6.2 Performance up-grades

[AdamY]

Hi - I've got a G20 day van with a 6.2 - based in the UK. Actually a rare old van over here.

Used to use it fro towing raceboats. Van has been laid up for a while and now about to start restoring / modifying as my adventures van!

I would love to get some power out of it - open to any suggestions from mild to reasonably wild!

Must be ways of improving things???

Hope you guys can help.

Many thanks

[scottm]

Are the injectors and injector pump reasonably fresh? They have a reputation for needing to be rebuilt around 100-120k miles. I think the naturally aspirated engines have a lot more potential than they are given credit for. Heath makes a NA cam, and Stans makes headers for the 6.2. Together they should make a big improvement. Wether the cost is worth it or not is up to you, but personally I like the idea of avoiding the turbo.

http://heathdiesel.com/performance/na-66-camshaft.html

http://www.stans-headers.com/gm_headers.htm

[Dvldog8793]

Howdy
Some ideas that I have found effective for NA engines....

Open free flowing exhaust. Much can be done with the existing system by just cleaning up the manifolds and removing obstructions and then making new bigger pipes routed for better flow. Long tube headers(stan's) are great....make sure you install a cross over pipe. Depending on local ordinances you might want to install some sort of header silencer/muffler....These engines are loud when the rpms get up.

Open plenum manifold

Fresh air system with as few obstructions in the air path as possible. Do some research and air testing with your vehicle to find out where the air stream is. Some places that you think are going to positive pressure can actually be negative or neutral. Try to get the air from outside the engine bay.

A good solid fuel system optimized for the rest of the engine components.

Depending on how intense you are going....Coated pistons with different compression ratios. Internal balance and component checking.

Timing gears and good cam shaft/valve train. I have no experience with the Heath cam shaft....Would be interesting to see what it did with the whole package...not sure if just dropping a cam in would make much difference without doing some other major work.

Quality valve/head job with stud kit and new head gaskets

Make sure your cooling system is up to grade....Especially if you are running AC in hot climates

GEARING....! performance can often be a result of proper gearing for the task at hand. Different gear and transmission combinations can be VERY effective at improving FELT performance and true economy.

I try to start with the simple free stuff first...

My 1984 van has had some minor work done to it, my goal was drivability and economy. It is nice and quiet, runs great and gets about 22-24 MPG no problems passing people....but it is NOT a towing rig.

My blazer is a work in progress and will be made primarily for power and not so much economy.....we'll see

Dr Lee has some good published data on his NA engine build. look it up or better yet order the paper version. Maybe he will chime in on this post.

The main thing that I have found is that power is just a question of money and time!!!

Hope this helps!!!

[AdamY]

many thanks for the comments and much appreciated. Certainly gives me some things to think about.

looking forward to making a start - hopefully soon.

also got a bit of bodywork to do - but pretty good. Then new wheels etc.

and quite a bit on the interior......