Ok, i don't see why the banks turbo would out perform the 6.5 turbo. I don't understand why it would make the motor run cooler than the 6.5 turbo. Does one turbo blow more air than the other and that is the only difference?

the banks turbo isnt waste gated plus its got some refinements in the turbine and compressor housings. the 6.5 turbo is waste gated which would help with turbo lag and ive never heard of the engine running cooler with a banks than with a 6.5 turbo. by the way what turbo are you talkin about the GM-3? or the GM-8

how are you figuring the banks is so much better? and the intake air temp can change on different turbo's depending on how effiecient they are

He figures it because 4320 said so. See below:

the banks will out preform a 6.5 turbo by far but its really expensive. the engine will last LONGER! since the EGT's while cruising are considerably lower instead of a N/A 6.2 running down the road at around 600*F EGT and a turbo 6.2 will be doin the same speed and everything and have a 400*F EGT which translates into a longer engine life since its running cooler

So, I don't exactly know where 4320 is getting his info, but it explains where Elmer got his (I think Elmer should have kept the question in that thread, but I digress).

i got that outa a banks brosure and off of other people on here

sorry if i caused problems i was just repeating what i read and heard i thought it made sence seing as a bank turbo on a 6.2 will almost even its horsepower to a 6.5

I never said you caused problems; I was just pointing to where Elmer got his info. I have no idea if you're right or wrong 4320; I'm just trying to get everyone on the same page, and there's no way I'm going to try and throw a judgment call on here as I have neither turbo setup so I'd just give misinformation.

i just dont want to be handing out mis imformation i was just saying what i read in the banks brosure i got. sorry elmer about the screw upp on my part

thats where i thought you were getting it from, Banks propaganda. a wastegated turbo should outperform a non wastegated. BUT, that will depend on how effiecient one is. eg, would be my cummins, non wastegate, takes a while to spool up, new ones with wastegate spool up way faster, but there are other variables there

oh and elmer i never said a engine with a 6.5 turbo runs hotter i said a N/A engine runs hotter since its running on less air

yea i know this is beside trucks but my tractors have non gated turbo's and they take a while to spool and when they do they work great but they suck ass untill they do

works the same

Guys, a wastegated turbo vs. a non-gated one is not gonna be one beats the other. A gated turbo can be sized smaller to achieve a lower boost threshold, but you will loose top end performance due to the turbo not producing as much airflow. You can install a larger gated turbo, but then you will be in the same boat as having just a larger non-gated one...a bigger turbo just takes longer to wake up, but will ALWAYS outperform a smaller gated one on midrange and top end. So the argument of which turbo is better really comes down to application...there isn't just one correct choice.

oh kinda the reason for compound turbo's to help get the best of a little turbo and a big turbo?

oh kinda the reason for compound turbo's to help get the best of a little turbo and a big turbo?

Basically, the larger turbo gives the high airflow for top end, while the smaller turbo gives the low threshold and compounds the boost produced by the big one. For you guys with 6.2/6.5's compounds aren't really needed or a good idea as high boost numbers aren't a good thing for those engines.

yea id go with one smaller turbo, IF I COULD FIND ONE AROUND ME!!! haha

As far as Banks vs stock 6.5 turbo......

Back in the early 90's when GM was just coming out with the turbo 6.5 there was a magazine test(sorry can't remember which one) that pitted a Banks turbo 6.2 GMC CC dually against a similar Chevy CC dually with the 6.5 turbo diesel. The banks easily won every performance test...but the 6.5 got slightly better fuel mileage. I don't remember the mileage numbers, but I do remember that they were actually very close with only a slight edge to the 6.5.

I had a Banks on my 6.2 for a couple years. Didn't like it.... EGT's high, had to run at 2500 rpm to get boost. Replaced it with a Holset turbo off a 95 Cummins. Has a wastegate which I set so even with foot floored I only get 12psi. I had to adapt the oil fittings and exhaust, but it bolts right up to the T3 manifold from the Banks. I also installed an intercooler. Now I can run at 8-10 psi at normal driving and towing speeds, and EGT's run about 800. But it doesn't spool up until you hit about 1800-2000 rpm. I'm sure there's a pressure lag from the way I installled the cooler. I puul Colorado passes now with a tool trailer, no heat issues. No difference i mileage bu that may not be accurate cause I was always babying the throttle with the BAnks before to keep EGT's down. Now I just drive.

i doubt the banks would out perform the gm-8 turbo, which came out after their comparison. there are some aftermarkets that are supposed to out perform the gm-8

I had a Banks on my 6.2 for a couple years. Didn't like it.... EGT's high, had to run at 2500 rpm to get boost. Replaced it with a Holset turbo off a 95 Cummins. Has a wastegate which I set so even with foot floored I only get 12psi. I had to adapt the oil fittings and exhaust, but it bolts right up to the T3 manifold from the Banks. I also installed an intercooler. Now I can run at 8-10 psi at normal driving and towing speeds, and EGT's run about 800. But it doesn't spool up until you hit about 1800-2000 rpm. I'm sure there's a pressure lag from the way I installled the cooler. I puul Colorado passes now with a tool trailer, no heat issues. No difference i mileage bu that may not be accurate cause I was always babying the throttle with the BAnks before to keep EGT's down. Now I just drive.

Which Holset? I am looking at Holsets for my conversion.

i doubt the banks would out perform the gm-8 turbo, which came out after their comparison. there are some aftermarkets that are supposed to out perform the gm-8


Another diesel site has tested a turbo by ***, 15-18 psi with lower IAT's without an IC and better MPG. A win, win. :cool:

Another diesel site has tested a turbo by ***, 15-18 psi with lower IAT's without an IC and better MPG. A win, win. :cool:

shhh... we used to get into trouble for mentioning that turbo... lol

shhh... we used to get into trouble for mentioning that turbo... lol

Sorry, my bad, ;)

shhh... we used to get into trouble for mentioning that turbo... lol

Sorry, my bad, ;)

ah c'mon guys.

you know your allowed tech talk about the ***.

Ive had the 6.5 turbo in a 2wd burban and the 6.2 with banks on a 4x4 burban and the banks would pull better, not a big difference but I could tell. I have since put the 6.5 turbo in my Apache so in something that light it should do pretty good.

my 6.5 runs 350F--450F doing 70 on the freeway. Its a GM3, and I have no spooling problem, but my exhaust is open which helps alot.