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Delta Cam Questions

413K views 2K replies 287 participants last post by  Captain Kirk 
#1 · (Edited by Moderator)
For those who have installed these cams are you happy with the performance upgrades? How much better responce did you get? Is it difficult to shim? How did it effect your fuel milage?
 
#204 ·
The sohc do have roller rockers.

All the delta cams are that way, as well as twe from what I hear. This is normal, it does make it alittle harder to adjust the lash since it seems to grab the feeler guage, and they will make more noise than normal but will work fine. My delta cams have been in for 15 or 20k miles rechecking valve lash 3 times inbetween (no adjustments needed and no abnormal wear).

If you don't have them already the el header w/no or hfc makes a huge difference the the cams.
 
#205 · (Edited)
Cams installed ~ engine buttoned up!

00rs said:
The sohc do have roller rockers.

All the delta cams are that way, as well as twe from what I hear. This is normal, it does make it alittle harder to adjust the lash since it seems to grab the feeler guage, and they will make more noise than normal but will work fine. My delta cams have been in for 15 or 20k miles rechecking valve lash 3 times inbetween (no adjustments needed and no abnormal wear).

If you don't have them already the el header w/no or hfc makes a huge difference the the cams.
OK. Listen up. 00rs is right. The connection of the tappet to valve stem IS angled, but it is still hitting close to dead center, we got in there with a light and magnification (photo ~ you got to be kidding!).

Picture this: > That is the angle between the tappet/rocker arm and the bottom of the valve stem with the new geometry. But, it still hits the flat spot on the bottom of the valve...

I had three Suby techs (each with 20 years + as certified Subaru techs) on the conference call. After almost 1/2 hour on the phone with Scott (Delta) they were convinced on Scott's comments and approach to higher lift and longer duration were dead on and the comments we got from past customers confirmed 'no issues'.

So, we finished the job and 'buttoned 'er up'. The valve train noise is NO more then OEM. Factory valve settings are 8 & 10, Delta suggest 6 & 8 and we went with 7 & 9 (based on Cobb's recommendation). Also, run a 1,000 mile break in with REAL oil... then you can switch back to synthetic.

BUT ~ Now, this is the problem. Idle.

I knew we would be 'lumpy' (It always has been with a 'performance cam'). But, the damn car would idle perfect @ 900-1000 RPM if we could 'set' the idle. However, the ECM wants to idle it at 400 RPM (please give me 'old school with a simple 'idle screw' ~ why does something sooo easy have to be so hard?).

At least 30% of the time it now stalls at a stop. Now, the '07 ECM (factory) is the 1st to have 'idle control' and lets the tech set any idle speed between 0 - 2000 rpms. but this won't work on any non-variable valve timed car.

So, you people with Deltas ~ how did you kick up the idle on your car?

PS: DJ, the cores are coming to you, I don't feel there are any worries about the install and longevity of the valve train. I spoke to several happy customers (count 00rs in as well).

But, we DO need to put our heads together and come up with a way to increase the idle RPMs. BTW- The car seems MUCH stronger pulling to high RPMs... but I am not going to stand on it hard till I have a couple hundred miles on the clock.

To get this done right and to try and pave the way for the rest of you, I spent 12+ hrs of labor on this. Someone else needs to get a 'base line' and an 'after' pull on a dyno, I am tapped out $$$! :blowingup
 
#517 ·
OK. Listen up. 00rs is right. The connection of the tappet to valve stem IS angled, but it is still hitting close to dead center, we got in there with a light and magnification (photo ~ you got to be kidding!).

Picture this: > That is the angle between the tappet/rocker arm and the bottom of the valve stem with the new geometry. But, it still hits the flat spot on the bottom of the valve...

I had three Suby techs (each with 20 years + as certified Subaru techs) on the conference call. After almost 1/2 hour on the phone with Scott (Delta) they were convinced on Scott's comments and approach to higher lift and longer duration were dead on and the comments we got from past customers confirmed 'no issues'.

So, we finished the job and 'buttoned 'er up'. The valve train noise is NO more then OEM. Factory valve settings are 8 & 10, Delta suggest 6 & 8 and we went with 7 & 9 (based on Cobb's recommendation). Also, run a 1,000 mile break in with REAL oil... then you can switch back to synthetic.

BUT ~ Now, this is the problem. Idle.

I knew we would be 'lumpy' (It always has been with a 'performance cam'). But, the damn car would idle perfect @ 900-1000 RPM if we could 'set' the idle. However, the ECM wants to idle it at 400 RPM (please give me 'old school with a simple 'idle screw' ~ why does something sooo easy have to be so hard?).

At least 30% of the time it now stalls at a stop. Now, the '07 ECM (factory) is the 1st to have 'idle control' and lets the tech set any idle speed between 0 - 2000 rpms. but this won't work on any non-variable valve timed car.

So, you people with Deltas ~ how did you kick up the idle on your car?

PS: DJ, the cores are coming to you, I don't feel there are any worries about the install and longevity of the valve train. I spoke to several happy customers (count 00rs in as well).

But, we DO need to put our heads together and come up with a way to increase the idle RPMs. BTW- The car seems MUCH stronger pulling to high RPMs... but I am not going to stand on it hard till I have a couple hundred miles on the clock.

