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I'm making 382rwhp on 15psi out of a hypergear highflow, food for thought.

Bit unfair as you are using an aftermarket exhaust housing. The only thing stock about our turbos is the compressor housing haha.

But yeah decent hiflows should be making minimum 230rwkw.

my old slide highflow wouldnt push past 200rwkw either, @ 14psi

installed a gt3076r ball bearing internal wastegate core, .73ar avo skyline exhaust housing, ported stock nissan comp.housing, power went up to 250rwkw @ 1bar

the slide highflows are zippy turbos but dont smack down the power.

Late to come onto boost plus a low power figure - I wouldn't be happy.

Adjustable cam gears - check these first! They effect both compression and power curves. Compression a little low on only a couple of cylinders? How low? 130, 140? Compared to the good ones??

Regarding output:

Let's do some analysis here. Take 5400rpm (a nice mid-point). At 10psi you are making ~232hp. At 14psi you should make 270hp. That is IF the turbo was just as efficient and the tune was optimized for both airflows. It's not even remotely close. If it made mid-260hp at 5400rpm then that is OK.

You are increasing pressure by 16% and getting under 8% return. So you know something isn't right at least at the high boost setting. Either the turbo is too restrictive, the exhaust, intake, leaking intake pipes/intercooler (making the turbo work too hard). Or the tune is not right in AFR or timing.

I suspect a mixture of both tune and the car. For a start the higher boost setting gives a later peak power - the 10psi curve drops off earlier. This is not normal - so something isn't right there (look at mixtures and timing). If the tune was right but the turbo was out of flow then it would fall over faster with more flow.

IF you had AFRs and exhaust temps we could narrow it down further. But check those cam gears, boost leaks and drop exhaust first. There is more than one thing wrong here, but the tune can't be right until everything else is sorted first.

Edited by simpletool
my old slide highflow wouldnt push past 200rwkw either, @ 14psi

installed a gt3076r ball bearing internal wastegate core, .73ar avo skyline exhaust housing, ported stock nissan comp.housing, power went up to 250rwkw @ 1bar

the slide highflows are zippy turbos but dont smack down the power.

Here is the answer to the thread. Its the turbo. Thread closed.

All those things are inputs to how much power/torque you make. They are irrelevant once you have a dyno sheet.

Torque (lbft) = Power (hp) * (rpm/5252)

They are directly related.

i concur , my point was that i wasn't actually talking about that , my point was instead of everyone quoting peak power , why not quote torque band at whatever rpm :rofl: as IMO this explains engine characteristics more than peak power .

Power is a direct relation to torque and RPM.
but i disagree with your statement (so many variables but i cbf explaining , it was more of a joke).
You disagree with my statement on power being related to torque and RPM? Enlighten me please.
Yes what you said is right , but the amounts/values can be altered by things like air flow, ignotion timing , cam timing , amounts of fuel at whatever rpm, type of fuel bla bla bla
All those things are inputs to how much power/torque you make. They are irrelevant once you have a dyno sheet.

Torque (lbft) = Power (hp) * (rpm/5252)

They are directly related.

i concur , my point was that i wasn't actually talking about that

Sounds like some one is trying to cover their ass because they didn't understand that torque is a moment of force and therefore the factors you listed are what make up torque.

why not quote torque band at whatever rpm :rofl: as IMO this explains engine characteristics more than peak power .

What is easier, looking at a horsepower graph where power climbs as revs climb and knowing that horsepower is a relationship with torque/rpm and being able to see that the fatter the power graph the faster that car will be, or looking at a torque graph that raises quickly and falls quickly and trying to work it out? Sure if you understand the concept of torque graphs it it aint hard to work out, but even an idiot can look at two horsepower graphs and understand what is going on.

Also you are making it sound like there is no dyno graph. I agree simpyling qouting a peak power figure is a bit irrelevent unless you know more details about the setup, but in most cases people do know the details or have a dyno graph to look at so it doesn't make it irrelevent at all. If I said my car had a RB30/26 with a HKS T51R on it and on 20psi of boost it was making 240rwkw and showed you a dyno graph, would you say "meh that's irrelevant"? No you wouldn't, because you would know something must be very wrong for it to make such low power.

Edited by PM-R33
All those things are inputs to how much power/torque you make. They are irrelevant once you have a dyno sheet.

Torque (lbft) = Power (hp) * (rpm/5252)

They are directly related.

And the gearing factor too (but that's between engine and wheels regarding torque), but yeah that's it. I was so happy when I learnt that.

I kind of agree that peak power figures don't mean everything, I think power made at 2 or 3k would be a better street car figure. I've always wondered who on here has the most power at 2-3k rpm. That's beside the point though, and very different turbo etc application.

Sounds like some one is trying to cover their ass because they didn't understand that torque is a moment of force and therefore the factors you listed are what make up torque.

What is easier, looking at a horsepower graph where power climbs as revs climb and knowing that horsepower is a relationship with torque/rpm and being able to see that the fatter the power graph the faster that car will be, or looking at a torque graph that raises quickly and falls quickly and trying to work it out? Sure if you understand the concept of torque graphs it it aint hard to work out, but even an idiot can look at two horsepower graphs and understand what is going on.

Also you are making it sound like there is no dyno graph. I agree simpyling qouting a peak power figure is a bit irrelevent unless you know more details about the setup, but in most cases people do know the details or have a dyno graph to look at so it doesn't make it irrelevent at all. If I said my car had a RB30/26 with a HKS T51R on it and on 20psi of boost it was making 240rwkw and showed you a dyno graph, would you say "meh that's irrelevant"? No you wouldn't, because you would know something must be very wrong for it to make such low power.

ahh ok , what am i trying to cover my arse for? yes they are the factors that make up torque, vaguely . i've agreed with you from the start? i am talking about quoting peak power figures with no dyno sheet like a few people have in this thread? which is why i said in the first post " power is like measuring the length of your penis , torque is like measuring the girth" . read my posts properly .

Hey bud, I'd be disappointed with that figure.

I'm running the stock turbo at 12psi on my R34 with stock injectors and getting 265rwhp. If I upgraded to a high-flow I would definitely be hoping for more than the stock..

Hope you work out what it is.

Ps.. sorry to point this out but is your surname 'Maingay'? and first name Aaron.. making you A. Maingay?

Once again, sorry to point it out but I lol'd

Edited by itsme

Haha you know wat, after near 25 years of copping shit for my surname youve just come up with something new that no one has thought of. Kudos to you good sir...

Ok, so i didnt want to start any arguements for starters and everything that has been said has been helpful, bit out of my brain capacitys league but thanks none the same.

So my options are that the turbos holding back the power or that the tuners been conservative and trying to look out for my engine. I didnt get a chance to call him yesty so it'll have to wait til monday and see wat he thinks.

Unfortunately that is the only printout i recieved, so no afr's or exh temp printouts. And alls was told to me about the low compression was yeah that it was a little low on a couple of cyl's..

Oh and it does have 3" metal intake too...

Plenty of food for thought guys, thanks again :D

Will hopefully update with some answers...

And the gearing factor too (but that's between engine and wheels regarding torque), but yeah that's it. I was so happy when I learnt that.

I kind of agree that peak power figures don't mean everything, I think power made at 2 or 3k would be a better street car figure. I've always wondered who on here has the most power at 2-3k rpm. That's beside the point though, and very different turbo etc application.

ME haha i wish

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