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flash
09-12-2012, 10:38 PM
As the title says I plan to do a cam swap in my trucks 350 engine .Its on a stand in my shop and everything is off except the timing chain and the intake and distributor and the heads .I plan on putting a 290 HP stock cam in place of the hotter cam currently.It did not smoke or use oil just leaked at all gaskets due to sitting 15 years .I have a cam that was pulled from a new 290 HP crate motor not run but he seems to have shorted me the lifters .Can I buy just the lifters and use with this cam or should I buy a cam and lifters together ? I have never done this before but one of my foster boys says we can do it .All ideas and advice is welcomed .

BillsCamino
09-13-2012, 06:25 AM
You can use any brand of new SBC/BBC hyd flat tappet lifters on that GM cam. Local auto parts place will stock them.
Some basic instructions...
http://www.youtube.com/watch?v=Zr_n0cL46NM
If you get stuck on something give me a call John. Make sure you break in that new cam correctly!!!

Hank70SS
09-13-2012, 07:09 AM
Is the 290 HP crate engine a roller cam engine?

BillsCamino
09-13-2012, 07:44 AM
Is the 290 HP crate engine a roller cam engine?

Nope.

Specs per GM...
The 350/290 HP engine uses an aggressive flat tappet camshaft to achieve the level of performance for its intended usage.
Camshaft lift is .450” intake / .460” exhaust. Camshaft duration (@.050”) is 222 degrees intake and exhaust.
Lobe centerline is 114 degrees.
Normal engine manifold vacuum for the 350/290 HP engine is 10-12” Hg at idle (650-750 rpm).

BillsCamino
09-13-2012, 07:59 AM
I actually think the 350HO crate motor cam would work better for what John is trying to achieve. That engine is actually rated higher in HP but does so with slightly more compression and better heads (Vortecs).
The 350 HO 330hp cam specs...also a hyd flat tappet cam:

Cam Lift: .435” Intake / .460” exhaust
Cam Duration @ .050”: 212 deg. Intake / 222 deg. Exhaust
Lobe Separation: 112.5 Degree

Probably uses the same exhaust lobe as the 290HP cam but a milder intake profile. I plan on installing this cam in my 283 with a set of -416 305HO heads. ;)
With stock heads the engine will benefit more with a split duration cam.

flash
09-13-2012, 11:15 AM
I had planned on hiring this done but Brandon wanted me and him to do it so we will give it a spin. Thanks for all the info.

Hank70SS
09-15-2012, 06:51 AM
Nope.

Specs per GM...
The 350/290 HP engine uses an aggressive flat tappet camshaft to achieve the level of performance for its intended usage.
Camshaft lift is .450” intake / .460” exhaust. Camshaft duration (@.050”) is 222 degrees intake and exhaust.
Lobe centerline is 114 degrees.
Normal engine manifold vacuum for the 350/290 HP engine is 10-12” Hg at idle (650-750 rpm).

Okay, I just assumed all their newer crate engines were rollers.

flash
10-11-2012, 08:59 PM
I got the intake and carb off tonight and cant believe how clean everything is in there .I have got to get on the ball as the bodtshop is finally going to town on my truck. The frame is sandblasted and painted ,the cab is sandblasted and they have the rust sreas cut out and the bed is almost ready for paint .

SS Shaun
10-11-2012, 09:17 PM
Glad you posted that video because I have a question. Always put the cam in timing like that with the dots correct? So how do you degree a cam?

flash
12-10-2012, 11:29 AM
I have not had a chance to watch the video since my laptop wont let me view certain videos and this is one of them .I still have not changed out my cam as Im probably going to install a new crate motor instead but will do so later .