I mean, if is doing this to us!!

 

If this is true, then I recommend the California folks to steer clear of Unocal gasoline. If 91 pump octane Unocal gas has a RON of 96.5, then its MON must be 85.5 so that (96.5 + 85.5) / 2 = 91. A gasoline's MON rating is considered a better predictor of knock resistance at high RPMs and high loads than is RON. Thus, you want your fuel's MON to be as high as possible. As a rule of thumb, for any particular pump octane number, the higher the sensitivity, the worse the gas. Sensitivity is defined as RON - MON and most gasoline sold in the US has a sensitivity of about 10. To find out that Unocal 91 octane has a sensitivity of 11 is bad news. Don't put that stuff in your Evo.

 

hey all, just so its clear because most dont know the difference between dynos... dynojet is a hypothetical horsepower rating based off the (although not innacurate and consistent in contrast with other cars) calculation of the speed at which a car can spin a 'drum' which is a certain weight, math is good, so this can be looked at versus other cars and describe a power... yes... but shiv's dyno, one of few in the world, actually has sensors and resistance that see or detect actual power at the wheels, they showed me a dyno of a skyline with active differentials and the thing was so accurate you could actually see a minute horsepower variance wiggle when the differentials would transfer power front to back... very impressive, what is not a for sure thing, is how much his wheel horsepower reflects on motor horsepower as all cars lose different amounts, in regards to his liking the car, he does, and he took me for a ride in his that made my heart pound and reminded me why i sold my gsx for an evo, anyway, good luck to all with your evos/......

 

Claudius-

Shiv is a good guy he reported what he found and is catching crap for it. Please remember he got 228hp out of an Evo 7 RS2 with 93 AKI (S/B about 98.5 RON). So his JDM/Euro numbers compare well with the numbers at G/Force, it is a Dyno Dynamics as well. The included graph from a stock VII at G/Force has much different scaling.

No doubt that the JDM Evo VII makes around 300hp. This should be true for the JDM VIII as well, no reason to believe any different now. If the US version is actually 271 hp then it should be down 20 to 30 hp from the Evo VII or around 200hp on shivs dyno.

Until some one else tests eight USDM Evo VIIIs on their dyno with results within 3 hp from car to car then I wouldn't attack his methods. His results have been very consistent.

The pre-production differences otherwise called ringers has a long history in the US. Everything from cars that are only available with automatics being tested with manuals to outright fraud. The worst case I remember were the Pontiacs tested by Car and Driver in the sixties. They were all delivered from Royal Pontiac. There best work was a ‘63 Catalina that for years had the record for 0-60 times at C&D 3.21 seconds or something crazy. Mitsu is a different company, so I don't know if they have done anything like this in the past or if they are doing something now.

I do know that the USDM Evo exhaust manifold is different from a JDM VII. It is not just the missing secondary air system either. The casting, at least, is smaller. On an Evo VII you can clearly see the manifold under the exhaust shroud. On the USDM Evo I had to really search for it. I finally wedged my hand down between the head and shroud far enough to touch it. Very different. I have only seen picture of the JDM VIII but it still shows it having secondary air piping.

Erik

 

Where can we find the RON and MON ratings at gas stations? Are they clearly labeled?

Mark

 

All Socal 91 Octane gas comes from one place it is a special CBG mix that is required in SoCal. The sensitivity is 10 points. It is no great shock that it is slightly higher than rated. 91 AKI is a minimum standard.

Erik

 

Was there any difference in the break in of the different cars?

For instance what was the break in like for Vishnu's car, as well as the others they tested.
How does that compare to the SCC break in? I know the SCC car already was on 2 dynos and had at least 1 quarter mile pass with 400 or less miles, which is a harder break in.
Maybe there is some truth to the article to breaking in the car hard.

My main point is that speculation is worthless. Lets just wait for proof. I will be going to the track in a few weeks and we can see how mine compares to the SCC number. I am at sea level too so no one has to argue about correction factors or anything.

 

Thanks Erik. That EVO dyno graph you posted even shows the 5600rpm dip that we've seen in so many of our dyno runs. It appears to be a "step" in the raw ignition advance curve. Managed to get rid of it but only after considerable effort in finding out the *exact* engine speed the ignition advance made the jump. Filled it in with 1.3 degrees of additional ignition advance

Cheers,
shiv

 

No they are not labeled. Just the AKI or Octane # which is (RON + MON)/2. I was trying to track this down months ago. EU and Japan use RON only. Some Euro turbo cars in the eighties got into trouble with low MON ratings which is a more applicable rating standard for most high performance motors. The oil companies agreed to keep the sensitivity to 10 points to eliminate this issue.

That is why I was interested in the RON to compare US vs. EU fuels.

Erik

 

I heard this from a pretty reputable source, so I'll take it as true. I saw Shiv mentioning a few times about emission stuff in the Evo 8 causing problems, and I know that America got a different cam to help with emissions.

Shiv, this would definitely account for some HP loss, right?

Couldn't we just import some JDM cams and replace the ones in our Evo?

 

Kinda lame that we have to do stuff like that to get the hp #'s that claims the car has already

"if all the #'s that shiv claims are true"

 

Fireball,

You work at dealership correct?

Claudious talked about that in Europe, the car has to put out the HP the manufacture said it would with a +/- 5 % difference.

Do we have anything like that in the US?

If in fact they did this to pass emissions, the car would not put out 271hp. Correct?


Thanks,

 

No exhaust? Pulling only 180+30=210whp? That sucks! Running more boost than 18.5 and weaker than JDM evo 7. Whats' going on with our engine? Are you sure that's after tweaking?

 

This is beginning to sound like another urban myth. There are 6 refineries in SoCal producing gasoline, each owned by a different company (see http://www.arb.ca.gov/fuels/carefinery.htm). I guess we're supposed to believe that only one of those refineries is producing California Phase 2 Reformulated Gasoline (RFG), AKA Cleaner Burning Gasoline and all the other refineries are producing gasoline that can't be sold in SoCal? And we're supposed to believe that Unocal is actually selling 92 pump octane gasoline at its stations but chooses to label it as only 91?

 

My 2 cents:

Graphs are fun to look at. Some might even go as far as to say they're pretty. If indeed the car is detuned or whatever they may have decided to do, I feel for the 2% of people out there that are going to be racing in a series that doesn't allow for accommodations. As for me though, I'll be happy as long as I'm enjoying myself. I'm sure that'll last a loooong time too.

What does Mitsu have to gain from misreporting anyway? Would you think it'd be in the best interest of a company who is climbing towards the pinnacle of their career in the US? You think they'd blow this off just to save a little money?