hi guys,

i'm curious about the discrepancy in horsepower figures achieved tuning evolutions between the usa and the uk.

i've seen a lot of dyno sheets from uk cars, and with the std turbo, i don't think i have ever seen anything higher than 400 hp at the flywheel. in fact, most cars with everything modified except the turbo only seem to achieve around 380 flywheel hp at the most.

now on this forum, it does not seem uncommon to see dyno sheets of cars with the std turbo producing well over 400 wheel hp. how much flywheel horsepower would this then be? i thought standard estimate of transmission losses for an evo were 24%, so:

400 whp = 400 / .76 = 526 flywheel hp

so what is the explanation for this discrepancy?

i brought this up before, and someone explained to me the octane level of pump gas is considerably lower in the uk. that could be part of it. also, i think somehow my calculation of transmission losses may apply for the rolling roads in the uk, but not for the rolling roads/dynos you use in the usa.

could you guys help me understand?

brandon

 

no comments?

 

Better tuners in the US

 

i think japan has better tuners, all of the US tuners just cry about who's better, can i move over there with my evo?

 

yep, japanese seem absolutely nuts about their cars. but...

the point i am trying to make here is that the guys in the uk have a lot of experience tuning evo's, and it seems that 400 flywheel horsepower is the upper limit of std turbo.

so how are people claiming things like:



maybe i am not understanding how to calculate flywheel hp from this wheel hp number. could someone help calrify this?

 

he used race gas (100octane)+bunch of mods

 

I am the one who explained the differences in pump gas in the UK and the USA....but I also mentioned that the majority of dyno's in the UK are dyno dynamics style dyno's which read much lower wheel HP than a dynojet dyno. Dynojet dyno numbers also correspond very close to what you see in the real world when you calculate HP based on the weight of a car and it's trap speed in a 1/4 mile run.

Typically an AWD dynojet, or an AWD dynapack dyno will have about 12% to 15% difference from flywheel HP...not the 24% to 26% seen on a dyno dynamics dyno. So to use your example 400 wheel HP / .86 = 465 flywheel HP.... much more reasonable and believable. The same car on a dyno dynamics dyno would show right around 350 HP at the wheels.

Does it all sound reasonable to you now?

Keith

 

not sure where this info comes from, we use 98 octane (RON) petrol (gas) over here.

As for dynos dont worry about it, there are so many variables that can affect the reading that the figs dont mean ****e anymore these days, especially as people cheat and use race fuels etc to get better results.

What is important (but cannot be accuralty measured) is the torque, this is what the UK guys are concentrating on, we want massive torque from our cars as this id what makes the car accelerate quicker.

 

hello again keith!

thanks for taking the time to reply

well, i thought about this some more, re-read your previous post, and well.. your right!

one thing that caught me out a bit is that so often people are mapping there cars with race fuel, and so right away there is a certain amount of shock when you see these numbers. i'm suprised people do this because they probably won't be driving with race fuel everyday, and pushing that much more additional power could cause problems with std internals. but i guess they just want a lot of power, temporary or not.

here is your original post keith that i re-read, and can now say makes sense to me:

so this makes sense. in the usa, people are achieving about maximum of 415 hp at the crank, while in the uk, a maximum of about 390 hp. taking into account the octane differences in pump fuel, this perhaps seems reasonable. does about 25 bhp = 2.5 octane (AKI)?

thanks much for your time again keith and hello mud

mud, the thread where keith explained the octane rating differences is here

brandon

 

I don't have a dyno graph for our pump gas tune, but ultimately we achieved 350hp and 330-340ft/lbs to the wheels on pump gas. The ignigition timing on the pump gas AEM EMS map is retarded more than the stock ecu. We think we had bad gas, cuz we were getting knoise(engine knock) with very little advancement in timing. When we tuned on the race gas to achieve 411hp and 400ft/lbs the knoise went away.

The pump gas we used was Mobile 1 93oct

 

Name a platform where US tuners don't make more HP than Japanese/UK tuners...
NONE
4G63
2JZGTE
B-Series
It's just the facts...

