Author Topic: Tune Changed Overnight  (Read 7035 times)

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Thumperbird

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Tune Changed Overnight
« on: June 14, 2019, 08:23:36 PM »
445 Stroker dual quad.  So a couple days ago I spent an hour dialing eveything in from float level to timing, idle speed, idle mix, you name it, was running very well and pulling hard, could not keep traction.  Today I go for a ride and it seems rich, idles a couple hundred higher, bogs, and runs on when shut off.  What happened?  Temperature is maybe 10 degrees different (cooler) at most but engine seems to be running a little warmer than before as well, used to be failry solid 180 now 190.

427LX

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Re: Tune Changed Overnight
« Reply #1 on: June 14, 2019, 08:41:04 PM »
What was the weather like when you tuned it and when the tune seemed to change?

I have seen that too when the weather gets a bit warmer and more humid.

Drew Pojedinec

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Re: Tune Changed Overnight
« Reply #2 on: June 14, 2019, 09:26:41 PM »
Today I go for a ride and it seems rich, idles a couple hundred higher, bogs, and runs on when shut off.  What happened?

Do you have a choke?  Is the fast idle screw hanging up and keeping the primary open a tad?

427LX

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Re: Tune Changed Overnight
« Reply #3 on: June 14, 2019, 10:07:18 PM »
What springs are you running in the Vac. Secondaries? Could be maybe the secondary throttle plates cracked open a little due to using the light spring. Check and see if there is any movement between secondary shaft and end link when throttle is closed.

superduty

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Re: Tune Changed Overnight
« Reply #4 on: June 14, 2019, 10:23:51 PM »
Distributor roll pin?  Timing chain or gear?

Chrisss31

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Re: Tune Changed Overnight
« Reply #5 on: June 15, 2019, 06:17:18 AM »
What are you using for a fuel pressure regulator?  I used to run a race car that had a single fuel line to one of those cheap diaphragm regulators.  During the day I'd have to crank it all the way in to get adequate pressure, if I left it alone when it cooled off at night it had enough pressure to overcome the inlet needle.  I ended up putting a fuel log with a return line.  This was a sprint car with a motorcycle engine so I'm not sure if it would apply to you, just thinking out loud.

Thumperbird

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Re: Tune Changed Overnight
« Reply #6 on: June 15, 2019, 07:52:38 AM »
Temp was maybe 5 degrees cooler, humidity up a bit
No chokes or linkage
Mechanical distrib. just switched to blue bushing, ble/blue springs (MSD billet)
All new internals.
Timing is 16 initial
Fuel level good in bowls, not running regulator yet, gauges show 5.5psi
Quick Fuel slayers, vac. advance is screw adjust, out about 3.5 turns
I exercised the secondaries on several runs, maybe one of them hung up a little or something.
Primaries are closed off, secondaires used to set idle.
Thanks.

Drew Pojedinec

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Re: Tune Changed Overnight
« Reply #7 on: June 15, 2019, 09:42:57 AM »
If the secondary plates are sticky at all, or hang up in the bore, running hard and opening them will leave the idle high since they may not shut all the way.
I had a QF do just that.  650rpm idle in gear, go for a spirited ride, and couldn't get idle under 1,000.

For the moment I bent the secondary link so it pushed the secondary plates closed.  Ultimately I had to reposition the secondary plates so they could close smoother.

machyoung

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Re: Tune Changed Overnight
« Reply #8 on: June 15, 2019, 09:50:19 AM »
Black smoke out the tailpipe? Sure sounds like fuel? Leaking past the fuel inlet valves? I'm sure you double checked the timing?

machoneman

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Re: Tune Changed Overnight
« Reply #9 on: June 15, 2019, 10:35:19 AM »
If rich, check that the o-rings on each needle/seat assembly haven't shrunken, allowing gas to pass, the gas going into the venturi wells.

Happens a lot now with 10%+ ethanol gas. Easy way to to tell: pull each assembly straight up. There should be drag due to the synthetic rubber o-ring rubbing on the interior wall of the float. Another way is to eye-ball how far the o.d. of the ring sticks out from the brass body compared to a new o-ring mounted on another assembly. 

Btw, the bad part here is that the o-ring doesn't fail quickly. It does so over time and can be hard to detect until a lot of gas starts creeping past the ring. 
Bob Maag

Thumperbird

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Re: Tune Changed Overnight
« Reply #10 on: June 15, 2019, 11:50:24 AM »
As usual a lot of great responses, thank you all.

