I have a LT1 that's stroked to 383 with edelbrock LT4 heads and intake, blowercam, procharger 600b with 2.55" pulley. The engine is built to rev to 6500-7000 rpm
The problem is that i have beltslip over apprx 5500 rpm. I rebulit the belttensioner to at static one, and used "belt-glue" (or what's it called in english). That helped a littlebit before a got beltslip at 5000 rpm. Today i tried to to increase the belttension but what happend is that the belt broke.
What is there to do? Better kind of beltglue? Cog or chaindrive? other sugestions?
Yes it's to small to deliver max hp, since islandflow is in the 25k-30k rpm region and it will be somewhere over 40k at 6000rpm. so i will lose a whole lot of adiabatic efficeincy.
No, it's not to small to suffer from "overboost" = it will need less power at 5500 with a 383 than it do with a 350. as can be seen in the diagram, green line is for a 350. a 383 will go through islandflow.
But it's quite likey that if i changed to a D1 that i still would have problem with beltslip since i need apprx the same power to produre 12psi of boost as with a 600b. The internal stepup is higher (wich will help) but will it do enough?
I'm sorry that i dont have my P600b compressormap handy, but the P1 is very alike.
are you running the stock intercooler on the procharger kit? That thing has got to be taking away boost at your level. How much boost is the kit making currently when it starts to slip? A 2.55" pulley is tiny. I can't even keep a 2.75" pulley from slipping. Have you increased the belt wrap on the pulley?
Also, belt glue is only a temporary fix. You need more of a permanent fix. I've used Anderson's "insta-boost" at the track before, but it didn't help much at all.
Yes it's to small to deliver max hp, since islandflow is in the 25k-30k rpm region and it will be somewhere over 40k at 6000rpm. so i will lose a whole lot of adiabatic efficeincy.
No, it's not to small to suffer from "overboost" = it will need less power at 5500 with a 383 than it do with a 350. as can be seen in the diagram, green line is for a 350. a 383 will go through islandflow.
But it's quite likey that if i changed to a D1 that i still would have problem with beltslip since i need apprx the same power to produre 12psi of boost as with a 600b. The internal stepup is higher (wich will help) but will it do enough?
I'm sorry that i dont have my P600b compressormap handy, but the P1 is very alike.
You need a dedicated drive (belt) for your blower, probably an 8-rib conversion. The P600b is small for your engine and I think the smallest head unit that you can get a fix for is the P1SC...you might be better off going to a larger blower pulley until you can get a blower drive conversion. do some searches on this site for how this issue has been resolved.
the most important part of resolving belt slip is the surface area of the Belt coming into contact with the pulley and the belt wrap.
The 8-rib setup in a dedicated drive configuration would be ideal, but you got to make sure the pulley is cut properly. If the peaks and valleys in the pulley are off, you'll continue to have belt slip.
I would add a few idler pulleys to the existing configuration trying to wrap as much of the pulley as possible (like like something close to 270 degrees of belt wrap, or even 315 degrees of belt wrap).
you "might" also have a restriction in the intake track or discharge tube. i would also study these components as it is commonly understood that a restrictor plate will cause belt slip (limiting boost).
to the other members:
we know that the p600b is a small head unit for the 383 (will not support the needed cfm), but the OP's objective is to eliminate slip, not get a new head unit (which won't help with slip).
the most important part of resolving belt slip is the surface area of the Belt coming into contact with the pulley and the belt wrap.
The 8-rib setup in a dedicated drive configuration would be ideal, but you got to make sure the pulley is cut properly. If the peaks and valleys in the pulley are off, you'll continue to have belt slip.
I would add a few idler pulleys to the existing configuration trying to wrap as much of the pulley as possible (like like something close to 270 degrees of belt wrap, or even 315 degrees of belt wrap).
you "might" also have a restriction in the intake track or discharge tube. i would also study these components as it is commonly understood that a restrictor plate will cause belt slip (limiting boost).
to the other members:
we know that the p600b is a small head unit for the 383 (will not support the needed cfm), but the OP's objective is to eliminate slip, not get a new head unit (which won't help with slip).
The P600B requires a tiny pulley to make boost, and the small pulley has less belt wrap surface on it, which makes it easier to end up with belt slippage.
The P600B requires a tiny pulley to make boost, and the small pulley has less belt wrap surface on it, which makes it easier to end up with belt slippage.
the build of the camaro that you guys got at the shop is nice! I would like to know the specs on the pistons as many people shy away from a 396 when it comes time to boost it.
the p600B is small, and does require a small pulley to support the needed CFM (boost), but just like you mentioned, it boils down to trying to modify the brackets for idlers (translating into sufficent belt wrap).
the F1A is a "sick" head unit, capable of supporting something north of 1600cfm! the step up ratio is much greater than the P1SC's as well (5.4:1 compared to 4.10:1).
I don't recall seeing an F1A ever used in a y-body application, but I have seen a V-7 YSi headunit on a y-body using Greg Carrol's bracket. The YSi essentially supports about the same amount of CFM as the F1a, without the awesome step-up ratio and the additional RPM's the F1A can support.
yes the belt is slipping at the blower. Today i have slightly over 200 degrees of wrap. I se about 7psi of boost. Earlier i used the "stock IC", we saw about the same boost before and after the IC.
Also we had "intake swirl" so when we got to 4500 rpm (5psi) boost stared to drop slowly to about 1psi at 6000rpm. That was fixed with some fiberglass in the intake. Once that was fixed i got beltslip instead .
