When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
On my stock springs i felt a slight nose dive as I got closer to 6100-6300 on the stock tach, with the new springs it's solid the whole way. If you can get it to shift at 6300 by the stock tach and have the valvetrain you selected supporting it, you'll go way faster and should do mid 12s. But you also need to fix that header touching the motor mount or k member.
But you also need to fix that header touching the motor mount or k member.
I'll probably try to look at that soon. I logged a run the other day and I'm getting crazy knock counts in second between 4000rpm and 5500rpm. Really thinking it's the exhaust. I may pull a bunch of timing in that area and run it to see if it still does it. Not sure what I'm going to do with the header touching the motor mount. I don't want to dent the primary, may be able to just tweak it. It's actually touching the metal part that bolts to the block so a new motor mount won't help that. may just get in there with a prybar, or do some grinding on the mount.
Next TnT is 4 weeks away. Air should be nice and cool then. I'm really expecting to dip into the 12s, but I'll be posting a timeslip regardless.
went tonight
since last time I installed springs, rockers, changed shift points to 6000rpm, took the ebay cai off and put the stock airbox back on.
made one run and trans fluid spayed out the dipstick tube and smoked out the track....
obviously I couldn't make another run. I got a warning
It ran much slower than last time
1.94 60ft
8.69@81.18 1/8th
13.58@100.96 1/4 mile
DA 336
I do know that the factory airbox sucks. I put it back on in place of the cheap ebay cai,
baro was 103.0 and MAP at 5700 was 93.4, So i'm guessing that I lost a little there. I just don't know what's up with my time. especially the trap.
Thinking it's time for a new tranny and a stall...
The shifts were great though. Shifted at 6k firm So IDK
The rpm in third shows really uneven in the log. it's like it's slipping and I can't feel it?
black line is speed, red is rpm. What's up with that?
I know it's done that everytime I've run it. I attributed it to the lockup converter locking wot in third. (factory setting) I did disable that this time.
Just don't know what to think..
Last edited by fbody_brian; 11-04-2015 at 09:19 PM.
I would put back on the eBay CAI, if it is on tight it works, I know it's ugly and stupid looking but it flows a ton more than stock. That's 1 variable I would not have changed, it's like you're making your motor breath through a straw and run a 400m. You added air with the rockers but choked it with the intake IMO.
Did you fix the header touching the k member? Could be false knock.
Are the rockers set right? Not over tight causing bad valve seal? Did it idle/run smooth as before you put them on? Did you accidentally bump a vacuum line and maybe have a leak?
Your 1/8th mph tells me it's not the trans, as you're showing the 3rd gear issue but 3rd should be after the 1/8th correct?
I would put back on the eBay CAI, if it is on tight it works, I know it's ugly and stupid looking but it flows a ton more than stock. That's 1 variable I would not have changed, it's like you're making your motor breath through a straw and run a 400m. You added air with the rockers but choked it with the intake IMO.
I agree, I think that the stock airbox lost me some hp. going to try to fab up a better one.
Originally Posted by bufmatmuslepants
Did you fix the header touching the k member? Could be false knock.
It's not touching the k member, it's actually touching the motor mount bracket that attaches to the block. I was able to tweak it some. Think my false knock is gone.
Originally Posted by bufmatmuslepants
Are the rockers set right? Not over tight causing bad valve seal? Did it idle/run smooth as before you put them on? Did you accidentally bump a vacuum line and maybe have a leak?
I have the preload set to 1/2 turn past 0 lash. It idles as smooth as can be.
I did find out that my fpr was bad and replaced it the day before i went to the track. I think that it was running lean. I know that narrow band o2s are not super accurate, but previously my wot runs the o2 mv sat at around 920-980, on that run they were at about 820-850. Also previous runs in the very upper rpms injector duty cycle showed just over 80%, this run they only went to just over 70%.
on top of that I normally fuel up at the chevron before I go to the track. Just enough to make my passes. This time I had a full tank from the kangaroo station.....
need to do a fuel pressure test to confirm that pressure is good, need new spark plugs. need a cai, need to get a wideband!!
Originally Posted by bufmatmuslepants
Your 1/8th mph tells me it's not the trans, as you're showing the 3rd gear issue but 3rd should be after the 1/8th correct?
Yes! I actually lost on the 60' and the 1/8th too.
I think that it was a combination of things. going to try to get it straightened out and go back in a month.
I just realized. My 13.3 run, the car was in closed loop. I had a problem with an o2 sensor and raised the temp to enter closed loop so the car would idle and not stumble off idle. I ran the slower time in open loop. Pe mode is never used in open loop, is it?
So my afr could have been way different between these runs.
So what was your previous best? a 13.3 @ 104 with 1.9 60?
Yes, I'm pretty stoked.
First time to the track with it I ran a best of 13.76, so I've dropped almost a full second.
previous best was 13.36@104 with the 1.92 60.
so i dropped 4 tenths in the 1/4 since the rocker install.
I attribute some to the cooler air. But I think that the 1.7s, 160 stat, pulled a little timing in the 4-4500 area and raised shift points all helped.
I did a bit of tuning trying to get the afr straight now that I have a wideband. it's still lean up above 5900.
I honestly think the fix was tuning. I was running closed loop before and I switched to full time open loop before that crappy run. Just tired of trying to get it to run good with the o2s and the long tubes.
I believe that i was getting serious knock and timing retard last time out because it was way lean at wot. last night my afr was right at 13.2 all the way up to 5900 where it went lean. going to try to get it closer to 12.8 leaning out to 13.2 in the upper rpms.
Very happy to have hit a 12 with minor basic bolt ons. I'm thinking that with a good stall I should be deep in the 12s.
any guesstimates on how much power it's putting down now?
