SL/R230: More power by more air and fuel? Using M112 V8 parts on a M112 V6 engine
Thread Starter
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Joined: Nov 2010
Posts: 382
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From: Norway
350 SL, R230 - 300 SL, R129 - 1964 Corvette Sting Ray Sport Coupe - Porsche 911 Twin Turbo (sold)
More power by more air and fuel? Using M112 V8 parts on a M112 V6 engine
This is nothing i have any plans of doing but i just want to check if this will gain more power
I have been reading a little about the M112 V6 and M112 V8 engine in the SL, R230 and i want to hear what my fellow members here thinks of this?
All parts below are bolt on parts
If you replace the M112 V6 engine with these M112 V8 engine parts:
1. Replace the V6 throttle body with a V8 throttle body (V6 diameter is 68mm while V8 diameter is 73mm throttle body i think) The diameter where the throttle body sits on the engine is the same on a M112 V6 and M112 V8 engine
2. Replace the stock V6 MAF witth the one MAF from the V8
3. Reoplace the V6 oxygen sensor with a V8 oxygen sensor (for better air /fuel ratio)
4. Replave the V6 fuel injectors with the larger ones from the V8 engine (if the V6 engine ECU does not limit the fuel flow)
Any think this will help gain more HP and if so how much?
I have been reading a little about the M112 V6 and M112 V8 engine in the SL, R230 and i want to hear what my fellow members here thinks of this?
All parts below are bolt on parts
If you replace the M112 V6 engine with these M112 V8 engine parts:
1. Replace the V6 throttle body with a V8 throttle body (V6 diameter is 68mm while V8 diameter is 73mm throttle body i think) The diameter where the throttle body sits on the engine is the same on a M112 V6 and M112 V8 engine
2. Replace the stock V6 MAF witth the one MAF from the V8
3. Reoplace the V6 oxygen sensor with a V8 oxygen sensor (for better air /fuel ratio)
4. Replave the V6 fuel injectors with the larger ones from the V8 engine (if the V6 engine ECU does not limit the fuel flow)
Any think this will help gain more HP and if so how much?
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'20 X5 M50i; '17 Ram 3500; Golf Cart; Bikes; Scooters
I don’t have either of these naturally aspirated engines, so I’m using basic knowledge and science to answer your questions.
I think the larger throttle body is your best and possibly only improvement on this list. It will allow more air flow at high rpm, thereby allowing more fuel, and more power. Estimate 5% more.
I think the larger throttle body is your best and possibly only improvement on this list. It will allow more air flow at high rpm, thereby allowing more fuel, and more power. Estimate 5% more.
If the current injectors are not flow limited, then you won’t benefit from larger. Most injectors allow at least 10% more than stock.
O2 sensor simply measures the mixture and adjusts. No change.
Not sure about the MAF, if the V8 has a larger MAF, then probably some improvement at high rpm.
I’d find a used throttle body, bolt it on, reset the ECU, and test it out.
Let us know what you find.
O2 sensor simply measures the mixture and adjusts. No change.
Not sure about the MAF, if the V8 has a larger MAF, then probably some improvement at high rpm.
I’d find a used throttle body, bolt it on, reset the ECU, and test it out.
Let us know what you find.
Thread Starter
Senior Member
Joined: Nov 2010
Posts: 382
Likes: 27
From: Norway
350 SL, R230 - 300 SL, R129 - 1964 Corvette Sting Ray Sport Coupe - Porsche 911 Twin Turbo (sold)
I am not at all sure if i will bother trying any of this and i am mostly just playing with the idea.
But a used throttle body is not hard to come by :-)
But a used throttle body is not hard to come by :-)
Last edited by TheSaint; Dec 30, 2017 at 09:32 AM.
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E55, GLS450, GL63, GLE350
Bigger intake runners and throttle body does nothing for you if your heads won't flow the needed air; in fact, it may make the car slower. Modding a NA engine to produce big power can be very expensive and produce limited results if the modifications aren't tried and true.
Forced induction, that's a whole other ballgame. More air plus more fuel will get you more HP. For each bar of pressure, you double the engines efficiency and hp. Turbos and, fuel injectors, and tuning will give you the power you desire. With that said, I would just upgrade to a 600 or 65, throw a tune on and call it a day.
Forced induction, that's a whole other ballgame. More air plus more fuel will get you more HP. For each bar of pressure, you double the engines efficiency and hp. Turbos and, fuel injectors, and tuning will give you the power you desire. With that said, I would just upgrade to a 600 or 65, throw a tune on and call it a day.
Thread Starter
Senior Member
Joined: Nov 2010
Posts: 382
Likes: 27
From: Norway
350 SL, R230 - 300 SL, R129 - 1964 Corvette Sting Ray Sport Coupe - Porsche 911 Twin Turbo (sold)
Bigger intake runners and throttle body does nothing for you if your heads won't flow the needed air; in fact, it may make the car slower. Modding a NA engine to produce big power can be very expensive and produce limited results if the modifications aren't tried and true.
Forced induction, that's a whole other ballgame. More air plus more fuel will get you more HP. For each bar of pressure, you double the engines efficiency and hp. Turbos and, fuel injectors, and tuning will give you the power you desire. With that said, I would just upgrade to a 600 or 65, throw a tune on and call it a day.
Forced induction, that's a whole other ballgame. More air plus more fuel will get you more HP. For each bar of pressure, you double the engines efficiency and hp. Turbos and, fuel injectors, and tuning will give you the power you desire. With that said, I would just upgrade to a 600 or 65, throw a tune on and call it a day.
As i said this is just a thought i am playing with and i probably wont do any tuning at all.
As you i would get more than enough power swapping to SL55 AMG , 600 or 65 but then again i will get all the ABC problems as well..
There is a reason why i bought the SL 350 instead od a SL 500 - SL55 AMG and that is the everlasting problems that is on almost ebvery ABC equipped SL
So that is why i bought my SL 350 with normal shocks and springs :-) I really did not want to worry about the ABC problems
Anyway there is not much difference of the SL500 and the SL350. I will not call them powerful cars at all
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E55, GLS450, GL63, GLE350
You can do the coil over swap on a 55 easily and the one for the V12 is in the works and hopefully will be complete at any time. Then again, it was supposed to be completed a year or more ago. As far as the HP comment, the 230 SL500 has twice the hp of the 350. Not sure how you can call that not much of a difference?
I completely agree with your ABC assessment. It is an expensive pain and, I personally, can't stand ABC. It gives an artificial feel to the handling and handles some road imperfections very poorly. If I keep my SL, I will do the conversion when it is ready for the V12 models.
I completely agree with your ABC assessment. It is an expensive pain and, I personally, can't stand ABC. It gives an artificial feel to the handling and handles some road imperfections very poorly. If I keep my SL, I will do the conversion when it is ready for the V12 models.
Last edited by BlownV8; Jan 1, 2018 at 04:09 PM.
