5500 rpm car misfire at 550hp
05-07-2012, 09:12 AM
#42
New Member
iTrader: (8)
Join Date: Jan 2007
Location: terre haute, IN; STL, MO
Posts: 6,457
Likes: 0
Received 7 Likes
on
6 Posts
They called me yesterday and told me it runs great now. Talking to jessi and Mac it sounded like it was really bad misfire. But when I got to talk to nick he said it wasn't the case. Just shows up as a slight misfire on computer. Not noticeable in car. He said its not knocking or showing up that way. They gapped the plugs down more and more until its barley there. Cannot go any further with te gap now he said. They ate hoping the coil packs will eliminate it completely. This is latest info I have.
and if it doesn't alter a/f or can't be felt then it's just a false reading so it actually doesn't exist. I still would like to know what they are using to detect this false misfire.
05-07-2012, 09:14 AM
#43
New Member
iTrader: (8)
Join Date: Jan 2007
Location: terre haute, IN; STL, MO
Posts: 6,457
Likes: 0
Received 7 Likes
on
6 Posts
We know that a stock ignition system in good working order will support near 1000hp cars without issues so to say you need to upgrade to support 550hp is just plain wrong. If the ignition can't support it then there is something wrong with this specific car.
i'm just agreeing with you jerry.
05-07-2012, 09:27 AM
#44
it's a band aid fix anyways. People love to throw parts on a problem to try to fix it without actually fixing the underlying problem. crazy how that works. Usually the crappy shops will do this.
We know that a stock ignition system in good working order will support near 1000hp cars without issues so to say you need to upgrade to support 550hp is just plain wrong. If the ignition can't support it then there is something wrong with this specific car.
i'm just agreeing with you jerry.
We know that a stock ignition system in good working order will support near 1000hp cars without issues so to say you need to upgrade to support 550hp is just plain wrong. If the ignition can't support it then there is something wrong with this specific car.
i'm just agreeing with you jerry.
05-07-2012, 09:43 AM
#45
crank position sensor determines misfire
so i'm confused, how is he seeing a misfire on the computer if he's not displaying knock? what other sensor can you monitor that will show a misfire?
and if it doesn't alter a/f or can't be felt then it's just a false reading so it actually doesn't exist. I still would like to know what they are using to detect this false misfire.
and if it doesn't alter a/f or can't be felt then it's just a false reading so it actually doesn't exist. I still would like to know what they are using to detect this false misfire.
05-07-2012, 09:44 AM
#46
New Member
iTrader: (8)
Join Date: Jan 2007
Location: terre haute, IN; STL, MO
Posts: 6,457
Likes: 0
Received 7 Likes
on
6 Posts
With a misfire there are 3 things leading to the problem: spark, fuel, air
i doubt it's air flow.
spark either plug or coil
fuel would be from injector
Ask them what they are "seeing" a misfire with. Computer is not a good enough answer. I want to know what sensor they are monitoring and how they are thinking this is a misfire if there are no symptoms at all.
05-07-2012, 04:43 PM
#49
I have no idea about tuning cars. I just put the damn thing together and gave it to the shop to tune. So I can't really answer for anything there doing at the momment. Il take the information you guys have gave me about it and ask them on Tuesday and let u know.
05-08-2012, 03:59 PM
#50
I was able to talk to them today for a min. They said they monitor knock and nothing showed up. They said its not a timing issue and that only at 5500 rpm does it break up. The rest of the rpm range is fine. They said its most likely an electrICal Issue. That is all I know. The new coilS are going on today. If its not that they are checking wiring next.
05-09-2012, 11:16 AM
#51
New Member
iTrader: (8)
Join Date: Jan 2007
Location: terre haute, IN; STL, MO
Posts: 6,457
Likes: 0
Received 7 Likes
on
6 Posts
I was able to talk to them today for a min. They said they monitor knock and nothing showed up. They said its not a timing issue and that only at 5500 rpm does it break up. The rest of the rpm range is fine. They said its most likely an electrICal Issue. That is all I know. The new coilS are going on today. If its not that they are checking wiring next.
05-10-2012, 05:28 AM
#53
This is only true for an EMS that has Dwell control, which Osiris unfortunately does not. I ran out of spark at around 580rwhp on pump, and have come across a handful of other stock ECU high HP cars with such blowout. An HKS Ignition amp solved my issue, I then pushed that setup to 633rwhp/667ft-lb until I recently switched to Haltech.
05-10-2012, 06:56 AM
#55
This is only true for an EMS that has Dwell control, which Osiris unfortunately does not. I ran out of spark at around 580rwhp on pump, and have come across a handful of other stock ECU high HP cars with such blowout. An HKS Ignition amp solved my issue, I then pushed that setup to 633rwhp/667ft-lb until I recently switched to Haltech.
05-10-2012, 07:14 AM
#56
Not sure, I believe Hal did some testing with Dwell, He may know.
Mine occurred between 6-6.1k every pull, the only way to make it rev higher was to pull the boost back. I ran the HKS amp for probably 6 months with no coil pack problems. We have several customers who have been running it for years without issue.
If you can't find one, I have a brand new one I might part with. I happened to come across a used one while I was waiting for the new one to arrive. I've held on to it in case I decided to run it along with the Haltech.
Edit: I remember Jesse having a similar problem before he ditched the stock ECU also.
https://my350z.com/forum/8817812-post64.html
If you can't find one, I have a brand new one I might part with. I happened to come across a used one while I was waiting for the new one to arrive. I've held on to it in case I decided to run it along with the Haltech.
Edit: I remember Jesse having a similar problem before he ditched the stock ECU also.
https://my350z.com/forum/8817812-post64.html
Last edited by Rob@Z1; 05-10-2012 at 07:33 AM.
05-10-2012, 07:30 AM
#57
Not sure, I believe Hal did some testing with Dwell, He may know.
Mine occurred between 6-6.1k every pull, the only way to make it rev higher was to pull the boost back. I ran the HKS amp for probably 6 months with no coil pack problems. We have several customers who have been running it for years without issue.
If you can't find one, I have a brand new one I might part with. I happened to come across a used one while I was waiting for the new one to arrive. I've held on to it in case I decided to run it along with the Haltech.
Mine occurred between 6-6.1k every pull, the only way to make it rev higher was to pull the boost back. I ran the HKS amp for probably 6 months with no coil pack problems. We have several customers who have been running it for years without issue.
If you can't find one, I have a brand new one I might part with. I happened to come across a used one while I was waiting for the new one to arrive. I've held on to it in case I decided to run it along with the Haltech.
05-10-2012, 07:37 AM
#58
As far as my amp, i'll have to try to dig up what I paid for it. I'll PM you once I find out.
Last edited by Rob@Z1; 05-10-2012 at 09:04 AM.
05-15-2012, 02:21 PM
#59
Good news
Ok so it ended up being the coil packs that were bad. They swapped em out and there is no more misfire. Final dyno numbers were. 565 whp and 580tq at 17 psi. I told them to hold off on taking it any higher until I get a twin pump and more injector even though there was room to go. Il post dyno sheet later when they email it to me.