[slowbird]

I'm considering putting a vacuum pump on my GrandPrix, was looking at the GZ pumps from Butler. Read a decent amount of comments on here about them.
My question is anyone run one without a bypass to set vacuum? I'm curious just how much vacuum they can pull and why limit it?

[PAUL K]

You should ask on FB. That is where the experts hangout.

[Formulajones]

Dad's been running a vacuum pump on his for a few years now. Can't remember the brand off the top of my head.

My understanding is that you always want to be able to adjust the amount of vacuum, as too much can be a bad thing. Typically at WOT and max rpm you want to see no more than about 10-12 inches. Depending on how you pulley it will have an affect. I use the valve to dial it in from there. So idle and cruising around under 3000 rpm I'll see maybe 4-5-6 inches at most.

Too much vacuum at high rpm I'm told can pull oil away from things like wrist pins and cause damage. Tony Bischoff gave dad the run down on pumps back when he built his engine and some of those things were mentioned.

After setting it up this way it's been street driven mostly, and raced when he gets time. Lots of street miles, it's been a good setup.

[slowbird]

Originally Posted by Formulajones

Dad's been running a vacuum pump on his for a few years now. Can't remember the brand off the top of my head.

My understanding is that you always want to be able to adjust the amount of vacuum, as too much can be a bad thing. Typically at WOT and max rpm you want to see no more than about 10-12 inches. Depending on how you pulley it will have an affect. I use the valve to dial it in from there. So idle and cruising around under 3000 rpm I'll see maybe 4-5-6 inches at most.

Too much vacuum at high rpm I'm told can pull oil away from things like wrist pins and cause damage. Tony Bischoff gave dad the run down on pumps back when he built his engine and some of those things were mentioned.

After setting it up this way it's been street driven mostly, and raced when he gets time. Lots of street miles, it's been a good setup.

I ran my star pump all out to 9000rpm pulled close to 20" never had oiling issues.
I think it's an old myth.
But I don't believe the GZ pumps are as big or as good as the bigger race pumps so just how much vacuum could one pull at 6000rpm? Most of the posts here have said they are limiting it to 10-12 inches.

[Formulajones]

Originally Posted by slowbird

I ran my star pump all out to 9000rpm pulled close to 20" never had oiling issues.
I think it's an old myth.
But I don't believe the GZ pumps are as big or as good as the bigger race pumps so just how much vacuum could one pull at 6000rpm? Most of the posts here have said they are limiting it to 10-12 inches.

If it's working for you that's great. I have no reason to change what I'm doing, it's worked for years and thousands of street miles. Honestly haven't seen any reason or any kind of data to pull tons of vacuum with it. You asked "why limit it" and I shared what I've been told, and it's working fine.

[slowbird]

Originally Posted by Formulajones

If it's working for you that's great. I have no reason to change what I'm doing, it's worked for years and thousands of street miles. Honestly haven't seen any reason or any kind of data to pull tons of vacuum with it.

I'm not looking to pull that much especially with the the GP being mostly street, just wondering how much people have seen the GZ pumps pull and if one really needs to worry about it. If it only pulls a max of 13-15 then why worry about it? I don't know enough about the GZ pumps to know their potential that's what I'm asking. It does appear to be the go to pump for most of the guys here running them on street cars though.

[Formulajones]

I went out to look, his pump has "Aerospace Components" machined on the housing. I don't know if that's the name brand or what. But it's been a great pump.

I agree if you are seeing 13-14 inches, I probably wouldn't worry about a couple inches of vacuum. I just put a valve on it so I could dial his down a bit. I don't even remember how high it was, that was a few years ago.

The biggest reason he wanted to install one was after talking to Tony about the advantages, was the HP gain that could be had and dad was at the time on a HP quest. They promote good ring seal and even though the engine ran fine without one, Tony said it wouldn't hurt to have one. I don't know how much vacuum you really need to reach a good ring seal. I'd have to guess it would depend on the ring package the engine is built with. I don't believe Tony set this engine up with some super light tension ring package anyway, since this was primarily built as a street engine and not one of his all out race deals.

[procharged 79]

Why are you considering a vacuum pump? If you are NA, why not run a PCV set up? Now if you're running boost, I can see the need, but for a NA street car, not so much.

[Formulajones]

There are a bunch of NA street engines running around with a vacuum pump. Partly for the reasons I put in my post above.

PCV's work well at light throttle and cruise, not so much at WOT. That's where a vacuum pump is beneficial.

[procharged 79]

Originally Posted by Formulajones

There are a bunch of NA street engines running around with a vacuum pump. Partly for the reasons I put in my post above.

PCV's work well at light throttle and cruise, not so much at WOT. That's where a vacuum pump is beneficial.

And how often are you at WOT in your street car? I too have a Moroso 4 vane vacuum pump on one of my blown "street cars". I also have a PCV system on a NA street car. If you're driving it on the street, your at WOT 10% of the time, if that long. The other 90% you're in the idle, cruise, part throttle condition. Hardly the environment requiring the vac pump on a NA motor.

[Formulajones]

Apparently more than you realize. We aren't pussy footers

It's not about the environment anyway, the point is, a vacuum pump works at WOT and a PCV doesn't. Doesn't really matter how much WOT driving you do.

[procharged 79]

I'm not here to get into a pissing contest. Vacuum pumps have their place. Having run both set-ups, I can vouch as to their appropriateness in a street motor. Vac pumps were originally developed in drag racing for extremely high RPM engines with super thin, lightweight, low tension rings to keep the rings seated in the bottom of the ring land and prevent ring flutter at the extreme high RPM that these engines operate in, we're talking comp eliminator, pro stock type of stuff. Hardly street motor territory. Now these teams rely mostly on dry sump oiling for crankcase vacuum and may supplement with an electric vac pump. Tony knows his ****, now if he recommends a vac pump, then I'd use one, but I'd be hard pressed to believe he'd recommend one for a NA street motor.

