no RPM

Hey silverfox uhm in a way yes it is running through the converter...I'll hold the brake pedal and flat foot it to 3800rpm before the wagon starts to lock up and move.....my engine should be about 6500 rpm.....but I can't get it there.....and you are prob. right about the manifolds.....I am putting alot of air and fuel into the cylinders and it's probably causing a reversion and not getting out fast enough.....causing the engine to choke. but I still should be getting at least 5000 rpm......5500......

 

You could break the pipes loose at the manifolds and see if there is any improvement. That would tell you if the exhaust is the problem. :confused:

 

sorry but no

unless the exhaust is plugged up.......

an all stock exhaust would not stop the engine from rev'in; it would just be down on power but would not stop at some mystery 4000RPM wall.
It would still rev out, probably slower then usual but it would not just stop.

 

I'd put an advance timing light on it at the very least.
Maybe it's not getting full advance.

 

With his MSD parts make sure and use a standard inductive timing light, not a fancy digital one. The dual spark of the MSD will not read right with a digital.

 

MSD? Rev limiter on it?

 

Sometimes, dunno what all he has.


My MSD box come with pills to set a rev limit, though I don't have any installed.

 

I wasn't aware that it hit a "mystery wall" at 4K. I thought it was just slow revving and was at about 4K at the end of the run. I had a BB that did that and it was the due to the stock manifolds. That mystery was solved with headers.

 

What it sounds like or reads to me, he can't go over 4000, it should rev to redline and beyond, just might be slow. He may need to clarfyi that.
Will it go beyond 4000 or not, it should be able to over rev n blow, even with low flow.

Had that problem with my V6 Firebird once too, I made a side dump for it that was cool but I totally lost all my hi end power, just didn't rev out like it would before, but would still rev. Knocked a hole in the 90* turn out I used, so it also blew straight out and rev'ed fast n hard to redline again.

 

You did lose the heat riser, didn't you? From what I gather, it will rev OK in neutral, but under load falls on it's face @ 4000. I am not a fan of MSD stuff, but I feel this is an exhaust related problem.

 

Really? I've got a timing light with the dial that lets you advance or retard the timing....and I do have full advance at 3000 rpm.....34 deg.

 

Yep, its all over the MSD tech forum when looking for info about mine.

1st thing I learned is that the wires come out of different ends of the box for a reason and when I bundled them all together it was a no no. [cross talk]

2nd was that, to use the cheap inductive timing light as the dual spark messes up the fancy digitals.

 

Thinking about it I have had bad wires do that, car would rev fine in the drive way but not go over 3500RPM in gear, first thought it was the coil, I could see spark leaking out the side of it when the hood was open in the dark.
But after 3 coils went bad real quick, I changed the wires and it was all better. The wires were not old enough to make me suspect them.

 

ok let me clarify some things.........the engine is a 400 ford block.....the heads are 1972 HO cleveland.......ported that flow 357 on the intake and 207 on the exhaust they are an open chamber boss head.
the block is 30 over
boss 351 domed piston full foating pins.
rods are stock 400 that have been bushed at the small end and shot peened and pollished
the crank is stock that has been hardened.
oil ristrictor kit installed. and I have a external oil line as well
the cam is a custom comp 224-236@50 with 624-636 lift mechanical roller.
173 roller rocker 3/8 push rods
PME spacers and a torker intake.
compression is 10.75-1
and a full 2 1/2 in exhaust with flow master 40 mufflers.
and the MSD 6al with a billet dist. there is no pill in it.
this thing should make 600 horse power all day.
it was designed on a computer and I just don't get it.
C6 trans. 4000 converter 389 gears. all in a 5000lbs CS.
in neutral it will rev to 6500 but slow. in drive it wont.

at the track I flat footed it to a 15 sec flat with a 19 60 foot. the car would rpm till 4000 struggle to 4400 where I'd shift it. even in drive didi the same thing shifted struggling at 4400rpm.

I have a set of hooker super comp headers 2in primeries and 36 in long. but they are from a 71-73 mustang and hit the upper frame just below the upper control arm.....thinking of notching the frame there to clear.

 

I would modify the headers before I notched the frame..