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:rofl:

f*kn lolwat????

. Since the car still use factory drain trans, for road use and city driving, it won't be too comfortable.

i reckon it'll be alright ...maybe not ideal but good enough... mines a little doughy around town but its all worth it when sink the boot into it :D

Whilst I agree with you Stao, if you make the assumption that the turbo is well matched (and you'd be the one to tell us how well matched the front and rear of this particular turbo is, given that we're talking about an SS2, not a 3076 here), then if you plot your operating point off the top end of the compressor map then you'd have to think that you were also pushing the turbine side too hard.

The real question here is whether that operating point on the 3076 map is equally as bad on the SS2 compressor.. Actually, it's not. I still agree with you. The real question is whether the SS2's turbine side is too small, but I thought I'd point out that we're looking at an orange map when we're talking about an apple compressor.

Fair point GTSboy

Would have been ideal to use a ss2 compressor map and I actually asked for the ss2 compressor map, but as there wasn't one Stao said to use the Gt3076 compressor map

You're a compressed apple.

Haha :w00t:

  • Like 1

Well, if using the 3076 comp map was Stao's idea then obviously he reckons the SS2 compressor will have at least a broadly similar map. Doesn't say anything about the turbine side, but that's life.

And that actually brings up an interesting point. To create a compressor map for a given wheel is a lot of work. There is a metric shit-ton of information in a compressor map. You have to run the compressor at a particular shaft speed and vary the restriction on the compressor outlet whilst measuring the flow going through it very accurately, measure the temperature change of the air and the shaft speed, then do some calculations on some of that data to get the efficiency, just so you can plot a single point on the map. You have to do a whole lot of this at different shaft speeds and restrictions to flesh out the map, then joint your dots up in the appropriate lines and "circles" to create the map. This is within the means of your Garretts and your Borg Warners, but it is probably outside the means of nearly every smaller turbo manufacturer. Just doing it for one compressor is a lot of work, but if you've got 10 or 15 compressors on your catalogue, setting out to map them all would be a daunting task.

Well, if using the 3076 comp map was Stao's idea then obviously he reckons the SS2 compressor will have at least a broadly similar map. Doesn't say anything about the turbine side, but that's life.

A 90T 60mm GT30 turbine is a reasonable comparison.

Us Vic guys even bring out the Cadbury favorites at these functions

I'll do this when you get rid of the Merc and get back into Jap cars :P

That's not gonna happen anytime soon

......Ummmm, cant say I totally aggree with you there hypergear....

A compressor map is made up of the efficiency islands based on a range of factors... one being shaft speed!

As whilst I agree its probably not the most accurate way to tell, it is very evident that blah_blahs engine has already gone over the maximum "efficient" shaft speed of 145,000rpm...

What causes the shaft to rotate? The turbine wheel!

Another interesting fact I learnt today talking to the right people:

An inefficient engine will run a higher timing advance to allow the extra time required to burn the a/f....

The more efficient the engine the less timing it will require with no power loss...

Are you talking about flow or volume?

Volume can be measured the same way a chamber is checked...

But once you've been doing this for over 10years you start to get the hang of it...

Where as many people thrive to get perfect port volumes, the fact of the matter is there is a lot more other important things to consider, as a few cc difference in a port is not going to tarnish a whole engines performance.

Im an odd type of guy...

Many years ago, back when we used flow benches, we were building a race engine, target power was just over 600hp....

Selected aftermarket heads for it, to which we copped a lot of criticism for as "they won't be big enough"

Done our port work to it, and got them flowed...

People litrally laughed at the results and mocked us...

Went ahead and bolted the heads on, and sent it to the engine dyno...

650hp...

So why would I choose to use a flow bench again?

So that was one engine....how do you know you havent gone backwards with others, or if the port is really noisy and turbulent

I dont really care for flow bench results, was just intrested to see what your RB results were

so dont take what im saying as critisism merely intrested

Why? So you can see how close you are to making the flow strip off the short turn. Or how about using a velocity probe to make sure you've got the cross sections right? Or see how well the flow is balanced around the periphery of the valve? Or seeing if the changes you make work better at low lift than high (or vice versa), or if you need to consider a different valve seat shape? etc etc etc.

Edited by GTSBoy

bit off topic but I read an interesting way to make a home flow bench using an afm and a vacumn the other day...

I'm sure you can figure the rest out but I thought it was rather clever...

Let me ask this...

Do you even know what your talking about?

The fact that you are using big technical words only tells me you have no idea what you are talking about so you are just trying to confuse everyone...

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