Timing was checked, same.

Carbs are new, I looked them over before installing and must admit did not love the way the butterflies sat in the bore closed.  Thinking I am going to pull carbs and more meticulously go through the shafts, butterflies, etc..
I almost feel like a very slight rounding of the plates might be best to get a consistent seat in the bore.
Don't think it is needle and seat, fuel levels seem fine and like I said, new slayers.
Might deburr all linkage and sliding surfaces, seems factory finish is not the best on all of the little widgets and it makes for less than perfectly smooth mechanisms.

I'm finally getting what Drew and others always insist upon with duals, you can not be too careful and meticulous when setting them up, everything needs to be gone over and massaged so to speak to get dead on adjustments and consistency in operation.

Forcing me to be a carb guy I guess, I need to own them and make them do waht I want.

Thanks.

Drew Pojedinec

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Re: Tune Changed Overnight
« Reply #11 on: June 15, 2019, 01:45:59 PM »
I almost feel like a very slight rounding of the plates might be best to get a consistent seat in the bore.

I'm finally getting what Drew and others always insist upon with duals, you can not be too careful and meticulous when setting them up, everything needs to be gone over and massaged so to speak to get dead on adjustments and consistency in operation.

The old ones had plates that were shaved perfectly to fit in the bores :P  The secondary plates on a C3AE-C carb is a fine and common example.  Please do not shave your own throttle plates :P  Way easy to get off base.

To the second point.... once you really and truly get these reigned in, they will be good forever.  Aside from pulling the carb off my truck in order to test other folk's stuff, I honestly haven't been into it or made an adjustment in years.

Thumperbird

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Re: Tune Changed Overnight
« Reply #12 on: June 15, 2019, 02:32:51 PM »
Hoping that is the case before too long here, don't mind tinkering but don't like redo's.
As for cleaning up the mechanics, I am sure I could screw it up and maybe will but my day job has me dealing with fine fixtures, microns of material removal, polishing, all kinds of very high accuracy playing on equipment, hoping that keeps me out of too much trouble.  Leds is more, I get it and thanks for the warning and feedback, much appreciated sir.


67GT500

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Re: Tune Changed Overnight
« Reply #13 on: June 15, 2019, 05:39:43 PM »
I would check for a leaking power valve.. I had this happen the other week.. they were fairly new valves, but all of a sudden i was having all sorts of issues.. pulled the carbs, broke them down and found the secondary carb had a wet power valve chamber.. I tested the valve and it held on a vacuum test, but i replaced it and we were all set again.running great..

Barry_R

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Re: Tune Changed Overnight
« Reply #14 on: June 15, 2019, 07:00:02 PM »
Throttle plates "used to be" machined with a 7 degree taper on the O. D., and closed throttle airflow was set on an orifice box after assembly.  No idea what is done nowadays, but I would bet it ain't "better"....

Thumperbird

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Re: Tune Changed Overnight
« Reply #15 on: June 15, 2019, 07:40:47 PM »
Bingo Barry!  Here's the latest, solicitiing some more feedback for a couple new observations also.

Pulled the carbs, you can tell the plates are just stamped, they don't exactly stick in the bore but not smooth either.
Cleaned up all plates, smooth as butter seating perfectly now every time, set primary slots to just barely see them, made sure they are equal, they were off say 0.015" one to another.  There was a little flash at the edges of the bores for the throttle shafts, cleaned that up.  Used secondaries to set idle.  Idle screws at about 5/8 turn out

Test drive was fun as ever!  Lots of power, not near as rich at cruise, nice steady 12.5 a/f at idle, 14 to 15 a/f at cruise.
Huge improvement over the way they were even before thy changed.

Now here is where the fun begins:
Question 1 Bottom end is stronger if I leave the pcv disconnected and bleed air into the base of one of the carbs, thoughts on this?  No baffle in valve cover so I know I am pulling a little oil into the intake.

