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i am looking at getting a 6m for only 420. i know a 7mgte is the way to go but i want a 6m with headers and then i want to supercharge is. first how much power o the ground is really put down. and also if someone has a supercharger already on one can you post some pics and telll me what you think about it. also i think this forums is the best all you people are awesome. thanks :lol:
 

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Go to the top of the page........ Locate the "search" button...

For a topic, type in "Supercharger". Start reading the various postings.

Supercharging a 5M/6M has been discussed here in the past, everyone has pretty much said why bother??? Go turbo.
 

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in finding out how much power catually gets to the floor you should take away a quarter to a third of the hp and that's a pretty good estimate of how much will go to the wheels.
 

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actually its 18% of the brake horsepower (horsepower at the flywheel) gets taken from the net horsepower (wat comes out ur wheels) so do the math. so if u get like say 180 horsepower at the flywheel, u just take off 18hp which equals 162 and thats wat the horsepower ull actually feel is. i dont even get why they have brake horsepower, sorta useless, unless ur working on tranny's i guess
 

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thanx i wasn't sure hoe much it was i always took a quarter of the power off...guess they aren't that bad afterall.
 

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A good running 6M should dyno around 150-160hp to the wheels and 165-175 ft. lbs of torque. That's with basic intake & exhaust mods. They were rated at 190hp in Japan. Beware of used ones....they could have issues - not uncommon in used engines that have been sitting around idle for years.

Phil G.
 

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actually u cant go off japan they have their own standard of rating horsepower i believe its called J.I.S i forget wat it stands for but i think its iek Japanese Sumthing Standard ::shrug::
 

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Not in this case.

The 6M's 190 HP crank rating is assuming that you're using a 6M ecu. If it's a 5M ecu, then the crank rating might be a little lower. Several have mentioned in the past that the 6M ecu has a more aggressive fuel map.
 

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KesekiSupra said:
actually u cant go off japan they have their own standard of rating horsepower i believe its called J.I.S i forget what it stands for but i think its iek Japanese Sumthing Standard ::shrug::
I've heard this before as well. And it could explain why the 6M is rated at 190 HP in the Japanese market but no one that gets one in N America seems to achieve those numbers, even with a nice intake, headers, no cat, high flow exhaust, AFM mod, advanced timing, etc. Those mods cumulatively add about 20 crank HP (or more) to a 5M, so you'd expect the 6M to respond in a similar fashion. So you would expect 210 HP *.85 = 179 RWHP. Has any 6M achieved this on a dyno?
Japanese market 5M's in Supras were rated at 175 HP from 82-86. Why were N American ones rated at 160 HP max? Was it really a different fuel map or just a different rating system? I've never seen anything concrete to prove to me which is the true cause of the difference.

Also, as DKJones alluded to, the BSFC (brake specific fuel consumption) of the 6M was lower (it got better gas mileage), so you'd think that using a 5M computer to run a 6M motor would not cause you to lose much if any HP as it should make it run a bit richer. See data here: http://www.geocities.com/MotorCity/Pit/9975/dataBySubject/FuelConsumption.html


Sorry, I don't have the answers, just lots of questions.... :?:
 

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The way horsepower is measured in Japan is different to the way horsepower is measured in North America. Japanese horsepower is called JIS Horsepower, North American horsepower is called SAE Horsepower.
JIS stands for Japanese Industrial Standards
SAE stands for Society of Automotive Engineers

A horsepower is actually defined as doing the same amount of work around the world. Where they differ is the conditions under which they are measured.

In a nutshell, JIS Horsepower is measured with colder and higher pressure air conditions so that the exact same engine makes more horsepower because it is being fed more air.

EEC: European standard. Measure at 99kPa and 25°C. Rated in kW.
SAE: American standard. Measure at 99kPa and 25°C. Rated in hp. 1kW = 1.341hp (SAE).
DIN: German standard. Measure at 101.3kPa and 20°C. Rated in hp (ps). 1kW = 1.360hp (DIN).
JIS: Japanese standard. Theoretically same as DIN, but we always find it is actually smaller.
British horsepower: same as SAE. Rated in bhp (could be confused with brake horse power).

