Getting my new 406 SBC installed, running, and driving

[townsend]

slow down the front extension and go up a little in tire pressure. looks like similiar issue to mine, front extends tops out quick and the tire wads then unloads

[IROCZman15]

Any and all advice is appreciated, thanks guys!


Brian:
yea, I had a bunch of email exchanges with sending files back and forth to Holley for their tech guys to look at, this was sometime last year, but they were stumped. We tried lots of things, but the one thing I was hesitant to try was a full software update on the ECU and the computer itself. I've been always hesitant to do this, because I continually come across threads on the Holley sniper forum where people will do a software update and then the ECU gets locked up, or something goes awry. However, now that I am truly out of options, I might end up doing it.
Matt: yea, maybe I could find a way to check into that facebook page. but I don't have facebook account so that complicates it. Possibly could try using my wife's facebook, but she may not be too thrilled about it! I've been surprised that the EFI guru's on the holley forum still have never come across this either. The issues began in September of 2021 and are totally intermittent and random.
the thread: https://forums.holley.com/forum/holl...agstrip-passes

Townsend:
Its good to see the videos Joe took to see that the tire is indeed too low. I always keep log books from each track day, and I refer back to them for stuff like tire pressure and air-bag settings. Going back to my book for tire pressure I see that I had some of my best 60foot launches with the tire right around 17, often lower:
1.54 sixty with a 17.0 psi rear tire (all motor) April 15, 2022 Pass 3
1.44 sixty with a 17.0 psi tire (nitrous launch) May 1, 2022 Pass 4
1.49 sixty with a 17.6 psi rear tire (all motor) September 25, 2022 Pass 2
1.46 sixty with a 17.4 psi rear tire (nitrous launch) September 25, 2022 Pass 3
1.42 sixty with a 17.4 psi rear tire (nitrous launch) October 9, 2022 Pass 1
1.43 sixty with a 16.0 psi rear tire (nitrous launch) October 9, 2022 Pass 3
1.52 sixty with a 17.2 psi rear tire (all motor) October 16, 2022 Pass 1
1.51 sixty with a 16.4 psi rear tire (all motor) October 16, 2022 Pass 3
1.54 sixty with a 16.6 psi rear tire (all motor) October 16, 2022 Pass 4
1.52 sixty with a 16.6 psi tire (all motor) May 5, 2023 Pass 3
1.49 sixty with a 16.8 or 17? tire (all motor) may 5, 2023 Pass 4
1.48 sixty with a 16.8 psi rear tire (nitrous) May 5, 2023 Pass 6



But I agree, I am going to keep more air in the rear tire. I think I feel exactly what you are describing, how the tire unloads a little bit as it launches. You can hear it in some of the videos. Thanks for pointing that out !
Back a while ago I did have the rear tires higher in psi, (also I thinik I ran higher psi on the same version of these tires but a 26" tall tire on a 16" wheel). The converter was different then, and I also didn't have the Lakewood front/rear drag shocks. These lakewoods are a 90/10 strut up front (not adjustable) and a 50/50 rear shock (not adjustable). My Koni struts and shocks are adjustable, but more for handling and autocross. So My adjustments can come from tire pressure and air bag pressure. LCA angle and torque arm are dialed in and on the proper location holes.


Hoping to resolve a few issues in the coming week and possibly get out to the track next friday night (might be away the remainder of the memorial day weekend).

[townsend]

Originally Posted by IROCZman15

Any and all advice is appreciated, thanks guys!


Brian:
yea, I had a bunch of email exchanges with sending files back and forth to Holley for their tech guys to look at, this was sometime last year, but they were stumped. We tried lots of things, but the one thing I was hesitant to try was a full software update on the ECU and the computer itself. I've been always hesitant to do this, because I continually come across threads on the Holley sniper forum where people will do a software update and then the ECU gets locked up, or something goes awry. However, now that I am truly out of options, I might end up doing it.
Matt: yea, maybe I could find a way to check into that facebook page. but I don't have facebook account so that complicates it. Possibly could try using my wife's facebook, but she may not be too thrilled about it! I've been surprised that the EFI guru's on the holley forum still have never come across this either. The issues began in September of 2021 and are totally intermittent and random.
the thread: https://forums.holley.com/forum/holl...agstrip-passes

