New 1008 owner Turbo 6.2 or Yurbo 6.5

[RIDEBANSHEE]

Alright everyone, I am new to this Forum. I was a 63S in the Army so I'm not new to these at all. However I finally picked one up. I know they don't have much power and was looking at upgrading. I have a NV4500 setup for it and the truck i got it out of had a turbo 6.5. My question is would I be better off putting the whole 6.5 in the truck or taking the turbo setup off and putting it on he 6.2. Truck will mainly be used for wheeling and occasional pulling a small trailer. I have read alot of the articles but looking for opinions for my goals. Thank you

 

[chevyCUCV]

Search, people have asked this question for 20 years now

I dont think there are any proof that any 6.2 or 6.5 is better than the other, they all have problems.

I would start by pulling oil pans to verify no cracks in the block/mains. that is #1

 

[Iceman3005]

If it were me and the 6.5 is all mechanical (early 90's 6.5) I would just swap whole motor and trans. much easier than trying to mate the nv4500 to the 6.2, and trying to fit the turbo on the 6.2 is a pain from what I hear. If the 6.5 has A/C then there is another bonus, plus I think there is some brackets out there if you want to keep the 2nd Alt. for the 24 volt.

 

[wayne pick]

I would go with the 6.5 as it was designed to have a turbo. It would be risky to turbo the 6.2 without lowering the compression ratio, installing stronger head studs and a crank girdle. Thicker head gaskets can be used to lower compression. There is no proof of the crank girdle actually making a difference, but it can't hurt. Swapping the turbo parts to the 6.2 can be done, but why bother. I don't see any problem mating the nv4500 to the 6.2. The 6.2 and 6.5 blocks are identical as is the Chevy engine to trans bolt pattern going back to the early 1960s. I have a Banks setup on my truck, I try not to hammer on it to much.

 

[patracy]

I would go with the 6.5 as it was designed to have a turbo. It would be risky to turbo the 6.2 without lowering the compression ratio, installing stronger head studs and a crank girdle. Thicker head gaskets can be used to lower compression. There is no proof of the crank girdle actually making a difference, but it can't hurt. Swapping the turbo parts to the 6.2 can be done, but why bother. I don't see any problem mating the nv4500 to the 6.2. The 6.2 and 6.5 blocks are identical as is the Chevy engine to trans bolt pattern going back to the early 1960s. I have a Banks setup on my truck, I try not to hammer on it to much.

So the retrofit kit that was a dealer option from Banks on the 6.2 from GM was a bad idea? Or the fact that they used the Banks system to base their turbo system design?

The 6.2 had a 21.5:1 CR. The early 6.5 had a 21.3:1 CR, late 20.3:1.

You can blow a 6.5 just as easy as a 6.2 when it comes to boost. Especially with the GM-X series of turbos. The factory turbos were designed only for bottom end and fast spooling. That translates to high boost pressure from mid to high range. The 6.2 and 6.5 both have block issues, now I will say that adding a girdle is only a good idea. But the turbo thing, well that's just a matter of keeping it under 12psi when using any GM-X model turbo.

 

[wayne pick]

So the retrofit kit that was a dealer option from Banks on the 6.2 from GM was a bad idea? Or the fact that they used the Banks system to base their turbo system design? I never said it was a "bad idea", I said it is risky. The dealer installed turbos were on new engines, not engines that have unknown history or mileage. Just slapping a turbo on a 6.2 without removing and inspecting the heads and replacing the head gaskets and studs is indeed risky. Inspecting the lower end for web cracks is also a good idea. Not looking for an arguement, just stating an opinion.