In other words, 300hp (SAE) = 300bhp (British) > 300hp (DIN) > 300ps (JIS)

Having said all this, if you take a 161 SAE HP engine and use the above conversion factors, it should make 163.28 JIS HP.

I think the main differences are bragging rights and they like bigger numbers in Japan.
 

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Dean,

I wouldn't be at all surprised to learn that they leave accessories off.

In a web search, several sites said said that DIN (and I assume JIS) was measured at the rear wheels, not at the flywheel, but that HAS to be wrong. There is no way that a 5M-GE makes that much more power in Japan at the wheels than one in North America makes at the flywheel.

I haven't found a JIS document that details everything in horsepower measurements.

Just looking at the increase in displacement from a 5M-GE to a 6M-GE, 2.8 to 3.0 litres, that is a 7% increase.

Ignoring subtle changes like fuel map differences and applying a 7% increase in horsepower from a 5M-GE rated at 161 SAE HP, one would get 173 SAE HP.

Dale
 

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I guess the only way to know what that difference (SAE #'s VS JIS#'s) really is would be to crank-dyno a blue-printed 6m at 101.3k Pa and 20C with 6M ecu, Japanese fuel and no egr. (sounds like a $$$ experiment) Or do the same with a 5m and like ecu. That would show whether the JIS #'s are inflated or not. Though it sure would be nice to know what a 6m is with a 5m ecu as well. (I was told 200hp when I got mine.) phhht! :roll:
 

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there may be a way around the hp dilemma. The 5 and 6mge
hp/torque vs rpm curves show 5mg torque in lb-ft and the 6mge curves show torque in Kg-m so all we have to do is convert the 6mg torque curves to lb-ft to compare. also, these curves show the a/f ratio and that the 5mg is richer above 4krpm. this means that a 6mg running with a 5mg ecu will produce MORE power than a 6mge running with a 6mge ecu. a richer mixture causes the charge to be cooler which results in more airflo.
 

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not necesarily. I've heard our engines run a little too rich for ideal power. I've also heard that pentroof combustion chambers respond well to a slightly leaner charge then some other designs. Knowing how conservitave toyota is, I'm sure they richen the 5m tuning up more then needed just for safety. With the better fuel in japan they can probably get away with running a little leaner. Basicly I'm saying I wouldn't be suprised if the 6m ecu makes the 6m run leaner then the 5m one does, which would be just another factor in the dissappointing power they put down here. Also I imagine the 6m ecu runs quite a bit more timing advance as well.
 

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forget about my torque comparison suggestion since the curves are measured at different atmospheric conditions. the last few lines are still correct tho.
 

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My car (6M) made more power the richer it got. This is with 210cc injectors and 5M ECU. 5Ms also don't have a pentroof combustion chamber. My theory is that 6Ms make 175hp in later model MkII when install, 180hp tops. Making 18% more power (190 vs 161) on ~7% (3 vs 2.8 ) more displacement doesn't jive, especially when the engine and EFI system are so similar. Comparing JDM 5M vs 6M you get about an 8.5% increase. Hence my 175hp claim and it also seems to match the ~150rwhp (-15% drivetrain loss) you get on a pretty much stock dyno 6M MkII. This also make the 160ish rwhp #s make sense on modded 6Ms.
 

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SAE: American standard. Measure at 99kPa and 25°C. Rated in hp. 1kW = 1.341hp (SAE).
DIN: German standard. Measure at 101.3kPa and 20°C. Rated in hp (ps). 1kW = 1.360hp (DIN).
JIS: Japanese standard. Theoretically same as DIN, but we always find it is actually smaller.
Atmospheric conditions account for exactly 4% of the difference. So 4% of
170hp is 6.8hp which should be subtracted from the hp difference due to different measuring conditions.

The only unknown thing afaik is the relative agressiveness of the 5-6mg ecu spark advance as mentioned earlier in this thread.
 
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