Townsend:
Its good to see the videos Joe took to see that the tire is indeed too low. I always keep log books from each track day, and I refer back to them for stuff like tire pressure and air-bag settings. Going back to my book for tire pressure I see that I had some of my best 60foot launches with the tire right around 17, often lower:
1.54 sixty with a 17.0 psi rear tire (all motor) April 15, 2022 Pass 3
1.44 sixty with a 17.0 psi tire (nitrous launch) May 1, 2022 Pass 4
1.49 sixty with a 17.6 psi rear tire (all motor) September 25, 2022 Pass 2
1.46 sixty with a 17.4 psi rear tire (nitrous launch) September 25, 2022 Pass 3
1.42 sixty with a 17.4 psi rear tire (nitrous launch) October 9, 2022 Pass 1
1.43 sixty with a 16.0 psi rear tire (nitrous launch) October 9, 2022 Pass 3
1.52 sixty with a 17.2 psi rear tire (all motor) October 16, 2022 Pass 1
1.51 sixty with a 16.4 psi rear tire (all motor) October 16, 2022 Pass 3
1.54 sixty with a 16.6 psi rear tire (all motor) October 16, 2022 Pass 4
1.52 sixty with a 16.6 psi tire (all motor) May 5, 2023 Pass 3
1.49 sixty with a 16.8 or 17? tire (all motor) may 5, 2023 Pass 4
1.48 sixty with a 16.8 psi rear tire (nitrous) May 5, 2023 Pass 6



But I agree, I am going to keep more air in the rear tire. I think I feel exactly what you are describing, how the tire unloads a little bit as it launches. You can hear it in some of the videos. Thanks for pointing that out !
Back a while ago I did have the rear tires higher in psi, (also I thinik I ran higher psi on the same version of these tires but a 26" tall tire on a 16" wheel). The converter was different then, and I also didn't have the Lakewood front/rear drag shocks. These lakewoods are a 90/10 strut up front (not adjustable) and a 50/50 rear shock (not adjustable). My Koni struts and shocks are adjustable, but more for handling and autocross. So My adjustments can come from tire pressure and air bag pressure. LCA angle and torque arm are dialed in and on the proper location holes.


Hoping to resolve a few issues in the coming week and possibly get out to the track next friday night (might be away the remainder of the memorial day weekend).

i would honestly put your koni's back on, they will be stiff enough to slow down alot of what is going on full soft, i went 1.47 with 0 suspension tuning on koni yellows/umi lowering springs.

youre gonna be fighting the shocks now. not ideal. the lakewood 90/10-50/50 combo works great on leaf spring stuff etc, but not that efficient trying to go fast on a modern radial

they changed the no time grudge race to tomorrow and i talked to melissa, she said i could jump in as test and tune but ill probably only get 3 runs. deciding if i should try it anyway because atleast since they have a race the prep should be better than a friday night.

i may try to go friday too

[IROCZman15]

Woah, that would be interesting, but I'd be willing to do it after I get another go at the track with these Lakewoods. The Konis did have that adjustability but I had heard some good success stories with the 50/50s on Thirdgen.org. I will give it a shot one day with the Konis again, probably in August after I am done playing around on the July autocross events, that way the konis will already be on the car.

I am thinking maybe I can get there next Friday night. Possibly.

[townsend]

Originally Posted by IROCZman15

Woah, that would be interesting, but I'd be willing to do it after I get another go at the track with these Lakewoods. The Konis did have that adjustability but I had heard some good success stories with the 50/50s on Thirdgen.org. I will give it a shot one day with the Konis again, probably in August after I am done playing around on the July autocross events, that way the konis will already be on the car.

I am thinking maybe I can get there next Friday night. Possibly.

