mabru

Yeah Bbenny, I've given up for now as well, no amount of SAFC tweaking gave me an idle above stalling. I've already got the RB20 cams bolted back in now, I'll finish up in the morning and hopefully be none worse for wear. I'm sick of my car doing it's imitation of a statue! I'm thinking that the 4 degree retard on the exhaust cam that SK recommended would make a hell of a difference. -Matt

I did try it at first, but this whole cam issue has forced me to track down a couple problems that were pre-existing so I've gotten sidetracked a bit. The AFM plug was having intermittent contact and the water temp sensor was stuffed. I've taken care of these two issues and now I can back on track again, I'm going to try and adjust the AAC after work this evening. As I posted earlier, leaning out the SAFC on the low RPM/low throttle made the car feel better but the idle was really really weak, to the point it would stumble and die off after a few minutes. I'll give the AAC another go and see if I can coax it up a bit. -Matt

Nah Benny, same stuff so far, idles really really low then croaks. I am going to try and adjust the idle speed a bit when I get some more time to look at it and tweak the low settings a bit. Once in a while it will idle, but it's not very common yet. I'll work it out but it takes time I guess. I promised a friend I'd do his auto-manual conversion tomorrow so there goes a chunk of my troubleshooting time! -Matt

I managed to throw the engine back together this morning and had just enough time before work to do some SAFC tweaks. After leaning it at low RPM quite a bit it has better, smoother throttle response. I still can't get it to idle above a couple hundred rpm. I need to find a way to get the idle speed up on the stupid thing, if I could manage to get to about 950 or so RPM I would be home free I think. Can you tweak the idle settings with the ignition on without having the car idling already? Thanks, -Matt

I am currently running an SAFC II, so I'll give the low RPM low throttle settings a little tweak and see how it runs after. SK- I was basically grasping at straws with the whole torque settings thing since I was running out of ideas. I'm guessing the extra lift has put the lean/rich condition over the top and the ECU can't keep up. -Matt

My cam probs are on temporary hold, I'm in the middle of my work days at the moment so time for car repair is virtually non-existant. I'll start my break on Sunday, doing a friends auto > manual conversion that day then hopefully I can sort my probs out after. I am anxiously awaiting more info from Bbenny though -Matt

Ok, I'm wondering if I should be using a different torque spec for the cam retaining bolts other than whats listed in the R32 engine shop manual. I'm starting to think that maybe the clearances are too tight and it's causing the low rpm problems. SK, what torque setting do you guys use when doing this swap? I'm just about out of ideas. Thanks for any input, not trying to hijack your thread Bbenny, just trying to achieve the same end result -Matt

Yeah I've run the gun on it, but with no steady idle to speak of it's pretty hard to get a decent reading. It bounces between 20 and 30 degrees BTDC near 1000 rpm. I have attempted to adjust the CAS with almost no positive results. I might be forced to put the stockers back in just to make sure everything is ok in there. -Matt

Ok, swapped in a good water temp sensor and that didn't help much. I'm starting to think it's the brackets of the cam's themselves, ie. not enough clearance compared to the stock RB20 cams. My engine sounds like its laboring pretty hard to idle and runs ok above 3k rpm. At first I thought maybe I had put the timing belt on too tight but I've redone it and seems fine, there isn't much left for me to check at this point but the cam's and/or the bearing clearances. -Matt

Hi Benny, I just finished my cam swap as well this past week and the car has been down since with the exact same problem you are describing. The timing marks are dead on, all 6 plugs are getting spark, and there's PLENTY of fuel, I know this because the plugs almost instantly foul after a couple attempts at idle. I have noticed that when it is colder outside the car will idle until it warms up a bit, my ECU is now pointing the finger at the coolant temp sensor. I have also performed a comp check of all 6 cylinders and they all read the same value, I am under the assumption that if there are bent valves then the comp gauge should not hold pressure (I could be wrong, it's happened before). Of course if I have valves bent in one cylinder then somehow I have valves bent in all six and I think I would've noticed something, a noise perhaps. I have checked everything I can think of at this point and have been using my wife's S14 as a taxi lately. I have ohmed out the harnesses to the AFM, swapped AFM's, CAS's, and ignitors with a friend's known good parts. But I am so glad someone else has performed this swap and seen the exact same problem as I have. You are not alone... I'm going to replace my coolant temp sensor tonight after work and see if it makes it better, my car has idled exactly 3 times since the swap and everytime its been after it was a chilly rainy evening. I'll re-post after I check out this temp sensor issue, hopefully with some positive results. Of course any other ideas/suggestions are appreciated -Matt

