MPG build ?'s
#1
04-29-2018, 11:50 PM
MPG build ?'s
I'm back after a long time away (and 3 back surgeries), long story short I have been off work and sold a ton of stuff to get by including my diesel trucks...
I recently got a 85 or 86 6.2 from a M1008 that has something like 7K on it and runs good so I will be using it as is for my project for now.In the deal for this motor I also got a 93 6.5 turbo diesel with mechanical IP and thought about building it slowly then swapping them out down the rd but had couple questions. I've had good luck with the mechanical IP NA 6.2's in past and bad luck with the electric IP turbo 6.5's but no experience in middle so trying to decide what to do with the 6.5. 1st.I'm not interested in making a ton of power, just a reliable motor that gets good mpg and maybe bit more oomph than the NA6.2 (kinda what GM had in mind when making the 6.5)
So here is build I had in mind, the 6.5 is already apart due to head gasket.
Light porting on intake/heads and do valve job
Stud the mains and the heads along with a girdle on bottom end (man I wish I could afford a P400 girdle setup)
Marine "40hp" injectors-unless they actually hurt MPG, I heard they add hp and help MPG
Here is the only unusual part, I plan to supercharge the motor, I have an eaton M90 thats been ported and planned to use it along with a pulley setup that would get it to its max speed at about 3000rpm on engine. I do not plan to make over 5-8psi with this setup I just want the low end power and be able to retain the NA exhaust I am making for the 6.2. I know the ozzie's seem to like the supercharged 6.5's.
My real question is I hear all the time how to make more power with IP/timing/different pre-cups etc but what is the most fuel efficient setup of IP/timing/precups/heads. Also what about having the 6.5 sleeved to 6.2 bore for mpg/reliability or would I be better off transferring some 6.5 stuff onto the 6.2 and build the 6.2 instead? (sell the 6.5 to help fund) I like the idea of having a serpentine belt setup even if NA and the 6.5 intake looks like it would be better choice for me anyhow so I can run a sealed airbox setup not the round filter.
Truck in question will have 4spd manual behind it and headers with dual 3" exhaust is the plan.
I recently got a 85 or 86 6.2 from a M1008 that has something like 7K on it and runs good so I will be using it as is for my project for now.In the deal for this motor I also got a 93 6.5 turbo diesel with mechanical IP and thought about building it slowly then swapping them out down the rd but had couple questions. I've had good luck with the mechanical IP NA 6.2's in past and bad luck with the electric IP turbo 6.5's but no experience in middle so trying to decide what to do with the 6.5. 1st.I'm not interested in making a ton of power, just a reliable motor that gets good mpg and maybe bit more oomph than the NA6.2 (kinda what GM had in mind when making the 6.5)
So here is build I had in mind, the 6.5 is already apart due to head gasket.
Light porting on intake/heads and do valve job
Stud the mains and the heads along with a girdle on bottom end (man I wish I could afford a P400 girdle setup)
Marine "40hp" injectors-unless they actually hurt MPG, I heard they add hp and help MPG
Here is the only unusual part, I plan to supercharge the motor, I have an eaton M90 thats been ported and planned to use it along with a pulley setup that would get it to its max speed at about 3000rpm on engine. I do not plan to make over 5-8psi with this setup I just want the low end power and be able to retain the NA exhaust I am making for the 6.2. I know the ozzie's seem to like the supercharged 6.5's.
My real question is I hear all the time how to make more power with IP/timing/different pre-cups etc but what is the most fuel efficient setup of IP/timing/precups/heads. Also what about having the 6.5 sleeved to 6.2 bore for mpg/reliability or would I be better off transferring some 6.5 stuff onto the 6.2 and build the 6.2 instead? (sell the 6.5 to help fund) I like the idea of having a serpentine belt setup even if NA and the 6.5 intake looks like it would be better choice for me anyhow so I can run a sealed airbox setup not the round filter.
Truck in question will have 4spd manual behind it and headers with dual 3" exhaust is the plan.
