Lets say you want 380 bhp and similar torque, how would you go about creating a setup that makes all that power as useable and responsive as possible?
Notch top SR, money is no object (I wish), both internal and bolt on mods, has to be a low mount turbo.
Or are the set-ups people already have at that power efficient as they're going to be?
Last edited by mcleansc; 28-01-2016 at 22:49.
Useable for what? Driving to the shops? Streeto? Bank job?
The key's in the mapping ;-) Any small turbo will be responsive. Short IC pipes, lightened fly wheel and an auto diff will help. The rest is down to the map.
Far more optimisation of things like cams and head flow will net some gains at lower speed to bring torque and turbo response up.
You would almost certainly want a twin scroll turbo to get the best response.
The SR heads are ok, but there is always room for improvement in any casting. Interestingly it isn't something that seems to be chased on most builds up to and over 500hp which I think is a huge missed opportunity.
If you wanted the most response possible from a 2.0l your best bet would be a small clutched supercharger for low speed with a bypass + a larger turbo to get the top end free flowing and take some weight off the compressor sizing.
Last edited by zeppelin101; 29-01-2016 at 06:08.
V8
or diesel itOriginally Posted by dukey
Ive had some responsive engines post 200 ownership but I still look back on my S14 with its 2871r with fondness, it was much better than the bigger turbo that followed it for all round fun and drive ability. Nothing fancy, forged internals, a bit of head work, cams, lightened flywheel and a 2871 mapped to 398 bhp and 400 ftlb by Jez at Horsham. Excellent car and it always felt rabid, even from low down.
Currently scrabble powered - Leon Cupra 280
It's not going to be easy.
You need to quantify "responsive".
Do you just what it have boost and good torque when the revs drop on each gear change?
Or do you what it to pull like it does at 5000rpm below 3000rpm?
Nice flat torque curve, so it will pull well from no rpm all the way to red line.
380bhp? OEM are getting a nice 100bhp/L but have complex sequential turbos. So for someone without a big development budget they will need around 5L.or diesel it
But I have been surprised recently as the next door neighbour had his Pug 106 ECU blow up, got a Corsa for about 2 weeks and then rocked up with a Merc SLK 250 CDi. 200bhp in a RPS13 is good for about 147mph (without limiter). 200bhp SLK CDi does 151mph but it's CDa is 0.594m² v's RS13 0.55m².
How with same power can a car with worse aero drag be faster? Well the CDi has a gearbox input speed of 4250rpm in 6th (max speed gear) so doesn't chew up as much power churning oil in the gearbox. That means more ponies reach the road so it goes quicker. Merc CDi engine and trans in a S13 would do 156mph.
I have refrained from putting the accel curves up.
How many truly successful "tuner" builds of this scheme are there?
SXOC in 'what's best' popcorn starter.
For that I would just use a good ECU and a GTX28XX series turbo.
Come to the weekender, there will be a few cars with that sort of power - go for passenger rides, then quiz the owner on your favourite on how he's done it, would be my suggestion
Having driven a few SRs at that power level I would say it depends on what you want to use the car for as to how you go about it, and also how you drive.
Have a go in a few is my suggestion, and go from there
Not many because of the complexity involved. Really you need more additional controllers than a regular ECU can provide short of the likes of a Motec.
But money was no object in the OP so it would be done properly with the relevant R&D
I don't think you would necessarily pick a "standard" turbo size in that eventuality either, it would need to be a mix and match job.
80Kw battery pack in the boot, an elecy motor (say 120hp) in the drivetrain and you wont know what lag is.
This may not be what you wanted to hear but hey ho.
Nitrous anti-lag. Job done
This.Come to the weekender, there will be a few cars with that sort of power - go for passenger rides, then quiz the owner on your favourite on how he's done it, would be my suggestion
Having driven a few SRs at that power level I would say it depends on what you want to use the car for as to how you go about it, and also how you drive.
Have a go in a few is my suggestion, and go from there
Mine will be 380+ and i'm going to be running tomei cams and gtx2867r
Yes I as thinking similar thingsNitrous anti-lag. Job done
Anti lag on the s14 rally car on here (I think username Croatian?) works very well it seems,
watching the video's it has near instant boost response when he is on and off the throttle
and no reports yet of it melting things/killing turbo's, (if unlimited budget,a melted turbo is no biggie
the nitrous idea could be a proper electronic controlled set up like a fogger so it's a progressive power hit
so you could spray it on corner exit and get a smooth surge of power,
don't want a sudden dollop of power overwhelming the tyres grip and defeat the object of pulling hard out of a corner
set up correctly nitrous will make it run cooler and it makes near equal torque/hp numbers so like a supercharger
with the torque gain but with out the complications of fitting a 'charger to a turbo motor
this is going on the idea that you had deep pockets,clever ECU's/multiple sensors to control it all,
and a friendly dyno operator who knows what he's doing and can spend possibly days setting it all up
and as mentioned before me the mapping is the important bit to get it to work perfectly/reliably
and if the engine makes around 380 whp any more torque on the stock box may kill it
the limiting factor of my CA build is the weak gearbox,swap in a stronger box and the driveshafts may be next part to fail
Lag is fun though..