I tried some of the online calculators, just doesn't seem right. I was thinking it's making possibly 330 fwhp. No way it's making that to the wheels.
what's it take to run 105.85 mph trap in a full weight formula?
I mean, it doesn't really matter. car runs strong for what it's got, I'm just curious.
I honestly think the fix was tuning. I was running closed loop before and I switched to full time open loop before that crappy run. Just tired of trying to get it to run good with the o2s and the long tubes.
It's not the tuning. You have some kind of issue that you are covering up using open loop. You should have no problem running in closed loop with long tubes....I'm running long tubes with a CC503 cam/1.6 RR, cats, O2 extensions, and full emissions. I have no issues in closed loop.
I understand your frustration of just wanting it to run right, but sometimes you have to really hang in there to solve tough problems. I pulled the engine out of my Z28 two or three times trying to track down an issue with oil pressure dipping 20psi between 3k and 5k on hard acceleration. After a year or so, I finally fixed it with a combo change of an oil pickup and pan.
The car needs to be fully data logged in closed loop then that data studied to try and nail down what is going on with it.
Get on ScannerDanner's youtube channel and start watching some of his vids on troubleshooting rich/lean conditions along with O2 operation and troubleshooting.
In my first post in your other thread, I think I screwed up with my first post....I thought the car was lean as you mentioned pegged on the blm and I instantly thought maxed...as in positive trims...but your blms were 108 which actually is negative or pulling fuel. That is a lean command to a rich O2 signal. So it thinks too little O2 in the exhaust.
I really need a data log of everything to see what it's doing in closed loop.
It's not the tuning. You have some kind of issue that you are covering up using open loop. You should have no problem running in closed loop with long tubes....I'm running long tubes with a CC503 cam/1.6 RR, cats, O2 extensions, and full emissions. I have no issues in closed loop.
I understand your frustration of just wanting it to run right, but sometimes you have to really hang in there to solve tough problems. I pulled the engine out of my Z28 two or three times trying to track down an issue with oil pressure dipping 20psi between 3k and 5k on hard acceleration. After a year or so, I finally fixed it with a combo change of an oil pickup and pan.
The car needs to be fully data logged in closed loop then that data studied to try and nail down what is going on with it.
Get on ScannerDanner's youtube channel and start watching some of his vids on troubleshooting rich/lean conditions along with O2 operation and troubleshooting.
In my first post in your other thread, I think I screwed up with my first post....I thought the car was lean as you mentioned pegged on the blm and I instantly thought maxed...as in positive trims...but your blms were 108 which actually is negative or pulling fuel. That is a lean command to a rich O2 signal. So it thinks too little O2 in the exhaust.
I really need a data log of everything to see what it's doing in closed loop.
This.
OP, did you adjust your O2 tables? 02 INT Delay, etc? Read this by Steveo (a member here). Good info.
OP, did you adjust your O2 tables? 02 INT Delay, etc? Read this by Steveo (a member here). Good info.
Yes, this was all done. I've not been able to get it to idle good in closed loop no matter what these have been set to, and it has a terrible stall on throttle tip in.
I'm starting to think that I have a fuel injector issue. When I first start the car and it's cold it sits at around 14:1 afr, by the end of a 30 minute drive it has dropped to 11:1 and the fumes are terrible. This is in open loop, so the o2s are out of the equation.
I think that they may be leaking when they get hot. Does that sound possible? What else would cause this?
I think it WAS tuning. The question was in reference to the issue I was having in third gear, NOT the issue I was having with my o2s and closed loop. Obviously I fixed something, right, I went from having issues in third and running a 13.58, to not having issues and running a 12.95.
Yes, this was all done. I've not been able to get it to idle good in closed loop no matter what these have been set to, and it has a terrible stall on throttle tip in.
I'm starting to think that I have a fuel injector issue. When I first start the car and it's cold it sits at around 14:1 afr, by the end of a 30 minute drive it has dropped to 11:1 and the fumes are terrible. This is in open loop, so the o2s are out of the equation.
I think that they may be leaking when they get hot. Does that sound possible? What else would cause this?
Could be a weak ICM messing up spark as it gets hot, did you do the ICM spacer mod? What spark plugs are you running?
Could also be a MAP sensor going out (heat induced failure type deal). I've had this happen to me. In SD mode the car won't run, in MAF it'll run like crap. But that should give you a CEL.
If you've already confirmed that all the mechanical side of things are good, I'd be looking at the sensors the engine uses to fuel before the O2s and how good the spark is (timing and strength).
Could be a weak ICM messing up spark as it gets hot, did you do the ICM spacer mod? What spark plugs are you running?
Could also be a MAP sensor going out (heat induced failure type deal). I've had this happen to me. In SD mode the car won't run, in MAF it'll run like crap. But that should give you a CEL.
If you've already confirmed that all the mechanical side of things are good, I'd be looking at the sensors the engine uses to fuel before the O2s and how good the spark is (timing and strength).
Don't think it's a MAP issue, though I could be wrong about that. My MAF has given me issues before, but I fixed the MAF harness and cleared up that issue. I ran it in SD and it did the same thing, getting really rich after a 30 minute drive. There's definitely something wrong here.
I have a spare ICM so I could swap that with no problem, and yes it is spaced off of the head.
It's only at idle and off idle that I have problems. car runs great, but my idle AFR is just inconsistent.
If it were the ICM wouldn't it cause issues outside of idle and wouldn't I have problems under load?
The reason I ask is that it is running pretty damn good outside of idle issues, which seems to be backed up by the timeslip.
also spark plugs are tr55s
Last edited by fbody_brian; 12-08-2015 at 02:43 PM.
10-09-2015, 05:39 AM
