6.2... no compression #7

[turbovanman]

This thread got me to thinking more about what might be w/ mpg since adding my turbo. So running the comparison test best I can.

When driving non turbo I had 10.4 mpg. Always wot from stop until speed limit.
I added gm6 center mount turbo, swapped my injectors for turbo injectors that had within 10,000 miles of wear of my n/a injectors. turned up fuel screw 1 turn. homemade turbo master. 9 psi boost max, and on hiway at 78 mph 3000 rpm I have 3psi boost. I still have not increased the exhaust size. The only other change that is a variable is the intake manifold was a normal truck lower half and is now the van 3 piece set up. Definitely not as good a flowing manifold.

Again full throttle from every stop, truck is much quicker and will leave a puff of smoke at take off, so a little unburned fuel happening but not a tremendous amount. I used to be passed by EVERY CAR leaving stoplights. Now I am in front unless someone is pushing their ride. I "drag raced a buddy with a prius, he used to leave me way behind. Now I take him up to 40 mph. MPG driving like this? 10.4 mpg- exactly the same.

So for the last 2 tanks(on #3 now) I am on the throttle about 75%-80% from the stoplight. It's as close to the old acceleration rate as I can estimate. I still drive at the same top speeds as normal. I have (out of habit) went wot a couple of times a day almost every day, so still not perfect, but closer. So far tank #1 was 11.8 mpg, tank #2 was 11.9 mpg. That's not a lot of money, but a descent percentage gain.

Is there other people who added a turbo and showed a note-able drop in mpg? I can't image worse high rpm restriction being at 3,000, still on 3 psi boost. My weight is roughly 7,000 lbs currently, so getting those 37" 148# ea tires a rollin has to be worse than most.

My van weighs 6000 lbs, brick front end. N/A I got 18 mpg city/hwy with small hills, towing, I got 11/12. My parents have a house where you have to drive up stupid hills/mountains. I hated going there as you had to drive it like a 2 stroke and go stupid fast down hills so you could up the hill's, 11 mpg. After turbo, city/hwy stayed the same, but towing went up to 16 and my parents house, the trip also went to 16 mpg, and now, I could relax driving, no more frazzled nerves, if someone blocked me, and the A/C is cranked. Now running waste fuels and she dropped to 15mpg in any driving mode.

I guess the GMx turbo is the reason for the MPG dropping so in that case, put a real turbo on. :hihi: