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hunters628
10-30-2019, 20:09
Does anyone know of a set of pistons for the 6.2 that are stronger than stock? I bought a turbo setup off of a 6.5 as well as the 4911 injection pump and injectors. After I rebuild this engine I don’t wanna have to open it up again so I’d like to find something that will hold up to 12psi better than stock.
Thanks,
Hunter

Robyn
10-31-2019, 05:43
Hi.

The issue is not stronger...but lower compression.

The 6.2 has a 21.5:1 compression ratio and to pump 12 psi into it is gonna create issues.

Banks marketed a great turbo system back in the 80's/early 90's for the 6.2.

These set ups did not have a waste gated turbo and delivered about 6-7 PSI max

Unless you want to spend some serious $$$$$$ to get a set of lower compression pistons made its a tough call

The piston crowns on the 6.2 are fairly thick and the area around the outside of the swirl bowl can be machined down.....but once this is done the rotating assembly must be re-balanced to account for the material removed from the pistons.

Easy plan is to use the stock pistons and keep the boost down around 7 psi max and then be sure the fuel delivery is adjusted so you have max EXHAUST GAS temps at 1000 F at the ports at full throttle.... (NOT DOWNSTREAM OF THE TURBO)

A slight gray exhaust while pulling hard is fine.

NO COAL ROLLERS as this is just wasting fuel and building heat LOTS OF IT

A hard mashed throttle at take off will show a short puff of black smoke, but should then clear out.

If you are bent on running higher boost then a set of 18:1 pistons are the ticket.

sctrailrider
10-31-2019, 16:32
Their are ceramic thermal barriers that help reject the heat and therefor lower the amount of heat the piston retains, heat kills these motors...



I can also machine the tops and apply these coatings if you want. I'm not a vendor here just a member...


I have lots of pics on my FB page...

hunters628
10-31-2019, 18:56
Thanks for the replies. I’ve been doing more reading and since this motor will be going in a k10 SWB and the only towing it will probably ever see is a max of 3000#, would I even need to bother with better pistons (coated or lower CR)? Or would it be good measure to do so for bulletproofing. I would like to do it right the first time.
Thanks
Hunter

sctrailrider
11-01-2019, 03:33
A few things to consider, turbo pistons are still 20:1 cr but are hard anodized on the top from the factory, 6.2 pistons are not, no protection at all.



Lower cr lowers the stress on the already weak bottom end.

Robyn
11-01-2019, 05:50
A lot of the venerable old 6.2 engines were fitted with the Banks Turbo kits and ran really well.

Just don't set things on KILL and the little 6.2 will run quite nicely.

Keep the boost down under 10 PSI and the EGT AT NO MORE than 1000 F at the ports and you will be quite pleased with how the engine will perform

Make sure your injectors are in good shape (Stay away from the SO CALLED HI POPS)

The only worry about piston failure is when you start trying to make great gobs of power and boost it to the moon.



The injector thing is this.... poor worn injectors can result in hot spots and burnt pistons, as can way too much fuel and too much boost.

The 6.2 can make the same power as a good 6.5 turbo and live a long time.

Have fun

More Power
11-05-2019, 14:02
The Banks Sidewinder installation manual says that 1100 degrees F, as measured in the pre-positioned bung in their exhaust manifold should be considered maximum (I suppose for the time it takes to pull the longest steepest Interstate grade in the US - some number of minutes.)

Some years ago I spoke with a guy who drove most of a full day while towing across Texas with a Banks turbo'ed 6.2L diesel and ran the EGT at 1050 degrees the whole time. He reported no damage, even some months later.

Also... The 6.2L factory piston crowns were not coated/anodized, like the later 6.5L pistons were. This is likely why the Banks EGT max is lower than that typically allowed for the 6.5L.