psi??? and thats what you got? and mines 7.5psi

[Ant]

the peaks are shown under the graph Erel, measured and corrected HP/TQ

interesting comparison no ??

the Tech 2 is running lower CR, big turbo and a BAR of boost, will dyno that one next week, its still in having the steroe install completed, and I gotta fit he big brakes too.

[blingsta]

0.46 hotside with 50 trim compressor.

whats my compressor size again mate..? is it smaller than your 0.46?

[Turbo-Brown]

So what exhaust manifold have you got Erel?

And what's the system after that too?

I'm quite gutted for you about that mate, although are those corrected figures or at the wheel because 195bhp at the wheels is quite a lot!

[Ant]

same hotside but smaller AR comp iirc, 0.43 on yours

4 sure swopping the pipe for a 3" all the way as per Fozzys car will negate any backpressure there, cost is of course the main issue though

[Turbo-Brown]

How much did Mark's system cost to make? Seems like quite a neat solution that Jetex stuff, like Lego

Incidentally if you didn't have enough room for a 3" pipe, a pair of 2" pipes has only fractionally less X-Sectional area

[Gunni]

Can you list your complete setup ?
I´d say the exhaust back pressure is definitly the culprit there, you engine is digesting hot air above what seems to be
4500rpm, and the hot air is coming from the exhaust side, your running a way to small turbine and or exhaust, thus the crazy drop in torque above 4000rpm,
that is where the M20B25 comes on cam but the turbine and exhaust are so restrictive it doesn´t even begin to breath normally, that is actually what a ETA motor should look like at 7.5psi with a stock cam (curve and not rpms)

do not up the boost one bit infact you should lower it, do you have a EGT gauge in there?

You should get a bigger turbine and bigger exhaust, results at 7.5 will sky rocket !!

[Ant]

parts were £150 ish iirc, labour was 8 hours or so( me and mark for 4 hours each )

worst part, as always is getting the pipes past the steering 3" is big when you've got 2" to fit it into

[Turbo-Brown]

That's a pretty good price for that much pipe and a big silencer, and a day to assemble it is pretty good going too.

The path is clear!

[jkarran]

I cant agree that torque is what accelerates you.

It is the torque that accelerates you (or more correctly, the linear force applied to the road at the tyre contact patch as a result of the engine torque multiplied through the gearbox).

The difference in 0-60 for the M5 and 550 you quoted is actually quite small. Is the 550 an auto? Does the M5 need a gearchange in the 0-60 dash?

The area under the torque curve has a direct impact (besides gear ratio) on the speed of acceleration through a gear especially at low road speed.

jk

[Gunni]

I cant agree that torque is what accelerates you.

It is the torque that accelerates you (or more correctly, the linear force applied to the road at the tyre contact patch as a result of the engine torque multiplied through the gearbox).

The difference in 0-60 for the M5 and 550 you quoted is actually quite small. Is the 550 an auto? Does the M5 need a gearchange in the 0-60 dash?

The area under the torque curve has a direct impact (besides gear ratio) on the speed of acceleration through a gear especially at low road speed.

jk

you are incorrect, and fighting about it can become a very lengthy discussion

[Morat]

well, I'll agree that the arguments about this are long (and painful).
But torque is where its at.

All blingsta needs to do is hold that torque higher up the revs and he'll have an impressive power figure!

[Dan318-is]

well, I'll agree that the arguments about this are long (and painful).
But torque is where its at.

All blingsta needs to do is hold that torque higher up the revs and he'll have an impressive power figure!

so why do f1 cars have 900 bhp and about 250 lb ft of torque?

you need both power and torque for a well performing engine

[d6dph]

Oh, the torque dip was W/spin on the rollers, the operator shat himself

He looked a little puzzled, Maybe we should have warned him

[Morat]

well, I'll agree that the arguments about this are long (and painful).
But torque is where its at.

All blingsta needs to do is hold that torque higher up the revs and he'll have an impressive power figure!

so why do f1 cars have 900 bhp and about 250 lb ft of torque?

you need both power and torque for a well performing engine

Because they rev out to 20k. Power = torque x revs
If they could add another 20 lb ft they'd have even more power up there.
I'm not saying power isn't important. Its just that people get obsessed by the power output and disregard the torque.

[Gunni]

not both , you just need your engine to stay within the maximum possible region of the max hp figure,

if you had a 10gear SMG transmission your powerband could be ridiciously narrow but still accelarate like a thunder,