max rpm's 6300 ???

[captmullette]

I put my old dirt track motor in my 31 ford bracket car, 355 sbc iron double humps small valve , flat top pistons, REED 3/8 mile dirt track cam, my partner cant find my cam card....this motor was built around 85/86 and sat in the back of a truck for 20 something years, rockers were loosened double springs all old and original.......my question is could I be running out of cam or weak springs or both....I just ordered a dial indicator to see what lift I have...thanks, hope I haven't sounded like a complete dumb ass.....as in the header it lays down at 6300 rpms

[ricardo1967]

Do you remember what kind of RPM it used to run before parking?

Is the exhaust system similar between the '31 Ford Tudor sedan and the '64 Chevelle dirt track car?

Have ignition and fuel (pressure) checked OK?

[Paul New]

Is it a solid lifter cam or hydraulic.  If hydraulic that about all you will get. If solid I would imagine valve springs are light or ignition issue

[captmullette]

 fuel system checked  o.k., same type exhaust, hydraulic cam.....can I help the rpms with 1.6 rockers ?  pulled the valve covers and I can turn the springs by hand on a closed valve.....not easy ign. is a procomp 6 al timing at 34 deg. didn't drive the chevelle but my driver said he remembered turning over 7000 ive heard some bad reports on procomp

[Totally T]

Better get a valve spring checker..

[Paul New]

Most hydraulic cams are only good for 6500 RPM's. Your old combo may have hit 7000 RPM's but it was on dirt and most likely spinning the tires and probably not producing any power above 6000

[captmullette]

I think you've nailed it.....1.6 rockers any help.....

[hotrod316]

we run our valves as if they where on a solid cam
set at 0 with 120 lbs closed 300 lbs open springs


 

[Paul New]

1.6 rockers probably won't change anything

[wideopen231]

agree springs first thing to check. Also 1.6 rockers will only add some lift and minor amount of duration will not do a thing for rpm issue.

[Frontenginedragsters]

Jumping in late:
 If its hydraulic then lash the valves to zero or .002" of lash.
Lifters will pump up solid and should help.
Turning springs by hand does not sound good.
We don't know what the camshaft is but I have an old Reed book.
I will check tomorrow and see if we can find a cam that fits your description.
I would NOT put 1.6 rockers on it unless you know how close your springs are to coil bind now.
Matt

[captmullette]

matt, I got a dial indicator yesterday and removed the rocker and checked the lift at the pushrod as best as I could, intake .322= .483, exh..324=.486......if you find it in your book I would really like a copy of the page etc.    thanks bobby

[Frontenginedragsters]

Bobby:
 The only Reed cams book I have is a listing of master lobes. I used to have a late 80's catalog and loaned it to someone.
You can guess that was the last time I saw that book.
The best match I can find in the listing of lobes looks like this:
.320" lift matches a lobe with 242* @.050". Didn't see one with .322" or .324"
Most oval track cams that I'v seen have a 106* lobe separation.
Good luck: Matt

[captmullette]

thanks matt, tearing the motor now changing the old iron double humps to AFR's and new cam.....looking at a lunati voodoo duration.050 is 241/249  gross lift is .525/546 flat tappet hyd. ...any thoughts ? heads are 210's

[BK]

If this is a "race motor" why hydraulic lifters?  Make sure to check piston to valve clearance.