advancing timing at high rpm?
07-01-03, 08:00 PM
#51
Rotary Freak
Join Date: Feb 2001
Location: MN
Posts: 2,524
Likes: 0
Received 0 Likes
on
0 Posts
back from the dead (again)
How about idle timing? I just got my 13B-RE running in my FB and while zeroing in the timing (running a E6K) I noticed it ran a lot smoother at 0 deg than at 20 deg BTDC. (900 rpm)
Also when you guys say you run X amount of split in the 0-2000rpm map do you have all ranges set to X amount or are you saying the most split is X? The map I have here has about 18 deg split at ~25in mercury and tapers down to 3 deg at 0 in mercury. Is that common?
Thanks, reading this thread now that I actually have a E6K makes a lot more sence to me
-Cam
How about idle timing? I just got my 13B-RE running in my FB and while zeroing in the timing (running a E6K) I noticed it ran a lot smoother at 0 deg than at 20 deg BTDC. (900 rpm)
Also when you guys say you run X amount of split in the 0-2000rpm map do you have all ranges set to X amount or are you saying the most split is X? The map I have here has about 18 deg split at ~25in mercury and tapers down to 3 deg at 0 in mercury. Is that common?
Thanks, reading this thread now that I actually have a E6K makes a lot more sence to me
-Cam
07-06-03, 07:11 PM
#53
Banned. I got OWNED!!!
Cam
Idle timming because of the very low speed of which things happen usually responds realy well to timing values in the range of -5 deg to 5 deg.
Some engines & IGN set ups have very narrow windows which hwen combined with a certain idle AF ratio will make the engine quite "happy" (stable combustion) with no or very little "vissible" cobustion residue visible from the tail pipe.
If you change the idle ign either side of it's ideal very much you will notice "smoke" at idle which is a sign that all is not burning eficiently (not oil smoke but fuel smoke).
It's a trial and error thing to suit your car, especially if its got a proper street port. I run about 11.2:1 a/f ratio and timing value around 2 deg ATDC with T&L together (no option for me to run split) and that works good on my engine for idle speed around 1100rpm
Idle timming because of the very low speed of which things happen usually responds realy well to timing values in the range of -5 deg to 5 deg.
Some engines & IGN set ups have very narrow windows which hwen combined with a certain idle AF ratio will make the engine quite "happy" (stable combustion) with no or very little "vissible" cobustion residue visible from the tail pipe.
If you change the idle ign either side of it's ideal very much you will notice "smoke" at idle which is a sign that all is not burning eficiently (not oil smoke but fuel smoke).
It's a trial and error thing to suit your car, especially if its got a proper street port. I run about 11.2:1 a/f ratio and timing value around 2 deg ATDC with T&L together (no option for me to run split) and that works good on my engine for idle speed around 1100rpm
07-06-03, 09:10 PM
#54
Rotary Freak
Join Date: Feb 2001
Location: MN
Posts: 2,524
Likes: 0
Received 0 Likes
on
0 Posts
Thank you very much! Thats what I wanted to hear! While reading this thread I was thinking to myself "WTF, people are saying run mid 20's up to 3k rpm in vacuum, but stock is set to 5 AFTER top dead center at idle" That probably explains why mine likes so much less than 20 btdc I'll have to kick the idle timing down and live with the louder exhaust note, at least it will idle better though
I think mine must have a vary narrow window to tune at idle. If I adjust fuel any more than 0.10ms in any dirrection it lets me know about it.
I have smoke at idle but thats for another reason... oil is deciding to creep past the turbine seal. I have a .060" restrictor in it now but I think I'm going to be forced to go to a .050" or maybe a .045". To make sure it wasn't the drain line I ran the engine with the drain run into a quart container. It still leaked by the turbine seal. It was passing nearly .3 gpm of oil at idle (45-50 psi before restrictor) so i think I'm safe to put a smaller restrictor in it.
Another question if you have time. With timing locked at idle I noticed that it "jumps" around maybe + - 2 deg, is this common with engines that use a CAS? Maybe some electrical interference in my system that is causing this? Or slop in the gears??
While reading this thread I was thinking to myself "WTF, people are saying run mid 20's up to 3k rpm in vacuum, but stock is set to 5 AFTER top dead center at idle" That probably explains why mine likes so much less than 20 btdc I'll have to kick the idle timing down and live with the louder exhaust note, at least it will idle better though I think mine must have a vary narrow window to tune at idle. If I adjust fuel any more than 0.10ms in any dirrection it lets me know about it.
I have smoke at idle but thats for another reason... oil is deciding to creep past the turbine seal. I have a .060" restrictor in it now but I think I'm going to be forced to go to a .050" or maybe a .045". To make sure it wasn't the drain line I ran the engine with the drain run into a quart container. It still leaked by the turbine seal. It was passing nearly .3 gpm of oil at idle (45-50 psi before restrictor) so i think I'm safe to put a smaller restrictor in it.
