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L67 more power

Kyle H

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hey all i got my car dyno tuned yesterday and i made 171.9rwkw for the following mods:
pacemaker extractors
2.5 inch catback
200 cell hi flow cats
mace cai
yella terra 1.9 ratio roller rockers
shaved heads
yella terra snout with 11 psi (82mm) pulley
stage 2 shift kit in auto

im not looking to change any of those mods listed above im only looking to add more, such as diff gears and cam etc.
but would love everyones opinion on what else to add and what they have done to theirs, im chasing 190+rwkw. thank you all
 

immortality

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Is that a singe 2.5" cat back exhaust?
 

Kyle H

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no its dual, sorry should've added that
 

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More boost + cam and/or intercooler of some type.

Did you put a MAT sensor in the LIM instead of the standard IAT sensor in the airbox so you can tune the timing curve to the actual IAT's under the blower?
 

Kyle H

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More boost + cam and/or intercooler of some type.

Did you put a MAT sensor in the LIM instead of the standard IAT sensor in the airbox so you can tune the timing curve to the actual IAT's under the blower?
i dont know much about l67s im learning as i go so to my knowledge none of those sensors have been changed, im thinking about 13-14 psi pulley w2a intercooler and a cam
 

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This is a common mod for the L67's. The factory system is only measuring the air temp inside the airbox before the blower, with the sensor located in the LIM you can tune to the actual air temps under the blower and you can add/subtract timing based on air temps (as the temps rise and drop). . Talk to your tuner and see what he thinks about it but on the stock tune the PCM starts to pull timing when the air temp in the airbox goes over 32°C IIRC. Much better off getting this table tuned properly.

PICT0042_zps7q6zpkwz.jpg

PICT0038_zpsumm2j55l.jpg


i dont know much about l67s im learning as i go so to my knowledge none of those sensors have been changed, im thinking about 13-14 psi pulley w2a intercooler and a cam

When you fit a cam the 1.9 rockers will become an issue. I'd advise against a crow cam for high ratio rockers as they are ground to suit stock head valve lift limits (.520" valve lift limit). IF you check out the MACE/Comp cams grinds they have more valve lift (into the .530"/.540" range) which can be done with slim line valve guide seals and special valve spring retainers or just have the valve guides machined down a touch.

Another option I haven't seen anybody do in aussie is have the LIM coated with some sort of heat proof coating.
 

Kyle H

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This is a common mod for the L67's. The factory system is only measuring the air temp inside the airbox before the blower, with the sensor located in the LIM you can tune to the actual air temps under the blower and you can add/subtract timing based on air temps (as the temps rise and drop). . Talk to your tuner and see what he thinks about it but on the stock tune the PCM starts to pull timing when the air temp in the airbox goes over 32°C IIRC. Much better off getting this table tuned properly.

PICT0042_zps7q6zpkwz.jpg

PICT0038_zpsumm2j55l.jpg




When you fit a cam the 1.9 rockers will become an issue. I'd advise against a crow cam for high ratio rockers as they are ground to suit stock head valve lift limits (.520" valve lift limit). IF you check out the MACE/Comp cams grinds they have more valve lift (into the .530"/.540" range) which can be done with slim line valve guide seals and special valve spring retainers or just have the valve guides machined down a touch.

Another option I haven't seen anybody do in aussie is have the LIM coated with some sort of heat proof coating.
you really know your stuff mate thank you so much, ill look into a high ratio cam
 

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More boost + cam and/or intercooler of some type.

Did you put a MAT sensor in the LIM instead of the standard IAT sensor in the airbox so you can tune the timing curve to the actual IAT's under the blower?

Hi there,
I'm about to have an L67 rebuilt and I'm really interested in this ... excuse my ignorance but can you let me know if LIM stands for Lower Intake Manifold, MAT stand for Mass Ait Temperature and IAT - Intake Air Temp...?
Any help much appreciated.

Timbo1972.
 

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Correct (sort off)

LIM - lower intake manifold
MAT - manifold air temp
IAT - intake air temp
 
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