Personally, I think vac pumps are where pro racing chick meets street car. As I said earlier, if you're running boost with a pressurized intake, I'll concede, a vac pump would be appropriate, but on a street car that sees WOT occasionally, and probably a max RPM range of 5500-7000, its a complete waste of money.

Bottom line, go ahead and spend the $750 for a vac set up. Or spend less than $200 on a super nice adjustable Wagner PCV valve set up that won't require any maintenance and live perfectly fine on the street.

[slowbird]

Originally Posted by procharged 79

I'm not here to get into a pissing contest. Vacuum pumps have their place. Having run both set-ups, I can vouch as to their appropriateness in a street motor. Vac pumps were originally developed in drag racing for extremely high RPM engines with super thin, lightweight, low tension rings to keep the rings seated in the bottom of the ring land and prevent ring flutter at the extreme high RPM that these engines operate in, we're talking comp eliminator, pro stock type of stuff. Hardly street motor territory. Now these teams rely mostly on dry sump oiling for crankcase vacuum and may supplement with an electric vac pump. Tony knows his ****, now if he recommends a vac pump, then I'd use one, but I'd be hard pressed to believe he'd recommend one for a NA street motor.

Personally, I think vac pumps are where pro racing chick meets street car. As I said earlier, if you're running boost with a pressurized intake, I'll concede, a vac pump would be appropriate, but on a street car that sees WOT occasionally, and probably a max RPM range of 5500-7000, its a complete waste of money.

Bottom line, go ahead and spend the $750 for a vac set up. Or spend less than $200 on a super nice adjustable Wagner PCV valve set up that won't require any maintenance and live perfectly fine on the street.

Thank for your concern on how I spend my money. But your post have nothing to do with the questions I asked.
Do you know how much a GZ pump will pull unrestricted?

[Formulajones]

Who's pissin?? I don't care what you want to use, I'm just commenting on what slowbird wanted to know and the why. Do as you wish, it's your car.

[GOAT8U2]

If you're not into the big pump off your front you can probably pull off what I'm doing.....

I'm working on taking a GM smog pump and swapping in a stronger electric motor and not having the giant belt driven system hanging off the front. It'll run via the Holley and hoping to hit 8-12" at power on. It'll pull on the pcv 10an fitting through a catch can and at that level of vacuum it appears to be worth about 3% in power.

[Formulajones]

Originally Posted by slowbird

Do you know how much a GZ pump will pull unrestricted?

That may have a lot to do with how you pulley it as I mentioned. I'm not familiar with the GZ pump or if it comes with various sized pulleys.

When I installed the Aerospace Components vacuum pump, it had 2 or 3 different sized pulleys, so you could tailor how fast you want to run it. I had it as slow as it would go and still put a regulator on it just to get it around 12 inches or so.

I did read some on the GZ site and they claim they are sealed up well, so I'd imagine it's going to pull pretty good. I thought it was interesting how they went on to claim how quiet it is with no click click noises. Thought that was funny, I've never heard the Aerospace Component pump make any noise at all, it's quiet as if it's not even there. Wasn't even aware that was a concern lol

[Scott Stoneburg]

I have a GZ on my car, the highest I have seen is near 15". I have it regulated to 7-10" of vacuum. The big advantage to me was sealing up the small oil leaks around the valley pan as much as any HP increase that comes with it. Mine is a street car, I have checked it a few times after driving and racing, never more than maybe a teaspoon of oil in the can.

[chuckies76ta]

Originally Posted by slowbird

I'm considering putting a vacuum pump on my GrandPrix, was looking at the GZ pumps from Butler. Read a decent amount of comments on here about them.
My question is anyone run one without a bypass to set vacuum? I'm curious just how much vacuum they can pull and why limit it?

I run 2 of the GZ pumps. The smaller one on my engine, and the larger one on the wife's IA2 engine. They claim they will pull higher vacuum but I've never seen it. The smaller vacuum pump from GZ would only pull like 4 inch of vacuum on the IA2. Maybe the wipers inside the pump are worn out some. I don't know. I ordered the larger pump and it only pulls like 7 or 8 inches of vacuum. No leaks on both engines to date. It doesn't take much vacuum to keep these engines happy in my opinion. 4 or 5 inches of vacuum is all that is required. Now, for your question, I've never tried without the relief to see what they will actually do at wot. I set them initially with my vacuum gauge on the street with a few wot hits and they were around 7 or 8 inches of vacuum as I can remember. Haven't touched them since.

As far as limiting the vacuum amount, I to went of the old wives tale about the wrist pins. I've never had any luck with a pcv system on the street with my engine. Always was pushing the oil dipstick out of the tube and leaking oil. My engine has no oil leaks since installing the pump like 5 years ago. Another benefit is the condensation it removes. I drain the catch can on these engines ever so often with maybe a teaspoon of water oil mix. The other thing I'll do every so often, is open the suction tube and squirt a little engine oil in the tube just to lubricate the vanes in the pump a bit more.

[procharged 79]

Originally Posted by slowbird

Thank for your concern on how I spend my money. But your post have nothing to do with the questions I asked.
Do you know how much a GZ pump will pull unrestricted?

Pick up the phone and call GZ.

[Formulajones]

That's another nice benefit that was mentioned but hardly ever talked about. These pumps are great at removing the moisture and impurities from the crankcase, keeping the oil cleaner.