Re: Comp suggesting a way light spring??
[Re: Moparnut426]
#874758
12/08/10 05:35 PM
12/08/10 05:35 PM
|
Joined: Feb 2003
Posts: 4,953 Houston, Texas
TheOtherDodge
master
|
master
Joined: Feb 2003
Posts: 4,953
Houston, Texas
|
I run into this a lot. The cam mfg says a spring that is way to light according to my engine builder. So there is a tough quandry because you generally like to follow the mfg recomendations... I always do what the engine builder suggests, which is more spring pressure and have never had a motor fail because of that. Once again, generally, you won't have a problem if there is too much spring pressure (to a point) vs. too little...
|
|
|
Re: Comp suggesting a way light spring??
[Re: TheOtherDodge]
#874759
12/08/10 05:37 PM
12/08/10 05:37 PM
|
Joined: Feb 2003
Posts: 4,953 Houston, Texas
TheOtherDodge
master
|
master
Joined: Feb 2003
Posts: 4,953
Houston, Texas
|
This also reminds me about a discussion with Holley carbs years ago... There was some discussion that one of thier carbs (don't remember which one but use the 950 as example) and that it didn't really flow 950 but rather 890. I asked Holley about that and they said if it flowed 890 they would have called it an 890....
|
|
|
Re: Comp suggesting a way light spring??
[Re: TheOtherDodge]
#874761
12/08/10 05:41 PM
12/08/10 05:41 PM
|
Joined: Mar 2007
Posts: 12,008 Finally a HUSKER again
Moparnut426
OP
I Live Here
|
OP
I Live Here
Joined: Mar 2007
Posts: 12,008
Finally a HUSKER again
|
Quote:
I run into this a lot. The cam mfg says a spring that is way to light according to my engine builder. So there is a tough quandry because you generally like to follow the mfg recomendations...
I always do what the engine builder suggests, which is more spring pressure and have never had a motor fail because of that.
Once again, generally, you won't have a problem if there is too much spring pressure (to a point) vs. too little...
Exactly what these builders said. Hardly ever see a stem pulled away from a valve.
Kasey
|
|
|
Re: Comp suggesting a way light spring??
[Re: Moparnut426]
#874762
12/08/10 07:16 PM
12/08/10 07:16 PM
|
Joined: Jun 2003
Posts: 52,972 Romeo MI
MR_P_BODY
Master
|
Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
|
I run 320# on seat and alot more than that on the top, still running the same springs and lifters now for a few years and I check them yearly but its only .710 lift (PAC springs)
|
|
|
Re: Comp suggesting a way light spring??
[Re: MR_P_BODY]
#874763
12/08/10 07:20 PM
12/08/10 07:20 PM
|
Joined: Mar 2007
Posts: 12,008 Finally a HUSKER again
Moparnut426
OP
I Live Here
|
OP
I Live Here
Joined: Mar 2007
Posts: 12,008
Finally a HUSKER again
|
Mr P, The cam is only 575 lift, and its a street cam, so my "over the top" springs shouldnt hurt a darn thing. I could be wrong though.
|
|
|
Re: Comp suggesting a way light spring??
[Re: MR_P_BODY]
#874764
12/08/10 07:23 PM
12/08/10 07:23 PM
|
Joined: Jan 2003
Posts: 4,616 Kissimmee Fl.
dusturbd340W5
master
|
master
Joined: Jan 2003
Posts: 4,616
Kissimmee Fl.
|
with a solid roller it is better to have more than you need than not enough I am running 340 at 1.900 and am over 700 at just before coil bind.
70 duster full chassis super pro 416 CNC Indybrock heads 727 w/brake
best so far 1.212 60 6.219 in 1/8 at 110.88 9.768 at 137.81 1/4
|
|
|
Re: Comp suggesting a way light spring??
[Re: Moparnut426]
#874768
12/10/10 12:58 AM
12/10/10 12:58 AM
|
Joined: Aug 2003
Posts: 43,190 Bend,OR USA
Cab_Burge
I Win
|
I Win
Joined: Aug 2003
Posts: 43,190
Bend,OR USA
|
I've found that the more spring pressure I run on my Duster motor the better the cam looks I started with 225 to 230 lbs on the seat and 620 to 630 lbs opened, now up to 275 on the seats and 680 open That set up is very stable to 8400 , according to the playback tach when I broke a front U joint and trans yoke during a run
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
|
|
|
Re: Comp suggesting a way light spring??
[Re: Cab_Burge]
#874769
12/10/10 01:28 AM
12/10/10 01:28 AM
|
Joined: Jul 2010
Posts: 2,091 Delray beach, Florida
Performance Only
top fuel
|
top fuel
Joined: Jul 2010
Posts: 2,091
Delray beach, Florida
|
the spring pressures that comp recommends for their street roller cams will work, but i prefer a bit more assurance that the roller will stay seated on the cam. just don't go overboard. the pressures you have now will work just fine.
machine shop owner and engine builder
|
|
|
Re: Comp suggesting a way light spring??
[Re: Evil Spirit]
#874771
12/10/10 07:01 AM
12/10/10 07:01 AM
|
Joined: Jan 2003
Posts: 10,000 Frostbitefalls MN (Rocky&Bullw...
gregsdart
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 10,000
Frostbitefalls MN (Rocky&Bullw...
|
I gained about 40 hp and quit breaking parts going much heavier than recommended. It could have been the design of the spring, or just too light of a spring . Your results may vary .
Last edited by gregsdart; 12/10/10 07:03 AM.
8..603 156 mph best, 2905 lbs 549, indy 572-13, alky
|
|
|
|
|