cam selection

General Engine Discussion

Moderator: John_Heard

Post Reply
Message
Author
jacobgiles
Posts: 100
Joined: Fri Jul 01, 2005 10:32 am
Location: millington, tn

cam selection

#1 Post by jacobgiles » Fri Jul 15, 2005 7:34 am

im building a streetable 406 for my nova.it is .030 over, compression is around 9.5-10, 5.7 rods, it has dart iron eagles that are 215cc, 1.60 2.08,64cc i have a holley 750 and victor jr intake and a nos plate. im trying to decide on a cam. im leaning towards a comp XR286R. it is 248 254 @ .050" and .576 .582 lift and 110 LSA. is this a good selection for my motor? i primarily drag race the car but i like to drive it to the track sometimes and do the cruise-in thing too.

jacobgiles
Posts: 100
Joined: Fri Jul 01, 2005 10:32 am
Location: millington, tn

#2 Post by jacobgiles » Fri Jul 15, 2005 7:38 am

i forgot to mention that its a solid roller

User avatar
John_Heard
Site Admin
Posts: 5734
Joined: Thu May 12, 2005 11:20 am
Location: Resume Speed, Kansas
Contact:

#3 Post by John_Heard » Fri Jul 15, 2005 10:07 am

That sounds about right, maybe one of the other guys will have some suggustions. I'm a bit out of touch on the small block stuff, but that sounds pretty close to the Lunati solid lifter cam Roger (MOKANRACER) on this board used in his 383. Worked pretty good on his but he used a lot more compression.

Oh yeah, welcome to the forums...

John

User avatar
jones_performance
Posts: 184
Joined: Thu Jun 30, 2005 3:38 pm
Location: upland, ca

#4 Post by jones_performance » Fri Jul 15, 2005 7:12 pm

that cam will work alright,

myself id go with say around .620 lift and around 255 at .50 duration on a 106 lobe center if i was doing more drag racing than street driving.

what piston are your running? with say a flat top srp piston with the 64 chambers you should be close to 10.5 or higher depending on the number of valve reliefs.
Kevin

User avatar
MOKANRACER
Posts: 277
Joined: Thu May 12, 2005 1:40 pm
Location: S.E.Kansas
Contact:

Re: cam selection

#5 Post by MOKANRACER » Fri Jul 15, 2005 8:28 pm

jacobgiles wrote:im building a streetable 406 for my nova.it is .030 over, compression is around 9.5-10, 5.7 rods, it has dart iron eagles that are 215cc, 1.60 2.08,64cc i have a holley 750 and victor jr intake and a nos plate. im trying to decide on a cam. im leaning towards a comp XR286R. it is 248 254 @ .050" and .576 .582 lift and 110 LSA. is this a good selection for my motor? i primarily drag race the car but i like to drive it to the track sometimes and do the cruise-in thing too.
Yeah,that will be a fun ride for sure. My new mtr just built has a Lunati flat tappet 40119.with my 1.6:1 rockers gives me ,580 and .601 106 seperation. But I,m running 14.5:1 compression. Your roller will work really good for you. I just couldnt spring for the roller this time around.I,m riunning the 215 Darts with the 49cc chambers. So am limited on lift. Hoping to tune to 10,s....? Roger

Guest

#6 Post by Guest » Sat Jul 16, 2005 3:20 pm

ok, i dont know how true this is but, i have been told by some of the techs at comp cams that you really arent gonna gain a whole lot on the spray with a 106 or 108 LSA they have said that the nitrous is more efficient with a 110 or a 112. honestly i dont really know the differance betwwen a 106 or 110 LSA. will having a higher lobe seperation hurt power when off the gas? somebody please explain.-thanks,jacob

jacobgiles
Posts: 100
Joined: Fri Jul 01, 2005 10:32 am
Location: millington, tn

#7 Post by jacobgiles » Sat Jul 16, 2005 3:27 pm

kevin, wouldnt that cam be pushing it a little too much for street driving? how would it work with 10.5 compression? how would it work with a 10"tci streetfighter converter? i only have 3.50 gearsas well. and somebody explain the whole LSA thing to me!

User avatar
MOKANRACER
Posts: 277
Joined: Thu May 12, 2005 1:40 pm
Location: S.E.Kansas
Contact:

Spray vs LSA..

#8 Post by MOKANRACER » Sat Jul 16, 2005 3:30 pm

Anonymous wrote:ok, i dont know how true this is but, i have been told by some of the techs at comp cams that you really arent gonna gain a whole lot on the spray with a 106 or 108 LSA they have said that the nitrous is more efficient with a 110 or a 112. honestly i dont really know the differance betwwen a 106 or 110 LSA. will having a higher lobe seperation hurt power when off the gas? somebody please explain.-thanks,jacob
Havent heard that one before. Lower number suppose to give ya more power. I,m only going to spray 100 to 150 as Ive got lots of cranking pressure now. Would be interesting to see what kind of answers you get back. I spent a week talking to Lunati,as they speced my other cam out,and I had 250 PSI cranking pressure. They said if I went to 110 it would bleed a lot off, but but would lose Horse Power, I,m going to be running mostly mtr only any way.

User avatar
jones_performance
Posts: 184
Joined: Thu Jun 30, 2005 3:38 pm
Location: upland, ca

#9 Post by jones_performance » Sat Jul 16, 2005 7:16 pm

jacobgiles wrote:kevin, wouldnt that cam be pushing it a little too much for street driving? how would it work with 10.5 compression? how would it work with a 10"tci streetfighter converter? i only have 3.50 gearsas well. and somebody explain the whole LSA thing to me!
thats why i said if you are drag racing more than street driving ;)

some info on lsa

What is Camshaft Lobe Separation and how does it affect the engine?

Lobe separation is the distance (in camshaft degrees) that the intake and exhaust lobe centerlines (for a given cylinder) are spread apart. Lobe separation is a physical characteristic of the camshaft and cannot be changed without regrinding the lobes.

This separation determines where peak torque will occur within the engine's power range. Tight lobe separations (such as 106°) cause the peak torque to build early in basic RPM range of the cam. The torque will be concentrated, build quickly and peak out. Broader lobe separations (such as 112°) allow the torque to be spread over a broader portion of the basic RPM range and shows better power through the upper RPM.
Kevin

Post Reply

Who is online

Users browsing this forum: Google [Bot] and 24 guests