I may go friday just to watch, got my 9 second pass today. 9.90 with a 1.26 60ft. finally got it to leave correctly. stiffening my shocks and changing the lca angle to 2 degrees helped

[IROCZman15]

You got a 9.90 ! Thats killer. I am definitely going to have to pick your brain on some more of this stuff. What size nitrous hit was it 200? I've always seen the 200 shot as the limit for my car/systems/solenoids, but I would be lucky to go 10.40 with it. 9.90 at 131 is awesome, but that 1.26 sixty foot is quick! nice job man. I'm still tentative about this Friday, much to do beforehand plus possibly family duties, but I am going to push as hard as I can to get packed and try to make it.

[townsend]

Originally Posted by IROCZman15

You got a 9.90 ! Thats killer. I am definitely going to have to pick your brain on some more of this stuff. What size nitrous hit was it 200? I've always seen the 200 shot as the limit for my car/systems/solenoids, but I would be lucky to go 10.40 with it. 9.90 at 131 is awesome, but that 1.26 sixty foot is quick! nice job man. I'm still tentative about this Friday, much to do beforehand plus possibly family duties, but I am going to push as hard as I can to get packed and try to make it.

i think you will be surprised that you will probably go faster on a 200 than you think. for reference my cars fastest motor hit was 11.67 at 114. with the suspension adjustments off the trailer on a 150shot went 10.34 with a 1.31 60ft. 200shot and got a 9.93 and a 9.90

my window switch was acting up, so i removed it. nitrous is just on a wot switch now. i only have a single nozzle before the throttle body (stock lt1 throttle body). nothing special. my solenoids are 15 year old nitrous outlet max 250hp solenoids. only thing i got going for me is i have a 6an nitrous feed line from bottle to solenoid.

im gonna try to go friday too, thinking of driving the car there and home instead of trailering it, prove its a street car. ive driven it much further without issue so far. probably just jet it back to 150 since its a friday night.

[IROCZman15]

Yea, I would like to be hopeful about that too. Oddly, I have never seemed to get the timeslips that I feel a 100 shot or a 150 shot should achieve. I don't know if its my self-created combination of jets, or the use of a plate instead of a port system, but I had imagined a few tenths faster from each corresponding nitrous shot up-jet. I do hope to figure it out, could really use a dyno session to accomplish this I think. Too much variables with street/track. Your setup is fairly straightforward too though, single nozzle before the throttle blades, and I like simple.. but yours seems to really work well with waking that car up from a mid 11.67 to a 9.90 on a 200 shot. Numbers like that give me hope of maybe grabbing a 10.30 one day.

I am still trying to sort out what our weekend gameplan is for the family. I am full-tilt trying to work in a TnT session, but only if we don't go out to PA for the weekend to visit my wifes family. I am also considering the option of going on Sunday for TnT but not counting out tomorrow night Tnt. I hope to know by mid-day tomorrow and I will try to update ya on here.

[townsend]

i think we can get it figured out. lookin like im going to go sunday.

What plate and jetting are you going off of? most efi plates a .062 jet is 150hp give or take. i followed nitrous outlets jetting chart for a single nozzle/plate and got it close, but ended up having to go up 2 fuel jet sizes from their recommended for both the 150 and 200 shot.

[IROCZman15]

I should be going today. Wasn’t able to get to sort out a few things are other teh firmware/software but did take care of some other stuff.

I’ve always been curious about my nitrous jetting. I made my own jet chart as I couldn’t find a jet chart for the fuel pressure I have at the system which is 65 psi. I also used that Robbie the robot calculator to guide me but that’s just internet math, real life use seems to be different. I really
Need to get the nitrous jet/tune setup on a dyno and I know that, so that will be a goal for 2023. According to your jet numbers and my “tame” jet chart, I think my
Numbers for a 150 shot put it closer to a 120
Shot and my numbers for a 175 shot are more like a 150
Shot . I have the .062 nitrous jet and .032 fuel jet in there now. Nitrous bottle pressure will be at 950 today and fuel
Pressure is 65 psi at the gauge where the fuel
System T’s off . Without useable datalogs, all
I have is visually seeing the afr numbers on the gauges as I go down the track. Might setup the GoPro to record the gauges? Gotta check spark plugs of course too. Will use a splash of the race gas concentrate in the can.



