Around the price of the blower

 

We've gone down this path on a C5. First the "J" bracket will need to be replaced with something stronger. The "J" design will break. We snapped a C5 bracket, and the C5 design is much better than the f-body. Second, you will need a cog set up regardless just to turn the F2. We have found that if the blower has its own dedicated belt you can get away with using a 30mm cog drive. You can get the 30mm cog crank pulley from ATI, its part of their C5 kit. You can also get the kevlar belts in 30mm, I think they are called Pollychain. Finally, I would suggest getting the ATI SuperPulley, which is a cog overrun or sprag clutch pulley for the blower. It allows the blower to free spin when you let off the gas or inbetween shifts. This pulley will be a life saver for your belts. I believe this pulley currently only comes in one size and only in 50mm wide. We had to mill it down some just to fit the brackets.

Just so you know with the 402 you plan on running and the pullies I suggested above you will be at 30+ psi of boost. Thats where we were with a 408 and L92 heads.

Good luck and be prepared to break ****, the F2 is one bad bitch.

 

Man that's a lot of very helpful info, Thanks a ton. 30psi is a lot, I'm glad I decided to go with the lsx. Is it crucial to get that ATI Superpully? I know it will help but I was hoping the Procharger race bypass would be sufficient because I just purchased the standard ati damper. The race bypass is said to be good to 2200hp and I don't plan to go near that.

 

Well, first the SuperPulley has nothing to do with the bypass or damper. You absolutely need the Procharger Big Red Race bypass, thats a given. What the superpulley will do is reduce the stress on everything(belts, brackets, crank) during decel or shifting. It takes I believe 100+ hp or maybe more to turn the F2, so imagine trying to slow that thing down from redline. It creates a lot of stress. The superpulley which goes on the blower will allow it to freewheel like a bicycle. So you have the standard ATI Superdamper, thats fine because as you know the f-body has a dedicated belt for the blower, which you want. Similar to your old kit the 8rib crank pulley bolted to the front of the damper. The same goes true for your cog set up, just buy a cog crank pulley to fit, the wider the better. It will just bolt to the front of the damper as before. Now you will have the same belt configuration as before but using a cog drive.
Hope that makes sense, maybe I wasn't clear enough before.

Just an FYI, try to make a blower bracket that has four bolts instead of the three like the J bracket.

Oh one more thing I forgot is that the C5 we developed didn't use an intercooler so since you are using one you should be able to reduce the boost some pushing through it.

 

Just FYI (agreeing with these guys) an F2 is a whole different animal than even an F1r. The F2 will blow your stock brackets apart, even at idle, not to mention the strain it will put on all of you accessories. A 12 rib would have to be sooooo tight it will probably kill your water pump, alternator (and brackets) etc. I would go cog (procharger won't normally sell 12 rib f2s much anymore unless you ask, but it WILL slip) and put it on it's own drive. If you've ever seen an F2 in full action, you'd understand. If you are concerned about a $400 pulley, you may be in for a surprise when you start putting the rest of the custom stuff together. If you aren't going to spin the F2 hard, you may be better off in an F1r.

 

Good point!

 

I gotcha, I was thinking the superpully goes on the crank and for some reason was thinking of it reversed like it would allow the blower to slow spinning even with the crank still spinning fast to reduce the boost pressure like the bypass will. I understand now though, that sounds like a great investment, it will probably be way easier on the blower too, to let it slow down on it's own rather than "braking" it with the crank speed. That means it's going to be blowing a ton of air through the bypass. What's that going to sound like, a long *** whoooooooooooooosh! Thanks, you've been a huge help.

 

I'm deffinetly going to beef up the way it's mounted, not sure how yet but I'm pretty creative. I don't mind putting some more money in for a cog set-up, I just don't like paying more than what I think things should be worth. I know custom allways gets expensive, I just figured there would be some of these parts already manufactured and I would have to do some custom stuff myself with the bracketing. Thanks for your input though. I have considered selling this F2 for a smaller blower but I would really like to have a set-up that's not too common and make it work. It's kind of a challenge for me. Plus I got a great deal on this blower, paid less than what the F1 goes for. If someone really wanted to take this project on and has a F1, I may trade + cash. I doubt it though so I'm going to try and do it the best I can.

