CI GS

Thanks Brian! I just responded to your email, for which I am grateful.
My apologies for not updating this thread, in that, I spoke to Cam on Friday and he told me he was picking the kit up from Magnuson today.
I'm really looking forward to installing this blower and will no doubt be getting back to you soon for some more parts, or maybe a kit for my truck!

Streetk14

That's good to hear. Figured you'd be pulled even more directions since you took over Magnuson's replacement parts services.

And I hope I didn't come off as implying you don't provide good customer service. You certainly went above and beyond with my deal if you remember

I want to hear how that 1LE is coming too. I was really considering one of those before I got me GS. Just couldn't get over the weight thing.

monsta01

So did we figure out if there really is an 8.25" ATI pulley setup that will work? If so what do I order?

If I go from a 7.9 IW to an 8.25 ATI would that give me 20+ hp?

I'd like to see this pulley combined with a set of TFS255s if the pulley actually exists, is on the shelf and will fit

CI GS

Yes, there is a 8.235" balancer shell that's designed specifically for the Y-body. Summit lists it for just over $350 but they don't have it in stock and it looks like they will have it dropped shipped from ATI.
Unfortunately, I haven't been able to find a part # for an assembled 8.235" balancer.
Given those circumstances, your best bet would be to contact ATI directly and ask them to build you a complete balancer using that shell.
I have no idea what boost or HP gain that would give you. I think the TFS heads will net you a decent gain in power throughout the RPM band.

CI GS

Picked up the H-Beat from DHL today!
Apparently, Magnuson sent it direct to me instead of shipping it to SCOL, so it shipped without the BAP. Brain has already shipped the BAP express to me though. The guys at SCOL have been top notch.
Only problem is that the blower came with the standard 96mm pulley, so I'm trying to figure out now whether to get a smaller upper or just go ahead and order the O/D ATI Balancer and be done with it.
Really don't know what to think about Magnuson at this stage...

scottg

Hang in there, they should ship you the 84mm now. Their screw-up.

old motorhead

If you think you'll eventually want that bigger balancer, there's no better time to do it than when you're pinning the crank. Good time for a cam swap too

CI GS

You're a bad influence Rodney!
Funny thing is, that's exactly my thought process now. I've been saying to myself: Well, if you need to pin the balancer, just go ahead and get the ATI and use their pin system, so that you won't have to drill the crank twice.
Then, next comes: Well, hell, if you're going to pull the balancer, you may as well just pull the timing cover and do a cam swap at the same time.
Next it will be: okay, if I have to pull the radiator for the cam swap, then I may as well just go ahead and get that Dewitts that I have in my wishlist on Summit online!
Then, no doubt, once I pull the intake and see the bare face of the heads, I'll say: Oh, what the hell, now that I'm this far down, why don't I just pull the heads and do the TFS head swap too?...
And on it will go, right down through the crank and drivetrain all the way back to the Z06 diff. Such is the plight of many a well-intended "mild modification" initiative.
And it's all because I've got an old motorhead voice in my head now...

CI GS

On a serious note: I really don't like the stock balancer, and would prefer to change it now.
If I do go with either an 8" or the 8.235" balancer with the 96mm upper, I just need to figure out what upper pulley would produce a comparable ratio using the stock 7.5" balancer, so that I can have an idea of what kind of boost the bigger pulley combo should produce?
I'm thinking about what Ken said as well - that it's always better to increase the size of the lower pulley.
Let me try to do some math...

scottg

CI GS Like I said "welcome to our world". Please hurry up and get your mods done. I"am now living through your thread and I haven"t got my car in yet for this years mods. Cam is next if I can 45whp out of it without meth. And head work.

CI GS

Okay, here goes. I did a little mental masturbation (math) and came up with the following:

Firstly let's look at the ATI balancer/drive pulley options:
"Stock" dia. -7.53" = 191.3mm
"8 %" overdrive - 7.96" = 202.2mm
"12%" overdrive - 8.23" = 209.2 mm
By converting inches to mm, even simple folk like me can calculate the various drive ratios for the sake of comparison:

Therefore, to show the difference between the three available sizes of balancer/drive pulleys with the smallest available C6 pulley:

209.2\81 = 2.58:1
202.2\81 = 2.48:1
191.3\81 = 2.36:1

This also allows me to determine that with the largest balancer/drive pulley and the 96mm blower pulley (2.18:1), that would be the rough equivalent of me running the stock sized balancer/drive pulley and an 87mm blower pulley (2.2:1). My guess would be that this would put me somewhere around 7-8psi of boost on my car with the stock cam and headers.
So, in short, I still need my 84mm pulley!
Maybe one of you guys can check my math and correct the above if I've gotten it wrong?

scottg

I just replaced stock hb with ATI same size as stock and 96mm pulley, was at 6lbs, put on 84mm and was at 9lbs.

