Great Write up. Should consider submitting to DTR Wiki for posterity...

 

Sorry for the dumb question, but what would I gain from unhooking my grid heater?

 

you must have another heater grid still hooked up somewhere to have that noticable voltage drop. my factory service manual shows 2 heater grids w/ 2 relays, so im guessing some trucks came w/ 2 of them from the factory.

if you really are still seeing a huge voltage drop when you start the truck, check around for another relay and heater somewhere.

i dont know why the factory sercice manual would show 2 of them unless some trucks come w/ them.

 

they might be talking about the fuel heater in the factory filter house and the heater grid on the intake. atleast i think there is a fuel heater there, i was told there was once but never thought to ask anyone else

 

ther is a fuel heater on in the factory filter canister.

but the service manual is showing 2 intake air heater grids w/ 2 different relays. i will look into it more later and see what i can dig up.

 

It's not a voltage drop and it's not the ECM lying to you. The ECM controls when the alternator charges and when it doesn't, and that's just what it does when you start the engine, grid heater or not.

Andy

 

Dyno tests showed about 6hp.

 

So unhooking it gets me about a 6 horse gain?

 

No, not just unhooking it, but replacing it with a gutted grid heater called a Grid Delete.

 

How do you keep your motor that clean?

 

Why do you replace the gasket under the grid heater?... If you are going to leave the grid heater in place like I am why not just replace the gasket on top of the grid heater... leaving the one under it in place... Looks like you are making more work than you have to.

Is it because you have to vac out any debris that fall in from taking off the top gasket, the one between the grid heater and the CFM horn?

 

Well, One reason is because you losened the fasteners that used to compress that gasket, and to ensure you dont have any leaks, it's a good idea to replace it.

Another is because they give you a new factory gasket in the kit. Might as well use it.

But by far, the best reason is when you loosen those 2 intake bolts closest to the valve cover, there WILL be Rust and Locktight/ sealant debris in your manifold, because they are tapped straight through to the plenum. You DO NOT want that crap going through your motor/turbo.

The top gasket that you reference didn't really require any scraping at all for me.

 

Wash it regularly with the truck and wipe it down (Dry it) afterwards.

 

"But by far, the best reason is when you loosen those 2 intake bolts closest to the valve cover, there WILL be Rust and Locktight/ sealant debris in your manifold, because they are tapped straight through to the plenum. You DO NOT want that crap going through your motor/turbo."

Thanks... That explains it .. I did not know they were tapped through, I thought they were blind.

SO what I thought was a 10 minute job is more a a 30-45 minute job.

Maybe I am over estimating what the CFM will do for me, but I think it will give me more low end, mid range, moderate to low throttle position efficiency (MPG)

I could care less about full throttle 2300 RPM HP I am after MPG and efficiency. If things flow better at 1/3 throttle while rowing the gears... and while cruising down the highway at 1750 RPM.. Then I want to install one.

If with average driving and just cruising along it does not gain anything I can't see me wasting the $300.

Can you use the factory bolts for the 2 closest to the valve covers? (to avoid scraped knuckles in the future when working there)

I am VERY close to ordering one.. CFM Owners WITH the grid heater still in place... your feedback is very helpful. What's your opinion/results

 

Wasn't there a problem with these blowing up???? Maybe I am thinking something else....