Mike Rainbird

iTrader: (3)

Chip / Gareth / Simon,
IF you change the barometric pressure reading to achieve a specific power out put, then because peak power and peak torque are at different revs, it makes a huge difference to the peak torque reading.

GARETH T

but the power MUST change aswell,,,, been on the phone again mike?

cossiemanden

Yes the compressor can but not the turbine.
The turbine .82 trim is rated to flow 27LB/MIN at max at 2,5bar boost and 70% effiency

Mike Rainbird

iTrader: (3)

Gareth,
Of course the power changes - can't you read - I never said it didn't ? READ my statement again .

Chip

iTrader: (3)

Thats not a differential between it effective torque and BHP, it effects both the same at any given point in the rev range, its just that it effects the figures more at lower RPM, so if you make peak torque lower than you make peak bhp by a significant amount, it can effect the peak torque figure more than the peak bhp figure for that reason, perhaps that is what is confusing you mike?

GARETH T

you editing twat,,, or am i going insane again

Chip

iTrader: (3)

What makes you think it will need more than 27lb going through the turbine though?


Graph here for those who dont know what he is on about:

Mike Rainbird

iTrader: (3)

Chip,
You're misinterpretting what I am saying, but I'll try and qualify it.

Say you change the barometric pressure reading from X to Y to get the dyno to change the peak power reading from 480bhp to just over 500bhp, it has the knock on effect of changing every power reading (as you state), but more importantly, because this effects things more at lower rpm (as you state) than it does at higher rpm and because peak torque is at 5000rpm instead of the peak power of 7000rpm, the "miniscule" jump in power of a mere 20bhp, jumps the peak torque up by 50-60lb ft.

Mike Rainbird

iTrader: (3)

Gareth,
You're going insane, as you can clearly see it has not been edited .

Chip

iTrader: (3)

Barometric adjustment isnt a straight addition, like you are implying and even if it was then you would see about 21lbft at 5000rpm if you added 20bhp to the whole plot (which would be about 15lbft at 7000rpm)
So even if it worked the way you think it does, the difference at 5K and 7K would still be relatively small

RickyLee53

Just goes to show how good F1 cars really are doesn't it.

No big turbo's, no gas, no "race fuel" just n/a and they still beat the top tuners.

I'l run and hide now before somebody mentions the word torque

Mike Rainbird

iTrader: (3)

Chip,
I'm not saying you add 20bhp to the whole plot . I'm saying you make one adjustment to add 20bhp to the PEAK. This has a knock-on effect of changing every other single reading by a greater or lesser degree depending at what rpm it is, but peak torque (and quite probably the lower end power figures) are definitely changed by a greater amount than the 20bhp peak change....

Chip

iTrader: (3)

Mike, mayby harvey can show us a couple of plots with the barometric figure adjusted on his dyno, so that we can see the way it skews the whole curve?

Mike Rainbird

iTrader: (3)

I'm sure Rod will happily do this .

Cossiemaster

How come none of these mad engines are used for racing (proper racing)
Building an engine for racing is a different story than building an engine for some nugget on the road giving it a blast up a bypass.

Best use SCS.

cossiemanden

I´m NOT saying that it CAN`T be done, but am curius about how the engine produces arround 100bhp more then garret rate the turbo, on that turbine.
You have a cirten amount of flow to go thru the turbine, before the backpressure gets to high and the effiency goes way down because of the heat build up, so if he has found a way to go arround this, let us know

Mike Rainbird

iTrader: (3)

Uncalled for - Mark build's his engines for his customer's requirements .

GARETH T

what we should design is a bypass valve, that will bypass the turbine housing,,, im going to call mine a wastegate

cossiemanden

WOW, pretty quick

Chip

iTrader: (3)

EXACTLY!

Martin-Hadland

iTrader: (2)

What a trick idea

cossiemanden

So what you are saying is that if you rate a turbo for lets say 800bhp, then stik a HUGE wastegate on it and it will flow 1000bhp if the kompressor is up for it?

Chip

iTrader: (3)

Please can you explain which part of the turbo you are referring to as "rated for 800bhp" in tat question, as going back to the turbo this thread is about we have already explained to you how a GT35R is rated by garrett for the figures that have been achieved here on the compressor maps they publish.

