Anyone running a vacuum reservoir for brakes on a cammed car? - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

InFiD3ViL · 05-02-2020, 03:43 PM

I completed my cam install last month and am generally very happy with it. Ryan from GPI did an amazing job with the tune and the power feels great. Lopey as hell for a stage 1 cam.

Obviously there are some trade offs though when coming from a stock cam. For me, that trade off is braking. I was totally aware that with a stock convertor the cam would try to push through the brakes, which it does. But my problem seems to be more vacuum related. When I cold start my car I have to let it warm up and build vacuum until it is into closed loop. Otherwise I have nearly no brakes, especially because at open loop (cold start) rpms it is pushing like a mofo, and I lose some pedal. This only started after I installed the cam, no known braking issues, clean fluid, suspected good booster, no leaks.

So I was thinking about installing a vacuum reservoir to have some vacuum on reserve for braking or emergency situations. I know I only have a stage one cam, but it's not tiny. I have the LS3 version of the SS1 cam from GPI @ .646/.637, (224/237, 112 +4), while for comparisons, the L99 SS1 VVT version is .637/.637, (219/231, 112 +6). The reason I bring that up is because those VVT cams were engineered and expected to be installed with an auto trans from the drawing board. While the LS3 cam was likely expected to be installed in a manual car in most cases, or at least in one with an aftermarket stall. I hope that makes sense. Maybe I am overthinking this.

Am I barking up the wrong tree here? Can this be addressed in my tune with idle changes or is it just what is to be expected to have some vacuum loss with a cam and stock convertor? Can anyone with experience please hook a brother up with some knowledge?

I found this:

https://www.amazon.com/dp/B071J1JW7N...v_ov_lig_dp_it

or I can go cheaper with this and buy a gauge for it:

https://www.amazon.com/Mr-Gasket-370...s%2C171&sr=8-1

pnwdan · 05-02-2020, 03:49 PM

I have a TSP stage 3 and have zero vacuum issues. The NPP even works with the residual vacuum when the car is off.

InFiD3ViL · 05-02-2020, 03:51 PM

Quote:

Originally Posted by pnwdan

I have a TSP stage 3 and have zero vacuum issues. The NPP even works with the residual vacuum when the car is off.

The smaller cams are a minority here, so I am expecting most to agree with you. Maybe I need to look into possible booster issues.

It's just weird because once the engine is warm and at normal idle I have no issues, aside from the convertor push. It is only when its idling over 1k rpm at cold start. If I try and jump in cold start and go somewhere, I'm not stopping. I rarely do that anyway, but still it makes me nervous of the potential for issues in traffic.

Stubbsy · 05-02-2020, 04:53 PM

Quote:

Originally Posted by InFiD3ViL

I completed my cam install last month and am generally very happy with it. Ryan did an amazing job with the tune and the power feels great. Lopey as hell for a stage 1 cam.

Obviously there are some trade offs though when coming from a stock cam. For me, that trade off is braking. I was totally aware that with a stock convertor the cam would try to push through the brakes, which it does. But my problem seems to be more vacuum related. When I cold start my car I have to let it warm up and build vacuum until it is into closed loop. Otherwise I have nearly no brakes, especially because at open loop (cold start) rpms it is pushing like a mofo, and I lose some pedal. This only started after I installed the cam, no known braking issues, clean fluid, suspected good booster, no leaks.

So I was thinking about installing a vacuum reservoir to have some vacuum on reserve for braking or emergency situations. I know I only have a stage one cam, but it's not tiny. I have the LS3 version of the SS1 cam from GPI @ .646/.637, (224/237, 112 +4), while for comparisons, the L99 SS1 VVT version is .637/.637, (219/231, 112 +6). The reason I bring that up is because those VVT cams were engineered and expected to be installed with an auto trans from the drawing board. While the LS3 cam was likely expected to be installed in a manual car in most cases, or at least in one with an aftermarket stall. I hope that makes sense. Maybe I am overthinking this.

Am I barking up the wrong tree here? Can this be addressed in my tune with idle changes or is it just what is to be expected to have some vacuum loss with a cam and stock convertor? Can anyone with experience please hook a brother up with some knowledge?

I found this:

https://www.amazon.com/dp/B071J1JW7N...v_ov_lig_dp_it

or I can go cheaper with this and buy a gauge for it:

https://www.amazon.com/Mr-Gasket-370...s%2C171&sr=8-1

I have exactly the same problem, LS3 conversion with cam and ported heads and supercharger. I just let it warm up for a couple of minutes as it’s a weekend only toy, I have thought about a stall converter.