Another question if you have time. With timing locked at idle I noticed that it "jumps" around maybe + - 2 deg, is this common with engines that use a CAS? Maybe some electrical interference in my system that is causing this? Or slop in the gears??
07-07-03, 10:52 AM
#55
Senior Member
Join Date: Jun 2001
Location: CANADA
Posts: 440
Likes: 0
Received 0 Likes
on
0 Posts
Originally posted by RICE RACING
Cam
If you change the idle ign either side of it's ideal very much you will notice "smoke" at idle which is a sign that all is not burning eficiently (not oil smoke but fuel smoke).
Cam
If you change the idle ign either side of it's ideal very much you will notice "smoke" at idle which is a sign that all is not burning eficiently (not oil smoke but fuel smoke).
Thanks
07-07-03, 09:14 PM
#57
Resident Retard
Join Date: Apr 2001
Location: Cockaigne
Posts: 1,918
Likes: 0
Received 0 Likes
on
0 Posts
OK I have read and reread this thread. It's a great thread, but why in all of the maps on the forum, and elsewhere I might add, is NONE of the advice followed as far as I can tell.
07-07-03, 11:57 PM
#58
Resident Retard
Join Date: Apr 2001
Location: Cockaigne
Posts: 1,918
Likes: 0
Received 0 Likes
on
0 Posts
Too late to edit but I wanted to elaborate on my statement above. Re: the split map, no one that I can see runs 15 split up to 2K(P05) and then 8 thereafter. That would be easy to do. Is it recommended? Also mentioned was running in the 30's on the leading for low rpms, yet most if not all the maps start in the 20's (if that) at low rpm. I am looking for a way to increase response and power off boost.
09-17-03, 05:01 PM
#66
Boost Feels Good
Join Date: Jul 2002
Location: Georgia
Posts: 284
Likes: 0
Received 0 Likes
on
0 Posts
Originally posted by weaklink
Too late to edit but I wanted to elaborate on my statement above. Re: the split map, no one that I can see runs 15 split up to 2K(P05) and then 8 thereafter. That would be easy to do. Is it recommended? Also mentioned was running in the 30's on the leading for low rpms, yet most if not all the maps start in the 20's (if that) at low rpm. I am looking for a way to increase response and power off boost.
Too late to edit but I wanted to elaborate on my statement above. Re: the split map, no one that I can see runs 15 split up to 2K(P05) and then 8 thereafter. That would be easy to do. Is it recommended? Also mentioned was running in the 30's on the leading for low rpms, yet most if not all the maps start in the 20's (if that) at low rpm. I am looking for a way to increase response and power off boost.
Bringing this back up to see if we can get an answer as to if this is recommended.
03-17-04, 04:54 PM
#72
Photo Diety
Join Date: Mar 2001
Location: Florida
Posts: 2,311
Likes: 0
Received 0 Likes
on
0 Posts
One thing that isn't discussed is exhaust gas temps. RETed said, in a nutshell, that one should calibrate your EGT guage on the dyno with a wideband to know what is "normal" as different EGT guages will read differently on the same car and vice versa.
I am seeing EGT's at about 1000C at WOT on the dyno in 4th, 15 degrees leading adv., 7 degrees split with an a/f ratio of 11:1 or thereabouts. Wondering if I should be reducing my leading or increasing my split to lower EGT's (or will that just raise them?).
I am seeing EGT's at about 1000C at WOT on the dyno in 4th, 15 degrees leading adv., 7 degrees split with an a/f ratio of 11:1 or thereabouts. Wondering if I should be reducing my leading or increasing my split to lower EGT's (or will that just raise them?).
07-28-04, 08:07 AM
#75
Full Member
Join Date: May 2002
Location: United Kingdom
Posts: 142
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by rx7tt95
One thing that isn't discussed is exhaust gas temps. RETed said, in a nutshell, that one should calibrate your EGT guage on the dyno with a wideband to know what is "normal" as different EGT guages will read differently on the same car and vice versa.
I am seeing EGT's at about 1000C at WOT on the dyno in 4th, 15 degrees leading adv., 7 degrees split with an a/f ratio of 11:1 or thereabouts. Wondering if I should be reducing my leading or increasing my split to lower EGT's (or will that just raise them?).
I am seeing EGT's at about 1000C at WOT on the dyno in 4th, 15 degrees leading adv., 7 degrees split with an a/f ratio of 11:1 or thereabouts. Wondering if I should be reducing my leading or increasing my split to lower EGT's (or will that just raise them?).
Hi,
Can anyone shed some light over this? I reckon you are running too much advance and too little split.
John
88 GT-R