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As it should be

And greg pls...no car is kicking out at 30km/h in 3rd gear without a clutch dump on shot tyres in the rain!

There's nothing magical in the Jap 2 litre engines, unless very high comp and E85, that's going to make them more responsive or less laggy than a 2.5 with similar top end power. I'm yet to drive one more responsive than my 2.5 that doesn't die in the ass after the mid range cause of its tiny turbo...happy to be shown otherwise...

I was pretty surprised. Car is running 265 Hankook Ventus RS3's too. Really, REALLY had to feather 1st and 2nd to get it to 100, it was really quite eye opening. I thought my car had no grip (to the point of spending big bucks on a aftermarket traction control system.. which rocks)

But yeah. I was like fark damn okay.

I know your car makes.. 275 with change on a RB25 from memory (pretty much entirely from forum stalking), I would be surprised if it actually felt more responsive than the 260KW SR20, but this may have something to do with car weight.

Not saying there's no difference, I mean I noticed the difference from 2.5 to 2.8! But there isn't a LOT by any means.

from what I've heard (and its all second-hand info if you know what I mean), the last motor was bit warped and you're running stock head gasket on a big power/boost 2.8 setup? i know its a metal gasket, but thats a lot of boost. Tony runs factory, but he's got a big-ass turbo with less boost.

there is talk of an underlying issue that hasnt been addressed causing this warping. wont know till its torn apart.

Yeah, the previous engine had a lot of issues presumably by who it was built. Just having HS put it together resulted in basically having the effect of another stroker kit ontop of it. I made the same power with 10 deg less timing and 8psi less boost, with a good 500rpm better response.

Then it let go. ARP Studs specify 90ftlbs and they put 80 on the blueprint, and it lifted/warped. I suspect the issue was always there mainly because I couldn't actually bleed the f**king thing since I got it, but figured "it'll be OK" until I was emptying a radiator every time I gave it a bootful. (driving it normally around was fine)

I used the head gasket they recommended, which was a 1.1m Permaseal one cause wanted 9:1 CR. Spent the money on a Tomei one this time around, and re-bought head studs so I can confirm a million percent what the f**k is in there.

Yeah I don't buy that wheelspin in x gear stuff...it's like people talking about cars wheelspinning/chirping in 4th...unless 11ty kw, it's almost always ling long tyres with awful camber and shitty clutch work.

In a 260rwkw S chassis with 265 Hankooks, having to tread lightly with the throttle in third is not a success of the engine...it's a failure of the suspension/drivetrain/tyre setup IMO. Our race S15 ran 285rwkw on E85 and third held all the way from boost to redline. 2nd almost did it at full throttle on semis.

The S chassis can certainly give the illusion of being quicker and more responsive because it's lighter, but it needs to weigh around 20% lighter than a Skyline to achieve this...and going back to the original discussion about Evos which are often heavier...they feel like ass off boost compared to Skylines (that don't have huge turbos).

I'd put it down to you (I'm assuming here) not having driven a responsive RB25 that still makes decent power for fair comparison to mildly modified 2 litre engines. If you didn't have such a god awful curse following you around I'd invite you to try mine.

hahahahahahaha, you f**king what mate.

Unpopular opinion here sure, but I reckon without a doubt one of the best mods you can do on a RWD car :P

Re: Responsive SR's and such, I was quite surprised as I was just putting around at the time. I did think as mentioned "ah okay, I can see why they drift these things" after being surprised and shitting myself.

The car does actually grip quite well otherwise, though. Just didn't seem to require any more response because any more response is more than the tyres/suspension setup can actually handle, making it literally useless..

A combination of boost threshold and transient throttle response ;)

It is too much power at too low throttle input/speed/rpm for the tyres to handle, so any more of any of that = wheelspin and thus not actually beneficial at imparting forward momentum!

Traction control light coming on and chirping with auto at 130km/h into 3rd ftw :P

No turbo car feels responsive to me now days, but that's what makes them fun IMO

Edited by UNR33L

No turbo car feels responsive to me now days, but that's what makes them fun IMO

agreed.

but a big cam N/A will always feel slow/laggy when theres no forced induction to pick it up in the mid.

Traction control light coming on and chirping with auto at 130km/h into 3rd ftw :P

No turbo car feels responsive to me now days, but that's what makes them fun IMO

Yeah your car is the opposite

Responsive, but after the initial pull from down low that makes you go woah it doesn't feel as fast as it is after that

You running better tyres yet? Should do some gtech runs again

Unpopular opinion here sure, but I reckon without a doubt one of the best mods you can do on a RWD car :P

Re: Responsive SR's and such, I was quite surprised as I was just putting around at the time. I did think as mentioned "ah okay, I can see why they drift these things" after being surprised and shitting myself.

The car does actually grip quite well otherwise, though. Just didn't seem to require any more response because any more response is more than the tyres/suspension setup can actually handle, making it literally useless..

Sounds to me like this SR just wasn't set up properly...

Well given the car pretty well at DECA and long wang on 1st attempt, and... every Silvia driver that's ever got in it has gone "oh shit, this is how I need to go setup my car" I'm gonna wager with nah.

Unless every RB is setup badly in comparison, it really makes me think the whole SR20,4G63 > RB20 thing really just continues to manifest with the RB25/26 using the extra 500/600CC to make up for the shortfall :P

And this in comparison to my (older, laggier!) dyno result which is here -> which most would say constitutes "quite responsive" for a RB

http://www.sau.com.au/forums/uploads/monthly_06_2014/post-63726-0-07556500-1401681661.jpg

Out of curiousity (slow day at work, I plotted his dyno chart vs your dyno chart....both at racepace!...) and made this little excel graph

really not much in it lol, the part that does is him dropping down from 22 to 16psi at the top end.

post-63726-0-42561800-1444867350_thumb.jpg

Yeah your car is the opposite

Responsive, but after the initial pull from down low that makes you go woah it doesn't feel as fast as it is after that

You running better tyres yet? Should do some gtech runs again

Still running Achilles 245s till I can afford some new rims :P

Well given the car pretty well at DECA and long wang on 1st attempt, and... every Silvia driver that's ever got in it has gone "oh shit, this is how I need to go setup my car" I'm gonna wager with nah.

Unless every RB is setup badly in comparison, it really makes me think the whole SR20,4G63 > RB20 thing really just continues to manifest with the RB25/26 using the extra 500/600CC to make up for the shortfall :P

And this in comparison to my (older, laggier!) dyno result which is here -> which most would say constitutes "quite responsive" for a RB

http://www.sau.com.au/forums/uploads/monthly_06_2014/post-63726-0-07556500-1401681661.jpg

whose car at deca?

there only 1 or 2 cars I would take over my set up and both as they 200+ kg lighter.

Out of curiousity (slow day at work, I plotted his dyno chart vs your dyno chart....both at racepace!...) and made this little excel graph

really not much in it lol, the part that does is him dropping down from 22 to 16psi at the top end.

Is that my dyno plot? In depth research lol

My setup is 16psi throughout, with a laggy IWG highflow inside a Nissan comp cover for stealth. The SR, with what sounds like an over-boosted small turbocharger at 22psi...is not really impressing me. It would be a quick car, but put a smaller EWG turbo on mine that doesn't get choked in the top end...it'll move the graph down 500rpm off the spool and make much the same power as both of us up top, albeit not as stealth.

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