Question2  I noticed a few days back a light tick when cold, went away when warm.  Today after my 3rd or 4th launch and first succesful 6000rpm strong pull she was ticking like crazy, running a hair rough at idle.  By the time I got home it had cleared itself, I suspect this is a sticky lifter?  They are morels.  Thoughts on this.
« Last Edit: June 15, 2019, 07:45:54 PM by Thumperbird »

Thumperbird

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Re: Tune Changed Overnight
« Reply #16 on: June 15, 2019, 07:48:21 PM »
So, by the way, thank you Drew, Barry, Battlestar G. and all the rest for all of the input on how to run duals, very helpful, would not have gotten to where I am without you guys, much appreciated!  She scares me now up near 100, the front of the big bird likes to float around but sure is fun geting there!

Drew Pojedinec

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Re: Tune Changed Overnight
« Reply #17 on: June 15, 2019, 07:52:46 PM »
Question 1 Bottom end is stronger if I leave the pcv disconnected and bleed air into the base of one of the carbs, thoughts on this? 

Since you are officially a carb tuner now  :P  I'll toss it back to you.....
why do YOU think unmetered air is making your engine run strong down low?

Drew Pojedinec

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Re: Tune Changed Overnight
« Reply #18 on: June 15, 2019, 07:55:52 PM »
and yeah, I've said it before, but I'll say it again....
on a 2x4 set of carbs, when everything is restored, I have it all laid out, and I go to assembling, I spend about 1.5 hours assembling the baseplates.  I only spend an hour assembling the rest.  It matters.

427LX

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Re: Tune Changed Overnight
« Reply #19 on: June 15, 2019, 07:57:21 PM »
Tbird..glad you got it straightened out! I built up my Holley dual quad setup from scratch and run a much retuned 660 Center Squirter as the secondary carb and a 650 VS as the primary carb which handles cruising on the primary only.
The FUN begins past 40% travel!!! Works like a champ!


Those jet numbers are all 68
« Last Edit: June 15, 2019, 08:03:30 PM by 427LX »

Thumperbird

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Re: Tune Changed Overnight
« Reply #20 on: June 15, 2019, 09:03:48 PM »
Nice setup 427lx, I see you cut the horn off the main, I may go at mine this winter.
Drew still a hack of course but learning.  Not sure on the unmetered air, it did run a bit leaner of course so I had the idle screws out another 1/4 turn and cranked the secondaries closed a bit for idle rpm.  The thing has always liked a little bleed down low, are they all that way?  I wish I had a nice technical spot on answer but nope. 

cammerfe

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Re: Tune Changed Overnight
« Reply #21 on: June 15, 2019, 09:10:13 PM »
I would check for a leaking power valve.. I had this happen the other week.. they were fairly new valves, but all of a sudden i was having all sorts of issues.. pulled the carbs, broke them down and found the secondary carb had a wet power valve chamber.. I tested the valve and it held on a vacuum test, but i replaced it and we were all set again.running great..

Plus one on the faulty power valve. I had an experience such as yours on my 'two-days-past new-delivery' '64 Custom/427. I'd had dual quads on my previous car, a '54 Customline/312 but those are completely different carbs. The '64 was my first experience with the 'new' Holleys.

I went back to the dealer and their resident carb expert, called 'Tiger', knew right away what was wrong. The rubber was all blown loose on one side of a power valve. Replaced within about 15 minutes and I was good to go.

At one time I'd accumulated a whole bunch of miscellaneous Holley parts, but when Holley came out with their 'bolt-on' EFI, I made the switch. Haven't owned a carburetor for more than 20 years now. :)

KS

Drew Pojedinec

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Re: Tune Changed Overnight
« Reply #22 on: June 15, 2019, 11:57:10 PM »
Drew still a hack of course but learning.  Not sure on the unmetered air, it did run a bit leaner of course so I had the idle screws out another 1/4 turn and cranked the secondaries closed a bit for idle rpm.  The thing has always liked a little bleed down low, are they all that way? 

Still a hack here as well, I just put a lot of hours into it all :P
If nothing else changes and you add air, if it runs better it was too rich before.

If you are inducing an air leak and compensating by trying to richen it up, well.... don't.

You have an O2 sensor, and that is handy, but engines are gauges for these things too.  If you hang around engines often enough and listen, you can hear lean and rich.  Lean is super easy to notice at cruise and idle.  Richness less so, but the word "fat" sure does seem to sum up how it feels/sounds.  A lot of folks are used to how an overly fat carb runs on an engine, the first time you feel it right where it needs it to, it is liberating, the clean feeling the engine has at power, etc.

