Car cuts out at high rpm

[Lit549]

Heres my setup, smeding 383(450hp) with pertronix ready to run billet ignitor iii ignition. Carb is a proform 750vs carb.
Im having 2 issues, at high rpm it starts cutting out like the rev limiter is being engaged. The distributor has the ignitor iii module with digital rev limiter. The 1st module would not adjust with there procedure, it was stuck at 5500rpm limit. I replaced the module, the new would set just fine to my 6500 rpm limit. The car was still cutting out at 5500rpm so i turned the rev limit off completely and it STILL cuts out at high rpm.
it seems to rev higher now but it does cut out still, at what rpm i have no idea because my new tach WILL NOT go above around 5500 rpm. I have correct voltage to the coil, tach is wired correctly per their instructions. Could i be having a voltage issue because if where my coil is mounted(on aluminum intake)??? Im stumped, i have no idea why it breaks up at high rpm.

[fatguyzinc]

my guess either valve float or running outta fuel.

[Lit549]

Im wondering if it is actually floating the valves? With the tach not reading right it may actually be turning over 7k, idk, doesnt feel like it is.

[anotheridiot]

Where is your power coming from, a clean ignition source or the standard GM on the starter solenoid? Every time I had a cut out ignition issue it was because of that coil wire coming from a smoking hot starter solenoid from exhaust heat.

If its mechanical I would look at the distributor shaft possibly having a wobble and when its up that high the space to the module closes. It might never be a problem until it starts spinning that fast. Thats what you get from these companies buying parts from China. I am sick to my stomach getting some control arms for the Camaro and they show up from Johnny Law, talking all about CNC manufactured, OEM ball joints and bushings blah blah blah and come in a made in china box.

But all that aside, valve springs sound like a problem, buy I would think you would hear something or be burning up a plug if you are sucking exhaust gas into the intake and vice versa from floating.

[Lit549]

I used the factory pink ignition wire, i verified yesterday it has 12.8 volts.. I also tore apart the tach and made sure it is set to 8 cylinder setting and that its getting correct voltage, which it is. I ran the tach signal wire to the negative side of coil per instructions.. I really think it just wont go over 5500 rpm, and im suspecting the module rev limiter. I readjusted the module to 7400rpm so ill try her again today. On the fuel side its 12.5 at wot and stays there, its a in tank holley fuel pump

[Lit549]

Well i reset the rev limit to 7400 and went for a test drive, i also went up one jet size to a 83 in the secondary, car didnt cut out at 5500rpm♂️.. I didnt turn it much passed that like maybe 5700rpm. Ill see if it stays that way. I really think the pertronix ignitor iii has been the issue.

[fatguyzinc]

Well i reset the rev limit to 7400 and went for a test drive, i also went up one jet size to a 83 in the secondary, car didnt cut out at 5500rpm♂️.. I didnt turn it much passed that like maybe 5700rpm. Ill see if it stays that way. I really think the pertronix ignitor iii has been the issue.

ah yes, my old nemesis. my younger brother and i did a 69 lincoln 460/c6 into an 86 fox mustang,
it was GNARLY. car kept unexpectedly dying leaving him stranded, ended up being pertronix ignitor.
they warrantied it....the first 3 times. after the 4th time (all in 6 months) it went in the trash and a
davis DUI/HEI conversion went in, car never had any problems after that for the 5 years he ran it
as a daily plus weekend warrior.

there are several big name items i absolutely will not run on my cars, EVER--and the pertronix ignitor
is one of them.

id sooner run points.

[Lit549]

ah yes, my old nemesis. my younger brother and i did a 69 lincoln 460/c6 into an 86 fox mustang,
it was GNARLY. car kept unexpectedly dying leaving him stranded, ended up being pertronix ignitor.
they warrantied it....the first 3 times. after the 4th time (all in 6 months) it went in the trash and a
davis DUI/HEI conversion went in, car never had any problems after that for the 5 years he ran it
as a daily plus weekend warrior.

there are several big name items i absolutely will not run on my cars, EVER--and the pertronix ignitor
is one of them.

id sooner run points.

Im learning that! I use to run Msd and really never had any issues but the quality seemed to go down hill. I may look at Davis, see what they offer..