I am running the standard ECU. The cams are RB26 cams so yes, they have more lift and very little change in duration. -Matt

Quick update (and shameless bump), the ECU has finally spit out an error code, it points to the water temp sensor. I'm not exactly sure a water temp sensor will cause my problems but I'll swap it out and keep checking. -Matt

I know it has to be something stupid, we performed a cam swap and of course had to remove several vacuum lines and sensor harnesses to tear down the top end. After the swap I get no idle and plug fouling on all 6. I'll recheck fuel pressure and look at the air reg and do some more component swaps. Thanks, -Matt

I'm just about stumped. I have timing set at the proper marks, I have spark at all six plugs, and I definately have fuel. The ECU is reading a '55' on every diagnostic, my ignitor, my afm, and my CAS work in my friends RB20DET just fine. I have cleaned out the AAC valve and can't find any vacuum leaks. The only indications I get of any problems are that my car will not idle higher than a few hundred RPM and all 6 of my plugs foul up really quick. I have checked the ignition and CAS harnesses from the ECU and they check out good, so no breaks in the harnesses. I'm starting to grasp at straws, I'm going to ohm out the AFM harness in the morning and work from there. Has anyone ever seen anything like this before? I'm going nuts. Thanks for any input, -Matt

Yeah I figured the idle will have to be set at approx 950rpm, the GTR idle is supposed to be 950 per the shop manual, it was pretty lumpy at 650rpm. As for the performance gain, I'll know more when I get it working again. I don't have any time to work on it for the next 2 days, I work 12 hour days and don't get off until the nighttime. I'll post some more detailed info after I get it up and running again.

It was fairly straightforward, ie. no different than any other cam swap. I'll feel more comfortable writing a DIY after i get the thing idling again! Basically remove the top of the engine, all accessory belts, crank pully, radiator/shroud/fan, timing belt, and in my case intercooler cross pipe. I'll write an in-depth after i sort everything out. -Matt Oh yeah, of course remove cams and cam gears! :Oops:

Ok, long story, so here I go: I did the RB26 cam swap into the 'ol RB20 this weekend, and drove the beast home, the car would not idle anymore after this. I also popped an intercooler pipe coupler on the drive home. After parking it in the driveway and after some intense study I noticed the exhaust cam wheel slipped a tooth while we were installing the timing belt. I ripped it apart again and lined up the timing marks properly. The car still won't idle now, I have performed the following checks to eliminate possible problems since most of the top end was off the block to perform the swap: ensured the timing is per factory spec, swapped out the afm with a known good afm (buddy also drives an r32), swapped ignition amp with known good, run a comp check on all 6 cylinders, cleaned out the AAC valve, and attempted to adjust idle speed. At the moment the car wont idle, runs well above 900-1k rpm and above, and the spark plugs are sooty as hell (they weren't before the cam swap). I'm thinking that when the int. pipe was off and the timing was off during the drive home the plugs became really fouled and hopefully a plug swap will help it out. I'm also leaning towards the possibility that a harness got screwed up during all the tear-down/rebuilding. Any other ideas will be greatly appreciated Thanks, -Matt

The pressure plate dimensions are the same and I installed a new release bearing. I will try and re-bleed the system and see if I can get any air out of that little clutch line junction box. I'm just getting sick of brake fluid! I can't stand the smell! Thanks much, -Matt

Hopefully someone can help me out. I've recently upgraded my R32 to a Cusco Metal clutch, I also purchased the Cusco HD Pressure Plate. No matter what I do I cannot get enough pressure to use the pressure plate, ie. it will not disengage. It gets real close but it just wont release. So far I've replaced my clutch master cylinder since it was leaking around the piston seal, I've bled the lines out, and triple checked for any leaks with no luck. I can't figure what it is, I'm leaning towards a different pivot ball or clutch fork so I can change the pivot point. Any ideas? Thanks, -Matt

Does anyone know what a/r's the stock RB20DET turbine and the VG30 turbine are? Thanks, -Matt

I've heard that about the NA cams as well, I was originally after just the cams but I figured since he's parting out the beast I may as well snatch the whole head Thanks again

Are the cylinder heads of the RB20DE and the RB20DET the same physically, i.e. combustion chamber sizes, valve sizes, and cooling/oil passages? I have the chance to get a NA head to mess around with and want to make sure it's not that different. Thanks, -Mabru