My turn! My BB Tune is HERE!

It's here! It took two weeks to get here, but it's here! It showed up this morning!

I had no idea that a computer from a 98 Jimmy would work in our Yukon's and Tahoes after flashing, but I guess it makes sence!






I can't wait for it to be installed!
Tomorrow morning, I get my tune installed, my underdrive pulleys installed, and my efans installed.


I'm really jazzed now!

That's awesome, you're gonna be feeling some major power gains after tomorrow that's for sure.

xBRANDONx said:

That's awesome, you're gonna be feeling some major power gains after tomorrow that's for sure.

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Yup, Yup, and Yup!
Its all in!
I like it!
Now I can chirp my rear tires a little on dry flat pavement on take off.
On my way home last night I turned a right hand corner from a red light, and just blipped the throttle, and I almost went sideways.
I feel drunk with the power!
Time to take it easy now.

I have a slight vibration in one of my fans, so maybe today, Ill remount it.
Other than that it was good! I didnèt have to remove the rad at all to change the crank pulley, it was like what Atomic said in another thread, just pull the shroud and remove the fan, and you can get to it. Piece of cake!

They sent me a flex-a-lite temp controller, and it works good, just dialed it in to the exact same stock temps that I was running before. I was surprised at how easy it was to adjust and how well it works.

Today Ièll wire in a manual switch to the efans and an active on indicator in the dash.

Its kindof too bad that I did the BB Tune, underdrive pulleys and efans all at the same time. It may have been good to do each one a week at a time to feel what each mod did for me and report back, but the snow is about the fly soon! Time to get sh*t done! I still have to swap out a 71 Oly motor for one of my boys machines before it snows. HAHA.

The underdrive pulleys work really well, the ALt pulley was the easiest to swap over. The crank pulley is way smaller than stock, and the alt pulley was a little bit larger than stock. And after keeping an eye on the ODBII scan gauge voltage reading(Donèt trust the dash gauges), the voltage is 14.8 at 800rpm, drops to 13.4 at idle. When the efans kick on it drops to 12.1 at idle. So overall, I think that my ALT will be ok. BTW, I did need a new belt. I had to buy an 07 Avalanche Gatorback belt.

I had to go to the dealership and spend $50 to get the Crank Relearn Procedure done on the new BB computer. It threw up P1336 as soon as it started, even after clearing the codes myself, they would come back almost in an instant.

Ièm a very happy camper with no droopy drawers for me!
All thats left this fall is new front brakes.

sounds good man. just plan on wasting some more gas with your foot on the floor! lol

Yea that flexalite thing is pretty amazing. and easy

AtomicHoe094 said:

sounds good man. just plan on wasting some more gas with your foot on the floor! lol

Yea that flexalite thing is pretty amazing. and easy

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HAHa, ya.. At first it was like that, but then I settled down a bit. Just a little bit. After running this setup for a week now, I've noticed a few things.

Fuel economy has gone up. I don't have hard numbers yet, but I can go further on a tank of gas then I could before.

This was the best ~$700CAD I could have ever spent. $136 for the efans, $56 for the temp controller, $144 for the underdrive pulleys, $300 for the BB Tune, and $50 for the crank relearn. $0 Labour. (I never pay anything for labour, I have our shop install stuff for me)

Man, my truck goes now. I have a POSI diff, so it's hard for me to spin my tires because both have to spin. Almost never happened before, ever. As hard as I tried, I had a hard time to spin the tires. NOW, I spin both tires even when I don't want to. I'm still learning how much to get into the throttle on turns. dry asphalt, wet ashpalt, gravel, etc. It's different for each. I never used to have to worry about it, now I'm spinning out all the time. And this is with my foot into it about 20-30%! I can even chirp the tires on dry pavement straight line.

I do alot of highway driving, so passing and cruising speeds are important to me. I find myself cruising alot faster than before, and I'm constantly checking my speed to slow down, because now the truck wants to fly. I can maintain 130kph(80mph) flat level with my foot into it at only 22%, previously it was ~38%. And when I want to pass someone from 80kph, I will floor it and by the time I've passed a transport, I'm doing 137kph. Did it this morning. Old score? About 110kph, If I was lucky. What a feeling of power!

