LT1 Crankcase Vacuum Pump Kit in Development
Teching In
Joined: Mar 2011
Posts: 9
Likes: 0
Looks great..I need some larger valve covers also...where did you get those? They look good..how much vacuum do those pumps pull? Do you think it would be a enough for mine with the turbo? I hope you find a shop that can make those brackets ..let me know how much or if I can help you with any expense ..this will help me out big time.
Looks great..I need some larger valve covers also...where did you get those? They look good..how much vacuum do those pumps pull? Do you think it would be a enough for mine with the turbo? I hope you find a shop that can make those brackets ..let me know how much or if I can help you with any expense ..this will help me out big time.
Teching In
Joined: Mar 2011
Posts: 9
Likes: 0
To my surprise, the stock length (64") belt fit perfectly. But that's if you use everything I used. My crank balancer diameter is 5.7" (ASP945100), smaller diameter alternator pulley from ASP, and the 5.69" diameter vacuum pump pulley(300-912). You don't have to get my exact crank pulley, but you need something 5.7" or smaller so you don't over spin the vacuum pump.
The pump I used is from GZ Motorsports. Part number VP101A. I would not recommend getting VP102. It's the same pump but puts the exhaust outlet fitting in a place that might hit the accessory bracket. You might be able to use a 45* fitting to make it fit but I would just use the VP101A.
Sorry I have not found anyone to duplicate the bracket yet. It's kinda hard when all the shops are only open when I'm at work myself. I'll try harder guys.
I got my new valve covers in the mail and some more AN fittings. Next step is to powdercoat all those scratched up black parts
The pump I used is from GZ Motorsports. Part number VP101A. I would not recommend getting VP102. It's the same pump but puts the exhaust outlet fitting in a place that might hit the accessory bracket. You might be able to use a 45* fitting to make it fit but I would just use the VP101A.
Sorry I have not found anyone to duplicate the bracket yet. It's kinda hard when all the shops are only open when I'm at work myself. I'll try harder guys.
I got my new valve covers in the mail and some more AN fittings. Next step is to powdercoat all those scratched up black parts
Thread Starter
Joined: Oct 2005
Posts: 1,687
Likes: 0
From: Fairfax, Virginia
Looks great..I need some larger valve covers also...where did you get those? They look good..how much vacuum do those pumps pull? Do you think it would be a enough for mine with the turbo? I hope you find a shop that can make those brackets ..let me know how much or if I can help you with any expense ..this will help me out big time.
Oh well.. so to answer your question they are $60 valve covers from ebay. The quality is amazing. I've had canton's before and these are just as nice.
I don't expect this pump to not be able to pull enough vacuum. In fact you need to use a regulator to keep it from pulling TOO much. Do not go over 15" of vacuum. I'm going to set mine to 12". That colorful red & blue **** is my regulator. I bought it from STAR Machine because I like their regulators better. I also bought their -10AN bung with baffle (on valve cover) and their bolt-on oil fill cap.
Actually, call up GZ Motorsports and see if they will make this bracket for you. I donno if they kept a template or not. They didn't sound interested in making a bunch of them but it's worth a shot. Just ask for Greg Zucco and mention my name "Ralls."
Thread Starter
Joined: Oct 2005
Posts: 1,687
Likes: 0
From: Fairfax, Virginia
Thread Starter
Joined: Oct 2005
Posts: 1,687
Likes: 0
From: Fairfax, Virginia
Ok everyone. I found a shop that can make the vacuum pump bracket. They will cost me $75 each. Which is pretty damn good considering I payed $100 for mine. Those who are interested in this setup should contact me asap. Even if you don't plan on buying the vacuum pump, fittings, breather, etc right now, I would suggest to at least get this bracket now because I don't plan on doing this very long.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
Thread Starter
Joined: Oct 2005
Posts: 1,687
Likes: 0
From: Fairfax, Virginia
Here are the parts that I used.
-GZ Motorsports Vacuum pump (VP101A)
-Dorman 5.69" vacuum pump pulley from local parts store (300-912)
-Custom vacuum pump bracket
-ASP 5.7" crankshaft balancer (ASP945100)
-ASP smaller alternator pulley
-Custom alternator bracket
-Stock length serpentine belt
-Star Machine -12AN Female vacuum regulator
-Star Machine -10AN fitting w/ baffle for valve cover
-Moroso breather tank (85402)
AN Fittings:
-12AN X 1/2" MPT 90 degree (out of suction side pump)
-12AN nut X -10AN male swivel reducer (after regulator)
-10AN straight pushlock hose end (after reducer)
-10AN 90 degree pushlock hose end (valve cover)
-10AN X 1/2" MPT 90 degree (out of exhaust side of pump)
-10AN 90 degree pushlock hose end (off exhaust fitting)
-10AN 90 degree pushlock hose end (off breather tank)
-10AN push lose hose (4 feet depending where you mount breather tank)
So that is everything I used. You can do whatever fittings you want. The only reason I mixed -10AN with -12AN is because I had left over -10AN from my other crankcase evac setup. Whatever crank pulley you use, it needs to be 5.7" or smaller so it doesn't over spin the vacuum pump. There are a bunch of vacuum pump regulators out there so use what you want.
-GZ Motorsports Vacuum pump (VP101A)
-Dorman 5.69" vacuum pump pulley from local parts store (300-912)
-Custom vacuum pump bracket
-ASP 5.7" crankshaft balancer (ASP945100)
-ASP smaller alternator pulley
-Custom alternator bracket
-Stock length serpentine belt
-Star Machine -12AN Female vacuum regulator
-Star Machine -10AN fitting w/ baffle for valve cover
-Moroso breather tank (85402)
AN Fittings:
-12AN X 1/2" MPT 90 degree (out of suction side pump)
-12AN nut X -10AN male swivel reducer (after regulator)
-10AN straight pushlock hose end (after reducer)
-10AN 90 degree pushlock hose end (valve cover)
-10AN X 1/2" MPT 90 degree (out of exhaust side of pump)
-10AN 90 degree pushlock hose end (off exhaust fitting)
-10AN 90 degree pushlock hose end (off breather tank)
-10AN push lose hose (4 feet depending where you mount breather tank)
So that is everything I used. You can do whatever fittings you want. The only reason I mixed -10AN with -12AN is because I had left over -10AN from my other crankcase evac setup. Whatever crank pulley you use, it needs to be 5.7" or smaller so it doesn't over spin the vacuum pump. There are a bunch of vacuum pump regulators out there so use what you want.
Thread Starter
Joined: Oct 2005
Posts: 1,687
Likes: 0
From: Fairfax, Virginia
That's what I was afraid of. I was trying to get that same balancer but I was told I need a smaller one. Your also supercharged so you have another pulley outside for the SC right? Or how is your belt setup? Cog?
Yeah, I've got the blower pulley furthest out and it's a 12 rib. Hmmm...there has got to be a solution to this...hate to be this close and it come to this.
Thread Starter
Joined: Oct 2005
Posts: 1,687
Likes: 0
From: Fairfax, Virginia
Or could you get rid of your ATI balancer all together? They also do custom balancers.
Yeah, I have a spacer in between the ATI and blower pulley but just went through great lengths to go crank trigger...so using a UD pulley before the ATI may work. You don't have any charging issues w/ a damper being that small? Is that the stock diameter on a LT1?
Last edited by SRZ; May 11, 2011 at 05:43 PM. Reason: pic added
Thread Starter
Joined: Oct 2005
Posts: 1,687
Likes: 0
From: Fairfax, Virginia
This is a new balancer for me so I don't know exactly how well the alt will charge. They say that it will fully charge at 800rpm. That's why I got a smaller alternator pulley to compensate for it so it should charge like normal. Stock diameter is 7.5in I think. I have another idea that might let you keep your crank pulley.
Thread Starter
Joined: Oct 2005
Posts: 1,687
Likes: 0
From: Fairfax, Virginia
My other idea we discussed didn't quite work out. I was able to mount the vacuum pump where the A/C was. The pump needed to be rotated away from the motor to fit a larger pulley (at least 6.8") if you kept your ATI 6.78" crank pulley. I believe it would be too far out and hit the frame rail. However, it looks like you have the Speed Inc bracket which mounts everything way lower. How close is your alternator to the frame with that bracket? I would use your alternator as a template since they have the same bolt pattern and see if a 6.8" pulley would fit.
Here is the pump mounted below. I had to make spacers but otherwise it was just as easy as mounting it up top.
Here is the pump mounted below. I had to make spacers but otherwise it was just as easy as mounting it up top.