To get this done right and to try and pave the way for the rest of you, I spent 12+ hrs of labor on this. Someone else needs to get a 'base line' and an 'after' pull on a dyno, I am tapped out $$$! :blowingup
When you talk about "valve settings" what is that exactly? I am very interested in doing this and will prolly do it with a friend of mine. Can this be done by an "intermediate" who knows a little or should I have it done professionally?
 
#207 ·
ej25power said:
Your throttle doesn't have the adjustment screw? Kinda weak.

Thanks for the write up though.

When I get a job, I'll look into getting a "baseline", or if someone beats me to it, I won't.
:stupid:

Weak? Hello...

'05 is Fly By Wire... nothing to adjust. All up to the 'brain' which at this point I am willing to call 'retarded'! I am sitting with 60 years of Subaru technician expierence. You think we REALLY missed an "adjustment screw"?

Go grab some milk and cookies and check back in tomorrow morning! :loser:
 
#209 ·
You can't just crank in the little screw on the TB anyway...that's how you fuck up the idle real quick. The ECU will fight the sensors and you'll have a constant searching idle up and down.

The SSM used to have the capability to adjust the idle values...did the techs look into that? The only way I was able to consistantly bump the idle on any of my motors was to bypass the coolant going through the IAC. Not all years have this, so YMMV.

What about vacuum? Can you reroute some lines to see if any changes are made in the idle?
 
#211 ·
Storm said:
You can't just crank in the little screw on the TB anyway...that's how you fuck up the idle real quick. The ECU will fight the sensors and you'll have a constant searching idle up and down.

The SSM used to have the capability to adjust the idle values...did the techs look into that? The only way I was able to consistantly bump the idle on any of my motors was to bypass the coolant going through the IAC. Not all years have this, so YMMV.

What about vacuum? Can you reroute some lines to see if any changes are made in the idle?
Thanks for the clues ~ I will pass this on and we will see what we can do!
 
#212 ·
I guess I should mention, that anyone with an older car then '05 should have no issues with bumping up the throttle speed by adjusting the the throttle cable. Lucky me.... :letitout:

Wow! Look, I am over 1K post ~ when did that happen?
 
#216 ·
ej25power said:
Sooo, can you or can't you adjust the throttle by adjustin the screw on the TB?

Storm says no.
NW OBS says yes.
I didn't say yes? I am still looking for a way to change my throttle on the 'fly by wire' newer cars ('05/'06) the '07s have the function built into the ECM, like they ALL should be! :(
 
#219 ·
There is no way to raise the idle on any permentant basis (that I can find), except for reflash, and last I heard Bill at Ispeed hadn't looked into raising idle. The tps resets everytime you turn key off. If you adjust to alow more air at idle, the idle will surge between 600 and 2000 rpm.

If you have the nerve you can try drilling a tiny hole in tb, but it may also cause surging.

My engine never dies, but I dont have drive by wire.

I do have to reset ecu 2 or 3 times a month, after awhile it will really starts loose power, not sure what thats about.
 
#221 ·
Mine maybe worse than others since I have lwfw and lw underdrive crank pulley. Cel comes on after idling a few minutes, (misfire monitor). I reset the ecu and light may come back the 1st trip or may take a week.

Are you worried about the cel due to emissions testing or ???
 
#224 ·
Gumby647 said:
You could try increasing the valve lash to the loose side of factory spec. This will give less overlap and may help the idle some. Also if your engine management allows ignition timing adjustment at idle a little advance might help.
Gumby... Thanks for some very sound advice. I will actually try both down the road here ~ but I am getting this sorted out rather quickly to tell the truth... but I will still want some more RPM. So, I might be 1st in line at the 're-flash corral' at Subiefest in November!
 
#225 · (Edited)
Car Is Up And Running After The Delta Install!

OK. Update...

The car is no longer stalling. It runs strong and quick to the 5K I have been using for a shift point for the 1st 100 miles (6K after the first 100 miles, till a 1000 miles, when I dump the oil and go back to synthetic).

It appears that I may have shot my own self in the foot with the idle issue. I remembered I had put a PEP fix on the rear O2 sensor (MIL Eliminator) to stop a CEL that turned out to be the front O2 (with a warranty replacement of the front O2 sensor and a re-flash for that CEL ~ which fixed the issue).

Over my glass of wine last night after posting, I remembered the fix was still in. So, I crawled under the car and pulled it and spliced back in plain wire. Then reset the ECM. Went for a drive all excited that I had solved it... But, no. It kept stalling at stops.

I got home and pulled into the garage... the engine didn't stall. But it was 'on the cliff' looking to die every beat of the piston (sounded like an old car dieseling after it was shut off).

Instead of turning it off, I let it 'idle' (as it was). I watched a two hour movie and went back out to the garage ~ low and behold the car was idling at 750 rpms!

I went to bed. Got up this morning and started the car. It went right into 'fast idle' mode. Took a shower, got dressed and the car was back @ 750 rpms again when I was ready to roll for work.

The car did not stop ONCE today. In fact acted like it should. From a big sweep of the tach... it falls to 1000 rpms and sits for a second then drops to 750 rpms, just like it should!

Now, I would still prefer to be able to set the idle between 900-1000 (just so it's not so lumpy). But there is no doubt, this motor is no longer stock from the lumpy idle note...

So boys, we are ready to rock! Stand in line ~ The OEMs have been shipped to DJ!

I have the next two days off. So, by Friday I expect to be hammering it.
I will post again then. But, I am already impressed how hard it pulls and how smooth and flat the delivery is!

:bump:
 
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