Also, I've noticed, and I have no idea why, that the sucking whah! noise is almost never there anymore. Previosly it was prevelent at 30%TPS and up, now I rarely hear it, only when I floor it. The engine feels like it doesn't work as hard anymore.


I wired up a manual switch and a pilot light in the dash to show me when the Efans are running(either auto or manual). And I have to say, they almost hardly ever come on. Only when stuck in stop and go traffic or idling do they come on. At almost any speed over 20kph, they don't come on. Granted the ambient temps are down to an average of 10degrees celcius right now, I may have to wait until next summer to see how they do in heat. They do seem to cool the engine bay better than the stock fan at idle though. Acording to the IAT sensor, idle temps are cooler now then before at the same ambient temps.

I can't say enough good thing about these mods!

I took some post install pics, I'll post them up soon.

Here are some of the post install pics.

BBTune new Computer;


Flex-A-Lite Temp Controller;


Replacement Alternator Pulley;


Replacement Crank Pulley;


Underdrive Pulleys;


It's a Cavern in there without the Mechanical fan and shroud;


Efan Install;



She aint pretty, but she works!

It's hard to see in the pics, how are the e fans mounted to the radiator? I've looked into e-fans, but all of the "kits" are $500-$600. I do like that they have the aluminum shroud however which helps make them more efficient.

Glad to hear you like the BB tune!

Done Deal DR said:

It's hard to see in the pics, how are the e fans mounted to the radiator? I've looked into e-fans, but all of the "kits" are $500-$600. I do like that they have the aluminum shroud however which helps make them more efficient.

Glad to hear you like the BB tune!

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I too, didn't want to spend over $500 for a kit.

I bought the fans from this Ebay vendor;

And they install via custom plastic zip ties that go through the rad. Each kit comes with four of them, but I only used two at the top to hold in the fan. The bottoms rest and sits in place on the existing fan shroud lip.

There is a possibility of the rad getting punctured maybe, but just be gentle on install. If it causes me any kind of grief I'll upgrade the rad, and think about a shroud.

I was wondering about the need for a shroud that the kits have too. But these fans come with one built-in for it's size. It's not a perfect fit for the rad, and doesn't cover the entire surface area, but if you mount the e-fans close enough to the rad it should be ok. Like I said, they hardly ever come on, just at idle and stop-and-go traffic. Normal hwy driving, they just simply don't come on.

So far, if I had to do this again, I would still pick the cheapo fans and not the kits. It's not worth the extra money. Maybe next summer things will change. I'm sure i'll post updates, if there are any.

It's the last picture on the bottom that shows the plastic zip ties.

I see now, that makes perfect sense. In all actuality, it couldn't be that hard to make an aluminum shroud with even basic tools if you needed it. You can get thin flat aluminum stock for fairly cheap online shipped to your door that can be manipulated quite easily.

I'm in Arizona, so obviously I'm a bit more concerned about cooling performance than you'd be in Canada, but it certainly never hurts to get a bit of extra performance as well. Thanks for the pictures!

Been thinking about electric fans myself and I too did not want to pay a million dollars either... I like this option but not sure by the time it is shipped into the states, that there isn't an alternative available state side.

I did find this on evilbay: http://cgi.ebay.com/ebaymotors/PROCOMP-DUAL-16-INCH-ELECTRIC-COOLING-RADIATOR-FAN-KIT-_W0QQcmdZViewItemQQhashZitem4cf140402dQQitemZ330465034285QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

Are they loud? I have a Spal fan on my race car and its loud as hell. Love it... really pulls some air lemme tell you. The Spal fans come with a gasket that goes between the rad and the fan. The also have some neat mounting brackets available. How easy was it to wire these into the stock configuration and did you how were they activated? Here is Chicago, temps can get pretty brutal (100+ on occasion) so I need a fan that can handle that and not leave me stranded as I do a lot of traveling and hauling with my Yukon. I would imagine that with two 16 inch fans without a shroud... it should cool with no issues.

One word of caution for people thinking about this... MAKE SURE THE FANS YOU PURCHASE ARE PULLING FANS NOT PUSHERS OR THEY WILL NOT WORK FOR YOU!!!