SKYPER

Thanks. Chassis should be identical, shape wise.

Awesome modelling. Does anybody know where I can find properly scaled reference images for R32 GTS, as there only seems to be R32 GTR or R33, R34 stock and racecar reference images???

You're welcome. From what I can understand from the link below (need to scroll down to under the Fig 1,2,3,etc), JJ means the same size rim as a stock rim (I presume diameter) and JR is the tyre that fits on that type of rim - http://www.freepatentsonline.com/4034792.html I think some fit 1 over size like 235 on 225 rim with stock R32 GTR rims. But from what I can remember it makes the side walls of the tyre bulge and not sure how safe it is. If you want more grip, could fit drag spec Nitto tyres on the rear or fit semi slicks or slicks but don't drive when the road is wet.

If they are the IMPUL rims with different width from front to rear, they can have it stamped in different places. For the front it should be stamped on the rim facing the outside of car (you need to remove the trim in the centre of wheel to see it). For the rear it can be stamped on the centre of rim, facing the brake rotor. The rim diameter, width of rim should be stamped there like for example "16 JJ 9".

Motec ECU can plug in like the PowerFC but needs a custom adaptor loom that has the correct plug for engine loom on one end and plug for Motec ECU on the other end. The good part about Motec ECU is it can fit in any car with the right adaptor loom. PowerFC is more of a one engine only type of ECU unless adapted to fit on other motors like R32 RB26 PowerFC on a R32 RB20. Also I think Motec ECU has higher resolution maps which helps with fine tuning the shape of the power graph and extra features like what everyone else has already said. Motec ECU can be used on a Methonal or Nitro engine.

S1 tune engine part info should be on the Omori factory part of the Nismo website - http://www.nismo.co.jp/shop/shop/omori/engine/s1/index.html Although you might not be able to web translate the PDF's as they are in Japanese - http://www.nismo.co.jp/shop/shop/omori/pdf/index.html Use either Google or Babelfish translater for Nismo website. Google - http://www.google.co.nz/language_tools?hl=en Babelfish - http://babelfish.altavista.com/

The stock BOV can be modified to flutter and not leak after 10psi. All you need to do is remove the stock BOV and plug the small hole next to main valve. Also Tomei has instructions on how to do this mod. Here's an American version of the stock BOV mod, but is adjustable - http://www.thedodgegarage.com/turbo_bov_mod.html

I found these video's on Youtube of Alan Grice racing the R31 GTS-R around 1988. Part 1 - http://www.youtube.com/watch?v=UiOnKKJjaWE...feature=related Part 2 - http://www.youtube.com/watch?v=OIyuo0wIUuY&feature=user Part 3 - http://www.youtube.com/watch?v=6Q9g3CTAZFw&feature=user Part 4 where the R31 GTS-R breaks the lap record - http://www.youtube.com/watch?v=BylbtOgkw4Q...feature=related Part 5 - http://www.youtube.com/watch?v=pXKciAZ1ZIs&feature=user Part 6 with Alan Grice passing the Cosworth in the R31 GTS-R - http://www.youtube.com/watch?v=mJ6jlHmySrI...feature=related

I noticed bigger diameter brakes help with pulling up cars that weigh alot. Look at the weight of the R35 GTR and weight of R34 GTR, R33 GTR, R32 GTR. You'll notice they weigh more with each generation and the brakes have bigger diameter rotors, bigger calipers (R35 GTR) to suit.

