Go Back   EcoModder Forum > Introductions
Register Now
 Register Now

Reply  Post New Thread
Submit Tools LinkBack Thread Tools
Old 06-13-2011, 02:49 AM   #11 (permalink)
Frank Lee's Avatar
Join Date: Jan 2008
Location: up north
Posts: 12,762

Blue - '93 Ford Tempo
Last 3: 27.29 mpg (US)

F150 - '94 Ford F150 XLT 4x4
90 day: 18.5 mpg (US)

Sport Coupe - '92 Ford Tempo GL
Last 3: 69.62 mpg (US)

ShWing! - '82 honda gold wing Interstate
90 day: 33.65 mpg (US)

Moon Unit - '98 Mercury Sable LX Wagon
90 day: 21.24 mpg (US)
Thanks: 1,585
Thanked 3,553 Times in 2,217 Posts
Ha- like a five foot shorter one is going to make a difference.


  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

Old 06-13-2011, 09:44 AM   #12 (permalink)
Even a caveman can do it!
b1jetmech's Avatar
Join Date: Mar 2010
Location: Michigan
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
Originally Posted by Frank Lee View Post
Ha- like a five foot shorter one is going to make a difference.
Yeah...it made the conversion a whole lot easier!

96-99 though the same on the outside have minor differences like brackets, accessory locations, shifting cable connection, trans mission cooling lines, ect.

It all added up.
99' Suburban K1500
6.5 diesel non turbo/4l80e conversion
Out with the gas 350!
  Reply With Quote
Old 06-13-2011, 02:30 PM   #13 (permalink)
home of the odd vehicles
rmay635703's Avatar
Join Date: Jun 2008
Location: Somewhere in WI
Posts: 3,789

Silver - '10 Chevy Cobalt XFE
Thanks: 469
Thanked 833 Times in 629 Posts
Originally Posted by b1jetmech View Post
Hey thanks for the response!

After a few months of driving with the converted diesel I'm averaging 20 MPG. That's up from 11 which isn't bad I must say.
If that helps but the mileage doesn't improve much then the injector pump will be looked at.

Then engine runs great. There is NO blow by which is unheard of with these but being a non turbo motor...it didn't have to suffer the abuse of turbo because GM kept these engine's compression ratio very high. Just like Ryan said, Too much compression plus boost = BOOM!

I do have a turbo set up but won't be installing it anytime soon. I'm having the urge to convert back to gas. Want to try a 305 tune port from the late 80's early 90's because they got good mileage and having tune port gave it a real good low end torque but we'll see!

Another item on the to-do list is turn the fuel up. I have a hard time accelerating up to highway speeds because the motor runs out of steam about 55 mph. The fuel curve is way below because this engine doesn't belch smoke. I have never seen black smoke under any load. so an 8th of turn on the IP should wake it up a little.

over all I do like it but have the tune port ideal in the back of my mind we will see on that one.

Ryan, If I pull the heads for anything I just might install some 6.2 pre cups. I have heard of 6.2 Burbs getting in the mid to upper 20's in MPG.
Generally 6.5s never quite match what the lowly early C code 6.2s would achieve, its not tuned for economy as much as it is for safety/reliability.

The precups you would want for improved economy would be similar to a C code 82ish motor.

Naturally aspirated diesels are NOT earth moving rigs, they rumble slowly up to their speed. The best way of improving performance is to have more gears and get the motor in a better RPM band while accelerating.

That said our 93 GAS suburban 2wd would get 20mpg on the highway when running correctly (same as your 6.5) Of coarse only 93 year 2wd 350s got that, a couple years later and they had trouble with 18mpg

So in other words you 6.5 should be able to do better than a 350 gasser, you would just need it geared right with a good selection of gears and tuned right, generally you want it a little on the advanced side and a little rough to get the best FE, otherwise you are just blowing it out the tailpipe.

Also injectors and pump have a massive FE effect if they aren't working as they should, before turning the thing up fix the injectors and if need be pump before you do it, turning up a bad pump can make it badder faster (and not in the good way)

Last edited by rmay635703; 06-13-2011 at 08:32 PM..
  Reply With Quote
Reply  Post New Thread

Thread Tools

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2023, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com