Greenhornet2 · 05-02-2020, 05:01 PM

I really hate this "stage" cam crap it means nothing lol. That's a pretty big cam you have a decent bit more lift than i do. Duration about the same 112lsa with no advance. I haven't noticed any brake issue. I'm an ls3 tho.

anthony.martinez · 05-02-2020, 05:30 PM

Agreed with the "stage" scenario it is to me subjective. I have had many larger cammed rides. The biggest being I ran on the street was a .727/.716 with a 272/282 duration at .050 I had a little less vacuum than a regular cam but it was very manageable. My car the 2010 has the f35 cam in it now and absolutely zero brake issues. I also ran a G6X3 with no issues.

InFiD3ViL · 05-02-2020, 06:34 PM

I agree completely on the 'Stage' thing. I guess it helps vendors that sell more than one cam to differentiate their cams rather than giving them names.

Not sure how much this plays in, but at idle I am getting 10.3 inches of manifold vacuum.

1JEWLDSSRS · 05-02-2020, 07:04 PM

Quote:

Originally Posted by InFiD3ViL

I agree completely on the 'Stage' thing. I guess it helps vendors that sell more than one cam to differentiate their cams rather than giving them names.

Not sure how much this plays in, but at idle I am getting 10.3 inches of manifold vacuum.

I have the TSP 231/246 cam @ 112 LSA and I just went and cold started her up and my Aeroforce gauge is showing fluctuating 10.3 to 10.9, back and forth and I also have never had any brake issues. Good luck.

InFiD3ViL · 05-02-2020, 09:01 PM

Looking online I see this does affect a decent amount of cammed cars, but it mostly seems like older cars, not so much modern stuff. I am trying to find out what is differentiating between those with issues and without. But in order to do that it really would make sense for me to make sure my brake booster and brake system is mechanically sound first and that I have no vacuum leaks.

Either way, from what I am reading, the vacuum reservoirs seem to help quite a bit.

Greenhornet2 · 05-02-2020, 09:22 PM

You know i haven't looked at the brake booster system on these really. Usually they have a check valve in the large vacuum hose. Check that out maybe.

PhantomBlack · 05-02-2020, 09:45 PM

My car does the same thing on a cold start. It's been like that since I got my ss1 installed at gpi. Give it a few minutes and the brakes are back to normal. Haven't concerned me at all really.... Except if my car is at a shop.

InFiD3ViL · 05-02-2020, 10:36 PM

Quote:

Originally Posted by Stubbsy

I have exactly the same problem, LS3 conversion with cam and ported heads and supercharger. I just let it warm up for a couple of minutes as it’s a weekend only toy, I have thought about a stall converter.

Quote:

Originally Posted by PhantomBlack

My car does the same thing on a cold start. It's been like that since I got my ss1 installed at gpi. Give it a few minutes and the brakes are back to normal. Haven't concerned me at all really.... Except if my car is at a shop.

Ok, that makes me feel a little bit better, thanks guys. I wonder what causes it on the cold start.

christianchevell · 05-03-2020, 09:19 AM

I would suggest if you don't have one get one as far as a separate reservoir for the clutch though for guys with a m-6 to help keep the fluid clean they can be had from a Holden on diygen5.com, You just have to deal with no reservoir for vacuum which never bothered me with large cam m-6 and ceramics of course being cold are not going to grip as much as a organic or semi metallic..... IMO good Luck!

And just let it warm up a little it will even spill heat over to the brakes......that yup with lots of duration on a cam etc will not be what they used to be but should still work well...…...

Bo White · 05-03-2020, 09:58 PM

I'm running a TSP 243/255-111 with 27* overlap. With the 102mm TB I have just enough vacuum to operate the brakes. 5" of vacuum.
I put my ported stock TB on and it does just fine. 6" of vacuum.

