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

    • So stock ECU does not like anything above 10 psi?  That Nistune one is just for "try" if it will be any different, I know it need to be tune for that. I know but YOU may know about these problem but i/we dont. They few little Skylines here let alone people who know anything about tham so that is why iam asking here  
    • So now we have a radiator with no attachments whatsoever. It lifts up with a particularly tight spot between the drivers side air box mount and the lower radiator outlet, but if you've got this far you will sort that too. This is the lower mounts with the rad out so you can see where the rubber bushes go, it is a straight shot upwards Done! Assembly is the reverse of disassembly, with blood less likely to be shed.
    • Right, onto the second last trick. The Air Con condenser is mounted to the front of the radiator and stays in the car when the radiator is removed. There are 2x 10mm headed self tappers holding the top of the condenser to the radiator, remove those The bottom of the condenser is attached to the radiator with clips. You need to lift the condenser out of those clips and clear (up, then forward). f**ked if  could work out how to do that last bit with the front bumper on. I hope you can, and you share the trick.  Bumper removal probably deserves its own thread one day once I've recovered the will to live, but basically you need to remove the wheels, front inner guard liners (clips and 10mm headed bolts), the self tapper between the guard and the bumper at the rearmost point of the bumper (same as an R32 that bit), any remaining clips at the top/front of the grill, an absolute bastard design with a plate that holds the top of the bumper above the headlight each side (only 1 bolt which is tricky to get to, but the plate catches 2 places on the bumper and must be removed....carefully!) and push clips between the bumper and guard under the headlight. If you've done all that you will be faced with wiring for the fog lights on both sides and in ADM Q50 RS at least, 4 nasty tight plugs on the driver's side for the ADAS stuff. So, the clips at the bottom look like this on drivers side (looking from the front) And on the passenger side (also from the front), you can see this one is already out Clearance on both of these are super tight; the condenser needs to move up but the upper rad support mount prevents that, and the radiator can't move down far because it is (rubber) mounted. Once you achieve the impossible and drop the condenser off those mounts so it does not stop the rad moving, you are good to go
    • OK, next the shroud needs to come off and there are a couple of tricks. Firstly, there is a loom from near the passenger side headlight to the fans, coolant temp sensor etc and there is no plug to undo.  In my case I was OK to leave the shroud on top of the engine so I just undid the passenger side fan plug and about 10 of the clips which gave enough free wire to put it aside. The fan plugs were super tight, the trick I used was a small falt screwdriver to push down on the release tab, then a larger flat screwdriver to lever the plug out of the fan unit....be careful with how much force you apply! If you need to remove the shroud altogether for some reason you will have to deal with all the plugs (tight) and clips (brittle)....good luck. I removed all of the clips and replaced them with cable ties that I will just cut next time. Also, in the Red Sport / 400R at least, the intake heat exchanger reservoir hose is bolted to the shroud in 2 places with 10mm headed bolts; so remove them (the hose stays in the car; no need to undo it at the t fittings down at the radiator lower mount. Once you've dealt with the HX hose and the wiring loom, there are 3x 10mm headed self tappers holding the top of the shroud to the radiator; remove those.   The shroud then lifts out of the bottom mounts where it sits on the radiator, up and onto the engine out of the way. Simples
    • Ok, disregard my “rate them” comment, sorry for my unrealistic input
×
×
  • Create New...