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just to add a little bit more fuel to the fire, i believe Emre has a valid point here saying that the mph is an indication of the sort of power the engine is making and 111mph for ~340rwhp is quite low.

The mph (Terminal Speed) has been used many many times with great accuracy to be able to work out the amount of hp an engine is creating. Of course there are other factors like driver, traction, etc, but unless you're missing gears or having a smoke b/w gear changes, the mph/TS should be within -3 or -4 mph from the expected mph according to the power produced by the engine.

For example, a friend of mine (not the greatest driver) with a R32 GTS-T (RB20DET) producing ~290rwhp on a Dyno Dynamics ran a 13.4@111mph in full street trim with 2.5-2.7s 60ft times at Calder Park.

I'm sure that with that mph, decent slicks and hard launch he'd be able to run a low-mid 12s ET which is what you'd expect with that kind of power.

Also, another example, another friend with a VL which was producing ~190rwkw ran a 12.4@105mph. in this case, the mph definitely indicates the amount of power he was running, even though the ET is quite good which was due to a crazy 1.5s 60ft time.

therefore, what i'm trying to say is that too many people these days are coming up with these "big hp" claims but can't back them up by running the expected/appropriate ET or mph at the track.

just my 2c.

RS500, Things are never equal on a drag strip when we talking about amatuers, if we're talking about good drivers then I would agree that the mph would be a decent indicator:D Rob has 340rwhp did a 13.8@111mph, Got Boost has 344rwhp on the same dyno and did a 12.0@115mph. Both cars are making similar power, but there poles apart in mph and 1/4mile times.

not trying to be a smartass but RS500 said that its a good indication between power and MPH within 3-4mph ... now gtst vspec you say that they are miles apart with mph? as i see it the two examples you have given totally back up what RS500 was saying but it seems you were trying to prove him wrong? this doesnt make sense to me?

13.8@111mph with 340rwhp

12.0@115mph with 344rwhp

Those results show that MPH has a lot to do with the indication of power and ET has nothing to do with it (within reason).

Evan

Another thing that will make a big difference is the width of the power band, Rob said he was dropping off boost - whether it be due to the power band not being wide enough to keep the car on boost or Rob just being a bit shy - will make a huge difference.

Also weight makes a big difference, time taken to change gears.. the list goes on - All will have varying effects on the TS - add them all together and you will have unrepresentative results.

Bottom line though, well all see when Rob lets someone like Rev210 or Steve SST borrow it for a night at the plex.....

rb20, I've seen a car run 107mph with only 240rwhp, so it doesn't prove/disprove anything, except that drivers can make a big difference to both the 1/4 and mph.

Steve, Yeah, Rob's car is quite laggy, and if you don't keep the boot in it will fall off boost and you'll loose a heap of time. We'll let one of the good drag racers take it next time and see if we can't improve the time alot:D

Originally posted by RS500

just to add a little bit more fuel to the fire, i believe Emre has a valid point here saying that the mph is an indication of the sort of power the engine is making and 111mph for ~340rwhp is quite low.

therefore, what i'm trying to say is that too many people these days are coming up with these "big hp" claims but can't back them up by running the expected/appropriate ET or mph at the track.

just my 2c.

Rob's gear changes let him down. Explanation for the lowish mph given. Case closed. The turbo setup requires a good flat change or your going slower than stock. Reaching a particular mph requires 'time', less time if you have more power. If you lose time by dropping out of the power band then you lose mph ,end of story.

Agree about the 'big hp' claims and no performance issue. It's an oldie but a goodie.

hahaha honestly I can't drive for shit and its has taken me 4 meets at EC to get to a time I am half happy with and we only get 3 runs per meet, Its a bit of a cop out letting someone alse drive your car as once again why have the power if you can't use it

Hmm, well people are saying that it can't have the power with such slow times, and yet with a decent driver it will make the better times. If you want us to prove it can do it then we'll need a better driver on-board Rob's car.

Originally posted by Buster

....Its a bit of a cop out letting someone alse drive your car as once again why have the power if you can't use it

I could argue that people use the power in different ways, I am sure you dont drive your car like its on a strip every time you leave a standing start, or like its on a circuit in between ALL the time.

But the best reason I can think of is that he knows what the car is capable of, and has a goal to aspire to, ie, a time to get to so he knows he's using the cars potential.