I have had so many people bring me carbs that didn't run right I've lost count.  That said, I've seen 1 blown power valve in my life.  Either way, it takes 5 seconds to check, just fill bowl with fuel and look at the bottom of the carb, is it leaking out of the PV signal hole?  yes/no?  In my limited experience I've seen plenty of power valve gaskets that leak, but yup....1 blown PV.  I often wonder why so many other people have blown pv's?  A mystery for sure :P

wowens

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Re: Tune Changed Overnight
« Reply #23 on: June 16, 2019, 07:14:00 AM »
and yeah, I've said it before, but I'll say it again....
on a 2x4 set of carbs, when everything is restored, I have it all laid out, and I go to assembling, I spend about 1.5 hours assembling the baseplates.  I only spend an hour assembling the rest.  It matters.

I hope you are available when I get to the carb phase .
Woody

Thumperbird

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Re: Tune Changed Overnight
« Reply #24 on: June 16, 2019, 08:24:48 AM »
Wowens all I can say is if you carbs have never been massaged by the likes of Drew or others don't bother installing them without going through them first and making sure they are smooth and repeatable mchanically and plates are positioned identically in the bores.

Still need to play to get to the sweet spot a/f wise but geteting closer now.
Any way I can deal with a stuck lifter without taking the top off if it happens again?

Tahnks again all.

My427stang

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Re: Tune Changed Overnight
« Reply #25 on: June 16, 2019, 09:53:13 AM »
Is this a hyd roller motor?  They can be fussy on oil viscosity. 

Of course that is a comment on the noisy valvetrain not the carbs :)
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Drew Pojedinec

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Re: Tune Changed Overnight
« Reply #26 on: June 16, 2019, 10:09:57 AM »
I hope you are available when I get to the carb phase .

You live 100 miles due north of me.....  just stop in :P

Barry_R

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Re: Tune Changed Overnight
« Reply #27 on: June 16, 2019, 11:17:39 AM »

That said, I've seen 1 blown power valve in my life.  Either way, it takes 5 seconds to check, just fill bowl with fuel and look at the bottom of the carb, is it leaking out of the PV signal hole?  yes/no?  In my limited experience I've seen plenty of power valve gaskets that leak, but yup....1 blown PV.  I often wonder why so many other people have blown pv's?  A mystery for sure :P

Lots of folks blame the power valve for their problems - but they do not fail very often at all.

The power valve resides in a cavity right below the accelerator pump transfer passage.  A good backfire can pressurize that cavity and compromise the gasket seal below the pump passage.  Especially in situations where the gasket surfaces are not flat as a result of bowl over tightening and heat cycles.  The gasket failure allows fuel from the pump to get sucked into the vacuum in the cavity, and it runs poorly followed by a dead hole from the now dry pump.  Replace the gasket when replacing the assumed "bad" power valve and everything is "fixed' until the next time.

Holley was aware of this issue decades ago, and some carbs had a pump transfer tube that was sealed by o-rings - - - bean counters eventually killed that good idea.

Thumperbird

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Re: Tune Changed Overnight
« Reply #28 on: June 16, 2019, 04:58:46 PM »
Hydraulic roller, Harland Sharp rockers and Morel lifters.  Running 10w-30 VR1.
Just went for another drive and ticking again after 6000 rpm run, frustrating, did not clear by the time I got home today.
At least the tune has been stable for a couple days now.

My427stang

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Re: Tune Changed Overnight
« Reply #29 on: June 16, 2019, 07:55:54 PM »
How much preload did you set it up with? What are you seeing for oil pressure?

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- 71 F100 shortbed 4x4, 461 cid FE, headers, Victor Pro-flo EFI, Comp Custom HFT cam, 3.50 9 inch

Thumperbird

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Re: Tune Changed Overnight Found It!
« Reply #30 on: June 17, 2019, 06:52:48 AM »
Aluminum heads, I went 1 full turn on the Harland Sharps which I believe is 0.050".
Oil pressure is very good, 20+ hot at idle, 50 crusie, over 60 cold or on it.

Maybe pre-load was too much and I managed to jamb a lifter piston in it's bore due to some valve float or ?

