GT72 turbo kit and HKS 264 cams....Low idling???

[SupraClaou]

Just installed the 264 HKS cams. With BC springs and retainers. Also some
Greddy cam gears with Greddy pulleys. I had the car in the shop for 14
days and the battery died...
I first started the car some hours ago and I had high idling 1.400 rpm
for 3 minutes and after it's warm up session it came down to 650-700 rpm.
Low idling...? Why ? And some times it makes a loop down to 500 and occasionaly dies.
Usually they say that you gain some rpms and not losing from installing 264 cams
with a stock oem ecu.

The only thing I can think about is that the ecu was reseted after
the addition of the cams,and it may take some time to make the
correct adjustments.

And my A/F is 13.0 / 1 during idling...... Maybe I am so sich in fuel that
I f''''''ed up my idle

 

[tissimo]

Stock ecu wants to idle ~ 600 or so rpms

 

[zoppii]

Mine did the same thing, but in stages. I started with a 650 rpm idle nice and steady.

1st I installed my HKS 264's cams with the gears set at 0 and my car would barely idle. I cleaned and checked my ISC valve and gapped my TPS just to make sure and then eventually just raised the idle slightly with the set screw back to about 650. A/F's were at 14.9 +/- .3 on fluctuation. I ran like that for a couple of years with no issues.

About a month ago I upgraded my turbo and manifold from a CT26 with the DM 1J adapter manifold to a Turbonetics T4/T61 turbo along with a new manifold and supporting stuff and now my A/F's are at like 13.1 at idle but I've managed to get a nice 11.0 at WOT with a little adjustment through the SAFC. I didn't want to turn down the fuel pressure to compensate for the idle A/F's and sacrifice the needed pressure at WOT.

Based on this I would have to guess that the idle speed difference is due to the Cams and the A/F change is due to the turbo upgrade/cam combo.

Bottom line is that it sounds like we both need a standalone to get it dialed in to perfection. It's on my list but for now I'll just have to deal with a slightly rich idle until I recover from all the money spent on the Turbo upgrade.

 

[SupraClaou]

Mine did the same thing, but in stages. I started with a 650 rpm idle nice and steady.

1st I installed my HKS 264's cams with the gears set at 0 and my car would barely idle. I cleaned and checked my ISC valve and gapped my TPS just to make sure and then eventually just raised the idle slightly with the set screw back to about 650. A/F's were at 14.9 +/- .3 on fluctuation. I ran like that for a couple of years with no issues.

About a month ago I upgraded my turbo and manifold from a CT26 with the DM 1J adapter manifold to a Turbonetics T4/T61 turbo along with a new manifold and supporting stuff and now my A/F's are at like 13.1 at idle but I've managed to get a nice 11.0 at WOT with a little adjustment through the SAFC. I didn't want to turn down the fuel pressure to compensate for the idle A/F's and sacrifice the needed pressure at WOT.

Based on this I would have to guess that the idle speed difference is due to the Cams and the A/F change is due to the turbo upgrade/cam combo.

Bottom line is that it sounds like we both need a standalone to get it dialed in to perfection. It's on my list but for now I'll just have to deal with a slightly rich idle until I recover from all the money spent on the Turbo upgrade.

Same thing bro. I have a motec already to install. But I need some money
for the tuning and 2-3 other small parts like twin Sard (denso) pumps etc.
But I need to recover from all the money I've spent till now also.

CAN I set - paly with the intake cam to adjust the idle a little bit?
I have Greddy pulleys and I can tune them a little bit.

 

[zoppii]

I wouldn't mess with any of that until you can get it tuned. Actually, I talked to a well known tuner here in Florida who has tuned many JZ engines in the 1,000 hp range and he said his experience with the HKS cams is that they are so well made that he rarely has to adjust the gears from nominal and if he did it would only be his last step in tuning. He said the amount of performance enhancement you gain from it is minimal if any at all after a good tune. I would just up the idle with the set screw. You can always change it back later and will end up setting your idle speed with the Motech anyway once you get it installed.

 

[OneJArpus]

from what i hear, when the car is warmed up adjust the idle to 1K. With cams you should not be below that. BUT thats only from what i hear

 

[soapra]

When you install any aftermarket cam, you need to adjust the valve clearance and also degree the cams. Because of the added lift it will affect idle if the valve clearance are off and also if the cams are not degree.

 

[tissimo]

IF you're having problems with the low idle and dont want it. Start the car cold ( should idle ~ 800 or so, then unplug the ISC. It'll keep its low idle setting and probably idle ~ 1000 warm. That or crack the Throttle with the set screw through the ECU will try to fight you.