05-02-2020, 03:43 PM	#1
InFiD3ViL Drives: 2010 CGM 2SS/RS LS3 Swapped A6 Join Date: Sep 2016 Location: Spring Hill, FL Posts: 4,737	Anyone running a vacuum reservoir for brakes on a cammed car? I completed my cam install last month and am generally very happy with it. Ryan from GPI did an amazing job with the tune and the power feels great. Lopey as hell for a stage 1 cam. Obviously there are some trade offs though when coming from a stock cam. For me, that trade off is braking. I was totally aware that with a stock convertor the cam would try to push through the brakes, which it does. But my problem seems to be more vacuum related. When I cold start my car I have to let it warm up and build vacuum until it is into closed loop. Otherwise I have nearly no brakes, especially because at open loop (cold start) rpms it is pushing like a mofo, and I lose some pedal. This only started after I installed the cam, no known braking issues, clean fluid, suspected good booster, no leaks. So I was thinking about installing a vacuum reservoir to have some vacuum on reserve for braking or emergency situations. I know I only have a stage one cam, but it's not tiny. I have the LS3 version of the SS1 cam from GPI @ .646/.637, (224/237, 112 +4), while for comparisons, the L99 SS1 VVT version is .637/.637, (219/231, 112 +6). The reason I bring that up is because those VVT cams were engineered and expected to be installed with an auto trans from the drawing board. While the LS3 cam was likely expected to be installed in a manual car in most cases, or at least in one with an aftermarket stall. I hope that makes sense. Maybe I am overthinking this. Am I barking up the wrong tree here? Can this be addressed in my tune with idle changes or is it just what is to be expected to have some vacuum loss with a cam and stock convertor? Can anyone with experience please hook a brother up with some knowledge? I found this: https://www.amazon.com/dp/B071J1JW7N...v_ov_lig_dp_it or I can go cheaper with this and buy a gauge for it: https://www.amazon.com/Mr-Gasket-370...s%2C171&sr=8-1 __________________ 2010 CGM Camaro 2SS LS3 Swapped A6 - GPI LS3 SS1 .647/.638, (224/237, 112 +4, 7º overlap) on CamMotion 8620 core, BTR Platinum .660" Dual Spring kit w/titanium retainers, CHE bronze trunnion upgrade, stock heads milled @ .015, Melling HV 10296 oil pump, TSP 1-7/8" long tube headers (W/Catless Off-road Pipes), Corsa Xtreme 3" Catback, GPI Ported/Rod Mod Intake, Stage 2 Ported Throttle Body, Vararam OTR CAI, Mike Norris Gen 2 catch can + GM 1LE clean side separator, 160º thermostat - Megan Racing adjustable coilovers (lowered 1.75"), MRR M017 10/11" wheels-Tuned by Ryan @ GPI Last edited by InFiD3ViL; 05-02-2020 at 10:39 PM.

05-02-2020, 03:49 PM	#2
pnwdan Drives: 2014 2SS/RS Join Date: Jan 2018 Location: Washington Posts: 848	I have a TSP stage 3 and have zero vacuum issues. The NPP even works with the residual vacuum when the car is off. __________________ 2014 2SS/RS LS3/M6

05-02-2020, 05:01 PM	#5
Greenhornet2 Drives: 2011 Camaro 2SS LS3 Whipple Join Date: May 2019 Location: Connecticut Posts: 1,925	I really hate this "stage" cam crap it means nothing lol. That's a pretty big cam you have a decent bit more lift than i do. Duration about the same 112lsa with no advance. I haven't noticed any brake issue. I'm an ls3 tho. __________________ Whipple 2.9 CAI ID1050x injectors ZL1 Pump JRE FPCM JMS Voltage booster JRE Rough Idle blower cam BTR .660 springs CHE trunnion kit 1 7/8 Speed Engineering Borla Atak JRE scoop 1.5" lowering springs BMR trailing arms and toe links Cradle inserts 704WHP 603WTQ 93 octane

05-02-2020, 06:34 PM	#7
InFiD3ViL Drives: 2010 CGM 2SS/RS LS3 Swapped A6 Join Date: Sep 2016 Location: Spring Hill, FL Posts: 4,737	I agree completely on the 'Stage' thing. I guess it helps vendors that sell more than one cam to differentiate their cams rather than giving them names. Not sure how much this plays in, but at idle I am getting 10.3 inches of manifold vacuum. __________________ 2010 CGM Camaro 2SS LS3 Swapped A6 - GPI LS3 SS1 .647/.638, (224/237, 112 +4, 7º overlap) on CamMotion 8620 core, BTR Platinum .660" Dual Spring kit w/titanium retainers, CHE bronze trunnion upgrade, stock heads milled @ .015, Melling HV 10296 oil pump, TSP 1-7/8" long tube headers (W/Catless Off-road Pipes), Corsa Xtreme 3" Catback, GPI Ported/Rod Mod Intake, Stage 2 Ported Throttle Body, Vararam OTR CAI, Mike Norris Gen 2 catch can + GM 1LE clean side separator, 160º thermostat - Megan Racing adjustable coilovers (lowered 1.75"), MRR M017 10/11" wheels-Tuned by Ryan @ GPI