Easier to source a 100bhp electric motor from a Leaf?
McLaren E-motor (like they will ever sell one to anyone, don't even answer E-mail asking for rotor inertia) is supposed to be 170bhp peak but suffers a big drop in output in continuous use. There are product assessments of Nissan Leaf that suggest it doesn't drop much between peak and continuous. Leaf has single reduction gear, E-motor would need a 5 speed to keep it on the boil. Even if run at peak it needs a 3 speed as if geared to max out at top speed low speed acceleration is crap (unless you can fit it in a 1/2 ton Lotus 7). Gearing down to give wheel spinning potential in a 1300 kg car limits top speed. E-motor has lower torque but revs to 18,000 rpm v's Leaf at 10,000 rpm. (hell it's like a 4pot turbo v's V8 argument)
I'd take 2 x Nissan Leaf motors direct to a 4.6 diff. If you stuck 4 of them in then you need a long diff.
Last edited by skyshack; 29-01-2016 at 18:57.
Street driving, potentially a bank job, not a lot of room in a S-Body for the gold bars right enough. I guess it's more about getting the most out of every mod you make to the car. If that makes sense. For example mines has a decent-ish spec, HKS GTSS which is small and fast spooling, has a JDM 4.083(?) diff and tbh I've noticed not a lot happens below 3,000rpm. That got me thinking if I go for a bigger turbo that'll get worse, so how would one set about configuring their SR to be immediate and responsive.
Oddly enough headwork, brian crower cams and springs and a GTX286r was exactly the route I was thinking of going.
Responsive probably wasn't the best word of choice, immediate may be more apt? Cut the lag as much as possible and maybe have the motor run more efficiently as opposed to slapping a turbo on and getting all your power gains from that, if that makes sense? Or is possible.
Didn't even think of nitrous or anti-lag, which weird as I'm a Street Outlaws groupie.. I even used the word 'motor' earlier. Anti-lag would be insane, but maybe a little too insane.
Coming away from 'money is no object', lets say you were thinking of an engine swap, 1JZ or a 1UZ and turboing it, not doing any of the fab work or fitting yourself and you then decide instead of buying, tuning and fitting one of those to the SX, why not invest the money in the perfectly healthy SR you already have. Could you make the SR compete with the 6 and 8 cylinder engines, at that 380 power figure on that budget? By the way this all hypothetical, I'm not masterminding some amazing SR build, just bored and dreaming.
There really is zero replacement for displacement, regardless of what you do, if you fitted the same setup to just a bigger capacity engine that was identical in every other way it would produce more torque.
A 4 banger turbo with any decently sized turbo going for over 300 is never going to be what I would call responsive, even my other half 13 that has a k03s is just about what I consider responsive .
Responsive is just different on a turbo car, on my e36 I can slap it in 5th at 20mph and it starts pulling immediately, I've gotten so lazy driving it around town I just pull away in 3rd gear due to having lot of low down torque, but that's the nature of a turbo car, getting above 3k and pulling like a train, at the end of the day, any time you actually want to make progress you're going to be above 3k rpm, so why does it matter so much that little bit lower down?
Agree that increasing capacity is a way to gain power,low down and throughout the rev range
thing is the cost V's the gain on the SR, I would at best guess going 2.0 to 2.2 20>30 max hp/lbft gain on its own
for what ever a stroker crank ,rods+pistons,machining/labour etc costs,Tomei did a 2.4 kit iirc,and was lots of ££££'s
if it was a yank v8 you can get much bigger CC's gains for far less money
but if we stick with the SR and improving response ,there is a possible loss in response from a heavier rotating assembly
and increasing crank stroke tends to make an engine less revvy ,
in a unlimited budget theme the crank/pistons etc could be made super light to counter act that,
seen titanium and aluminum used for con rods,
scroll down for some awesome windowed pistons + Ti rods http://www.quartermile.ws/forum/index.php?action=recent
can't use Ti for cranks it is a fussy metal imo and likes to crack when flexed or stressed like a crankshaft would
my Dad knows way more about Ti from aerospace,airplanes,it gets too technical for me to truly absorb and store
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