You're welcome. Engine probably would have idle problems when warming up, as blocking off hose to IACV valve is not allowing the extra air into intake plenum. Reading the thread and your post again, I think the sticky IACV valve could be part of the cold start up problem, but it seems you have replaced the AAC valve without resetting base idle on stock ECU and TPS could be incorrectly adjusted to the engines problems instead of the recommended factory voltage settings. So after you have fixed the problems, you'll probably need to readjust TPS to factory voltage settings. Also if base idle setting on ECU is set at 750rpm and screw on ACC valve is set at say 1100rpm, revs can bounce between those rpm's. Basically ECU adjusts idle to 750rpm and idle valve raises idle to 1100rpm. I guess it would explain why engine rpm drops to 1100rpm when deaccelerating. You can reset base idle on stock ECU with Nissan's Consult. Or another alternative is Datascan software, cable, which allows you to adjust the base idle, reset ECU, erase sensor error codes, etc. Datascan software, cable, etc - http://www.blazt.biz/?gclid=CMCD7rquoJECFRscawodbmIHOg Screen shot of software, "Base Idle Adjustment" feature - http://www.blazt.biz/products/images/datascanactivetest.JPG Burble or pop sound could be flames out the exhaust due to engine running rich. This could be from ECU running in kind of what you could could call a limp mode. I think ECU switches to the alternative low octane retarded ignition map, rich fuel map.

I have the same problem on my car and it's the IACV valve (cold idle valve) that needs cleaning because it's sticking. A way to avoid the stall is applying a little bit of throttle when starting the engine or crank the engine for a longer period. I noticed IACV valve replaces the choke on the dash of older 80's style Nissan's and is known as a automatic choke, that I think is controlled by ECU. The valve inside the IACV valve can stick due to being dirty or can't be repaired thus needs to be replaced. The IACV valve on the RB20DET is located on the bottom half of intake plenum, just behind the throttlebody. If you follow the rubber hose from AAC valve to J pipe that goes over the top of motor, you'll find a T section and the single hose from that T section leads to IACV valve. What you need to do is remove the IACV valve and spray down where the single hose connects to IACV valve and remove / clean out the built up dirt. Then check the movement of the valve inside the IACV valve with a flat head screw driver. If still sticky, then replace the IACV valve. Before refitting IACV valve, adjust the screw on IACV valve so the valve is fully open. Can't remember which direction it was. Basically how it works is IACV valve is fully open when engine is cold and slowly closes when the engine warms up. Once the engine is warm, ACC valve takes over to supply air to intake plenum. I think IACV valve adds extra air to intake plenum which combats the rich mixture in the cylinders when engine is warming up. Sometimes one or both of these valves can cause problems and need replacing. Other area's to look at with similar symptoms can be air leaks in intake piping, faulty or misadjust TPS and o2 sensor failure. I hope the above helps.

My advice would be to dyno the car and see at which boost level gives a safe A/F ratio when reaches near to boost at lower rpm's and at higher rpm's where turbo reaches full boost. It's better to pay $80-$100 to find a safe boost level than $2000+ for a new motor. With intercooler, dumppipe, bigger turbo upgrade it probably will require a low boost level for a safe A/F ratio. Maybe even invest in an adjustable HKS or Garrett actuator and adjust actuator arm, so the wastegate on back of turbo opens more, to help to lower the boost level. Or even fit a hose to actuator bulb with a GTR or S15 stock boost restrictor, which should help to drop the boost level.

There was a blue coloured R32 with stroked RB20 (RB24) that I have seen for sale in Japan (built for dragracing) that produced around 550ps. Here's what looks like another stroked RB20 in a 180sx with a huge T51R turbo and 600ps. Again the dyno's computer (laptop) has the dyno chart - http://www.youtube.com/watch?v=2PVE_im5l-M Also there's a white R32 GTS-T with series 2 front bumper (Australia) that produced around I think was roughly 319rwkw? with stock motor and roughly 358rwkw? with a strengthened motor, cams, etc at a dyno competition. It had RB25 gearbox, etc. Here's another RB20DET in a S14 that produced around 335rwkw (449.8rwhp) - I'm not 100% sure but I think that S14 dyno run was done in Australia.

Read the first paragraph - http://www.whiteline.com.au/swaybars.htm You're welcome.

Selby's swaybars (not sure if they make swaybars for Skylines) - http://www.hotfrog.com.au/Companies/Selbys-Swaybars K-MAC swaybars (As far as I know the prices on the website are in US dollars and they make swaybars for R32, R33, R34 in non adjustable and adjustable). K-MAC website - http://www.k-mac.com.au/ Swaybar prices - http://www.k-mac.com.au/pages/tuning/listofkits.htm Also I noticed they can custom make springs.

