has anyone ran underdrivepullies on their 6.1? if so is the added gain worht the loss of functionality? i'm debating between this and the highflow cat/midpipes mod. which is the best bang for the buck?
I've only heard of underdrive pullies for superchargers. We don't have one. Is there something else you're changing the pully size on?
Probably not a good idea. The PCM disengages the air conditioner clutch at WOT. You probably don't want to underdrive your power steering. That leaves the alternator which doesn't really rob that much hp right?
right, i'm glad you and scott have an opinion on this. all i know is that i want more power, however it sounds like too big of a pain in the arse to deal with. thanks for the info. whats your opinion on hotchkis sway bars and coils? the sways are supposed to beef up the fron by 30% and the rear by 150%. is it work the hassle of the install?
People have dyno'd completely removing the serpentine belt. Removing the belt (as in, turning the accessories at 0%) "created" a gain of 22HP. In other words, the accessory belt at 100% of normal speed consumed 22 HP that could be freed up. So how much HP can be freed up if you underdrive the accessories at 95%? What about 90%? Or even 80%? I'm guessing an underdrive pulley will save you somewhere from 2-3 HP. Tops.
Motoblue does have a pulley out or soon to be out but on NA applications cost vs any possible gains is not worth it, plus their could be issues with toner ring failure due to do bad harmonic vibrations with a smaller pulley plue what it does to the accessory units and not fully charging your battery at idle, I have seen a few 5.7 Hemis with the MB underdrive pulley they grenaded their toner rings, just FYI
Here is some good reading on the debate: http://www.atiperformanceproducts.com/products/dampers/damper_dinan.htm
yeah, it seems like a waste of time and money. i hope yanking the belt at the track with give me a tenth, i'll only make one pass to find out. bring that beast to kil-kare sometimes! have you ever been there?
Basically, it's not worth it Ben. You want more hp add some juice, a nice 100 shot should really get you moving!
the social stigmatism of a bottle... the std jokes, baby jokes..etc! i want to run naturally aspirated, besides i'm new to most of this stuff. i thought hemis didn't like the juice?
No, they run fast on nitrous, very fast! I understand about not wanting it tho, it's just a relatively quick and easy way to add LOTS of power.
Question though; it looks like the Motoblue piece has an SFI approved dampner (harmonic balancer) attached to the crankshaft pulley therefore the vibration would not occur. I know that some pulley systems, i.e March, do not come with a dampner attached to the crankshaft pulley and you get wicked vibration and will have engine problems later as the previously attached article link suggests. The Steeda pulleys for my 01 GT included a SFI approved dampner attached to the smaller crankshaft pulley and was dyno proven to free up between 8-10 hp so is the assumption that a comparable pulley set for our the 6.1 will not see the same type gains? Just asking....
i was told by "a vendor" that i would gain 14hp. if that were the case wouldn't i be losing @65% of the power to my accessories?
I have both..and if you like the twisties they are both awesome upgrades! Here is what I have Coilovers http://www.bmcspeedshop.com/product_p/eib-2873-711.htm Sways http://www.bmcspeedshop.com/product_p/hp22101.htm Strut Tower Brace http://www.bmcspeedshop.com/product_p/csb1102.htm
These are 6.1 toner rings: 6.1 has a 4 bolt pattern, 5.7 has 3 This is a 5.7 toner ring that blew up because high revs and rpms above stock What it does is it tells the PCM the location of the crankshaft. off of the crankshaft position sensor. bassically it creates a small electrical signal every time one of the little bumps passes the sensor. and that is how the PCM knows the location it looks for the big bump and the big recess. it allows the PCM to fire the fuel injectors and fires the spark plugs. after it sees a cirtian signal. From the outside looking in. It appears that the Motoblue pulley doesn't provide proper harmonic dampening. Harmonics are a natural acurance inside of every engine. But if they are not controlled it leads to premature parts failure. Valve springs are very suseptable to harmonic damage. We have the benifit of a bee hive type spring. (low harmonics/ self cancelling design) Either way. Upgraded toner ring or not. I would not let those harmonics go unchecked inside of my engine. It's your choice.