http://robietherobot.com/nitrousjetcalculator.htm


https://flic.kr/p/2oDprs4

[IROCZman15]

Bad day today on many levels. Lots of stuff I can’t figure out


Problems with:
Laptop
Firmware
Software
Data logging
No rpm signal/trace at all on all data-logs
Rpm needle bouncing all over the place at idle
Backfiring and popping under load
Unknown issues still with nitrous


Not sure I’ll be able to find time to dig into it. Probably not able to to drive the car to Carlisle or to UMI autocross with it acting this way

[townsend]

Originally Posted by IROCZman15

Bad day today on many levels. Lots of stuff I can’t figure out


Problems with:
Laptop
Firmware
Software
Data logging
No rpm signal/trace at all on all data-logs
Rpm needle bouncing all over the place at idle
Backfiring and popping under load
Unknown issues still with nitrous


Not sure I’ll be able to find time to dig into it. Probably not able to to drive the car to Carlisle or to UMI autocross with it acting this way

sounds like an issue with the holley getting signal. dont feel bad, i didnt make it either, have maintenance stuff to do to the car as i have just been beating on it lately. also got the other car running and having 24x conversion issues

[V]

I want to get to a Friday night TnT soon but I need to get a helmet and jacket first.

[townsend]

that damn hyperspark wiring

[IROCZman15]

This is a long overdue update post, but I did get to teh track back on may 28. I did some stuff prior and thought I had all the gremlins worked out. Unknown to me, is that the misfire likes to come around after the car has been driven and warmed up...so that caused havoc at the track. I no longer have any of the dashcam videos, but three of the 5 runs i got were garbage due to the misfire coming about. And I spent a good amount of time in teh pits checking over wiring, plugs, swapping to known good tunes etc, but in the end, I only had two full passes (#1 and #3). Pass 3 got me a great mph in the 8th mile at 95.49 mph and the 1/4 mile was 118.69 mph which is a p.b., and I didnt feel the misfire that time, but in actuality, it was partially there.

( this video below is the only track video and it was pass 5)

https://www.youtube.com/watch?v=CJh_3mlNC_M


timeslips:







but:
here is the wild stuff the tachometer on BOTH the oem dashboard gauge and the digital holley gauge was going. The engine was not changing rpm that quick, but the computer was seeing the values and compensating afterwards with big swings in the timing, IAC, and whatnot. However, the other gauges and values on both dashboards were clear and steady (free from the spike) so I kept ruling out RMI and electrical interference.


videos:

https://www.youtube.com/shorts/CnW9JtzeRs0


https://www.youtube.com/shorts/czgIdSJL2uU






Drove the car home gently and took a few days to dig into it. Started at the battery in the back and dug deep into the wiring all the way up through the body, under the console, into the engine bay, etc. Checked timing with a timing light, static timing tests, installed ferrite beads on some wires, moved plug wires, even unclipped connectors and checked a bunch of the tiny pins. Ran a vacuum test on the engine and almost pulled some valve covers off too, but I had been chatting with Scott over at EFI systemsPro and he mentioned that it seems the ecu is getting a bad signal from the distributor, and that lead me to start checking the wiring there. Thats when i saw it: at some point in time (probably when I had the intake manifold off last year) I must have removed some of the plastic loom that usually covers all of my wiring, from teh 3-wires that go into the underside of the hyperspark distributor. The unprotected wires were then left to sit alongside the sharp edge of the distributor hold-down clamp, and that caused them to get sliced open over time. Whew! I got the wires sealed, shrink wrapped, secured and with plastic loom back on it. Car fired right up and ran smoooooooooooth. Test drive went well also. whew.






Datalog screenshots from Pass 2:
(see the bright red, thats rpm, and it looks noisy, but spikes and dips) not in a cycle or rhythym either, just intermittent, this is what baffled my brain) this log is idling in the stagin area, burnout, and then the 1/4 mile pass which let off after a bit)




Closeup of the spikes during idle:



closeup of the rpm spikes during pass 2:



Pass 3 was much cleaner, but I was ready to get off the throttle if I detected big misfires. According to the log, there were a very slight few which i only felt at the top end:





The sliced wires (not sure how I overlooked it, but i did)





.