Thanks for sharing your thoughts on the subject GTST. I have seen in a magazine (from NZ) a higher flowing front mounted GTi-R intercooler with CA18 motor. I wonder if that's another solution for a stock turbo and R34 GT-T intercooler or will the piping be too long and affect response?? Limpus, That very long core length part baffles me when looking at the new R35 GTR which is used on the racetrack - http://image.blog.livedoor.jp/jdm_kumiko/i.../2/724e0858.jpg You'll notice in the photo above that the size of those cores are smallish but enough for engine to produce around 480ps (roughly 462hp SAE). As GTST has already said, smaller core seems to be better for response. But you'll also notice they are front mounted, which seems to give better flow. Trying to boost up a R35GTR with a simple exhaust upgrade seems to result in a 0.1 bar increase over the stock 0.8bar, as ECU seems to stop the boost from rising above 0.9bar. That is true about flow inside the core, as bar n plate and tube n fin cores affect the flow. Bar n plate is supposedly not as high flowing as tube n fin. Although in saying that, doesn't the HKS R33GTR dragcar run a bar n plate intercooler core with a 1500hp motor??? But that dragcar does have proper ducting for the intercooler, etc, similar to F1 racecars. Thanks FATAZZ for the alternative idea. There's also 2 styles of bigger louvers you can buy from ARC in Japan. I think they are made of aluminium. I guess just need access to a metal shop or hotrod shop and make your own louvers.

Thanks. Also Greddy, etc made some bigger upgraded sidemounts if you want one for R32, R33, R34. It's just finding a sidevent to vent the hot air behind stock or upgraded sidemount intercooler, to get the full cooling benefit of the stock intercooler or intercooler upgrade. It has to match contour of side of front bumper and size is important, as it needs to fit behind the intercooler. The only vents I have found are EVO side vents, 400R replica front bumper with the massive sidevents (I prefer the stronger plastic looking stock front bumper to fibreglass replica's).

Thanks for the kind words. This is what I have learnt from my reasearch (please don't quote me on this) - From my reasearch into the subject, cooling also comes from flow through the core, core length, pressure drop. FLOW THROUGH INTERCOOLER CORE The stock side mount on R32, R33 GTS has problems with removing the air behind intercooler due to small louver vent in the wheel arch. The result is hot air heat soaks the back of the intercooler core. On the R34 GT-T Nissan solved this problem with a sidevent (passenger side of front bumper), just behind the intercooler core. Here's a photo of a R34 GT-T and the side vent - http://digiads.com.au/carsales/used-cars/c...74.054981_1.jpg Also thickness of core plays a roll, as air touches the cooling fins on the outside of the intercooler core for a longer period of time. With a front mount intercooler you have the added benefit of the engine fan which helps to move air through the core. But the downside is heat soak from the intercooler core affects the radiator and watertemps. Also the aircon core on the R32, R33. R34 GTS and R32, R33, R34 GTR doesn't help as it blocks some of the air reaching the radiator. On the R31 GTS-R you'll notice Nissan moved the aircon core to the underside of car. I don't understand why they didn't do this with the later model GTS and GTR??? CORE LENGTH With core length the air has more time too cool down, which is where a front mount is worth it over the small length side mount for 100% percent throttle racetrack applications. Some say the cooling affect happens within the first few centimeters of the core length. CORE PRESSURE DROP Pressure drop affects how long the air stays inside the intercooler to be cooled. The ideal pressure drop is from what I remember, around 0.5-1.5 psi at a certain boost level. The stock sidemount intercooler provides this perfect pressure drop up until a certain boost pressure is reached. If pressure drop rises, it becomes a restriction and should be upgraded to a bigger size core. That's why 13.5psi (R32, R33 GTS), 14psi (R34GT-T) at 0.5-1.5 psi pressure drop with the stock sidemount intercooler and stock turbo sounds reasonable considering the size of core. I noticed the S15 side mount is good for 1bar (14.7psi) and has a similar size core to R34GT-T, but I think has a smaller T28 turbo. From what I remember there are size and CFM flow charts you can look at to decide on core size. Basically match turbo CFM at a certain boost level to intercooler core CFM at certain boost level. I guess the mismatch in CFM flow is why alot of cars that are fitted with big front mounts with stock turbo's are actually slower than the same car with a stock sidemount that is matched properly. Fitting a bigger turbo increases the CFM, so it makes perfect sense why the car performs better on the drag strip. Also does anybody know where to buy a side vent, like the R34GT-T side vent???