I have never taken my car down the strip, probably never will, doesnt mean I dont enjoy driving it:)

Steve thats good and if its not your thing well its not your thing

But I had many meets that I ran low 13's with a mph of 113-114 but I fianally learnt how to launch and change gears a bit better and bang its at 122mph, Just let him take his time no one said he had to run the great time over night and when he does get it all right he'll shut everyone up thats doubting him and he will of had the self satisfaction of doing it himself

Yeah for sure, I guess we all look/think about our cars in different ways and just becuse we disagree doesn't mean we both can't be right or wrong its all good

I said that about the times and ES I ran because I don't doubt he will run a good time in the long run and I know that ES is a good indication of power once you get your 60ft down under 2 and change gears accordingly :D

Originally posted by Buster

I said that about the times and ES I ran because I don't doubt he will run a good time in the long run and I know that ES is a good indication of power once you get your 60ft down under 2 and change gears accordingly :D

Buster,

gear changes : i guess what we're trying to say is that with a decent enough launch & gear changes, the TS should be an indication of the engine's power.

Although, in Rob77's case, if the power band is very short where he drops out of the power-band after every gear change, then, that's definitely a problem for him to get the ET & TS which his car should be doing.

i would imagine that a car which is that peaky wouldn't be very nice to drive on the street.

Rob77,

we don't mean to dis-respect your car in any way dude with all this jargen above. after our discussion, i'm sure you're car is making the power you are stating, but it's unfortunate u can't extract the times & mph that it should be doing with your setup.

it looks like u might have replace the big 16cm exhaust housing to something like a 10 or 12cm.

good luck anyway dude.

Do a search on "trust td06 stage 2" that will show you my dyno graph, it has a fair wack more midrange now its been tuned. This is the first time I've been down the strip with the new setup and I'm convinced I can drive the car better after I get some more runs under my belt, but I want the track to be fully prepped before I do and I still think I'll take steve-sst or rev210 along anyway, so if I cant drive the car any better they can at least put down a more respectable time. Regardless of how it performs down the track its a 150% improvement on the stock turbo and ecu, the car puts you back into the seat nice and hard unlike the stock turbo, sure its laggy, but what larger turbo isnt.

Originally posted by GTS-t VSPEC

I did try and tell him to flat change, but alot of people are scared to hurt there car.I'm sure the car is good for a high 12, just need to let someone who doesn't care about the car have a go:D

i have NO respect for my car give me a go in your car:shake:

Quoted by Enrico Palazzo

Haha so let me get this straight. U automatically presume that cos a car has .5lt less displacement that it cant make decent power. Are u assuming that between a 3lt and 2.5lt engine that the only determinants in making power is the boost ran and engine size. That is pretty naive and stupid. U cant comapre 2 totally different engines and then say one cant make that much power cos a totally different engine mad xxxx at whatever psi. Like steve said, u just have shown australia what an idiot u r.

Settle down tiger. Having to brand someone an idiot without actually knowing that person is not necessary here. For starters you got it completely wrong.

The engine i quoted is a 2JZ with big cams and on 20 psi would inhale 230 lt/sec of air per turbo, not that far from the stock RB25 on 1 bar. That car has also put the power down on the dyno i use and pulled 129mph down the track. I would suggest it qualifies to be a reference point for me.

Power is deriven from the amount of air being consumed. If you know the certain variables, why can't you compare two different engines' performances ?

For the record, i've never said Rob's car would only have 200rwkw. I said : " On the dyno i use a 200rwkw gts-t will do the same TS." Another with 255rwkw would crack 118mph. Now, from the highly publicised news that Rob couldn't extract the full potential out of his car that night, we know there is more mph in it. How much more remain to be seen but i doubt there will be 7 extra miles in it. Dropping off power during gear changes is a little surprising as well unless the turbine is a real mismatch.

In the risk of repeating myself; all this difference of opinion is arising from incosistencies of dyno outputs. Whether it's because of shoot-out mode used or my dyno being conservative is irrelevant. If Paul's title for the thread was "123 mph from stock internals", less questions would've been asked.

IMO, the new shoot-out mode is good for dyno competitions and even if/when it becomes widely popular, there will still be some that would not use it. I will try it out next time i am on the dyno, possibly this thursday, but the actual tuning of the car will still be done the old way. The history of my car is in the dyno, as is the number of other cars' for comparison after different modifications.

Paul had compared the two below for comparison.

13.8@111mph with 340rwhp - rob77

12.0@115mph with 344rwhp - GotBoost

There is a 100kg difference in between the R32 and R33 GTR, is this the case with the GTS-T as well ?

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