Chevy High Performance
Click here to find out more!

GEN1 350 Valve train specs?

  
Chevy High Performance
Item Posts    Sort Order

GEN1 350 Valve train specs?

 
hansw3 hansw3
New User | Posts: 6 | Joined: 09/07
Posted: 04/28/10
08:08 PM

Anybody know where there are specs on valves and valve seats for small block chevy 350 Gen1?

I have my heads apart and I'd like to measure the parts up and decide if I need to rebuild them. Boring it out .060 currently and getting the summit rebuild kit with new pistons, bearings, gaskets, etc...  The guides have a little wear in them too.  I'm thinking recutting the seats, grinding the valves and knurling the guides then reaming may be in order but I'm not sure thaqt it's in that bad of shape.  

ALso interestied in things like installed spring height, etc. Surely for all the millions of these motors out there there's got to be some good published sources avaialable for free on the internet. I guess I don't know the right key words or something because I'm not finding it.  

skyeking skyeking
Addict | Posts: 2738 | Joined: 08/09
Posted: 04/28/10
10:04 PM

Hi there,
 For 20 years GM/Chev used the one cam in MANY cars with 305 and 350 motors and
 used the cam {one of which I had in HP 210hp///305.. It was called the 'Lazy"
 Cam ..Specs were basically speaking 214*/224* @ 50/1000" and lift is approx
 .420"inlet and .442"Ex..Hyd Flat tappett..was copied by Comp cams?? and is still
 listed with GMPP..This cam went into low power Corvettes and just about all else
 On my 355 motor with 600 Holley//headers etc and 10/1 comp put out about 310lbs
 torque and at best 275 bhp under 5000 rpm with performer mainifold with 1" spacer.
   Hope this helps with Dyno readings that cost $$$$...Skyeking.....
 You can get all the factory cam dope in GMPP books in the last 7 editions.....  
skyeking

hansw3 hansw3
New User | Posts: 6 | Joined: 09/07
Posted: 04/29/10
04:08 AM

That's interesting info.  I should have been more clear perhaps though...  I'm simply looking to compare the state of my valves (Seat width, angles, edges, etc) to a spec on what is allowable.  I don't want to drop the cash on recutting seats, grinding valves and reworking the guides if I don't need to.  

ethelkilledfred-#001 ethelkilledfred-#001
Guru | Posts: 1371 | Joined: 03/10
Posted: 04/29/10
04:35 AM

Icon Quotehansw3:
Anybody know where there are specs on valves and valve seats for small block chevy 350 Gen1?

I have my heads apart and I'd like to measure the parts up and decide if I need to rebuild them. Boring it out .060 currently and getting the summit rebuild kit with new pistons, bearings, gaskets, etc...  The guides have a little wear in them too.  I'm thinking recutting the seats, grinding the valves and knurling the guides then reaming may be in order but I'm not sure thaqt it's in that bad of shape.  

ALso interestied in things like installed spring height, etc. Surely for all the millions of these motors out there there's got to be some good published sources avaialable for free on the internet. I guess I don't know the right key words or something because I'm not finding it.


Performance Head Build - Some Assembly Required
Direct link- http://www.chevyhiperformance.com/tech/engines_drivetrain/cams_heads_valvetrain/0612ch_head_build/head_specs.html  
-

Brotherhood of Street Racers

My Space Brotherhood of Street Racers
http://www.myspace.com/brotherhoodofstreetracers

BSR-International
http://bsr-international.ning.com/

ethelkilledfred-#001ethelkilledfred-#001

hansw3 hansw3
New User | Posts: 6 | Joined: 09/07
Posted: 04/29/10
03:39 PM

The first link worked but not the second two.

thanks  

tuffnuff tuffnuff
Moderator | Posts: 7827 | Joined: 12/09
Posted: 04/29/10
08:25 PM

Icon Quotehansw3:
The first link worked but not the second two.

thanks


EKF only gave you one link for the specs,,, that should get you started,
the other two are his Street Racer Associations.
Smile  
When The Flag Drops.,.

tuffnuff

The Bull ***t Stops.,.
tuffnuff

P. Engineer, Engine Builder

hansw3 hansw3
New User | Posts: 6 | Joined: 09/07
Posted: 05/01/10
12:22 PM

My shop is hot tanking and then magnafluxing the heads.  For $5 per valve seat they will cut the triple angle.  He said my seats and valves actually looked okay but I'm going to have him cut the seats anyway. I am going to attempt to grind the valves at home on my Boyer Shultz surface grinder  and a 5C indexing spin fixture and an 11/32 collet.

Also decking .025 from the block.  The shop estimated I have 8.3:1 static compression without decking with my 76cc smog heads (1.94/1.5 valves).  He guessed another .5 increase in my comprssion.  When I figure where I'm at w/o decking I get 8.5:1 and 9:1 w/decking.  REgardless I'll be at 8.8:1 minimum.  They claim they've done this many times with piston to valve clearance issue.  Hopefully they're right!  They are adding $100 for decking the block.  

The valve springs measured 50 lb at 1.700" height and according to shop they should be 70lbs.  I will replace the springs with new OEM ones because I am keeping the OEM camshaft.

The only thing I'm on the fence about is the valve guides.  THe shop said the valves don't feel too bad installed in the guides for side play.  I have mic'd out the stems to be around .341" diameter.  They want $10/valve to drill out my old guides and install new cast iron ones.  They don't recommend the bronze ones.  Either this will be a job on my bridport at home or I won't replace the guides at all.

Just thought I'd share a little more on my first beginning to end rebuild on my own dime of my own motor...