Jump to content
SAU Community

Recommended Posts

it's always much more challenging (and expensive) to mod an N/A car sucessfully. As NA_R33 said, exhaust, extractors etc will give you a much better breathing engine, but I'd be very careful about choosing which products to use - a lot of the big bore aftermarket exausts will cause you to lose a lot of low end power/torque, which is exactly what you dont want...:)

Link to comment
https://www.sau.com.au/forums/topic/30756-more-rb20de-hp/#findComment-622403
Share on other sites

As an example of what I said above, fujitsubo provide quite detailed info on all of their exhausts - here's what a typical power/torque graph looks like:

LegalisR_torque.jpg

Notice power and torque are way down under 3K rpm, but pick up and improve at higher revs. I'm not saying this is typical of all exhausts, but you do have to choose with care, especially with N/A...:)

Dave

Link to comment
https://www.sau.com.au/forums/topic/30756-more-rb20de-hp/#findComment-622407
Share on other sites

with all due respect, i have driven a R32 rb20de before with catback exhaust mod before... the car actually felt weaker. The torque is almost completely gone becos there's not enough back pressure for that push. dun forget that you are driving a heavy car that needs plenty of torque for that push. even for my car, rb25de, i felt a decrease in torque but gain abit of it back when i fitted in a silencer... its better balance now at both low and high end power.

my advise is just the air pod and thats it. any other mods like ecu or engine internals are waste of money, esp for an NA car.. trust me, i was in your shoes a while ago and decided to concentrate on the handling of the car instead... such as struts and sways, etc...

Link to comment
https://www.sau.com.au/forums/topic/30756-more-rb20de-hp/#findComment-622534
Share on other sites

I have to agree. At my local circuit most of the N/A racers (civics mainly) always use a small bore exhaust to keep back pressure up. On my current car there is a definite difference in the bottom end power/torque when I add or remove the tail pipe baffle. Generally speaking, if you go for an aftermarket exhaust avoid anything too big and make sure it's designed/tuned for an N/A engine...

Link to comment
https://www.sau.com.au/forums/topic/30756-more-rb20de-hp/#findComment-622560
Share on other sites

I had a exhaust made up at my local place for my old GTS, was 2¼" and only had a (large) resonator near the front and a smallish muffler at the back and picked up about 8Kw at the wheels and lost no low down torque, picked up quite a bit in fact. However seeing some GTS's fit 2½" exhausts they did loose low end when redyno'd.. and that includes GTS25's.. but your only going to get fairly small gains no matter what you do in an N/A car... including PVA's suguestion of NOS as I don't think a RB20DE will handle much more than a 50hp shot???

Link to comment
https://www.sau.com.au/forums/topic/30756-more-rb20de-hp/#findComment-622854
Share on other sites

Try and get your hands on the last issue of HPI (high Performance Imports mag. It has a white GTR on the front with 900hp.

The is a great story on a N/A 180sx which the guy is trying to get 100rwkw on a tight budget. At the very least it will give you some good ideas for your skyline

Link to comment
https://www.sau.com.au/forums/topic/30756-more-rb20de-hp/#findComment-623542
Share on other sites

internal work is not required for a 70hp nos kit on a gts25 so i dont think 50hp on the 2 ltr would require ne. People have presumptions that nos destroys engines, when used properly, yes it puts more stress on the engine as with ne modifaction but actually allows the engine to run alot cooler due to the chemical reaction that goes on in the combustion chanber which is very benificial to engine.

Has nebody ever considered a computer capable of a dual fuel curve with extra injectors for methanol on the second curve, thereby allowing the engine to be leaned right out with out pinging due to the much cooler methanol running through the engine and giving a considerable power increase kinda of like not so illegal nos?? just a thought....

Link to comment
https://www.sau.com.au/forums/topic/30756-more-rb20de-hp/#findComment-623891
Share on other sites

Just do a search on it and see how it works. Basically the nos is broken down by the heat of the engine and when it is broken down it produces oxygen, as the reaction requires heat the process thereby draws heat out of the engine and therefor cools it down.

PVA_GLUE: Thats exactly what im saying, Obviously there will be more stress on the internals but the lower combustion temperatures kinda cancel it out, of course this is only when running relitivly small doses, say 50 to 75 hp.

Link to comment
https://www.sau.com.au/forums/topic/30756-more-rb20de-hp/#findComment-624140
Share on other sites

Extractors for a RB25 will set back around the $2500 mark. Thats a rough price so call up, but it's not cheap as far as I know. I agree with the bigbore 3" zorst, unless your car can push out that much it can potentially drop the power levels.

Much like a front mount intercooler on a GTST vs the stock one. Because the air has travel much further it takes longer and looses pressure (aka pressure drop). Thus you may be required to run say 8psi instead of 6psi to get the same power than before you had front mount.

However yes the front mount will handle much more boost anything above 10psi whereas the stock may not

Link to comment
https://www.sau.com.au/forums/topic/30756-more-rb20de-hp/#findComment-625652
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Even more fun, leave all the ADAS stuff plugged in, but in different locations, hopefully avoid any codes!   And honestly, all these new cars with their weird electronics. Pull all the electronics out Duncan, and just shove an aftermarket ECU and if needed a trans controller in, along with a PDM. Make it run basic but race car styled!
    • To follow up a question from earlier too since I had the front bar off again (fking!) This is what is between the bumper and the drivers side wheel And this is the navigator side, only one thing but its a biggy! So basically....no putting coolers in the wheel arches without a lot of moving other stuff. Assuming I move to properly race prepping this car I'll take that job on and see how the computers respond to removing a whole bunch of ADAS modules
    • So I prepped the car for another track day on Wednesday (will be interesting to see coolant temps post flushing out and the larger reservoir, with a forecast of 3-14 being 20o cooler than last time I took it out). Couple of things to mention; since I am just driving the car and not taking a support vehicle, I took the rear seats out and just loaded the back up Team Trackday style. Look at all that space! To cover off removing the rear seat....it is weird (note the hybrid is probably different because it wouldn't have folding rear seats) Basically, you remove the lower seat base, very similar to a r series but it is a clip that pulls forward to release the base rather than it being bolted down. Easy Then, you need to remove the side section of the rear seat on each side. There is a 14mm head nut at the bottom of the side piece, the it slides upwards off a hook at the top to release; you also need to unhook the seatbelt from the loop at the top. Then the centre piece is weird. You need to release/fold the seats forward with the tab in the boot on each side From there, there are 2,x12mm headed bolts holding the rear of each seat to the folding bracket, under the trim between the rear seat and the boot (4x christmas tree clips there, they suck). The seat is out but you can see where the bolts attach to the bracket
    • As discussed in the previous post, the bushes in the 110 needed replacing. I took this opportunity to replace the castor bushes, the front lower control arm, lower the car and get the alignment dialled in with new tyres. I took it down to Alignment Motorsports on the GC to get this work done and also get more out of the Shockworks as I felt like I wasn't getting the full use out of them.  To cut a very long story short, it ended up being the case the passenger side castor arm wouldn't accept the brand new bush as the sleeve had worn badly enough to the point you could push the new bush in by hand and completely through. Trying a pair of TRD bushes didn't fix the issue either (I had originally gone with Hardrace bushes). We needed to urgently source another castor arm, and thankfully this was sourced and the guys at the shop worked on my car until 7pm on a Saturday to get everything done. The car rides a lot nicer now with the suspension dialled in properly. Lowered the car a little as well to suit the lower profile front tyres, and just bring the car down generally. Eternally thankful for the guys down at the shop to get the car sorted, we both pulled big favours from our contacts to get it done on the Saturday.  Also plugged in the new Stedi foglights into the S15, and even from a quick test in the garage I'm keen to see how they look out on the road. I had some concerns about the length of the LED body and whether it'd fit in the foglight housing but it's fine.  I've got a small window coming up next month where I'll likely get a little paint work done on the 110 to remove the rear wing, add a boot wing and roof wing, get the side skirt fixed up and colour match the little panel on the tail lights so that I can install some badges that I've kept in storage. I'm also tempted to put in a new pair of headlights on the 110.  Until then, here's some more pictures from Easter this year. 
    • I would put a fuel pressure gauge between the filter and the fuel rail, see if it's maintaining good fuel pressure at idle going up to the point when it stalls. Do you see any strange behavior in commanded fuel leading up to the point when it stalls? You might have to start going through the service manual and doing a long list of sensor tests if it's not the fuel system for whatever reason.
×
×
  • Create New...