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Does anyone know cam specs and valve clearance for the twin turbo motor? I have an engine dyno program but it is only as good as the info you put into it. Thanks
 
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TT, I have them somewhere from when I degreed my cams verifying my cam gears accuracy. Do you need advertised duration or at .050" for the program? I assume lift in inches as well. I also have the lobe centerlines. I did my engineering thesis for school on some programs compared to a Quad4 Olds engine I dynoed. They are suprisingly accurate but it is rediculous how precise you need to be with your info to be signifigantly accurate.
They usually have crappy inputs for turbo selection. The Supra new car features gives opening and closing timing that I found to be based on .5mm lift almost exact to the usual .004" lift used for advertised duration. Those #s are good enough to use for the program unless they need to be @.050" lift. The cams are assymetrical lobes so they will both come up on a 115 lobe centerline in the program which is accurate. Let me know if you need the .050" duration specs or don't have the NCF book.
 

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JZ1 said:
TT, I have them somewhere from when I degreed my cams verifying my cam gears accuracy. Do you need advertised duration or at .050" for the program? I assume lift in inches as well. I also have the lobe centerlines. I did my engineering thesis for school on some programs compared to a Quad4 Olds engine I dynoed. They are suprisingly accurate but it is rediculous how precise you need to be with your info to be signifigantly accurate.
They usually have crappy inputs for turbo selection. The Supra new car features gives opening and closing timing that I found to be based on .5mm lift almost exact to the usual .004" lift used for advertised duration. Those #s are good enough to use for the program unless they need to be @.050" lift. The cams are assymetrical lobes so they will both come up on a 115 lobe centerline in the program which is accurate. Let me know if you need the .050" duration specs or don't have the NCF book.
No, I don't have the NCF book, could you tell me the .050" durations specs. It looks like the lobe comes out pretty close to what you say but not exactly. The closest I can get it to is 116.5.
 

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TT_6SPD_95 said:
Does anyone know cam specs and valve clearance for the twin turbo motor? I have an engine dyno program but it is only as good as the info you put into it. Thanks
Which engine dyno program do you have? I've got the Motion Software Dyno 2000 and it is pretty accurate. I just can't get the stock turbocharger numbers down pack. Since I've played around with it I've been able to get the torque pretty much matched up with the factory specs but the HP is right at 320 @ 5600 but it goes up to about 335 from there on. Need to get some ACCURATE numbers.
As for the cam specs I believe they are:
Duration- 276 293
Duration @.050 - 200 204
Lobe Lift - .338" .346"
Gross Lift - Same as above
Calculated Lobe Centerline - 116.5
Intake Valve Opening - 21.5
Intake Valve Closing - 74.5
Exhaust Valve Opening - 83
Exhaust Valve Closing - 30

Hope this helps.
 
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Sorry it took a few days but here is what was measured at the valve on my car and jived with the published factory open close timing specs (@ .5mm lift.)

Intake lift at valve .329" dur @.050" 195deg
Exhaust lift at valve .333" dur @ .050" 201deg
Both cams are on 115 lobe centerline.

My cams were on the nuts for factory specs except the intake was off by a half a degree (opening timing). Which of course is completely neglegable. Put the lift specs in and set the lash at 0" in the program.

Hope it helps.
 

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JZ1 said:
Sorry it took a few days but here is what was measured at the valve on my car and jived with the published factory open close timing specs (@ .5mm lift.)

Intake lift at valve .329" dur @.050" 195deg
Exhaust lift at valve .333" dur @ .050" 201deg
Both cams are on 115 lobe centerline.

My cams were on the nuts for factory specs except the intake was off by a half a degree (opening timing). Which of course is completely neglegable. Put the lift specs in and set the lash at 0" in the program.

Hope it helps.
This helps out a lot...thanks. Do you happen to know the CFM that the stock turbo's flow?
 
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That I can say I have no freakin idea! Like I said previously, it is hard to get accurate info to ensure reliable results. You have to fudge things to get values you know are right and then you just threw away principals of accuracy. Its not so bad on N/A stuff but turbos... whew!
 

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JZ1 said:
That I can say I have no freakin idea! Like I said previously, it is hard to get accurate info to ensure reliable results. You have to fudge things to get values you know are right and then you just threw away principals of accuracy. Its not so bad on N/A stuff but turbos... whew!
Thanks anyway for the input.
 
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