fast951

m42racer,

When I stated that the AF was rich, I was not making an excuse. Heck the dyno numbers above do not need an excuse. You have been wanting this and that, well just do it. I'll be surprised if any tuner or engine builder would even work with you, enough complaining, it's getting very old!

m42racer

Tony G, That ok. I think certain things should be kept quiet. Its only fair that engine builders keep their parts and designs and knowledge to them selves. Thats normal.

As for Mr. Milledge and who designs his cams. Well its really not that important. He probably wants to keep all that a secret too.

Tony, it really does not matter. Truth be told here, I am stating things here after discussing Cams and Valve Train parts and design with my friend. He has written software that tells the engine builder many different factors regarding spring pressures, RPM's, Spring rates, and alot more. Way more information than I understand. It not only provides data, but puts alot of it into grahpics. With repect to what you and I have been discussing, his program gives very quick information about engine speed verses spring pressures. Raise the RPM and its tells immediately the required spring pressure required on the seat and over the nose. Then it calculated the distance to coil bind, along with the required installed height to obtain the required seat pressure. Want a certain seat pressure, plug it in and it will tell you the required installed height. Want to know about Harmonics etc, it tell you this too. This software is extremely expensive, and only those engine builders who are really serious usually will invest in such products. Ask John if he uses this. I am sure he does, because it is normally required by those who have their cams designed by my friend.

As most will probably ask, I will not give up my friends name for many reasons, in respect for Mr. Milledge for one.

m42racer

Fast951.

good points, well presented.

m42racer

Fast951,

If you come onto this board and tout your wares, better be prepared to take some stick. As long as its not malicous, it should be expected and accepted. After all its only opinions, and we all have them.

To that point, "IF THE EXCUSE FITS, WEAR IT"

TonyG

m42racer

I couldn't agree more.

TonyG

m42racer

Maybe your "boy" (said in jest) could use that fancy scrmancy software to help me size a turbo for my car.

Millede speced out the current setup, but I think the compressor is too small based on dyno testing.

Any high-end software help would be appreciated.

fast951

M42racer,

You are correct, it's an opinion and I voiced mine. If all the good feedback I received is to be considered "stick", then be it, it's not a bad deal at all.

Please continue your conversation, and enjoy the weekend.

fast951

TonyG,

The 60-1 HiFi is not too smal for your application. However, I don't think it's the best match for your engine.
As I recall, this is a street car, so RPM above 6000 will be limited, and I would pick a turbo that is efficient in the RPM where I'll spend the most time.
If you check the graph below, you are in the efficient spot only at high RPM. On 2 different spots (lower RPM) you are very close to the surge line. I'm sure you and your tuner examined the turbo maps before deciding on a turbo. Why did you chose the 60-1 ?

<img src="http://boards.rennlist.com/upload/T60_1map.gif" alt=" - " />

m42racer

Tony G,

Its not what you know, but who you know. I have another college friend who happens to be a Turbo engineer with Allied Signal. It was through him that I got to met the shop who is doing my 951 engine project. He is the Turbo Engineer who is attached to the engine program they do for a manufacturer. He spec'ed out my turbo and with access to information like maps etc, it really pays to know the right people. BTW, I had the great experience some time ago to experience the testing of a turbo at one of their Turbo dyno cells. Whoa! If you email me with the specs of your engine, and the spec's of your Turbo, I'm sure I could get an opinion out of him. Is it a Garrett?

m42racer

From my limited knowledge, but all from my friend, the only way you can match a turbo to an engine is to know the Performance of that Turbo and the expected performance required from the application based upon the air produced by that Turbo. This brings up the best part of all. Its not boost that matters, its the amount of air volume produced at that pressure level.

Fast951 has posted a map. Whats missing is the origins of this map. (Map Axis's). In one direction is the Pressure ratio, P1/P2, (P1 = boost pressure absolute, and P2 been atmospheric pressure).
The other axis is mass air flow, measured in several different units. The other variable is the impellor speed. Unless we measure the impellor speed, we can not know where on any map we are running. We can measure boost, but without knowing the impellor speed, we can never know where on the map you are running, therefore how much air your turbo is giving and if you are running very close to the choke line or the surge line. One of the ways we can see if we are somwhat safe is to measure the exhaust pressure v the boost pressure. If the exhaust is higher than the inlet p, then usually the Turbo has crossed over. Many things can give errors here. The only way is to measure the impellor speed. I don't know many peolpe who measure this. Proper turbo matching and the results they give is the difference between performance and lack of. If you sell Turbo's you should have done this testing. If you BUY these Turbo's, you should ask if this testing has been done. All the rest is guess work. Maps are only useful if used properly.

jimbo1111

Those turbo maps don't mean much if your still using the kkk hot sides 6,8,or 10. So for the most part trial and error is probable how most tuners have chosen there turbos. Now if i were a tuner looking for a bolt on turbo to sell I would have explored the kkk #10 housing since the a/r is closest to what the garretts offer.

I am pleased with the performance of my #8 hotside. It seems to be a decent street turbo(350 pump gas). fast951 seems to have a really good bolt on turbo. I thing is't the #10 hotside that is giving him good results but I could be wrong.

If I were to do it over(witch I might) I would go with The garrett hot side. I have looked at some maps based on garrett hot sides and they look sweet. Paticilarly the T04e gt3037 52 trim compressor with a .73 a/r 84 trim turbine. 78% efficent at 20lbs boost. Any of you tuners think you can hook this baby up to my car pm me.

fast951

Jimbo111,

Very good point. If the efficiency of the turbine wheel is way off from the compressor wheel then you are correct the compressor maps are useless.

You'll find a huge mismatch with the old K27/K26 turbos where the K27 was a 7006.

Back pressure is very important, however using a larger housing alone does not address it.

Check out the 3 turbos in the photo. The rightmost is a K26#8, Middle is a turbo from X tuner, the one on the left is my own design.
Notice the turbine wheel, which do you think is the least restrictive? Whicg will cause the least backpressure?

<img src="http://boards.rennlist.com/upload/KarlTurbo.JPG" alt=" - " />

jimbo1111

Do i get one if am right.

m42racer

Fast951

If only the blind could drive!

I thought this thread was going somewhere. It had the appearance of some good engineering, above the "kick the tires" level. Then you went and spoilt it. Still it is your thread. When your customers come from the Braille Institute, you can use this sort of engineering I suppose.

I'm out of here.

HAPPY EASTER TO ALL.

Simon

jimbo1111

How dare you insult my intelligence. I'll have you know I hold a mechanical engineering degree and a PE. WHERE IS YOURS or your lack of it.

If fast has found a way of reducing back pressure on the restrictive kkk exhaust housings(that has plagued many tuners) on his own and engineering a solution I would think most of us would commend his efforts. I don't see your point. Would you rather see a slew of mathematical equations for him to prove his point.