Twin turbo TR Dyno

[I myself have some issues with norwood's work. I can't understand why that turbo 348 car is running around with only ONE weak little Bosch compressor bypass valve. Those are only good for moving 200 hp worth of air. And he is trying to vent of twice as much through it. I am sure that is a huge limitation; and am willing to bet that it has, at the very least, a torn seal. But to pay for that kind of a job and get a $30 bov, just seems silly to me.

But I dont post threads to make fun of Norwood's projects. I dont make fun of people's car. ALthough Diablo SV are for girls ..... ( jk ). I just thought he should know he looks like a complete donkey.[/QUOTE]

I'm sorry, I thought I had already responded to this issue; it's come up before. The visible turbine relief valve you see in the engine pic is only venting from the intercooler. There are two additional wastegates; one for each turbo.
If I've omitted this; my fault.

 

348 Turbo - Do you have a bigger pic of your engine posted somehwere? Looks great!

 

No, sorry; I read it the first time. There should be two wastegates. Well that would be the easier way of piping it. But the CBV/BOV is not a wastegate. It diverts air from the compressor wheel when the motor wants to go back to vacuum. ( like between shifts ).

Wastegates divert exhaust gasses from the turbine.

 

Totally untrue! I used a small T3 (55 trim) on my tiny 2.2L engine and made over 300 whp with it and that was paired to a pathetic standard T3 turbine in a small 0.48 A/R housing. The largest T3 compressor (the Super 60) can move even more air. I have a few pals running 11's on those compressors.

 

Wow, i'd really like to see that.

http://www.turbofast.com.au/img/t3-50.JPG

I can't find a 55 trim, dont remember hearing of one. Best possible senario, the 60 trim will pump 36lbs or air/minute.

and you weren't on the bottle too?

 

Ive thought about this for a few years while trying various turbos on my cars, so I am fairly well prepared to answer your question. Please take what I say as just my thoughts/results as I have no intentions of sounding like a know it all, or trying to stir the pot!

There are three basic efficiencies one can look at improving to gain power.

1) Compressor efficiency
2) Intercooler effciency
3) Head efficiency (aka "VE" or volumetric efficiency)

Now, start looking at how a certain percentage efficiency gain in any of those areas effects power produced.

In my case, I am used to small 2.2L 4 cylinders. So, lets assume a 2.2L engine with a 3.45" bore and a 3.69" stroke. Next, assume an inlet air temperature of about 77F (fairly standard condition).

My engine makes peak power right at about 6000 rpm and VE is roughly 100% at that point. Lets assume IC efficiency is 80%.

Now, hold VE at 100% and intercooler efficiency at 80% as fixed parameters. At this point, we need to pick a compressor efficiency. Lets choose a pretty high one of say 75%.

Next, assume a boost pressure at 6000 rpm of 25 psi. Predicted power at that point is 446 hp.

Now, while keeping all the above fixed (boost pressure of 25 psi, VE of 100%, IC efficiency of 80%, inlet temp of 77F), drop the compressor efficiency to something pathetic like 60%. The predicted power drops to........437 hp! Thats only a 9 hp (or 2.02%) loss in power for a 15% loss in compressor efficiency.

Next, change only IC efficiency to 65% rather than 80% while keeping everything else fixed. So, VE is still 100%, compressor efficiency is 75%, inlet temp is 77F, and boost is 25 psi. Predicted power is now 421 hp, or a 25 hp (or 5.61%) loss for a 15% loss in IC efficiency. At this point it becomes clear that a more efficient IC is more important than an efficient compressor.

The mack daddy for power gains, as Im sure you guys already know, is going to be VE. Going back to the above and holding boost at 25 psi, inlet temp at 77F, IC efficiency at 80%, and turbo efficiency at 75%, yet dropping VE from 100% to 85% will drop predicted power to 379 hp! Thats a whopping 67 hp loss. Magically, that also is a 15% loss in power

I have tested the above thoughts on a dyno and they have proven right every time.

So, in the end, the compressor efficiency is very low on the pole so to speak in finding "free" power. There are many things that provide a much bigger return on investment. My feeling is that one should use the smallest compressor (and turbo for that matter) that can get the job done. I didnt always feel that way as its easy to fall into the bigger is better mentality. But, a few rides in a laggy setup makes you appreciate a well matched engine/turbo combination.

In my case, I have found that the TO4E 50 trim compressor in a 0.50 A/R housing paired with a T3 Stage 3 turbine in a 0.63 A/R turbine housing and a ball bearing center section is the best match for my car and my preferences. It can supply 400 whp (and then some when I turn the wick up )and still spool very quickly (starts making meaningful boost around 2000 rpm) for street use. Ive gone as large as a TO4B 60-1 compressor in a full TO4S cover paired to a Stage 5 / 0.82 exhaust side in testing various combos.

 

Ahh...excellent Turbo calculator. I use that all the time and used it in the above calcs. There are a few of them floating around but the TurboFast one is about as easy to use as you can get and gives results that are pretty close to some of the more sophisticated calculations. I have a spreadsheet that looks at thing alot more closely, but it takes alot more time to use it. For ballpark stuff, the TurboFast calculator is pretty dang cool!