 

Alright, I'm on my way. I decided cog is the only way to go after all your guys help.

I found the super pulley you're talking about, it's ****** awesome and seems to be well worth the $500 it costs. It only comes in 75mm right now, does that mean I will have to use a 75mm on the crank as well? It doesn't sound like a bad idea actually if they make one to fit on the ati damper I have. If thats the case then I can use a 70mm belt, shouldn't have any more issues with belt slip. Where can I get this pollychain? Thanks for all the help. This thing is going to way surpass my original goals.

 

No you don't need to run a 75mm crank pulley. Just run the size you need to match the belt that you are able to fit in there.

 

One thing that I will add is to make sure that you have ALOT of belt wrap on the crank and blower pulley. We found on the C5 with little wrap on the crank (about 35%) that it would slip the belt and rip the cogs right off. We went to about 80% wrap on both pullies and it was much happier.

 

Thanks, thats helpful info. I think the way mine will be set-up, I should have about 60% on the crank and 80% on the head unit. Hope that will be enough, other wise I'll have to add another pulley by the crank.

 

A lot of good info here! Bob

 

Bro-do you think the 30mm cog belt is enough to spin a F1R and all the pulley's?

 

Its hard to say. He broke everything with the F2 on a 30mm running all the accessories. Initially, the idler pulley broke at idle, then went the power steering pump bracket, then went the alternator bracket. He actually used a heim joint to hold the alternator from flexing and moving. I posted some pics of the round 1 trial set up below. The heim joint worked nice, it allowed us to center the belt on the pullies. After he got that fixed, then it tore the center out of the water pump pulley, twice. He also went through a fair number of belts during testing because of all the flexing and not enough wrap on the crank pulley. So after all that the power steering went in the pile of unused parts, along with the AC. X-RACER made a custom alternator bracket as you have seen in previous pictures that mounted the alternator backwards and ran off the AC crank pulley. So now the blower had its own dedicated belt (still 30mm) that just touched the water pump pulley enough to spin it. Now in this current set up the 30mm is working just fine.
Here is a link to the current pics:
https://ls1tech.com/forums/showthrea...835&highlight=

And the ones from the first set up

 

Oh yeah that was with the L76 intake that was limited to about 5500 rpm so he switched to a sheet metal. The stock LS2 throttle body would also shut under boost.

 

Man, thats a lot of pulleys, trying to keep it a street car huh. Lucky for me, mine is more drag race oriented, so The only pulleys I have to worry about are the head unit and crank. The alternater will be on its own belt and that's it, all other pulleys deleted

 

Well this is still a street car and he plans on getting all the accesories back on this spring. Thats is why I stated that if you can get a dedicated belt for the blower you will be much better off and in your case the f-body already is set up that way. Unfortunately the C5 does not have that kind of room with out moving the rack and spacing the blower way out.


On a side note what ever happed to the Cartek car they were building? kinda fell off the list and haven't heard much lately. Any updates?

 

If your going that route, your going to wanna get a ATI superdamper for an ls1 f-body with a big block bolt pattern, that will give you the most options for cog crank pulleys( you can get them right from procharger then). If you have the room go with the 50mm setup, more strength and better belt options. You can run the kevlar belt but you cant back bend it( so the tensioner will have to be on the tooth side). The boost on that thing is going to be high, im spinning mine at 54,000rpm at 7000 rpm(engine) and im seeing over 30psi on a 408. It made 1217rwhp on E85 with about 14deg. timing, but i had problems lifting the heads.

Best of luck! Post up if you need help on anything!

 

Thanks again guys, I just wanted to follow up. Shouldn't have any belt slip now




The last one is for a big block, my engine builder is making it work on my ati damper. With these pulleys at 7000rpms I'll be at 60000 for the blower It's rated at 65000 but I think this is a good starting point.