Ran it gentle some last night and pretty loud tick still there, hoping it goes away as I would prefer to drive it easy (so it does not happen again) for a while before having to pull the top off.
Thanks.
« Last Edit: June 18, 2019, 05:33:20 PM by Thumperbird »

blykins

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Re: Tune Changed Overnight
« Reply #31 on: June 17, 2019, 08:34:32 AM »
Aluminum heads, I went 1 full turn on the Harland Sharps which I believe is 0.050".
Oil pressure is very good, 20+ hot at idle, 50 crusie, over 60 cold or on it.

Maybe pre-load was too much and I managed to jamb a lifter piston in it's bore due to some valve float or ?

Ran it gentle some last night and pretty loud tick still there, hoping it goes away as I would prefer to drive it easy (so it does not happen again) for a while before having to pull the top off.
Thanks.

One full turn is generally .050-.060" of preload which is fine.  You don't have too much preload. 

What oil are you running?  Are you sure it's not a header gasket leak?
Brent Lykins
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Thumperbird

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Re: Tune Changed Overnight
« Reply #32 on: June 17, 2019, 12:06:59 PM »
Pretty certain it is not a header gasket, felt around and the sound is distinctly a metal tick.
10W-30 VR1.  Oil pressure is very good, 20+ hot at idle, 50 cruise, over 60 cold or on it.

It happened the other night after a hard run as well but went away in a few miles, this time, I have run it for a few more minutes but no improvement yet.  It is off enough where I can tell idle is not the same.

« Last Edit: June 17, 2019, 12:17:13 PM by Thumperbird »

Thumperbird

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Re: Tune Changed Overnight
« Reply #33 on: June 18, 2019, 10:01:50 AM »
I suppose a real engine builder would have disassembled, inspected , and cleaned up a new set of lifters before installing.
I was not that smart.  Am I missing something here?  If it were bent valve it would not have gone away the first time correct?

RJP

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Re: Tune Changed Overnight
« Reply #34 on: June 18, 2019, 10:59:26 AM »
Intermittent lifter ticking after a hard run can be oil aeration. Check your pan for correct capacity, proper baffling and pump pick up [cracks, pinholes etc]. And don't overlook the pickup to pump flange gasket.

Thumperbird

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Re: Tune Changed Overnight
« Reply #35 on: June 18, 2019, 01:42:18 PM »
How nervous/cautious should I be about running it with a pretty loud tick?

MRadke

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Re: Tune Changed Overnight
« Reply #36 on: June 18, 2019, 02:25:44 PM »
When mine had a tick after I drove it enthusiastically, it had a bent push rod.  Costs a set of valve cover gaskets and some time to check.

HarleyJack17

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Re: Tune Changed Overnight
« Reply #37 on: June 18, 2019, 03:02:17 PM »
If it has a pretty good tick it is time to investigate as stated above.
Was the dizzy gear the correct type for a roller cam and set correctly? Bent/loose pushrod? Cam bolt the correct threads and get Loctite at assembly(some roller cores differ)? Lifters installed in correct direction with link bar toward the center of the block?

I would investigate the above items, all easy to do, with the exception of the cam bolt...but likely you remember if you put the correct bolt and put thread locker on it.

Unfortunately, I put together a new stroker and it dropped a lifter. Investigation found a collapsed lifter, and two damaged lifters.  The result of the dizzy gear being set up wrong and cam bolt was backing out(forgot Loctite).  Rookie late night mistakes but it happened, even after several checks and thought processes.  Check lists will be used on the next one.

It may just be a bad lifter or maybe a loose pushrod, but with what these engines cost, I recommend digging into it a little in case it is a major issue.  Hour or two just to put your mind to rest and maybe save from an expensive fix if left undone. Best of luck.
 

Falcon67

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Re: Tune Changed Overnight
« Reply #38 on: June 18, 2019, 03:23:35 PM »
Just throw in a couple of comments -

1) in my experience, if a dual primary only idle type setup isn;t set spot identical, you can get random issues like rolling idle, etc.

2) Power valve gaskets leak.  10% ethanol, VP racing fuel, whatever - the current crop doesn't last long.  I regularly pull them out looking like a soaked rag or they come apart in two layers, like a cheap bagel. 

