over the winter i installed the MTC-5 cam, ported the heads (basically smoothed out any rough edges thats all) removed EGR and heater and thats about it. i cant see that i would lose over 6MPG (from high 25s to low 19s) from this lil upgrade. EGR should hardly affect it and deleting the heat shouldnt affect it at all. any thoughts on this? im wondering if the timing chain being a tooth off could affect it at all, but i dont think it would be like that. i think it would be more drastic.

 

if the timing chain wa soff one tooth u would know it,car would prolyl barley run.and i dont see an egr delete hurtuing u that bad.when i got rid of mine i had no milage loss.id look into something along the lines of bad injector,or another sensor being bad

though depending on how much flow u picked up when u ported the heads,that could be ur whole reason right there.u didnt make the intake ports very smooth did u?

 

for porting, basically all i did was remove any sharp edges in the heads and the lower intake manifold i just opened that up and matched it to the intake ports on the heads. i didnt polish them but theyre definetly better than before. im not a performance pro but i have taken machining classes and cant see how what i did affect it that much.

 

well i was gonna say if u polished them completly smooth that actually hurts perfomance/gas milage.if ur heads are flowing that much better then they did stock u could see a good loss in gas milage but not the kind u are seeing,but id be willing to be on 2-3 mpg,depending on how well u did the heads

 

I still have a vac leak with my mtc-5. My mpg is sucking *** right now too.

I belive I have some valves sticking open as I dont have the power that the orginal mtc5 had. Maybe you do as well?

 

well, as well as an MPG loss, when my car sits overnight, i also notice a lifter tick at first start up for about 2-5 seconds. the tick leads me to believe that the rockers are out of adjustment, but the MPG.... i dont know, aside from the extended time of startup. maybe a leaking injector, which i had before when i had the 2.8.

 

You'd be suprised how much an EGR delete will affect your MPG. Are you getting a code for it?

When you introduce EGR into the intake, the amount of fresh air is reduced and therefore not metered for fuel, now that you are sucking more air through the MAF, it's metering in more fuel. Also, unless you programmed it out, the ECM adds timing when the EGR is engaged, so that helps your milage too, if it sets an EGR code and stops using it, it doesn't advance the timing either.

 

i knew it would go through more fuel, i just didnt think it would be that much. that makes me consider putting it back on.

 

I put mine back on simply because of the SES light. It runs cooler, and gets better mpg with it on .

Think I fixed my vac leak yesterday

 

Yeah, removing ionly makes the engine bay look better and eases access to #3 and #5 plugs, there are zero perfornmance gains to be had with removing it. It's just that they tend to make EGR systems so intrusive and ugly that it's kinda nice to ditch them.

 

I wouldn't remove the EGR either. I did notice it was a tad better on flat out runs but the idle was to funky stopped. But the tiny bit of difference wasn't worth it.

Id run some seafoam in your oil if you think things are sticking. It save thousands in the Subaru world. The infamous tick of death is often fixed wit ha bit of Seafoam. It is also big in the bike world for fixing strange carb problems. One of them snake oils that really works.

 

Your EGR Valve itself must have been sticking open then because on a flat out run, you should have 0 vacuum, so the EGR would be completly unable to open anyway, even if it was commanded on.

 

i only ditche dmine cause of the whole turbo system.the valve is stillthere but it hass blockoff plates on both sides.was fariad the presure in the ex system would force the valve open under boost,cause there is always the possibility of my backpresur ein the ex system then u make in boost at the manifold