But is i possible to use a 8-rib in a LT1 corvette? I can't move the headunit forward mote than 1/4-1/2"(it hits the radiator).
does anyone have any clue how much torque it takes to drive a blower at maximum boost?
yes, it's possible to use an 8 rib setup on the procharger stuff. Heck, without the opti, you can run up to 12 rib.
Your intake swirl sounds like a really bad case of belt slip. I had something similar when I first started and my car had a 4 rib belt(!) on the blower.
Blowerworks has an 8 rib conversion for procharger head units. I believe they support the P1sc and D1sc, would need to check p600, but would imaging they all have similar bolt patterns.
You need to buy brackets and upgrade to an ATI balancer with a dedicated 8 rib. The blower pulley runs closer to the engine so the head unit ultimately moves away from the radiator, not closer.
The accessories run on their stock 6 rib belt.
I am planning on this upgrade myself in the near future.
I'll let Greg speak to more of the details.
As a side question, I would be curious if you had any luck pushing more boost through your procharger intercooler, I am considering upgrading that also as ATI says they will limit boost and power due to too much restriction.
Blowerworks has an 8 rib conversion for procharger head units. I believe they support the P1sc and D1sc, would need to check p600, but would imaging they all have similar bolt patterns. ....
Completely different case (and bolt pattern) between the P-600B and the D1 head units.
I think I remember ATI saying they were, the main difference was a D1 has a larger outlet diameter, but would bolt to the same brackets.
The P-1SC and the D-1SC both share the same housing, inlet and outlets are identical in size. The P600B is totally different, and even uses a different bracket. Bob
yes the belt is slipping at the blower. Today i have slightly over 200 degrees of wrap. I se about 7psi of boost. Earlier i used the "stock IC", we saw about the same boost before and after the IC.
Also we had "intake swirl" so when we got to 4500 rpm (5psi) boost stared to drop slowly to about 1psi at 6000rpm. That was fixed with some fiberglass in the intake. Once that was fixed i got beltslip instead .
But is i possible to use a 8-rib in a LT1 corvette? I can't move the headunit forward mote than 1/4-1/2"(it hits the radiator).
does anyone have any clue how much torque it takes to drive a blower at maximum boost?
Rest assured your belt slipping is NOT at the the blower pulley. It happened at the bottom of your crank balancer. All the die hard blower LTX guys will agree and understand what I am talking about. Take the advices from the people who has been thru this very same problem you got it now. Save your $ and get a 8 rib conversion done and you are done and happy with your ride.
The 8 rib conversion here, you are often hear about is that the blower is driven by it OWN BELT that mean your balancer will have a total of 14 ribs, 8 rib is for the blower it self and the other 6 ribs is your factory belt. The 6ribs blet routing is remain the same as the factory configuration. So, your blower will NOT need to move forward toward the radiator. The blower will actually need to move inward toward the engine firewall. Understand now?. Based on the last post you write, you clearly did not understand how the 8 ribs conversion is done. Good luck.
PS. With this conversion, it cranking out 14.2 PSI of boost on the dyno on a 383ci and untuned mode, only swap out the small injectors with a 50s injectors, it making 544rwhp, It could have easily hit 600rwhp with correct tuned. Of course this is done with a D1SC blower. I sold the car and this is the experience I share for you guys. I forgot to mention, 14.2 PSI of boost at only 4500rpm. 3.0 in blower pulley and 7.6" balancer going thru ATI IC. ATI IC is not the best but better than nothing.
You can not reuse your original bracktry and your spacer will NEED to be shorten and need of new bolts.
Here is a pic cog conversion I had done and the 8 rib is the same principal.
If I ever do a blower LTX in the future, I do it with 12rib like BrandX on this forum. 12+6 + F1R = nice.
This is what my original Prochrager bracketry look like, as you can see, it look weak and not so clean look, compare to the conversion one.
Now I thought about it, in this picture, I should have used a cog pulley to mate with the inner cog belt to longevity, but that was than.
The dedicated 8-rib is the fix for LT1 belt slip issues. If you're looking to go to the next level, a dedicated 12-rib has no belt slip issues and it has none of the downsides associated with a cog drive...something to think about.
Like Bruce said, the dedicated 8-rib is the fix for LT1 belt slip issues. If you're looking to go to the next level, a dedicated 12-rib has no belt slip issues and it has none of the downsides associated with a cog drive...something to think about! For 12-ribs, you will need to shave your optispark distributor cap and go to a coil on cyclinder setup like LTCC or Delteq (ran a LTCC for awhile w/12-rib and opti, it worked fine)...currently running a Dual-Sync Distr with Gen-VII DFI
Like Bruce said, the dedicated 8-rib is the fix for LT1 belt slip issues. If you're looking to go to the next level, a dedicated 12-rib has no belt slip issues and it has none of the downsides associated with a cog drive...something to think about! For 12-ribs, you will need to shave your optispark distributor cap and go to a coil on cyclinder setup like LTCC or Delteq (ran a LTCC for awhile w/12-rib and opti, it worked fine)...currently running a Dual-Sync Distr with Gen-VII DFI
Brand-x! You are saying that the 8 rib can be ran without shaveing the opti. Correct?
And would you have a price, what it would cost to do the conversion?
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Beltslip on LT1 with P600b supercharger
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