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I tried explaining that, unfortunately the cooler was blamed for the IAT too which is pretty funny. :P

I think he realised it was the compressor that was causing the heat, hence the new turbo that was trialled.

It's way too scientific for anyone to bother but you could calculate intercooler efficiency if you measure MAP and temperature on both sides of the cooler. You can easily calculate what the temperature should be on the cold side purely based on pressure drop. The difference between that figure and the actual temperature on the cold side is due to frictional losses. You have to be sure you're measuring steady state condition and that you equalise the airflow cooling the cooler (ie dyno fan) in a fair manner.

Example, if you drop 22psi to 19psi through a cooler and your hot side is at 60 degrees, a 100% efficient intercooler would drop the temperature to 33 degrees. If you only drop the temperature to 40 degrees then your intercooler is 73% efficient. The efficiency loss is friction causing pressure drop. I knocked up a quick excel sheet to fiddle around (you need absolute MAP and absolute temperature, for a start...). It's possible I've overlooked something, my maths is a bit rusty :P

Of course, it's easier for most people to slap another cooler on and do another dyno run. Or if you run a turbo workshop you throw a different turbo in there :)

Actually, on the late run the IT stayed at about 45 degrees which wasn't too bad. But the pressure drop was still there. I think they've packed way too much fins inside their coolers. But if you are stuck with this cooler and prefer not to have it changed, all you have to do is drill a 1inch whole on both sides of the cooler pippings and bridge them together. That way it should carry 30% of extra flow, except its not been cooled of course.

The ATR45 AKA ATR43G4 SAT turbocharger is now released on our site for both Rb25det and Rb26det single turbo setups. They are $900 each to build.

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I'm working on the internal gate version of that currently. Reaching 350rwkws on pump as a bolt on turbo will be awsome

It's way too scientific for anyone to bother but you could calculate intercooler efficiency if you measure MAP and temperature on both sides of the cooler. You can easily calculate what the temperature should be on the cold side purely based on pressure drop. The difference between that figure and the actual temperature on the cold side is due to frictional losses. You have to be sure you're measuring steady state condition and that you equalise the airflow cooling the cooler (ie dyno fan) in a fair manner.

Example, if you drop 22psi to 19psi through a cooler and your hot side is at 60 degrees, a 100% efficient intercooler would drop the temperature to 33 degrees. If you only drop the temperature to 40 degrees then your intercooler is 73% efficient. The efficiency loss is friction causing pressure drop. I knocked up a quick excel sheet to fiddle around (you need absolute MAP and absolute temperature, for a start...). It's possible I've overlooked something, my maths is a bit rusty :P

Um, saywhatnow? I bolded the bit I'm most interested/worried about here. Are you saying that the ~27°C temperature drop you predict there is due to the 4psi pressure decrease? Because if you are, then I would disagree.

If you're saying something about the efficiency of the intercooler, with no mention of the temperature or velocity of the air flowing across the outside, then how can you even start to calculate the temperature drop of the air inside? I'm just not sure I follow your statement at all.

Edited by GTSBoy

There's no way the blitz cooler puts a hard limit of 250rwkw, no matter what the calculations say though. Designing turbos around intercooler efficiency seems a little weird when surely it can't be the problem.

No, my setup isn't the same as Stao's, but the setup from the turbine outlet to the throttle body IS the same (stock piping, too).

And if I can get 400rwkw at 21psi on a GTX3076.... the intercooler cannot be the issue man.

Wasn't there a change in the long side pipe diameter with the later version of the Blitz return flow kit ?

I'm not sure if it makes any difference but there does seem to be inconstant results with these IC kits .

Also that above mentioned Hypergear turbo looks interesting , are we allowed to know how its wheel diametres differe from a GT3076R ?

Cheers A .

Air temperature / velocity / pressure are all linked together in neat proportional formulas.

Just by looking at pressure drop without having the density (temperature) wont get you very far.

That's why MAP sensors always need the air temperature to calculate actual air mass.