Also:
I did a complete holley efi software download, I loaded up the newest firmware onto the handheld, and loaded the newest holley sniper ecu firmware, and bought a new 8gb SD card for the sniper too. This was a crazy thing for me to do because I am a very low-tech person.
I did this because of the wild looking datalogs I was getting where there was tons of missing data. And, success. the firmware, sd card, software now has me up-to date and free from missing data in the logs.



I wanted to do new pads and rotors for the front this winter, but just didn't get to it. My rotors had turned ugly over years of autocross and dragracing with them, and I only had a little bit of pad life left anyway. A clean set of front rotors will be good for Carlisle, and great for UMI in July. Bolted on the powerstop Z23 font kit for 1LE brakes/C4 HD, and painted the calipers afterwards. Also removed the front lakewood 90/10 drag struts and rear lakewood 50/50 drag shocks, and put on the adjustable koni yellows. Bolted the front sway bar back on with all new bushings on the endlinks. Installed new "roof-rail" (upper window) weatherstripping just this weekend also, and painted the rear decklid's metal trim black as it was nasty.



This was the flat-black metal primer. I went with a satin finish and it turned out good, but no photos of it at the moment.







Still hopefully going to find time to get a full detail job on the paint and under the hood in hops of getting to Carlisle next weekend. car is running gooooood though!

[thehazguy]

Good news Dave. Gremlins suck.

Be safe. Hope the little man is doing better.

Took the 57 out for the first time this year. Went to the Cars and Coffee Saturday at Island. Good turn out. Need to tweet out the carb after being refreshed. Then maybe a Friday night session.

https://youtu.be/EFsyEWGRV30

[townsend]

awesome to see you got this sorted out

[IROCZman15]

Thanks guys. I was baffled for a bit by it, no doubt.
Jerry, thats awesome you got the car out and about because its been a while since the Fall season. I still have a photo to give to you next time of you in the winners circle with a trophy, a real printed out photo!

[Blackbirdws6]

Glad you got it sorted out and its running good!

[IROCZman15]

Completed the last minute thrash to get the car cleaned up, detailed, and ready for Carlisle on Monday of last week. Left at noon on Thursday and drove through some good patches of rain, to arrive at Carlisle at 3pm. Dried the car off after registering and getting parked in the building. Bunch of my buddies were already there and more came throughout the weekend. It was awesome to see a good amount of cars and people I knew, but also chilling with new people was awesome. There was 9 of us in the building R display which was awesome, but overall I think we had about 70-80 thirdgens, and then probably 45-50 fourthgens. I took some photos, but not as many as I used to. Drove home after everything ended on Saturday, including rainstorms, but overall, it was awesome. Put about 360 miles on the car, which ran really really really well. I just have to source out the oil leak at the back of the engine (again) because occasionally I would get a whiff of burning oil from there. All the EFI stuff was dialed in and it was nice to drive the car with the konis, street wheels, front sway bar, and sound system back installed. My buddy John won the exhaust competition with his firebird. The did both a 3rd gen parade and a 4th gen parade driving the fairgrounds too.

[IROCZman15]

More photos:

[Blackbirdws6]

Another friend of mine (Michael Fay) had his 4th gen formula LSx inside the building on display (graphite wrapped car). I always seem to forget about this event but will try to get there one of these years. Glad you had a good time and hope the weather held off somewhat reasonably.

How did you go about getting to display in the building?

[townsend]

Originally Posted by Blackbirdws6

Another friend of mine (Michael Fay) had his 4th gen formula LSx inside the building on display (graphite wrapped car). I always seem to forget about this event but will try to get there one of these years. Glad you had a good time and hope the weather held off somewhat reasonably.

How did you go about getting to display in the building?

heard they dont take lt1's with leaky oil pans

[Blackbirdws6]

Originally Posted by townsend

heard they dont take lt1's with leaky oil pans

So no LT1's then. Got it.

[townsend]

Originally Posted by Blackbirdws6

So no LT1's then. Got it.

i see what you did there