05-02-2020, 09:01 PM	#9
InFiD3ViL Drives: 2010 CGM 2SS/RS LS3 Swapped A6 Join Date: Sep 2016 Location: Spring Hill, FL Posts: 4,737	Looking online I see this does affect a decent amount of cammed cars, but it mostly seems like older cars, not so much modern stuff. I am trying to find out what is differentiating between those with issues and without. But in order to do that it really would make sense for me to make sure my brake booster and brake system is mechanically sound first and that I have no vacuum leaks. Either way, from what I am reading, the vacuum reservoirs seem to help quite a bit. __________________ 2010 CGM Camaro 2SS LS3 Swapped A6 - GPI LS3 SS1 .647/.638, (224/237, 112 +4, 7º overlap) on CamMotion 8620 core, BTR Platinum .660" Dual Spring kit w/titanium retainers, CHE bronze trunnion upgrade, stock heads milled @ .015, Melling HV 10296 oil pump, TSP 1-7/8" long tube headers (W/Catless Off-road Pipes), Corsa Xtreme 3" Catback, GPI Ported/Rod Mod Intake, Stage 2 Ported Throttle Body, Vararam OTR CAI, Mike Norris Gen 2 catch can + GM 1LE clean side separator, 160º thermostat - Megan Racing adjustable coilovers (lowered 1.75"), MRR M017 10/11" wheels-Tuned by Ryan @ GPI

05-02-2020, 05:30 PM	#6
anthony.martinez Drives: 2010 Join Date: Dec 2018 Location: texas Posts: 119	Agreed with the "stage" scenario it is to me subjective. I have had many larger cammed rides. The biggest being I ran on the street was a .727/.716 with a 272/282 duration at .050 I had a little less vacuum than a regular cam but it was very manageable. My car the 2010 has the f35 cam in it now and absolutely zero brake issues. I also ran a G6X3 with no issues.

05-02-2020, 09:22 PM	#10
Greenhornet2 Drives: 2011 Camaro 2SS LS3 Whipple Join Date: May 2019 Location: Connecticut Posts: 1,925	You know i haven't looked at the brake booster system on these really. Usually they have a check valve in the large vacuum hose. Check that out maybe. __________________ Whipple 2.9 CAI ID1050x injectors ZL1 Pump JRE FPCM JMS Voltage booster JRE Rough Idle blower cam BTR .660 springs CHE trunnion kit 1 7/8 Speed Engineering Borla Atak JRE scoop 1.5" lowering springs BMR trailing arms and toe links Cradle inserts 704WHP 603WTQ 93 octane

05-02-2020, 09:45 PM	#11
PhantomBlack Drives: 2014 Camaro 2SS Join Date: Oct 2017 Location: Brooksville, FL Posts: 197	My car does the same thing on a cold start. It's been like that since I got my ss1 installed at gpi. Give it a few minutes and the brakes are back to normal. Haven't concerned me at all really.... Except if my car is at a shop.

05-03-2020, 09:19 AM	#13
christianchevell old school chevy rodder Drives: 2021 zl1 a-10 WildCherry Join Date: Jul 2012 Location: Oregon Posts: 5,622 View My Garage	I would suggest if you don't have one get one as far as a separate reservoir for the clutch though for guys with a m-6 to help keep the fluid clean they can be had from a Holden on diygen5.com, You just have to deal with no reservoir for vacuum which never bothered me with large cam m-6 and ceramics of course being cold are not going to grip as much as a organic or semi metallic..... IMO good Luck! And just let it warm up a little it will even spill heat over to the brakes......that yup with lots of duration on a cam etc will not be what they used to be but should still work well...…... __________________ 2021 Wild Cherry ZL1 A10, Sunroof, Data,Red Carbon Interior, Nav, RotoFab Big Gulp , Elite x2ultra, Borla ATAK, Driveshaft shop, BMR susp, Speed covers, intercoolers, ATI , 2650 MAG, DSX lid, 103 NW, TSP Longtubes & cats, LPE, 1le mods, ,LME cover, Katech pump and chain, Trunnions, BTR stage 2, LPE boostapump, Gforce, Speed eng , Granetteli, etc etc

05-03-2020, 09:58 PM	#14
Bo White Drives: 2015 Summit White 2SS 1LE Join Date: Feb 2012 Location: Vance Alabama Posts: 8,095	I'm running a TSP 243/255-111 with 27* overlap. With the 102mm TB I have just enough vacuum to operate the brakes. 5" of vacuum. I put my ported stock TB on and it does just fine. 6" of vacuum.