IP/Injectors for 6.2 Turbo with 6.5 Heads

[adf5565]

I am in the process of obtaining parts for my 6.2 turbo upgrade. I plan on installing 6.5 heads as part of this along with a Quadstar Tuning Super 54 turbo (set for 8-10psi max). My question is, what would be the ideal injection pump (6.2 DB2 or 6.5 DB2) and injectors to match with this setup?

I know I need short (fine thread) injectors, but there are 6.2 injectors and then 6.5 injectors that fit this profile. I've already purchased the late model 6.2/6.5 injector lines for DB2 IP which should work for both setups without bending.

As my current 6.2 IP seems to work without issues, I am leaning towards purchasing the 6.2 short injectors and reusing the IP. I don't believe the 6.2 (even turbo'd) needs the additional output of the 6.5 pump and injectors.

Thoughts on this approach? Price on 6.5 injectors is comparable to the 6.2 ones. But I don't think I should have a non-matching IP and injectors.

 

[LT67]

I am in the process of obtaining parts for my 6.2 turbo upgrade. I plan on installing 6.5 heads as part of this along with a Quadstar Tuning Super 54 turbo (set for 8-10psi max). My question is, what would be the ideal injection pump (6.2 or 6.5 DB2) and injectors to match with this setup?

I know I need short (fine thread) injectors, but there are 6.2 injectors and then 6.5 injectors that fit this profile. I've already purchased the late model 6.2/6.5 injector lines for DB2 IP which should work for both setups without bending.

As my current 6.2 IP seems to work without issues, I am leaning towards purchasing the 6.2 short injectors and reusing the IP. I don't believe the 6.2 (even turbo'd) needs the additional output of the 6.5 pump and injectors.

Thoughts on this approach? Price on 6.5 injectors is comparable to the 6.2 ones. But I don't think I should have a non-matching IP and injectors.

You can use your DB2 IP. The fuel will need to be turned up... and how much I do not know.

 

[adf5565]

You can use your DB2 IP. The fuel will need to be turned up... and how much I do not know.

Thanks, yeah the current plan is to start with 1/4 turn which is based off what the old Banks kit specified. But there probably will be more adjustment needed.

 

[GopherHill]

That sounds about right. The turbo kit on my 1992 Ford used exhaust smoke density to see if you turned the pump up too much. Try for med. Gray, not black smoke at 1/4 throttle.

 

[87cr250r]

Ideally you want short+fine injectors 1988+ with lines from a 1988-1993 engine. 6.2 or 6.5 doesn't matter. I think any year 1988+ HMMWV lines will work. There are small differences between center mount and side mount/NA lines but for side mount applications I think any line will work.

The 6.2 DB2 pump has small plungers. The 6.5 turbo pump has larger plungers and is capable of more power. That's DB2-4911. With any other pump you can essentially max out the fuel screw.

 

[adf5565]

Ideally you want short+fine injectors 1988+ with lines from a 1988-1993 engine. 6.2 or 6.5 doesn't matter. I think any year 1988+ HMMWV lines will work. There are small differences between center mount and side mount/NA lines but for side mount applications I think any line will work.

The 6.2 DB2 pump has small plungers. The 6.5 turbo pump has larger plungers and is capable of more power. That's DB2-4911. With any other pump you can essentially max out the fuel screw.

Yep the lines I got are the late 6.2 or 6.5 with mechanical IP. So I should be good there.

Do you think I'll be maxing out the 6.2 DB2? As long as the 6.2 injectors (being short fine thread version) are compatible with either pump I guess I can start with my existing IP and upgrade to the 6.5 version if needed. I just don't want to purchase 6.2 injectors and then have to switch to 6.5 turbo ones if I change my IP to the 6.5 DB2-4911.

 

[87cr250r]

I am putting a turbo on my truck. I went to add 1/4 turn to the fuel screw on the pump and couldn't, it was maxed out. The truck ran at sea level with minimal smoke at max stroke. I checked another pump I had run on the engine and was only to add 1/8th. I think 1/4 over stock is essentially max. I think the engines run about 200hp with the 6.2 pump maxed.

 

[Barrman]

The DB2 4911 was the factory GM 6.5 turbo IP for about 6 weeks. Then they went to the drive by wire DB4.

If you have a 6.5 mechanical IP which has slightly bigger internals than the 6.2 IP. Then you can have a rebuild shop set it to 4911 specs.

However, I think that is overkill. I have a GEP 6.5 with a Banks 6.2 turbo and a 6.5 IP set to 4911 specs. Keeping my engine alive to me means don’t run above 10 psi boost. Boost is a function of expanding heat from the burning fuel turning the turbo turbine. The more fuel being burned the more boost can be made. I can zoom right past 10 psi if I hold the throttle to the floor. I have actually been thinking about turning my IP down a little.

Since you are going to have a mismatch set up. Get it running with what you have. see how much boost you are making and if you are getting black smoke. Black smoke is too much fuel. Maybe you’re only getting 3 psi and no smoke when on the floor at 2700 rpm. Turn the pump up. If you can get to 10 psi and no black smoke all is perfect. If you can’t then bigger IP and such comes into play.

 

[adf5565]

The DB2 4911 was the factory GM 6.5 turbo IP for about 6 weeks. Then they went to the drive by wire DB4.

If you have a 6.5 mechanical IP which has slightly bigger internals than the 6.2 IP. Then you can have a rebuild shop set it to 4911 specs.

However, I think that is overkill. I have a GEP 6.5 with a Banks 6.2 turbo and a 6.5 IP set to 4911 specs. Keeping my engine alive to me means don’t run above 10 psi boost. Boost is a function of expanding heat from the burning fuel turning the turbo turbine. The more fuel being burned the more boost can be made. I can zoom right past 10 psi if I hold the throttle to the floor. I have actually been thinking about turning my IP down a little.

Since you are going to have a mismatch set up. Get it running with what you have. see how much boost you are making and if you are getting black smoke. Black smoke is too much fuel. Maybe you’re only getting 3 psi and no smoke when on the floor at 2700 rpm. Turn the pump up. If you can get to 10 psi and no black smoke all is perfect. If you can’t then bigger IP and such comes into play.

Great info, thanks! That sounds like a good plan

 

[87cr250r]

The 3rd and 4 digits on the part number are the pump size. DB2829 and DB2831 I believe. The 6.2 engines all came with DB2829-**** pumps. The hottest 6.5 pump was the DB2831-4911

 

[LT67]

I'm looking at putting a 6.5 turbo in my 86 M1008. If I go that route I'll keep the DB4 electronic pump and relocate the PMD out from underneath the intake manifold