Factory Gen 6 block with gen 5 heads?
 

Scored a 1996 gen 6 454 but disappointed to find gen 5 heads and hydraulic flat tappet cam in it. Don't see how this engine has ever been messed with as I know if came straight out of a motorhome. Had anyone else had similar experience?

Re: Factory Gen 6 block with gen 5 heads?
 

It could be one of those crossover year issues that occasionally pop up. In your case is that motorhomes have a different smog standard then a pick up, and thusly a different engine. It may have been a TBI engine with a port injection block.

So you somehow got a rare factory hybrid.

Re: Factory Gen 6 block with gen 5 heads?
 

I don't know if I feel real lucky or unlucky now. Thanks for reply you've thought the same as me. At least it's half a gen 6 I'll look for some heads down the line 👍

Re: Factory Gen 6 block with gen 5 heads?
 

I didn't know the gen 5 vs 6 heads were any different. Is there something that changed with the gen 6 to accommodate the roller lifters?

Re: Factory Gen 6 block with gen 5 heads?
 

They went from peanut ports to a smaller oval. Along with it came a revised chamber design.

The only downside to the gen6 heads are the lack of carb intakes. Supposedly they work really well for a street engine otherwise with a good cam.

Re: Factory Gen 6 block with gen 5 heads?
 

Motor homes are all about torque, they probably used peanuts for that reason. As for the flat tappet....no idea.