Air Intake Temps

[R31Nismoid]

I wasn't suggesting you were. We are using the same dyno's here on the east coast as the guys on the west.

To a point yes we are, the trap speed is not indicative of 280rwkw. Given even a mild variance for settings.

Further more the belief the turbo's cant make enough power for 10's (over 350rwkw) which has also been dispelled by Marko R1 in another thread

[R33GTRKid]

Ash,

I was saying on a stock bottom end motor, it would not be safe to push 350rwkw from SS's, not that it cannot be done.

I have left that point alone for some time now.

I am just racking my brains trying to work out why the car has 380 - 383 rwhp (two separate dynos confirm), I drove a pretty much flawless 1/4 and she only ran a 12.3 at 111 MPH (albeit the 60' at 1.82 seconds indicates the launch could have been better but I was running 18 265's and into a 24 kph headwind).

Many on here have suggested the trap speed indicates down on power, so I am trying to work out why, I thought the exposed pods and extended idling time while waiting to stage and run could have caused a reduction in power, hence me asking about the intake temps.

Can someone tell me how a CAI is installed on the 33 GTR. Looking at my front bar, where the left hand indicator is, there is a section of the plastic 'bar' type set up that is missing and a plastic channel/tube runs from there but I cannot work out where it runs to, but it definitely does not seem to outlet into the area of the engine bay where the pods are.

I will try to meet up with Rev210 to see how this can be improved BEFORE I go back to xspeed for the power tune.

Hopefully at the end of the day, once all this CAI and partition stuff is done, the car is tuned, I can run a low 11 at about 125ish MPH and all will be sorted and power matching trap speed (wishful thinking??)

[blow thru]

the only other thing I can think of then is a boost leak - on the dyno it hits 17psi at about 4,200 and holds to about 5,000 then tapers down to 15 and holds steady.

At the drags I did not see any higher than 15.5 at all.

So if 17psi was the 283rwkw, I guess the lower PSI (possible boost leak after tune) then explain the 110MPH trap speed?

what is involved in a proper workshop boost leak test - I mean getting told 'it will take a couple of hours of looking around the pipes' does not seem to be a very scientific way of doing it - I though you blocked off the turbo intake pipes or something and then pressure test the system using some form of tool?

BOOST LEAK TEST- take off air inlet,use your silicon hose joiner that goes on the front of the turbo an put a block in it.(i use a can of bog thats the same size)now take off a vacume line-i use fuel pressure line off intake manifold,use a compressor with an small hand air blower ,slide the vac line over the end of the air blower an fill the engine with air, this will show up all the leaks you will hear the air coming out.dont need to much air.It takes a matter of 5 mins.

[NickR33]

are you backing off before the finish line? maybe post your 330' 660' and 1000' times... the drag gurus should be able to tell you what's going on

[R33GTRKid]

nah she was planted, just shifted into 4th.

60: 1.805

330 5.077

660 7.905 at 141.08kph

1000: 10.295

1/4: 12.346 at 110.02 mph or 177.06kph

[blow thru]

nah she was planted, just shifted into 4th.

60: 1.805

330 5.077

660 7.905 at 141.08kph

1000: 10.295

1/4: 12.346 at 110.02 mph or 177.06kph

Its laying over in the deep end,on a working set up your mph should be around 25mph frm half track.do my boost test leak i told you.Its possible you loosing boost an when your shifting its taking to long to regain boost.Did you watch boost gauge frm pass to pass an did it vary? i had the same problem i run 1.5 bar an make 402rwhp on a rb20 an only went 108mph,watching gauge only go almost 1 bar an took to long for boost to recover hense low mph.Did my test an had a massive crack in my silicon elbow coming off the turbo,it burnt through frm heat on exhaust manifold.

[R33GTRKid]

what does 'laying over in the deep end mean'? not running hard in the latter stages of the 1/4?

actually now that you mention it, I was feeling a slight dead spot after the changes, like it went off boost completely and hesitated slightly (maybe half to one second) and then came back on so maybe I do have another leak somewhere.

Does that boost leak test work for a twin? I have the HKS racing chamber kit which replaces silicon from turbos to intercooler with hard piping but in saying that something else on that side may have given. I know that I have replaced all the clamps on the intercooler hoses as the bottom left one kept letting go and they are now holding good, which means other sections may have loosened.

The last few days I have also noticed a louder slightly different from usual intake/spool noise coming from the left side when I drove with windows down in a narrow street so I could be that on the strip I cracked a pipe or something and it is only a slight leak because I was still hitting about 15 psi. I also noticed this weekend that my boost seems to be coming on a little later, maybe 500rpm or so, so that is all now making me think there is a boost leak somewhere

Edited February 18, 2009 by R33GTRKid

[nIsMo86]

Can someone tell me how a CAI is installed on the 33 GTR.

