Author Topic: stock cam  (Read 3332 times)

0 Members and 1 Guest are viewing this topic.

Grbmaverickmo

  • Jr. Member
  • **
  • Posts: 93
    • View Profile
stock cam
« on: July 12, 2014, 08:26:22 PM »
Whats the fastest anybody has been with a stock .410 lift 390 cam????? I was at Beaver today talkin to a fella who told me that if I changed valve springs my stock cam would turn 6000 instead of the 3900 that it does now. So before I put a set of heavy springs on it and hurt something has anybody else ever  done this?? Thanks

jayb

  • Administrator
  • Hero Member
  • *****
  • Posts: 7406
    • View Profile
    • FE Power
Re: stock cam
« Reply #1 on: July 12, 2014, 09:06:04 PM »
Are you sure that its the valve springs that are holding you back?  Another likely culprit is the points; rarely do the stock distributor/points setups go past 5000 RPM before limiting engine speed.  If you are running a stock distributor (meaning points, not electronic), you might want to invest in a set of high tension points.

If it is indeed the valvesprings, a good set will allow the engine to rev to 6000 RPM.  The cam is capable, although you will probably hit your power peak around 5000 RPM, so going all the way to 6000 may not buy you anything.
Jay Brown
- 1969 Mach 1, Drag Week 2005 Winner NA/BB, 511" FE (10.60s @ 129); Drag Week 2007 Runner-Up PA/BB, 490" Supercharged FE (9.35 @ 151)
- 1964 Ford Galaxie, Drag Week 2009 Winner Modified NA (9.50s @ 143), 585" SOHC
- 1969 Shelby Clone, Drag Week 2015 Winner Modified NA (Average 8.98 @ 149), 585" SOHC

   

cjshaker

  • Hero Member
  • *****
  • Posts: 4460
    • View Profile
Re: stock cam
« Reply #2 on: July 12, 2014, 10:11:10 PM »
My F250 with a solid cammed 390, stock re-manufactured distributor and points, has had no problem running to 5500 for 20 years now. The points trigger a MSD Blaster ignition (not available now), but I never encountered points "bounce" once. I believe wore out upper bushings cause most points problems up to that point, and I have seen that on many occasions. I did BUST a set once. Only time that ever happened.

But like Jay said, anything past 5000rpm max is just a waste with a stock cam. Not sure why anybody would want to do that unless it was just to prove a point. And that point could cost you an engine if the shaft system isn't built to handle those rpms.
Doug Smith


'69 R-code Mach 1, 427 MR, 2x4, Jerico, 4.30 Locker
'70 F-350 390
'55 Ford Customline 2dr
'37 Ford Coupe

Grbmaverickmo

  • Jr. Member
  • **
  • Posts: 93
    • View Profile
Re: stock cam
« Reply #3 on: July 13, 2014, 08:51:16 AM »
My seat pressure is at 80lbs and I have the Accel points set which is suppose to be heavier. It will spin to 5 or a little higher but it slows down ET wise. The car goes the quickest shifting at 3900 so far. I was thinking about redegreeing it and retarding it 4 degrees. I did that with a 5.0L that I had with a stock roller cam and it helped a lot. It took some wheel spin away and pulled to 6000. I got that car to 12.80`s with good tires and it went 108 mph. I know that its a whole diff motor and car weighs more. Mustang was 3000 with me and 54 is 3600. I just think I can get this into the 13`s maybe 12`s and still drive it regularly

rcodecj

  • Sr. Member
  • ****
  • Posts: 474
    • View Profile
Re: stock cam
« Reply #4 on: July 15, 2014, 10:29:24 AM »
My seat pressure is at 80lbs and I have the Accel points set which is suppose to be heavier. It will spin to 5 or a little higher but it slows down ET wise. The car goes the quickest shifting at 3900 so far. I was thinking about redegreeing it and retarding it 4 degrees. I did that with a 5.0L that I had with a stock roller cam and it helped a lot. It took some wheel spin away and pulled to 6000. I got that car to 12.80`s with good tires and it went 108 mph. I know that its a whole diff motor and car weighs more. Mustang was 3000 with me and 54 is 3600. I just think I can get this into the 13`s maybe 12`s and still drive it regularly

What is the ET now?