Detuning LM7 to 220HP
Thread Starter
Staging Lane
Joined: Nov 2019
Posts: 60
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Detuning LM7 to 220HP Has anybody detuned an LM7 to around 220HP. In Denmark i can add 20% power over stock in an engine swap without having to pay new registration tax. $$$
I guess pulling around 10-15 deg at WOT should do the trick.
Any thoughts?
I guess pulling around 10-15 deg at WOT should do the trick.
Any thoughts?
TECH Senior Member
Joined: Jun 2016
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From: Central Cal.
The unasked question- Are they measuring power at the WHEELS or the FLYWHEEL?
IF it's at the wheels as Minytrker says above, you might already be close to there since they can't measure flywheel power unless they rip your engine out to do it. Not happening.
IF it's at the wheels as Minytrker says above, you might already be close to there since they can't measure flywheel power unless they rip your engine out to do it. Not happening.
Thread Starter
Staging Lane
Joined: Nov 2019
Posts: 60
Likes: 16
The power is measured at the wheel but corrected for flywheel HP. I pretty much have to show a dyno sheet conducted under some specified EU conditions. It's corrected for 25C and sea level flywheel HP
Thread Starter
Staging Lane
Joined: Nov 2019
Posts: 60
Likes: 16
That would be documented and easy to check for the police. My thought is to maybe also add a lot of line pressure to the trans so I waste more than the 20% they assume.
Maybe also run it quite lean for the dyno session. I doubt it would hurt the engine to do a few lean pulls to 5400rpm or so
Maybe also run it quite lean for the dyno session. I doubt it would hurt the engine to do a few lean pulls to 5400rpm or so
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Verdad Gallardo TECH Senior Member
Joined: Jun 2016
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From: Central Cal.
Too much line pressure is very bad for the trans, and too lean will do damage even in very short term.
There has to be a way to put a "stealth" restriction somewhere that "they" won't detect but is removeable/reversable.
Is a state-owned dyno used, or a private one?
There's always "extra" padding under the gas pedal....
Just so we know, exactly what kind of car are we dealing with here?
There has to be a way to put a "stealth" restriction somewhere that "they" won't detect but is removeable/reversable.
Is a state-owned dyno used, or a private one?
There's always "extra" padding under the gas pedal....
Just so we know, exactly what kind of car are we dealing with here?
TECH Resident
Joined: Oct 2006
Posts: 993
Likes: 173
From: Euless, TX
Too much line pressure is very bad for the trans, and too lean will do damage even in very short term.
There has to be a way to put a "stealth" restriction somewhere that "they" won't detect but is removeable/reversable.
Is a state-owned dyno used, or a private one?
There's always "extra" padding under the gas pedal....
Just so we know, exactly what kind of car are we dealing with here?
There has to be a way to put a "stealth" restriction somewhere that "they" won't detect but is removeable/reversable.
Is a state-owned dyno used, or a private one?
There's always "extra" padding under the gas pedal....
Just so we know, exactly what kind of car are we dealing with here?
Get a spare set of junk wheels and tires for it and foam fill them like logging truckers do. The extra rotational mass will kill your power reading on an inertia dyno.
Thread Starter
Staging Lane
Joined: Nov 2019
Posts: 60
Likes: 16
I'm using a drive by cable setup. I might be able to adjust the throttle cable a bit and somehow fool the throttle reading to show 100%. I'm not 100% sure if that is needed though.
Maybe a hidden obstruction in the intake tubing could work
Maybe a hidden obstruction in the intake tubing could work
is this auto or manual? if auto, like OP mentioned, lower the timing above 4400RPMs from like stock 15* to like 8* and set the RPM shift points at like 53-5600 as to not even hit peak HP.
edit another is run rich, like 1pt richer, ie- current PE is 12.8, set it at 11.8. another is very dirty air filter lol
edit another is run rich, like 1pt richer, ie- current PE is 12.8, set it at 11.8. another is very dirty air filter lol
TECH Senior Member
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From: Central Cal.
Thread Starter
Staging Lane
Joined: Nov 2019
Posts: 60
Likes: 16
It's not to bad if I don't add more than 20% power. If I add more I have to pay registration tax again. That would be around 2000USD for something like this. The worst thing is fuel cost at around 8.50USD a gallon. It's great to daily an old american car though