All out of tricks, breaking up 5300

[SPOT MY 6]

Disconnect your fuel pump and run the car till it dies. Pull the valve covers and have someone crank the motor. Watch each rocker as it is cranking to make sure the valves are opening all the way.

I have a 212/212 billet roller in my car and it has been to 6500rpm.

Check the power wire going to your starter and make sure it isn't grounding itself out somehow. Mine was grouning on to the starter heat shield causing the same thing at higher rpm (must have been the vibrations). Was smooth at low rpm, but once it got into the 5k range it sputtered.

What kind of miss are you getting? Pop through intake? Pop through exhaust? Which sensor spikes first when you look at your FAST logs? (RPM, A/F, IAT, ?) Look frame by frame to see which one moves first.

 

[Jerryl]

Does this seem like a sudden electrical type cut-out?
I heard of someone collapsing the intake tube and/or air filter. Not sure if this makes sense in your case, but, just another brick in the wall.

 

[Alaskabuick]

Does this seem like a sudden electrical type cut-out?
I heard of someone collapsing the intake tube and/or air filter. Not sure if this makes sense in your case, but, just another brick in the wall.

It is very smooth and just sounds like the motor is hitting a very smooth revlimiter? Get kind of a loud valve terrain noise? Soon as I shift the car rips!

I have a solid intake tube, so dont think that could be an issue.

thanks,

Dennis

 

[AKTURBOTA]

Dennis,

Sorry to hear about your problems...I was going to suggest the collapsed intake tube...I had a similar problem with my 91 Syclone.

Mark

 

[Alaskabuick]

Hey Bro

Dennis,

Sorry to hear about your problems...I was going to suggest the collapsed intake tube...I had a similar problem with my 91 Syclone.

Mark

Mark,

Well the I cant say I am dissapointed, the car is spinning M/T drag radials at 70, but just that last 500 rpm I am breaking up.

Without a doubt it would run a good number as is, but still not 100%.

Ill figure it out, gives me something to do.. haha..

Maybe Ill drag the Wagon down in the next couple weeks to run in Palmer.

Dennis

 

[Alaskabuick]

great improvement

I think I got it!

Was at my wits end with this car Breaking up at 5300.


Well I should of listened to my 1st gut instinct. I Thought it was the lifters but most I talked to said it was not.

Switched to comp 885 hi rev from the 853's PROBLEM SOLVED! snaps right up to 6k rpms in a instance. Spent a bunch of wasted money on other things guessing at it. But seems to be doing a heck of alot better now....

Seems to pull real strong up to shift points, still seems to get a loud valve train noise at around 5500 but nothing like it was doing before.

So getting closer.

Dennis

 

[AKslowNeon]

alaskabuick I know we have our issues but this is a common problem with the SRT-4 using aftermarket engine management systems (AEM EMS/ SOME SAFCII's some DTEC's and so on so forth.)

we have tried nearly everything and nothing solved the break up issue (5800-6100 rpm)

after pondering this with a few other shops we came to the idea of scoping the injector pulse.. low and behold.. thats what it was some of the factory ECU's were freaking out at 5800-6100 (just a weird issue that only effected some cars.) it would hit a select RPM then go haywire where we would loose voltage to the injector(s) usually #3.

swapped ECU's and it fixed the issue (sounded like the same thing your talking about in a sense where you would hear valve noise, soft to mid range rev limiter and so on...)

just an IDEA for you to ponder

 

[Alaskabuick]

Ecm

Ryan,

I have a fast system and the factory ECM is completly gone and been replaced with the wide band. At this point I am up for trying anything.

I tried new high rev lifters and that seemed to help some but not fix it.

Maybe you guys know some magic I dont? I am new to all of this being a old school guy.

As far as issues go, its all for the fun man.


Thanks,

Dennis

 

[AKslowNeon]

Ryan,

I have a fast system and the factory ECM is completly gone and been replaced with the wide band. At this point I am up for trying anything.

I tried new high rev lifters and that seemed to help some but not fix it.

Maybe you guys know some magic I dont? I am new to all of this being a old school guy.

As far as issues go, its all for the fun man.


Thanks,

Dennis

Dennis what are you doing thursday (im off from work) I can swing by and possibly help you with some sport compact thinking as we are a little more used to the stand alone systems

 

[AKslowNeon]

also what plugs are you running? we had a sim. issue running some champs we switched to the NGK Iridium 9s and it solved that issue on a customers car

 

[Alaskabuick]

plugs

Tried some NGK's did not change issue. Tried to tighten up the gap to 28thous, on and on.

Thanks for the kind offer Ryan, But I dont think thrusday would work, have a buddy installing some shims on the valve springs. Found out that the springs were installed too loose, so need to shim 60thous? Not sure it will fix the problem but, process of elimination and does need to be addressed.


Ill keep you posted,

Hey, you know SGT MAJ Bean?

Den

 

[AKslowNeon]

Tried some NGK's did not change issue. Tried to tighten up the gap to 28thous, on and on.

Thanks for the kind offer Ryan, But I dont think thrusday would work, have a buddy installing some shims on the valve springs. Found out that the springs were installed too loose, so need to shim 60thous? Not sure it will fix the problem but, process of elimination and does need to be addressed.


Ill keep you posted,

Hey, you know SGT MAJ Bean?

Den

ok keep me posted so i can hopfully help you eliminate this issue. as for SGM bean no clue who he/she is

 

[Mike Licht]

how much preload on the lifters?

 

[bad_news]

Rpm Breakdown

Had A Similar Problem 2 Years Back; One Of The Ground Wires On The Back Of The Right Cyl Head Had Pulled Free From Its End Ring. Car Would Run Up To 4800 And Start Bubbling, Took Weeks To Find The Problem.

 

[Alaskabuick]

preload

how much preload on the lifters?

Sorry for the late reply Mike. The preload is at .007, I have just done a search and seen where you reccomend .003 on the 885 lifter.

I have one other issue, the springs were installed wrong and need to be shimed to meet the the specs from comp on coil bind.

From what I understand they need to be shimed up .090ths to meet the proper installed spec. We are going to go with .060ths as that is a standard shim.

Any recomendations?

Thanks in Advance.

 

[turbocaddy1982]

read my rev limiter type problem i posted with my car....oil pressure switch solved it...15.00 dollar part..after spending hundreds....

 

[Alaskabuick]

shims

Finally got it 100%,

Valves were installed with not enough too far from coil bind, installed 60 thou shims and set lifters a .003 preload.

Runs like a raped ape...

 

[Jerryl]

Finally got it 100%,

Valves were installed with not enough too far from coil bind, installed 60 thou shims and set lifters a .003 preload.

Runs like a raped ape...

Good to hear! I think you mean 0.030" (??)
Time to get her ready for "that" run. :wink:

 

[AKTURBOTA]

Finally got it 100%,

Valves were installed with not enough too far from coil bind, installed 60 thou shims and set lifters a .003 preload.

Runs like a raped ape...

Dennis,

Good to hear you are running like you expected. Have you been to the track? Are you going to come done for the Labor Day races?

Mark

 

[Alaskabuick]

Good to hear! I think you mean 0.030" (??)
Time to get her ready for "that" run. :wink:

I am runnig comp 885' hyd roller lifters, .003-.007 preload is what I was told. Works good and not loud at all.

Den