Ok i cant tell you how to do a CAI on 33 GTR exactly but i'm sure its similar to a 32. Heres pics of what i did...note that the pod is enclosed in a custom airbox aswell.

I enlarged a hole that was already underneath my pod to approx 100mm in size. Fitted a rubber seal to the exposed metal. Fitted a 100mm PVC elbow joiner in the hole (Fits very snugly). Sprayed it black. Fitted some 100mm household flexible exhaust fan ducting to the pipe and then joined to inlet hole on my front bar. Gained 14kw atw on my following dyno run and also gives much better top end and obviously cooler intake temps. Have since modified my front bar inlet to a sealed duct that goes from the size of inlet hole and tapers in to 100mm but havent got pics or dynoed as yet.

Heres the pics..

Sorry bout the bad quality of pics. Hope that helps give you an idea of what to do.

[blow thru]

what does 'laying over in the deep end mean'? not running hard in the latter stages of the 1/4?

actually now that you mention it, I was feeling a slight dead spot after the changes, like it went off boost completely and hesitated slightly (maybe half to one second) and then came back on so maybe I do have another leak somewhere.

Does that boost leak test work for a twin? I have the HKS racing chamber kit which replaces silicon from turbos to intercooler with hard piping but in saying that something else on that side may have given. I know that I have replaced all the clamps on the intercooler hoses as the bottom left one kept letting go and they are now holding good, which means other sections may have loosened.

The last few days I have also noticed a louder slightly different from usual intake/spool noise coming from the left side when I drove with windows down in a narrow street so I could be that on the strip I cracked a pipe or something and it is only a slight leak because I was still hitting about 15 psi. I also noticed this weekend that my boost seems to be coming on a little later, maybe 500rpm or so, so that is all now making me think there is a boost leak somewhere

Laying over means loosing power or stops making power,an for deep end yeah after 1/2 track

on ya twins take off ya pod filters an get 2 peices silicon hoses an block them wherever you can then you will be able to do this test.This will show any vac leaks which is costing you boost an power.If your engine is mapped for a certain boost setting an the engine is not seeing that desired boost you possibly will foul up ya plugs.As for your noise ya hearing it sounds a definate boost leak.let me no how you go..

[R33GTRKid]

nice one, ill go the boost leak test asap

and thanks Nismo 86, I do not think there is any hole on mine where yours has one, but will check it out and see what I can make, I must admit, it seems the obvious way of doing it.

[Dan_J]

does the gtr only have a air temp sensor or did da gtst have one and if so where's it at

[SLAPS]

32 GTR has the IAT in the plenum the 33 I believe has it in the IC piping towards the front of the car to prevent heatsoak. Unsure of its exact location.

I have mine located in the inner bumpers IC piping.

I find the std IAT sensor to be quite slow reacting. Would be nice if there was a replacement that were considerably quicker. I've looked at the GM IAT's but they are way off.

The GTR IAT definitely modifies ignition and from memory fuel also. Its been a while since I hooked the datalogit up to it.

Edited February 19, 2009 by TheRogue

[Adriano]

33 gtr's have them in the same location as 32gtr's. 34's have them in the intercooler end tank. PFC's may have a fuel comp tanle, but i dont think so, stock ecu definately doesn't effect fueling, only ignition, and only over 70 deg inlet temps.

[Dearlove]

why dont you do another day down at the strip??

that way you can eliminate the head wind, and temp issue?

what does 'laying over in the deep end mean'? not running hard in the latter stages of the 1/4?

actually now that you mention it, I was feeling a slight dead spot after the changes, like it went off boost completely and hesitated slightly (maybe half to one second) and then came back on so maybe I do have another leak somewhere.

Does that boost leak test work for a twin? I have the HKS racing chamber kit which replaces silicon from turbos to intercooler with hard piping but in saying that something else on that side may have given. I know that I have replaced all the clamps on the intercooler hoses as the bottom left one kept letting go and they are now holding good, which means other sections may have loosened.

The last few days I have also noticed a louder slightly different from usual intake/spool noise coming from the left side when I drove with windows down in a narrow street so I could be that on the strip I cracked a pipe or something and it is only a slight leak because I was still hitting about 15 psi. I also noticed this weekend that my boost seems to be coming on a little later, maybe 500rpm or so, so that is all now making me think there is a boost leak somewhere

[R33GTRKid]

found a cracked IC pipe, IC 2x in and 2x out hardpipe kit going in and final tune on Thursday, plex next Wednesday, see if I can build a partition on long weekend too

[PM-R33]

does the gtr only have a air temp sensor or did da gtst have one and if so where's it at

Only RB26's have them standard, RB25's don't and im pretty sure neither do RB20's.

I installed a universal one just after the filter, that way i have exact intake temps into the turbo, not after what the intercooler has cooled.

[Dan_J]

would be more useful if you had it after the intercooler so it tell's you how well its cooling in hot days etc but there useful none the less