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-   -   red manifold / t-76/ idle ...WHY ? (https://www.rx7club.com/single-turbo-rx-7s-23/red-manifold-t-76-idle-why-391149/)

sevenin7 01-31-05 02:58 PM

red manifold / t-76/ idle ...WHY ?
 
Hi guys
A friend of mine , 2-3 weeks ago , he start his fd with T-76 turbonetics , motec ecu etc . The engine is new and the car runs for 1000 kilometers approx until now without boost .The car at idle , works with 12.6 - 12.7 a/f ratio , and on greddy exhaust temp qauge we see max 700 . The qauge is not in the downpipe , but in the manifold .
Why the manifold turns to red color ? Where is the problem ?
I think 12.6 - 12.7 is good for idle a/f ratio or... not ?
Thanks in advance !

dubulup 01-31-05 03:32 PM

seems way rich.

is anything ceramic coated?

what is the manifold made of?

sevenin7 01-31-05 03:42 PM


Originally Posted by dubulup
seems way rich.

is anything ceramic coated?

what is the manifold made of?

Is a custom ss manifold !

sevenin7 01-31-05 04:39 PM

no ceramic coated !

RETed 01-31-05 07:03 PM

Engine not broken in yet.
Fuel still spitting out the exhaust.
If the ignition timing is correct, the engine still needs to see another 2000km's.


-Ted

EFINI_RX-7_RZ 02-01-05 12:57 AM

If the ISC can't stabilize idle below about 1100 rpm, let's say because of a large enough air leak somewhere past the throtle body, the computer will try to get a hold on the high idle speed by retarding ignition timing heavily enough to get the manifold red hot. If your friend is using a PFC, there is a an option at "etc."/"Function select menu"/"5. Idle-IG Cntrl" (using the commander, don't know where on a Datalogit menu), which allows you to de-activate this operation mode. You will inmediatedly see the engine turning an even faster idle. If so, then find that leak and plug it baby.

edit: ok, sorry, didn't read it has MOTEC, never mind then...:banghead:

edit 2: but maybe, JUST MAYBE, the MOTEC ECU has got a similar operation mode. :scratch:

sevenin7 02-01-05 09:35 AM


Originally Posted by EFINI_RX-7_RZ
If the ISC can't stabilize idle below about 1100 rpm, let's say because of a large enough air leak somewhere past the throtle body, the computer will try to get a hold on the high idle speed by retarding ignition timing heavily enough to get the manifold red hot. If your friend is using a PFC, there is a an option at "etc."/"Function select menu"/"5. Idle-IG Cntrl" (using the commander, don't know where on a Datalogit menu), which allows you to de-activate this operation mode. You will inmediatedly see the engine turning an even faster idle. If so, then find that leak and plug it baby.

edit: ok, sorry, didn't read it has MOTEC, never mind then...:banghead:

edit 2: but maybe, JUST MAYBE, the MOTEC ECU has got a similar operation mode. :scratch:

What is ISC ?

EFINI_RX-7_RZ 02-01-05 11:16 AM

Idle Speed Control Valve

J9R8 02-01-05 12:27 PM

What is the timing at idle? 700C at idle is pretty crazy. It will be decent for transients as you sort of have antilag enabled.

zinx 02-01-05 12:39 PM

Make sure your leading plugs are firing.

RETed 02-01-05 01:28 PM


Originally Posted by J9R8
What is the timing at idle? 700C at idle is pretty crazy. It will be decent for transients as you sort of have antilag enabled.

I think the 700C was for max EGT at any one time.
EGT's that cold in the manifold implies you're running too rich.


-Ted

sevenin7 02-01-05 04:53 PM


Originally Posted by RETed
I think the 700C was for max EGT at any one time.
EGT's that cold in the manifold implies you're running too rich.


-Ted

The egt's is 600-650C at idle ....and the car has 12.6-12.7 a/f ratio .......So why the manifold turns to red
I can't undarstand

J9R8 02-02-05 12:34 PM

Check the timing, or rather you might try advancing the timing a bit, after verifying the timing at idle speed and load areas of the timing map. Again what is the timing at idle (degrees), and what is your idle speed (rpms) and load at that speed (mmHg, kPa etc)?

fdracer 02-02-05 01:50 PM

doesn't make sense, even if the ignition was too retarded resulting in basically an antilag condition, this would show up on the egt's.

jreynish 02-02-05 04:25 PM

how thick is the is the material.

RETed 02-02-05 06:54 PM


Originally Posted by sevenin7
The egt's is 600-650C at idle ....and the car has 12.6-12.7 a/f ratio .......So why the manifold turns to red
I can't undarstand

Idle EGT is too high, unless we're talking about flogging under high boost and taking the reading immediately thereafter?
Let the idle settle down a bit after driving it - it should be more like 500C to 600C range.


-Ted


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