55 trim is a rare wheel used only, to my knowledge, on some Turbo Dodges. It might have been used elsewhere though...who knows.

Keep in mind that the compressor maps are conservative (about 10% from what Turbonetics tells me). You can spin them past the map.

And no I was not spraying!

 

Luke9583...your wish is my command!

Pretty obvious this turbo is running out of air

 

VERY COOL..... I bet that's a fun ride. deffinately coughing but very cool.

C16, or do you mix toulene and ultra 94 in your bath tub like me? hehe

 

I didnt keep the car like that for very long. It was just an experiment as it was wheezing pretty hard!

That was pure 93 octane pump gas.

I havent used C16, but have been trying various ratios of 93 and 76 110 purple as well as some other additives. I can tune to pure race gas, but to me there is no fun in that for a street car.

What ratios of toluene to pump gas have you used? Any idea on how much more timing you can get with the toluene mixed in? Do you add any oil to the toluene to make it "wet" (as toluene is very drying)?

 

More fun like this........I didnt complete this run so it only goes to 4400 rpm, but it sure was looking good

 

LOL

 

I've read a few of those articles also. The resuts time & again were disapointing at best.

 

LOL

 

Through all their experience James and Norwood Performance are now offering several stages of turbo kits and they stand behind their work. James and Norwood Performance are class acts. You won't find anyone that can say anything bad about their real life experiences with James and the Norwood Performance since James took over.[/QUOTE]


I can't agree more whole heartedly. James is the nicest guy you would ever want to meet. I have never met a business owner in any business that cares as much about his customers. I recommend his shop to everyone. I have used his expertise and customer service as examples of how a business should be run many times.

 

"Check the tech section to see how wonderful Norwoods is at fixing cars, let alone modding them"


I mainly read only the tech section and I don't recall a single post about someone unhappy with ANY work that was done at Norwood, quite the opposite. I did a quick search and found nothing. SO I'm a little confused...if all their customers go away happpy, what exactly is it that they are doing wrong???

 

3gallons ultra 94; 2 gallon Toulene; 1 teaspoon of ATF; and 2 teaspoons of acetone

 

Yowie kazowie! Thats a stiff mix of toluene!

Whats the effective octane of that mix? 105ish range? Does it end up being any cheaper than just buying race gas?

Whats the acetone for?

 

acetone is a cleaner, since there is no lead. If you buy enough toulene, it's worth it. I do not buy enough tho. I would be better off running LL av gas.

 

Well, if you look at the sudden rise later on in the rpm band you will notice there is a fair amount of lag. So it is obviously over-sized. IMHO

It doesn't really look like the wastegate didn't open because I would fully expect for the power curve(hp) to rise almost exponetially for a failed wastegate bleed off. It does appear he might have had the wrong WG spring and the boost MAY have creeped up a bit.

Really, for a good turbo size he should be getting full boost no later than 4000-4500 rpm's if not more quickly. I don't know though, it looks awfully close to 4k anyway.

I'd say a nice T60:1 w/ a .56 AR would be nice preferably with ceramic BB.

 

closer to 103 screw the 60-1, if you are gonna spend norwood style money. You should have GT30's on there.

 

Buttmunch? LOL. I think it funny that the LEAST believed and LEAST respected member of the chat group calls anyone else "buttmunch" when clearly, (at least to eveyone else), you are the "buttmunch"! Also, yes, you do need to do some research, unless you'd like to do some "personal" experimentation.
I'll offer you this opportunity:
I just got my R1, riden it less than 500 miles. You, Mr. Big Experience can bring your Lambo, if you can make it start. For $5000 cash, I'll take you on, from any speed, up to 150 mph. This is an open challenge for all on the board to see. I'll drive half way to meet you. We can video tape it and I'll post it for all the F-chatters to see.
Now, put up or shut up, asswipe.

 

"Well, if you look at the sudden rise later on in the rpm band you will notice there is a fair amount of lag. So it is obviously over-sized. IMHO

No..I don't think so. Lag is the time from when the throttle is open to when boost is available so there is no way to show it on a dyno graph, at least that I know of. If your looking at the full boost at 4000-4500 on an engine set-up to pull to 8500. So boost in the top 2/3 and full boost in the top 1/2 of the rpm curve, that's not bad IMO.

"It doesn't really look like the wastegate didn't open because I would fully expect for the power curve(hp) to rise almost exponetially for a failed wastegate bleed off. It does appear he might have had the wrong WG spring and the boost MAY have creeped up a bit."

Again no. What your saying is true if the system is capable of flowing more air, in this case I was saying that it is not. It's basically the same as the graph posted by 4sfed4, which he states is an undersize compressor, althought the TR does drop a little faster. The real answer, posted by James from Norwood (the person who ran the dyno), is that the dyno run was aborted mid-run because the brake on the dyno was malfunctioning. So, the graph means nothing.