CI GS

Thanks. 9 lbs would be good for me for now. I'm thinking that's what I will do and then in the future upgrade to either the ATI 8-rib 8.235" shell or the IW 8" balancer.

BTW: How did your guys pin your ATI balancer? Did you use the ATI fixture, or the Magnuson crank pin kit? The other thing that concerns me a bit is if I pin the crank now with the included kit, when I switch to an ATI balancer in the future, I will have to pin that again, probably using the ATI pin kit, which by the way, will cost me an extra $139.

Just by way of update: The SCOL guys have already emailed and said they are sending an 84mm and a new belt. I really can't say anything bad about those guys.

I'm going down to the garage now and start tearing into this project.

scottg

DRM did mine so I don"t know. Good luck on your project

Streetk14

Stock balancer and 90mm pulley put me at 7-8 psi with headers on an otherwise stock LS3. I'd think you'll have a little more than that with the equivalent of an 87mm pulley.

CI GS

Thanks. I decided that for now I'm going to just pin the stock balancer and use the 84mm upper. That will give me some time to figure out what to do about the balancer. I'll probably do a cam swap at the same time.

Streetk14

I kind of wish I'd thrown an ATI balancer on it when I pinned the crank, but I'm pretty sure I could re-pin it if I ever do buy one. It would cool if I had a junk crank sitting around to drill the ATI balancer using the Magnuson crank pin jig, then it would just be a matter of lining up the pins during installation. Just don't want extra holes in my crank.

With that said though, it's a LOT easier to just pin the crank vs. changing the balancer or doing a cam swap. With the intake manifold removed, it should be a breeze. Just remove the motor mount nuts and jack up the engine. Gives you more than enough room to get the crank bolt out. Getting the rack out isn't much fun if you have a power steering cooler setup like we do. The lines seem to be more of a bitch.

I'd probably pin the crank now, and do a cam AND balancer at the same time whenever you're ready. Or do them both now... but I've learned to try to do things once step at a time for diagnostic reasons.

CI GS

That's been my dilemma too. Don't want to drill two slots in the crank now and then have to re drill and pin the crank again in the future. Using an old crank is a pretty ingenious idea. No wonder Rodney says you're always right!
I do have a power steering cooler. I looked everything over today, but didn't get to start anything, as some friends came over and that killed my day of wrenching (it's a public holiday down here). The steering rack is by all accounts a major PITA and I only want to have to pull that once, so I would wait until I do a cam swap. I don't want to do that now, as I think I'm already going to stress my tuner to get the tune tweaked via emailed data logs.

old motorhead

So...if you change to the stock size ATI balancer, can't you change just the outer shell if you want to go o/d? No worries with pinning and repining that way?? That is....until you swap the cam....

CI GS

Hey Rodney. I've considered that option too. Truth is that I'm just being cheap about it. If I buy the stock dia. ATI now, I'll pay ~$450 for that, plus about another $200 in shipping and import tax (27% of CIF). If I also buy their pinning kit, that adds another $140 plus incidental costs. The O/D shell then adds another $350+ freight and tax to that. Before I'm done, I'll have like $1,200 invested in a harmonic balancer.
And, of course, changing it now will also require me to pull the steering rack, which I'm trying to avoid until I go at the cam.
So, I'm thinking that I'll go with the stock balancer for now, pin it with the Magnuson kit, and when I go with a cam in the future, that would be the right time to install the O/D balancer, as that would also allow me to regain boost lost from the cam change anyway.
In the meanwhile, I can figure out whether I need the headache of piecing together an ATI O/D balancer, just to get another .235", or whether I just buy an IW 8" and be done with it.

BTW: I've asked Cam at SCOL to look into what options are available from Magnuson for a throttle body upgrade. I gather they may be offering the SW 108mm, but I would like to know if they have an inlet snout for the NW 102mm, as that would be (for me) a much more viable option (since the NW is about half the price of the SW). After looking closely at the base HB snout, I think the reason that monsta01 didn't see any improvement with the 102mm TB is because you simply can't port the 90mm snout out enough to accommodate the 102. I'll report back here what I find out.