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Just to add a bit of fuel to the fire! I had a bit of time up my sleave and was bored so I made up this graph. Now it's not perfect, there are different dynos, different boost levels, different correction methods etc etc but it gives a decent indication of levels of response and overall power on stock stroke rb26's.

Green Line - 2.6L Garrett T04Z 0.84 (24psi) on modded china manifold, HKS 272 10.25 cams and decent head porting

Yellow Line - 2.6L Garrett T04Z 0.84 Split (24psi) on 6-boost split manifold, JUN 272 10.5 cams and no head work

Black Line - 2.6L Garrett 3582R 0.8x T4 rear (28psi) on china manifold, TOMEI 270 10.8mm cams and no head work

Blue Line - 2.6L (the motor from the yellow line) but with Garrett 2860-5’s (24psi) on 6-boost low mount manifolds

Pink Line - 2.6L with HKS GT-SS (18psi) on Tomei manifolds with Tomei 260 9.15 cams with head porting

Anyways a picture tells a 1000 words (sorry about my shocking excel skills)

fndagj.jpg

Edited by Cerbera
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Just to add a bit of fuel to the fire! I had a bit of time up my sleave and was bored so I made up this graph. Now it's not perfect, there are different dynos, different boost levels, different correction methods etc etc but it gives a decent indication of levels of response and overall power on stock stroke rb26's.

Green Line - 2.6L Garrett T04Z 0.84 (24psi) on modded china manifold, HKS 272 10.25 cams and decent head porting

Yellow Line - 2.6L Garrett T04Z 0.84 Split (24psi) on 6-boost split manifold, JUN 272 10.5 cams and no head work

Black Line - 2.6L Garrett 3582R 0.8x T4 rear (28psi) on china manifold, TOMEI 270 10.8mm cams and no head work

Blue Line - 2.6L (the motor from the yellow line) but with Garrett 2860-5’s (24psi) on 6-boost low mount manifolds

Pink Line - 2.6L with HKS GT-SS (18psi) on Tomei manifolds with Tomei 260 9.15 cams with head porting

Anyways a picture tells a 1000 words (sorry about my shocking excel skills)

fndagj.jpg

I'm not trying to discredit what your trying to do - but different dynos, different days, different strapping methods, different setup methods, possibly different rolling diameters, different drive ratios, different tunes, different cam timing, different ramp rates, different tyre temps - the list is endless!!!

I can tell you from expereince that on a Dyno dynamics dyno that even getting consistant runs from day to day with no modifications performed is a task in it self. I usually get within +/-2.5% of the previous runs with the methods we employ with no changes. You need to get all these cars on the same dyno within 2hours of each other for real comparison. I would get the tacho numbers precisely calibrated so you can compare in rpm not vehicle speed.

I'm not trying to discredit what your trying to do - but different dynos, different days, different strapping methods, different setup methods, possibly different rolling diameters, different drive ratios, different tunes, different cam timing, different ramp rates, different tyre temps - the list is endless!!!

Dude, everyone knows that (it was only a matter of time before someone jumped on it), it is just a rough comparison for people to see, we are on a forum not in a laboratory.

Keep the comparisons going, can you put "twoogle" on there, I am sure Paul won't mind.

Mike

Dude, everyone knows that (it was only a matter of time before someone jumped on it), it is just a rough comparison for people to see, we are on a forum not in a laboratory.

Keep the comparisons going, can you put "twoogle" on there, I am sure Paul won't mind.

Mike

I just dont see the point in comparing when for example there could be the difference between the 35R run on a happy dyno when compared to a TO4Z strapped tightly on a low dyno and they both read the same power now is that to say that the 35R is the same size as the TO4Z???

Thats why I hate these threads becasue the results are arbitary!!!

Now it's not perfect, there are different dynos, different boost levels, different correction methods etc etc but it gives a decent indication of levels of response and overall power on stock stroke rb26's.
I'm not trying to discredit what your trying to do - but different dynos, different days, different strapping methods, different setup methods, possibly different rolling diameters, different drive ratios, different tunes, different cam timing, different ramp rates, different tyre temps - the list is endless!!!

i said pretty much exactly the same thing in the original post... i have accounted for a few things you have listed though

I would get the tacho numbers precisely calibrated so you can compare in rpm not vehicle speed.

tacho numbers are directly proportional to rpm... this graph actually translates 2 graphs from rpm to road speed, i can repost it in rpm if you like!!!

Edited by Cerbera
Dude, everyone knows that (it was only a matter of time before someone jumped on it), it is just a rough comparison for people to see, we are on a forum not in a laboratory.

Keep the comparisons going, can you put "twoogle" on there, I am sure Paul won't mind.

Mike

i cant find a twoogle graph in rpm and the ones based on road speed seem to be in 3rd gear (he has a os mission so i dont know the road speed/rpm relationship)

i said pretty much exactly the same thing in the original post... i have accounted for a few things you have listed though

tacho numbers are directly proportional to rpm... this graph actually translates 2 graphs from rpm to road speed, i can repost it in rpm if you like!!!

Yes but different cars may have different diff gears and tyre rolling diameter so while 4th gear is usually 1:1 the rpm/rev ratio may be different car to car.

What is the purpose of this thread??? Are you comparing turbos or engine setups or what?

all 3 cars done by road speed were r32 gtr's with 1:1 4th gear ratios, 4.11 diff gears and very similar rolling diameters (2 exactly the same) the other 2 cars were on rpm... i know the rpm relationship between speed and rpm in the r32 gtr's so i can translate from there...

turbos comparison mainly, most the motors have very similar specs

Edited by Cerbera

post-40430-1249045397_thumb.jpg

the red line i added is a rb27 with t04z on 22psi and pump fuel and only revved out to 6800rpm roughly on that run (misfiring above that so we called it quits), usual redline is 9000-9500rpm. This dyno reads very low too compared to some of those numbers on there :angry:

Edited by unique1

looking at the graph however inaccurate it may be the yellow line twin scroll t04z setup looks the bees knees compared to the others. same response as the 2860's and loads more top end.

I still can't decide what turbo choice to go for with my new build. 26/30 twins or twin scroll is the question ;) response is the main goal but i wouldn't mind getting 350kw+ i was origionally thinking of slapping some ss's on there. be nice to have the cash and your own dyno to change them all over and pick :happy:

Edited by GT-RZ

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