The budgets on the US Teams are often far less than these huge JDM tuner shops. While there cars are awesome with trick parts and whatnot... they don't perform as well as the US tuners. Look at what Bullish and Vinny Ten have done with the 2JZ. Probably because the US Teams have alot of experience and alliances to draw from...NHRA, Nascar, NMRA, etc. Look at the Scranton brothers...Went from Modular V8's to Toyota technology. I expect ALOT of 6 second pro-class cars this year. I saw AMS's Evo 2 go 9.7 this is without a huge budgets or JDM titanium trickeration . I also expect a dozen 10 second Evo's a year from now. Probably safe to say there will be a street-driven 9 second evo this year also.

 

Hey Brandon, good to talk with you again!

Well, many of us need maps for both pump gas and race fuel. Personally, I like to be able to run with the catalytic converter and on pump gas in day to day driving, AND be able to drop off the Cat, pour in some race gas, and up the boost a few pounds when I head out to the track. To me this is the beauty of owning a turbocharged car... the ease of changing the boost level to match the fuel you are currently running is only available with a turbo

Here is another thing for you to think about... 100 octane AKI unleaded race fuel {(105 RON + 95 MON)/2 = 100 AKI)} cost about $1.14 per liter (slightly more than double the cost of premium pump gas).... how much does pump gas cost per liter for you? If I did choose to run race fuel at all times I could do it without really straining my budget to much.

Keith

 

Also, octane is calculated differently in the US than it is in the UK. UK uses the raw RON number. We use the (ron+mon)/2 formula.

So while our 93 octane fuel has a lower octane number than the UK's 95, the potency of the 2 fuels is equivalent.

SC~

 

typically, wouldn't you also need to switch to a new map with the ecu in order to take advantage of the race fuel? i agree, i'd like to have a fully programmable ecu, and have maps for different types of fuel, but i just have a plugnplay ecu so am stuck with one map.

i live in the caribbean, and i actually am unsure about the octane rating of the fuel we get here. i'm gonna look into this. but, yes, i understand what you are saying, race fuel is cheap, and that would be nice to have the car running that quick, but the bhp levels are a bit scary for std internals which seem to be good for only about 400bhp from what i've read.

well i don't speak japanese, so can't speak for them. and in terms of the UK, in their defense, they don't have the drag racing motorsports to draw from as you mentioned. but.. right now the norris designs evo 7 did a 10.1 and is completely street and.. is driven on the circuits often so is also not just for dragging.

so in terms of usa vs uk evo tuning, it seems they are in the lead currently. although i may stand corrected as i am not completely up to speed on the state of usa evo tuning.

where are all the companies that had so much experience with dsm's? if the 4g63 is a platform they have so much experience, why are there not some evo's in the 9's in the states?

 

That was my entire point about the dyno sheets on race gas.... it isn't cheating, it is just showing what you made on each fuel as you tuned for it. For example, on my almost stock EVO (AFCII, air filter, and boost controler) I made 269 HP on pump gas and 303 HP on 100 octane unleaded race gas. I made no secrets about what fuel was used for each of the tuning sesions/dyno sheets when I posted them up long ago. What plug and play ecu are you running?

Everything I have seen shows you can run over 600 HP at the flywheel on stock EVO 8 internals with no problems in the short term....nobody knows about long term yet


The engine is reversed 180 deg from the 4g63 in the DSM's so it takes a bit of time to design new intake manifolds and exhaust manifolds to bolt up to this setup. All pipeing is different from intercooler pipeing to the exhaust pipes. They have the knowledge, it just takes a bit of time and money to implement that knowledge on a totally new platforme....even if the engine block itself is the same.

What is the fastest times UK tuners are getting in an EVO 8 on the stock turbo? Buschur has run 11.66 @ 117.88 on the stock turbo and stock block. Expect some 10's and 9's out of him this year now that he has developed a new bolt on turbo system.

Keith