RHD RB30 Build - update 6/20/13

Discuss the RB20, RB25 and RB26 series engines.
J2fast
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Booztd 3 wrote:Well where is the air going?

The way the boost leak test works is that it seals on either the back of the intake valves, or the front of the exhaust valves. Air always coming out the exhaust indicates a problem with an exhaust valve for example. Also pull your dipstick when you're doing the test and see if you've got a bunch of air coming out the crankcase. If you can't build any pressure and there's no boost leak connection (coupler, clamp, etc) thats noticeable then I'd start looking into the engine.
hhhhmmm.... not that im jumping to conclusions but trying to see worse case, you think the head could be something wrong in there? but im going to redo all air lines and retest it and make sure 50 more times before taking it apart but its crasy that it cant even go past 1 psi on the tester but it can hold 20 psi on the street.


Booztd 3
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J2fast wrote:
Booztd 3 wrote:Well where is the air going?

The way the boost leak test works is that it seals on either the back of the intake valves, or the front of the exhaust valves. Air always coming out the exhaust indicates a problem with an exhaust valve for example. Also pull your dipstick when you're doing the test and see if you've got a bunch of air coming out the crankcase. If you can't build any pressure and there's no boost leak connection (coupler, clamp, etc) thats noticeable then I'd start looking into the engine.
hhhhmmm.... not that im jumping to conclusions but trying to see worse case, you think the head could be something wrong in there? but im going to redo all air lines and retest it and make sure 50 more times before taking it apart but its crasy that it cant even go past 1 psi on the tester but it can hold 20 psi on the street.
Well, like i said - The air you're pumping into it with a compressor has to be going somewhere. What is the regulator on your compressor set to? I never dial it down I just keep it turned up.

How much more than 20psi does it hold on the street? Loading on the dyno and loading on the street are almost never the same so I can see a delta existing between the two.

I dont want you to jump to conclusions either, or get worried that there's an issue with your engine. However, anytime I've ever boost leak tested an engine, even the smallest leaks were VERY evident to the ear. They may have been a pain in the a** to get to, but they were very easy to hear.

RRRRB
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What cams are you using.. bigger cams tend to have more overlap.. which means both valves are open.. try manually rotating the engine over with he tester attached.. if you have cam gears dial overlap out..

J2fast
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Well, like i said - The air you're pumping into it with a compressor has to be going somewhere. What is the regulator on your compressor set to? I never dial it down I just keep it turned up.

How much more than 20psi does it hold on the street? Loading on the dyno and loading on the street are almost never the same so I can see a delta existing between the two.

I dont want you to jump to conclusions either, or get worried that there's an issue with your engine. However, anytime I've ever boost leak tested an engine, even the smallest leaks were VERY evident to the ear. They may have been a pain in the a** to get to, but they were very easy to hear.[/quote]

well i was thinking about that cuz now that i think back on it the compressor line had a couple of holes and the air nossle was leaking thru the side but not sure if that would effect the testing either???

on the streets just wastegate is 20psi on dyno with WG is 15psi but cant get it to get higher than 26psi on the street and 24psi on dyno.

i have 272 cams with 10.5 lift. the shims are kinda worn cuz the cam lope is not there and you can hear them pretty good.(dontknow if that matters)

J2fast
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so i found some good news, i had a really big leak coming from the boost controller solenoid. it had came apart and was leaking the air out of it. screwed back up and cant hear any more air. and i have a intercooler pipe that is not 100% circle which is letting air out. im glad its only something that small, SO FAR...

my next thing is fixing the lifters, i need to re shim those, yall think thats alot of power lost?

Booztd 3
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What boost control solenoid?

A lot of 3 port solenoids simply vent one port to atmosphere

J2fast
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Booztd 3 wrote:What boost control solenoid?

A lot of 3 port solenoids simply vent one port to atmosphere
i have the hks evc 5, which does have 3 ports.

RRRRB
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i don't think it would cause any noticeable power loss, however that stuff doesn't normally come out of adjustment very quickly.. I would check clearance with a feeler gauge first to verify thats the noise, my injectors tick quite noticeably on my rb26 headed rb25 so make sure its the valves first.

Also how much do you have the oil restricted to the head..

J2fast
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RRRRB wrote:i don't think it would cause any noticeable power loss, however that stuff doesn't normally come out of adjustment very quickly.. I would check clearance with a feeler gauge first to verify thats the noise, my injectors tick quite noticeably on my rb26 headed rb25 so make sure its the valves first.

Also how much do you have the oil restricted to the head..
well my engine builder told me tha htere were atleast 4 lashes that are way off when he put it together but at the time i couldnt get big enough shims.so i know thats the case as far as that goes. but as far as power goes i have no idea. but the lashes or so off you cant tell that i have big cams in the car at all...

RRRRB
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sounds like you have a mess on your hands bud, i wouldnt have ran that thing without proper lash set in the first place... what base circle size are the cams.. what lifter buckets are in it and what retainers are you using? id talk to supertech about shims, i have there lightweight buckets and shim setup in my 26 head i'm using 260 10.25 cams

RRRRB
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id suggest these, with the appropriate pad size

http://www.rawbrokerage.com/supertech-c ... -rb26dett/

J2fast
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RRRRB wrote:id suggest these, with the appropriate pad size

http://www.rawbrokerage.com/supertech-c ... -rb26dett/
Yea that's what I was going to order.

