Finishing up installing a D1sc on my '89 IROC. It has the 4.25" pulley on the blower and the pulley on the crank is the same size as the OEM serp belt crank pulley.I put the blower belt (supplied by Procharger) on and the belt is still fairly loose with the adjustment bolt tightened as far as it can go.I can still just about take the belt off the idler pulley by hand the way it is.I can also turn the blower pulley with a wrench very easily with little to no resistance from the belt.I swapped the larger idler pulley with the smaller tensioner pulley and it gave me a bit more tension on the belt but the adjuster is still maxed out.If the belt stretched at all,I would have no adjustment left.The belt is a Gates pn. K080660, 8 rib,1691mm long.I could get a shorter one but this one was a bit snug just trying to get it on.You can twist the belt approx 1/4 turn as they say,but the tensioner bolt is turned as far as it can go.Everything appears to be installed correctly.I haven't phoned ATI yet to ask them about it.Just wondering what other people have found.Like I said, with the pulleys the way they were originally,the belt was pretty loose with no adjustment left.Is the belt supposed to be on the loose side as compared to the OEM serp belt,which is much tighter? (engine has not run as of yet)

Thanks for any input

 

When I recieved my F1 with 5" pulley my belt was to long.

I think I have a 4.25" pulley at home and a belt so I can check how long I used with it. I also have built my own spring loaded tensioner for the ATI setup to avoid belt slippage. Search here on power adder for a post about it.

Now I'm also building a new bracket becaurse I dont like the thing with the long bolt that hold the bracket from ATI. I have bent a few of them........

I will also test to rerout the belt to avoid the al.bracket to bend like it does under load, more info will come ifit works.

/N:

 

I find to get the best tension you pretty much have to find a belt that you have to take off your blower pulley and wrap the belt around that then try to get the pulley back on the shaft lol. The ATI tensioner system is pretty much **** for our cars.

gta324 keep us posted on your results

 

I have to do something as the car is running now and something isn't right. It runs fine, but the blower sounds almost like it has rocks in it (so to speak) at idle.It kind of seems to be ok when sped up??Makes a loud snapping noise at times as well.If I grab the blower pulley with the belt on, I can turn it over & the belt will spin around the crank pulley fairly easily.This is with the tensioner maxed out like I said. I think some of the noise may be the belt slipping then catching causing the blower pulley to be "jerked" around so to speak. I'm not sure about the growling type of noise, it was late last night & will have to look into it again tonight.

Should these things just make that whistle type noise at idle or is there some other inherent noises associated with it? I'm not sure & don't want to drive it just yet.Everything has been assembled correctly & rechecked numerous times.Nothing was rushed and I am very particular about making sure everything is right.

Should the blower belt tension be similar to the engine serp belt tension?...as a general rule of thumb I would think so??...because right now it's not.

I will be phoning ATI tomorrow to see what they say.

Thanks again for anyones input, any & all is welcome & useful.

 

Ok, ran it again tonight to re-evaluate the possible noise concern. When it's first started cold,doesn't seem to bad (could just be my imagination as well) Once it warms up, you can really hear a rattle type noise from the intake side of the blower.Put your ear right up to the air filter & that's where it's most notable. Maybe it's just the normal noise they make at idle (it's not the whine/whistle) I'm not sure?
The belt is definitely too long, runs fairly smooth at idle, speed it up to 2,000 or so & you can see the belt just flapping around quite badly...then this is when it can make that snapping noise.I'm pretty sure it's the belt slipping then catching.
Still, if anyone has had any similar situations or advice, much appreciated.

 

Pretty sure the noises are normal except for the snapping one but like you said probably the belt. That intake rattle noise on mine is the collar from the bolt holding the intake impeller, not sure why but its kind of loose but I'am guessing thats normal to.

Yeah you have no tension if you can spin the belt like that, I got a couple of ideas for you that you can try. You can cut your tensioner bolt some so it doesnt bottom out or stick some washers under the head. Another thing you can do is redrill a new hole for the tensioner pulley and move it up another inch to take out some of the slop but first thing you should do is get a new belt.

 

call ATI we sold a setup and installed it they sent us the wrong belt with the kit just double check with them

 

I phoned ATI, they said the "rattley" type noise from the intake is normal. Went to NAPA and after trying 2 belts,found one that works...it's a bitch to put on though. The snapping noise is now gone & the belt stays flat with rpm. The guy at ATI said it should be as tight, if not tighter then the engine serp belt.

Drove it for the first time today, not alot of change below 3,000 rpm,but then the boost comes on and pulls hard. I only got 6 - 6.5 lbs of boost and the fuel pressure was in the mid 60's, MSD was set at 2 degrees retard. Looked like a little bit of black smoke (not much) so I think it's a bit rich. The manual says around 9 psi should be 70-75psi fuel and to turn the valve on the FMU out (counter clockwise) 1/4 turn at a time. Also says to rich can cause low boost levels as well. This kit was spec'd to be 8-10 lb of boost. So I'm hoping to tune with the FMU a bit & see what happens. I know the proper way is a dyno & data logging it, but for now use the FMU & see if that will get the boost to the 8-10 lbs it's supposed to be.

....and the front end of a very expensive Porsche looked good in my rear view mirror...not more then 5 minutes after I took it out for the first time

 

Hey congratulations on your first run!

What rpm did you make your 6Ibs at, also what kind of gauge your using?

 

Not sure what rpm it was at, too busy looking at the fuel pressure gauge,boost gauge and the road...and for cops...but I'm guessing it was around 4500 - 5500rpm??. The fuel & boost gauge's are brand new Autometer Phantom. The boost gauge is the boost/vac gauge with memory and peak warning. Turned the FMU back 1/4 turn and MSD set to 1 degree.Still only getting approx 6.5 lbs boost at the most.Didn't notice any black smoke this time. I have to check the base timing on the engine and will probably turn the boost retard to zero & try that.Probably have to phone ATI again & ask about my set up/pulley sizes to find out exactly what it is supposed to make.

 

Maybe your pulley is slipping is there black rubber dust around your blower and on the bottom of the hood?

 

You need to pay close attention to RPM. 4500 - 5500 can make all the difference on the boost level.