^^^^ All good questions. Since Mr. Buschur was kind enough to share this data, and already stated that the customer has ordered a BR Race FMIC, then what I'd like to see is him take the next step and show a before and after on the same day showing a re-run of the Perrin and then another run immediately after the BR Race core is installed. Assuming they leave the bumper off, then it should be easy to do within 15-20 minutes from 1 run to the next, so conditions should be nearly identical, and easy to see how they compare.

 

!st thing, is it 100 percent a Perrin FMIC? anything can be rebaged IE: buy it of EBay (not knowing what to look for) and just being told "ya its a perrin"....It could happen

 

whats up dave, you know im deff coming back.

Teal2nr....well it was ordered straight from perrinperformance.com

 

K fair enough, just curious

 

He already said he ordered it directly from Perrin, but also "Perrin" is literally molded into their cast end tanks, so I highly doubt anyone is taking the time to copy their intercooler when they could make an AMS, ETS, etc. copy a lot easier.

 

^^ holy god I know, jebus....there are such things knock off parts (not in this case)...Its not a knock off I KNOW! god damn.

 

I appreciate the response. Couple of things though.

First the water/alky injection nozzle had nothing to do with the IAT's being higher/lower. The sensor was mounted low just after the intercooler, the nozzle for the injection was mounted up nearer to the throttle body.

The only other thing I have to say, since I am not argueing or bad mouthing anyone, a 38-54 degree increase in air temps on a single gear pull is absolutely not acceptable to me. It is actually rediculously high.

Oh hell, one other thing, the RPM of the engine doesn't determine the efficiency of a turbocharger.

 

Haha. OK. I believe you.

 

This is my car out on the street this past weekend. It was pretty hot here....90 degrees or so.

This log shows a 2nd, 3rd and partial 4th gear pull. Peak boost almost hit 40psi on a HTA3586 and a Buschur Race FMIC.

From 40 to 100MPH, my IAT's gained 3.6 degrees F. Now that's efficiency!!

 

Wow, thanks for posting that Slorice, THOSE are MORE than acceptable IAT's and how I want and need a FMIC to work.

BTW, I'm assuming it's all straightened out now..........so how's the GTR race work out?!

 

Combined with engine VE and boost pressure, it will determine your pressure ratio and airflow rate. Unless engine VE is dropping like a rock and the airflow demand remains constant, RPM will change your turbo efficiency. Reving higher will also produce more heat that has to be transferred to ambient.

I will say though, I’ve never seen IATs as good as what you often post and I have numerous friends running the exact same core you run. 30-40F increases on a drag pass are completely normal on 35+ PSI on those cars.

But we also have thinner, hotter, and drier air that transfers heat less effectively and produces a higher pressure ratio at a given boost level.

 

-That makes complete sense on the WI not being an issue at all. Check!

What kind of air temp sensor do you normally use and what kind was installed on this car? What i see on cars that have air temp sensors pre and post IC, is that they take a while to react.

For instance. At 30psi and say 4500RPM, the turbo is going to be pumping out 350degree air, and with our IC being about 82% efficient, the temp coming out of the IC is going to be about 130F. This is something you can even calculate. But i bet your air temp sensor is seeing much lower than this because its still "warming up".

I am not trying to make a big stink here, but that is completely wrong. The temps go up as RPM goes up in most cases because you are pushing past the compressors efficiency. And now with your head and cam package you may be pushing way past it!

Lets take a GT358R running 3 bar absolute. Now look at a compressor map for this turbo.



Lets say at 4500 RPM you are hitting 30psi of boost and the compressor is in the the 72% efficiency range. The turbo outlet temps are in the 350F range, and with our IC being about 82% efficient, the temp coming out of the IC is going to be about 130F.

Now look at how around 7000RPM the turbo is more efficient (78%) the outlet temps go down (339F) as well as the temps out of the IC (127F). Which i bet is very close to your peak power RPM.

But above this point the turbo get less and less effecient very quickly. At 8500 the turbo is in the 66% effeciency range the air coming out of it is about 390F and the temp coming out of the IC is going to be close to 140F.

All that to say that temps go up, and given the potential, slow reacting nature of the sensor, could explain this.

What i see is the same 30-40 degree change on the dyno where you dont' have quite the same airflow as on the track. And while you can calculate that the change may only be 10-15F its the sensors slowing reacting.

Now in defense or DB and their tuning, which is very well known and known to be top notch, maybe there is something else going on. Meaning while his temp readings could be wrong or not fast acting enough, its probably consistent from car to car. And now something is different with this car. Its possible that since this customer is in an area where the roads are salted and there is more corrosion going on from the winter, its possible that the FMIC is really corroded! I have seen some of our old raw cores come back fuzzy from this. Maybe this is the case here, which would really mess up the efficiency of the core.

Or maybe the IC is full of oil from too much blow by or bad turbo?? I would assume these things were check when the old FMIC came off for the new one.

 

Yup, everything seems good to go. I'm going to pull the pumps out in a couple weeks I think to see what the filters look like. Its running pretty rich right now....high 10's. Might need to mess with the IAT fuel correction map a little as it was pretty cool last week when you fine tuned it compared to now.


GTR wimped out but going to keep on him to see if he'll give in. Could be a pretty lucrative opportunity for me.

Thanks again!!

 

I'm not trying to take sides Jeff. But take a look at the data log I posted. It has ~5 seconds of data after the pull and the IAT's don't go up. In fact, pretty much right after I let off the gas in 4th gear, the IAT's go back down to "ambient" temperature.

The sampling rate of modern day sensors is pretty quick, so I don't think this is a valid argument.

 

First, this car and I believe just about every car I've ever tuned use the same air temp sensor, the GM/AEM IAT sensor. So the data is atleast comparable and consistent from car to car. Then I'll move onto the end, the intercooler is clean as it's never had the vents hooked into it, car is smoke free, spools correctly and has no power issues, so I'd put money on the turbo being 100%. The FMIC has not been run in the winter, it is new.

As for the engine rpm having nothing to do with, the statement I made, of course depending on boost levels the RPM of the engine will make a difference. What should have been said was turbo shaft RPM on your end instead which is more correct.

Breaking down the compressor chart like you did with RPM written on it is, at best, a guess where the car is running in the map. VE of the engine, boost pressure etc. will change where it actually is.

I think what I've concluded from this is the FMIC was getting much hotter and the AIT's that I was seeing is acceptable to Perrin. I'm still baffled as to why they were so hot as it's not even in the ball park of acceptable to me and I sure seem to recall the last time I ran one of these FMIC's it was much better than this.

The customer is swapping IC's and will be back....I'll try to remember to post data from the swap when it happens.

Anyway, just data and still great gains in power on this car from a few parts that were swapped.