J2fast
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So an update. I purchased am Aem ecu even though I really wanted haltech but I got it at an unreal deal. So that should be coming

J2fast
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just wanted to pick yall brains a lil bit. so i did the Q45 diff swap and every since then my rpms and speedo are off. the rpms seems good until you get pasted 6-7k rpms and the speedo is good until you get over 50 mph. is there anyway to correct this?

RRRRB
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http://www.yellr.com/yb_home.htm

Dakota digital makes something simular as well

J2fast
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RRRRB wrote:http://www.yellr.com/yb_home.htm

Dakota digital makes something simular as well
thanks that looks real good, what about the rpms

RRRRB
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S14's have an adjustment screw on the back of the tachometer, i used my engine managment as a reference and adjusted the screw until it read as close as i could read it.

J2fast
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RRRRB wrote:S14's have an adjustment screw on the back of the tachometer, i used my engine managment as a reference and adjusted the screw until it read as close as i could read it.
OH OK. the only issue i see is it works until about 6000 rpms then it goes crazy.

Darius
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The tach signal is an output from the ECU and an input to the gauge cluster. Changing the drive train will have no effect on it. Are you sure your CAS is working properly? Like others have said, there is an adjustment that can be made to the stock cluster or you can buy the Dakota digital converter (route I chose).

J2fast
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Darius wrote:The tach signal is an output from the ECU and an input to the gauge cluster. Changing the drive train will have no effect on it. Are you sure your CAS is working properly? Like others have said, there is an adjustment that can be made to the stock cluster or you can buy the Dakota digital converter (route I chose).
Well my ecu reads the correct Rpms which had me thinking but I didn't know it was just from the ecu only

Darius
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Does the ecu ever show the rpms freaking out or is it just the gauge cluster? Does the engine studder or act weird or is it solely the gauge cluster that acts up?

J2fast
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Darius wrote:Does the ecu ever show the rpms freaking out or is it just the gauge cluster? Does the engine studder or act weird or is it solely the gauge cluster that acts up?
Yes it's just the cluster. I noticed it only cuz I was on the dyno n seen it go way passed 8k n I know I set the rev limiter to 7600 but the ecu said it only went 7k n also the dyno as well

J2fast
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so i finished the boost leak test and i have no leaks and i still have the same issue, cant boost over 20 psi. i even disconnecteed the boost controller hooked directly from intake mani to top of the wastegate and still only get 15-18psi. do you think it can be the wastegate? ive changed springs added more springs and i get the same result. i had a few major boost leaks and fix them and i get the same number. im lost.

RRRRB
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perhaps the turbine housing or compressor housing is a missmatch iv'e actually had that happen to me... i got a 30R with a 35R turbine housing

J2fast
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RRRRB wrote:perhaps the turbine housing or compressor housing is a missmatch iv'e actually had that happen to me... i got a 30R with a 35R turbine housing
Really that will stop it from boosting alot? I got it from comp turbo with the housings.

godzilla_753
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Didnt read the entire thread, but I would recommend a leakdown test/compression test at this point. You are obviously losing air pressure somewhere. Either it is not being made by the turbo, meaning theres something wrong there. Or you've got a leak somewhere, and you've already done the boost leak test and its not leaking from the obvious places. The leakdown test will show you if its the valves/rings/headgasket etc which would need engine rebuilding. Good luck man!

J2fast
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godzilla_753 wrote:Didnt read the entire thread, but I would recommend a leakdown test/compression test at this point. You are obviously losing air pressure somewhere. Either it is not being made by the turbo, meaning theres something wrong there. Or you've got a leak somewhere, and you've already done the boost leak test and its not leaking from the obvious places. The leakdown test will show you if its the valves/rings/headgasket etc which would need engine rebuilding. Good luck man!
dang thats gonna suck. just some more info on some testing ive done, so ive been messing around with the boost controller an i turned it all the way up as high as it would go and 1 out of 4 runs i go the wastegate to open loud enough to hear which it hit 25 psi that run the rest were like 18-21psi . any thoughts to that?

RRRRB
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I think you have a turbo issue... I mean you got lots of boost prior to this turbo with reasonable boost controller duty right.. all you changed was the turbo?

I've heard horror stories about comp turbochargers.. I'd pull it and look closely at the housings and how they fit..

If the engine is running fine it isn't the cause..

J2fast
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RRRRB wrote:I think you have a turbo issue... I mean you got lots of boost prior to this turbo with reasonable boost controller duty right.. all you changed was the turbo?

I've heard horror stories about comp turbochargers.. I'd pull it and look closely at the housings and how they fit..

If the engine is running fine it isn't the cause..
well i started having this issue before this turbo. on the last one on wastegate pressue it would boost to 25psi but i started having issues with the turbo and thought it was that. then i get this turbo and cant fix it.

J2fast
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well i have did all the engine tests and all looks good (compressions and leak down) i even made sure it wasnt my new intercooler im getting about 2.5 psi pressure drop. i even switched out the springs again to only get the same answer. im starting to think maybe the boost controller solenoid is bad but idk what kinda problems that would lead me to. but it pulls super hard on 25psi prob harder than with the other turbo at 29-32 psi. but something will not allow it to go higher than 25-26 psi. any thoughts?


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