Useless comparing wheel figures from Mahaa and Dyno Dynamics rollers , what would be far more interesting would be to see someone elses Powerstation graph from a car with similar power...

 

thats one impresive list of mods you got there pal

 

very good point

 

One car , same map , same mods all within a week or so...

 

Martyn - how did that car do on an Ecutek Delta Dash run ?

 

Sorry m8 , runs SimTek so no way of knowing..

 

Dynos..............here we go again

 

lol , just wanted to show that the transmission losses on the Mahaa can be as high as 160bhp+ but the flywheel figures are quite similar...

 

For some of the dyno ignorant among you MAHA RR are geared towards flywheel calculations, not whp. Anyone who compares DD and MAHA wheel figures is a plank.

I have tested my car on DD, MAHA and hub dyno's over the past three years.

My car was also tested on a hub dyno (which the graph is in the articles for all to see) and attained 440bhp / 470lbft at the HUBS. Using the hub to flywheel calculator on AET's website (which is where I had the run done) equates to a flywheel figure of 534bhp. Not too different from PowerStations 530bhp. Even based on the lowest transmission calculation I have been informed of by another source, it still equates to over 500bhp at the fly. Remember this is on pump fuel (I have NEVER run any form of additives in this new engine), with a standard position turbo and only running 1.7bar peak boost.

Just so you are aware, PowerStation have problems running my car on their rollers without slip, it requires double strapping. The only other Subaru that has caused this on their rollers, has been their Type25 Race Car.

Prior to Richard Bulmer fitting and mapping the Hydra, he also doubted my car was running 500+ (based on how the car performed on the 1/4m). He was humble enough to admit the error of his initial opinion after he actually drove the car, whilst he had it for mapping.

Regardless of what ANY RR says, the only way of proving to some of you will be with a respectable 1/4m time. Hopefully that will be a reality in the near future, with me driving or by hiring a STIG.

For the pain that it causes me to agree, I do agree with what Mark has just said. I'm over the dyno thing now and just need to try and ensure the car actually performs as it should on the black stuff.

 

Which makes a mockery of the WHP figures.

Given the choice, I'll have the Hoffmann 429WHP over the MAHA 302WHP any day, because I know that the car will be much quicker with an extra 127WHP !

WOW, that's over 40% more

 

Martyn,
As a matter of interest, i'm sure you have built a few tall Cosworth engines and if so, how have you found (if any) the differences in power between the same turbo on a non Cosworth built 2.5 (i.e. with standard heads and cams)?

 

Mark,
No one should compare the ATW figures on a MAHA against an other. It is a waste of time, and it is the flywheel figures that to be taken in to account (regardless of peoples view on calculation methods). Either that or they are all wildly wrong, which means we are ALL in the same boat!

 

Shaun,


Please can you ask the powers that be, to add a "TONGUE IN CHEEK" smiley.......................


And NO, that's not as bad as you, and Duncan having a "semi side by side"

 

It is weird really, I have used MAHA and agree with Shaun, hence my taking the mickey of the whp. It showed a huge loss for me but in reality was just a figure... it might have said FHP (fictional horse power). Ultimately the Flywheel figure was pretty accurate or certainly as accurate as any of the others.

In recent weeks I have been on Dastek and Dyno Dynamics rollers with the same car, same tune and the recorded flywheel figures of 0.7 bhp different, whilst whp figures were vastly different. Therefore I deduce that the flywheel figures that should be compared to show a true comparison.

Comparing different cars on different days on different dynos though is very troublesome. Good job all the 2.5 big guns will be shooting it out at Zen next month to get the fairest comparison of components, turbos and tunes.

I hope you can make it Shaun - the bacon butties will be superb if nothing else to Liz

 

We have Shaun , (building 2 more in the coming weeks with GT35/42 turbos) although unfortunately to such a spec as to be unable to compare them properly ...
The best I can offer is that an STi4 (stock heads and cams but chambered to suit the 2.5 piston) with a GT35R in comparison reqd 1.8 bar boost to acheive roughly the same power figure as the Cosworth engine @ 1.4 bar on the same turbo...
There was of course a massive torque difference in reverse ..
Will know more later this week when the Cosworth engine gets mapped for 20% Meth and 1.8 bar...

Shaun , I can understand where you could be getting such good figures from though , the heads are a big part of it..
We have seen some massive gains as a result of doing the heads on Subarus , all whilst retaining the stock cams so more to do with the midrange than anything else..

 

I love these threads....

 

Martyn,
Thanks for the feedback. Certainly the answer I anticipated.

 

Recognise those graphs........

 

Would that go for 2.0 litre subarus as well ?

What sort of headwork seems to work the best ?

TIA

 

Fantastic thread!
I am very interested in this for future development of my Forester sti,
I currently have her on am AFP TD05 20g running 380bhp@6900 and 408lb/ft @3100, @ 1.5bar, It has an EJ255 (slightly higher compression then ej257)
At some stage I would love to get a forged motor and big turbo as is described at the start of this thread, I am a bit disheartened to see that no one seems to bo making much power before 4000rpm
Is that just what you have to axcept if you want 470-480bhp??
Is anyone using the MD555 with the ciramic coated turbine housing??
Thanks
Dan

 

It depends on what you call not much power before 4000 rpm. I think Shaun's latest graphs will make you think otherwise (as will mine).

 

Dan,


Couple of things. Some of the graphs are of 2.0lt cars, just to show comparisons between dyno's, and dyno runs will always show later spool up than normally achieved on the road.

A turbo such as the MD321T can achieve circa 1.5bar by 3000rpm on non VVT heads, and I think Andy Forrest gets circa 1.5bar by 2400rpm on his 2.5lt with VVT heads.


Mark.

 

Dan,
I have been trying to find that magic forumulae over the past year or so.... I have now found it.

It is all still in progress, but using a new spec. AET turbo on Hydra management, the response is awesome.

How does 480ftlb @ 3500rpm grab you!

As I said, this is all "work in progress" and we hope to get more out of this turbo, but we are currently at 500/525 on VPower.

You can now have your cake (with supporting mods) and eat it.

 

Awesome result. But that means you could change up at 4200rpms and still be in good shape, should suit your driving style well then

 

What you trying to say about my driving style!

 

i met two guys both running the md555 at the surrey rolling road last week. one had it on a 2.5 and managed 411bhp and the other had it on a 2.35 and only managed 453bhp.both had simtecks, built up blocks with full supporting mods.

 

Thats not fair!!


He will of changed gear long before that

 

one had a built ej257 and the other a relinered 2.33.
There's more to that story

 

I have an MD555 on trial at the moment, aswell as a Blouch Dominator 4 and a T38 Turbo Technics hybrid.
We will be fitting the 555 and the Blouch to built 2.5's and the T38 to my own 2.1 Stroker.
I will be posting all the results when they are ran in and mapped.

 

i know what you mean i was with another scoobynet member magic seven who was also suprised. both had newage cars one was a hawkeye the other was a wagon very nice motors. they were expecting around the 500s they warent very happy with the result they got from the md 555. i had never heard of the turbo before so i didnt know what it would produce...