Jump to content

Recommended Posts

Hi guys.  I just picked up a rebuilt 1997 mark vi vortec 454 .030.  The engine was done to stock specs.  The guy I got it from started a project and abandoned it so I got the complete long block for a great price.  Everything was rebuilt/replaced on the engine.  These run about 9:1 stock compression and I'm assuming that it's going to be right around there give or take .3. 


I have a question.  I'm going to be upgrading the cam before I get further into the project.  What is the largest cam that the vortec heads can handle without machining the valve guides for seal to retainer clearance? 


I don't feel like taking the heads off and totally disassembling them.  I need a quick cam change.  I will upgrade the valve springs if necessary.  I'd also prefer to stay with the nonadjustable valvetrain vs. spending more money.  It's already going to cost an additional $1200 or so in parts for me to get this to work. 


Engine will be a carb engine with an edelbrock performer RPM intake.  Hei distributor.  Vehicle it's going in is my truck.  1992 Chevy k3500 mason dump 4x4, nv4500 5 speed with 4.56's front and rear.  Truck is heavy but I need this engine to have some power.  I don't tow, but do get loads stone (6000lbs on average) and the 350 that was in it required downshifts on hills even unloaded.  I'd like this to pull above 5k and not die out like the TBI 350 did at 3800.  Truck weighs 7540 with me in it.


Any advice?  Thanks. 

Link to post
Share on other sites

That's why I put this in the misc. tech section. Comp doesn't say this is max lift with a certain engine. They won't for fear of a mistake.


However, I thought maybe someone here had a prior experience with this engine where I could get an answer. It's a bbc which people do have in their Datsun and it's a general engine question si it's relevant. No different than saying how much cam lift can a stock 5.0 engine out of a mustang handle?

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...