3) those that commented on  changing weather - from my experience running carbs, bah.  We can get 2000+ ft of DA change in a day at the track and nobody goes around fiddling with carbs or injectors, etc.  We went from around 3800 at 8AM to near 6000' on Sunday then dropped to close to 3500 because of air from close thunderstorms.  Nobody took a screwdriver to anything.  If you get carb issues when the temp changes 10 degrees, you are either way, way, way too lean or you have other issues.  We'll lose over 4000' effective altitude between here and Dallas and not re-jet.  The cars just pick up .2~.3 and maybe a couple MPH in 660'.  Methanol, maybe .1.  IMHO carbs are not that sensitive.  Engine power output IS - but not the carbs.  You lose power from water grains displacing air molecules or heat reducing the weight of the air stack resting over the carb. 

Thumperbird

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Re: Tune Changed Overnight Found it!
« Reply #39 on: June 18, 2019, 05:29:43 PM »
Collapsed exhaust lifter on #4.  Have not pulled intake yet but a solid 0.075" of pushrod play, adjuster is tight and has not moved, so hoping that is all it is at this point.  I guess i know what I will be doing next.

Barry_R

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Re: Tune Changed Overnight
« Reply #40 on: June 23, 2019, 06:06:03 PM »
Dual quads.  You can probably fish that lifter pair out through the rear breather opening without pulling the intake.
Tag wire with a little hook bent into it, a flashlight through the distributor hole, long needle nose....alcohol....

Drew Pojedinec

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Re: Tune Changed Overnight
« Reply #41 on: June 23, 2019, 08:06:12 PM »
Dual quads.  You can probably fish that lifter pair out through the rear breather opening without pulling the intake.
Tag wire with a little hook bent into it, a flashlight through the distributor hole, long needle nose....alcohol....

Not naming any names (it was me), I know a fella that installed the intake on an engine stand, got everything sealed up, was getting ready to install the pushrods and rockers, etc and decided to roll the engine over on the stand.  That guy is a real idiot, but he got good at installing lifters with the intake bolted down (again, this was me).
Same guy that stuck a screwdriver through the flexplate so he could torque the balancer bolt.  He later forgot about the screwdriver and panic'd when he could only turn the engine over so far either way. (also me)

67428GT500

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Re: Tune Changed Overnight
« Reply #42 on: June 23, 2019, 08:45:11 PM »
Drew.... Say it's not so!  ;D ;D ;D ;D ;D

                                  -Keith

Thumperbird

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Re: Tune Changed Overnight
« Reply #43 on: June 24, 2019, 06:46:30 AM »
Thanks all. 
Swap is done, lifter definitely stuck down hard, 100psi (input) did not free it up but a solid wrap on a hunk of wood did make it move.  I wanted to get a look at the other lifters and cam lobes so the intake came off, good practice.  Outside of fighting to crack valve covers loose, used Permatex black ultra, the stuff is nasty to work with but does not let me down, and arduous clean up of gasket surfaces, did not go too bad overall.  Cam lobes, other lifters, dist. gear, rod ends, rockers, etc., all look good.  Good news is after shimming the rocker stands over the winter rocker sweep on the valve tips is down to ~0.050".

I still have a light tick somewhere though I have a hard time discerning it from normal engine noise and don't really know what "normal" is anyways, not going to worry about that for now and just get some miles on it, probably set my rev. limit idiot light at 5500 and not delay shifts.  I was into the low 6's and either MSD rev. limit had kicked in or the valve train was misbehaving at the end of the run that toasted the lifter so no more rpm's over 6 for a while.

Has anyone ever experienced high rpm's cause so much coolant hydraulic pressure/flow that it bends the flange of the thermostat, has happened twice to me now.  The way the thermostat sits in the expansion tank neck the entire diameter of the flange is not pinched between solid surfaces.

Thanks. 
« Last Edit: June 24, 2019, 06:55:33 AM by Thumperbird »

Falcon67

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Re: Tune Changed Overnight
« Reply #44 on: June 24, 2019, 08:26:01 AM »
Good news there.

My experience with water pumps and higher RPM is not pressure, its that they get into cavitation and lose flow.  Even the Flow Kooler units that use the disk on the back of the fins to improve flow do it.  If pressure is going up, then my guess would be steam pressure, maybe from steam bubbles around the chambers in the heads.  I run at least 16 PSI and sometimes 22. 

Check exhaust gasket area closely for your tick.  I swore the 351C in the Mustang had a solid lifter sound out of the hydro rollers until I noted that the Percy's exhaust header gaskets were leaking nearly everywhere.

>Tag wire with a little hook bent into it, a flashlight through the distributor hole, long needle nose....alcohol....
Probably not talking about denatured either...  ;D