Great Lakes 4x4. The largest offroad forum in the Midwest banner

1970's 355 with vortec 350 head question

2K views 7 replies 5 participants last post by  ScOoTeR 
#1 ·
Hello fello Off roaders. Have a question for you.

I have a 355 in my landcruiser. Put some 70's truck heads on my engine when I built it. (76cc chambers) I know that this is bogging me down on power. Just picked up some Vortec heads off of a 1997 Tahoe. I have the stock Rockers and pushrods. I was wondering if they would work or do I need some special lengths.

How do I know for sure? Can I use my brand new z28 springs from my old Heads. I really havn't got a lot of experience with Cylinder head work.

I have some old 1964 Camel back heads that are in great shape. Was told the Vortec Heads are better. Any experiences or usable Knowledge?
 
#3 ·
If using anything other than a stock cam, you will need to have the heads machined for springs and screw in studs. If using roller rockers you will need to use guide plates. Vortec heads are great but you have to put a little effort into them if add power goodies in the motor. You will also have to use a Vortec aftermarket intake if you run a carb and you have to use the Vortec head intake gasket.

Good luck.
 
#4 · (Edited)
Nothing fancy, I just had a set cleaned up at the machine shop, Basic z28 spring and valve job, added comp retainers and Im good for .500 lift. NO extra machine work done had less than $200 into them. GREAT head for the $$$$$.

You should be able to use the springs you have just remove the inner spring. And check your install height, the vortec should be at 1.750.

The stock stamped rockers can NOT be used. A set of aftermarket 1.5 rollers will do ya. NO guide plates or screw studs needed.

I think the Push rod length is 7.2 or 7.8 going brain dead on that one.......
 
#6 ·
THanks for all the good insite. Answered a lot of my questions and confirmed my thoughts.

Not sure about the rockers and pushrods yet though. Wondered why the stock rockers wouldn't work. Seems like I would need pushrod Guides if Rollers were used.

I am going to order an aftermarket Performer Edlebrock intake unless I can find one used at a reasonable cost.

How about cam selection for Off Road Use. You guys all using low RPM camshafts like 1,000-4,500 low lift cams for your off road. I looked at the Howards cam that was a .470 straight grind and was rated for 1700-5500 and then the .435 straigh grind was 1000-4500 or something like that. I would like to keep my HP and TQ low in the RPM range for Light to Light street action and Trails. Any thoughts on that?
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top