Limpus, At the moment I'm trying to achieve a higher power figure than a mates car with stock sidemount. I do know with front mount that I could achieve the same power figure but that would be too easy.

My comments are from other peoples experiences, experiments, comments on stock intercooler, etc and from my own reasearch into stock and upgraded intercoolers, etc and their applications.

If at 100% throttle constantly like on a racetrack, then yes you need a front mount intercooler. Also a steel wheel turbo upgrade. On the road, supposedly can get away with 20 second burst's with stock sidemount intercooler on a R33. A sightly larger R34GTT sidemount intercooler that's installed in a R32 GTS -T is said to be ok for couple of laps on a racetrack. I read that 13.5psi is the max boost for R32 intercooler. Isn't a coincidence that max boost on the stock R32, R33 boost gauge translates to roughly the same 13.5psi?? R34 GTT stock boost gauge roughly translates to around 14psi. Stock R32 GTS-T intercooler has been proven to be capable of around 211.3rwkw on a dyno at I think was 9.33psi with a RB25DET conversion in a R32 GTS-T. Here's the dynochart - http://img512.imageshack.us/my.php?image=dsc0725xw5.jpg Also add a bigger fuelpump to the ECU, intercooler upgrades.

It seems the stock ECU on your car has switched to the low octane fuel, ignition maps.

Adding a intercooler is going to lean out the A/F (Air/Fuel) ratio which creates more heat in the cylinders on top of the intake, exhaust mods that have already leaned out the A/F ratio and created more heat. Basically raising the boost level with intake, exhaust, intercooler, leans out the A/F ratio and is why a engine produces more power. The extra heat inside the cylinders is then transfered to the water running through the engine block and oil that lubricates the engine. Basically water and oil temps are going to rise. This is not good if your cars engine shares water and oil with turbo. With ECU your adjusting how much fuel is injected thus can help to stop the engine leaning out too much with intake and exhaust mods. Basically helps to keep cylinder temps under control.

Not sure what model of Skyline you have i.e GTS or GTR (I guess it's a RB20DET) and size of the turbo's like TD04, TD05, TD06, etc. But you should upgrade injectors, fuelpump and AFM + ECU when fitting a bigger turbo or when stock engine is boosted up to higher boost levels like above 14psi with stock turbo on say a RB20DET. Factory injector size should work ok with factory turbo (GTS) or turbo's (GTR) at mild boost levels. With RB20DET you might be able to fit intake, exhaust and maybe a bigger intercooler before exceding the safe A/F (Air/Fuel) ratio.

Because heat soak from engine bay heat causes the engine to lose power with a podfilter. There's a dyno chart on the internet somewhere (I think was done in Australia) showing the differences with bonnet up, down and with a coldairbox, etc. Engine gains 8 rwkw with bonnet up but when bonnet is down, engine power drops due to heat soak (hot air from radiator, etc). Some say this only happens when car is stationary like on a dyno. When a car is moving, alot of air is entering engine bay.The result is the engine bay cools down and water temps drop, etc. Basically a dyno fan is not producing enough air to properly simulate real world driving conditions. I guess can understand why ECU tuners take cars for a drive after dyno tune, so to check that the tune is correct for real world driving conditions. Another interesting thing I have found is water can enter between bonnet, fender and wet the podfilter (enter the intake piping, engine). With a cold air box fed by a intake pipe, this can be reduced. I can see why they put a airfilter in a airbox at factory, because it keeps the incoming air away from engine bay heat and water cannot enter intake piping, engine.