I'm not saying the Blitz Return Flow Cooler is ideal, but it looks pretty well engineered,

The new turbo is a little bit different. It is using the steam peddle turbine system that we've been working on since the start of the year. In comparison of earlier models, the approach method of engine's dynamic discharge is more direct. This turns the negative effects of the restrictive factory engineered log manifolds with bottle necks effect positive. Since the swirl is reduced, hot air moves in and out of the turbine side at a faster rate, this makes the use of over sized compressor wheel less likely to chock an engine, this also makes turbo response less sensitive to compressor change as earlier results indicated.

This turbo can provide performance of a larger turbo while retain response of a smaller turbo, it does not necessarily relay on externally gated system to make power, and the most important of all, it is simple and cost effective to build.

That is the perfect name for that sort of a turbine system. Sure PM for details.

Dummy up the bolton version this weekend. I'm had some new actuator brackets locally made, that will mount the actuators above the comp housing instead of on side. That will not only keep the actuation angle straight, but will also making life much easier on installation:

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I have 64mm comp billet wheels, Those are from ATR28SS15. It peeked 281rwkws, and averaging about 275rwkws pump 98 fuel, on my SR. On dyno it is slightly more responsive then a 2871 while made more power.

ATR28SS15

Does the ATR28SS15 have the same turbine as the ART28SS-2 ?

If so then that sounds like what i want with 64mm comp wheel

Is it a 9 blade rear wheel or 11 ?

And can the GTR housing be made to fit to it ?

Um, saywhatnow? I bolded the bit I'm most interested/worried about here. Are you saying that the ~27°C temperature drop you predict there is due to the 4psi pressure decrease? Because if you are, then I would disagree.

If you're saying something about the efficiency of the intercooler, with no mention of the temperature or velocity of the air flowing across the outside, then how can you even start to calculate the temperature drop of the air inside? I'm just not sure I follow your statement at all.

Yeah I feel like I'm missing something as well. I'm not sure if it's fair to compare pressures and temperatures like that in a dynamic system using gas laws that are derived using a constant volume of gas. I initially thought that since the volume flow was the same on both sides that you could simply compare pressures and temperatures. But volume flow isn't the same thing as volume. In saying that though, what we really care about is the delta-T, and pressure drop. The most efficient cooler will have the biggest delta-T and smallest pressure drop, all other factors being unchanged. So your metric could simply be delta-T divided by delta-P, the higher the number the better.

The air flow across the outside is absolutely important, and changes will show up as a difference in cooled charge temperature. No flow means no cooling and 0% efficiency, you will reach an upper bound of diminishing returns depending on the design of the cooler so the main thing is to be consistent with cooling air when comparing cores.

OK, Stao, I will be making a purchase from you late this week. However I'm still not 100% which turbo. I was going to go the SS2 however I'm going to shoot higher. The car is only a toy so I don't care if driveability suffers. I'm thinking the G3. That would net a comfortable 300+rwkw on pump and 350 on e85, correct? I've just picked up some ID1000s to go into it along with a walbro460. Will be sourcing a new clutch this week after which I'll be ready to go.

I get so confused about which turbo does what!

I will be dynoing the ATR43G4-SAT model on Thursday. Thats is a very good turbo if you are looking for a high powered bolton unit. One thing is you might have to run about 23psi, which is no problem for a Neo motor.

anyone run any of the hiflows with 3" metal intake to stock airbox? if so what are your results?

i would like to avoid running pod filter if possible due to noise and wanting to keep engine bay standard looking.

anyone run any of the hiflows with 3" metal intake to stock airbox? if so what are your results?

i would like to avoid running pod filter if possible due to noise and wanting to keep engine bay standard looking.

You will not have a problem as long as metal intake its fine airbox will do 300 plus no prob

anyone run any of the hiflows with 3" metal intake to stock airbox? if so what are your results?

i would like to avoid running pod filter if possible due to noise and wanting to keep engine bay standard looking.

No problem with my 80mm intakes up to 400kw on e85. A stock looking bay is a priority these days.

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