Whatever point you are trying to make about the turbine side, you arent making it very well im afraid.

cossiemanden

Well not trying to make a point, if you reed some off my first postes, ewery where i read on the net, a gt 35 is rated to 600bhp on the .82 turbine, 670 bhp on the 1.06 turbine, and marks engine runs an .82 turbine? right?
So if garret rate there turbo`s at 600bhp with an .82 turbine, they have surely tested this?
Unless that what you are saying is that if you stick an external wastegate on it then it could easy flow 100bhp more?

RickyLee53

Not getting into the depth of this argument, just quickly want to add.
I had a sub rated at 1500wrm's i gave it 3kwrms all day long, and it didn't break. However this doesn't mean the manufacture is wrong its just i treated it better with less clip etc than the average numpty.

Anyway, maybe the turbo would do 600bhp if the rest of the engine was poor. However if the engine is very well tuned it might make 700bhp.

Its probably easier for them to rate there turbo to 600bhp and have a couple of happy customers making 700bhp on them than rating it at 700 and having 100 unhappy customers. Also if some1 has a figure in mind they might go out and buy a more expensive bigger turbo.

Chip

iTrader: (3)

Everywhere I read on the net, a YB is rated to 204bhp, and yet we all seem to manage a little more than that.

I think you are taking general statements and taking them too literally.

Garrett rate the turbo as suitable for 400-600bhp, they are NOT saying you cant get more, just that this is the range in which the turbo is particuarly comfortable for long periods of use on a wide variety of engines, it doesnt mean that it cant make a little more in a very specific case.

Mike Rainbird

iTrader: (3)

For the GT35R to be rated at only 600bhp, it would only be flowing 57lb of air?

Yet the turbo Mark is talking about (according to his figures) is rated at 63lb of air, which even being totally conservative, would make it a 630bhp turbo.

Given that the shonky T4 is generally accepted as being a 500+bhp and flows only 48lb of air, then it is acceptable to assume that the turbo Mark has, will flow enough power for 670bhp with it's 63lb of air rating?

Where do you get the 600bhp figures from - what flow rating does it give with the bhp figures?

Porkie

iTrader: (1)

PRICK

Kev's Evo with engine built by Mark, just won his class in Time Attack as a quick example.

Best use another Forum...

IMA??? hope it is and you get banned for life

cossiemanden

Well i do know this, but the actual main reason is actually that in denmark, there is a lot of different cars running gt35 turbo`s both on .82 and 1.06 trim and the max power they are getting are actually what garret state on the diff. turbine`s
An sirten Green escort had an gt-35/1.06 on it and max power was 657bhp on 98ron @ 2,4bar, later it had an gt40 on it and it was 749bhp with same size wg.
An Audi S2 did 607bhp with an gt-35/.82turbine, 659bhp with an gt-35/1.06 @ 1,9bar and 788 bhp on an gt-40.
Can name some supra`s also, but i think you get my idea.

cossiemanden

The rating`s i found at a few turbo deallers in denmark sweeden and norway, and the 600bhp is taken from an .82 turbine rating.
STILL this is NOT a dig, but curiositi about how it can be done

ECU Monitor Enthusiast

iTrader: (1)

Dont forget Autronic ecu's give 100 bhp more than any other


Sorry madettes, just friendly banter

Chip

iTrader: (3)

Very accurate mapping with a sophisticated ECU can allow more ignition advance safely, so there is an element of truth in the comment its partly down to the ecu and the mapper im sure.

Rod-Tarry

Why would I want to race my engine its in a fully trimmed road car which is used for my pleasure. Todate my MAD engines have completed 32 Topspeed runs & reached a drag final at totb, its also held the Cosworth Topspeed record for 3 years now with little sign of a challenge so please dont accuse me of not putting my car up for all to see.
By the way a MAD engine has just won TA & thats a road engine.

ECU Monitor Enthusiast

iTrader: (1)

LOL Chip,

Anything less than 10 years old now has more likely to have 16 bit
processors with floating point maths or better so will have accurate
mapping. Another topic for another day


EDIT _ What about the RP labs ecu - 8 bits, low res timer yet very capable

Chip

iTrader: (3)

You are aware they have software in them as well as hardware Im guessing, so I wont point that out............

ECU Monitor Enthusiast

iTrader: (1)

Chip, Fully aware, I do know a bit about ecu's

I editted my above post

Cossiemaster

I think you'l find saloon car racing is slightly more serious than totb and top speed runs.

Deleted by Request

Great read


Porkie...how can i be that other bloke....i never hide behind a fake name unless banned

Porkie

iTrader: (1)

Yes I am sure Mark would really struggle to build a race engine...

carlo

iTrader: (4)