Time to pull the covers and start drilling.
Too Much Vacuum??
Thread Starter
Instructor
Joined: Jan 2006
Posts: 214
Likes: 5
From: Middletown Delaware
Too Much Vacuum??
O.K. I have a 98 coupe. Let me start off by explaining what I installed.
Swapped out stock head for trickflow 215, 7.5 pushrods, harland rockers, SVO 30# injector, New rails and plumbing, Fast 90 w/ls2 ported tb. I also installed abear valve covers with catch can.
I was removing the oil cap with the car idling and I couldn't get the cap to come off, as I pulled harder air started too rush past cap. Put hand over opening and it is like putting your hand over the end of a shop vac hose (after holding it there for a few seconds).
Is this normal on a N/A LS1??
How much vacuum pressure is normal?
Car seems to run fine for not being tuned yet, but I am concerned about the amount of vacuum there is. Is this going to damage anything?? How would I even reduce it in a closed system like this??
Any input would be appreciated. Thanks.
Some pics of setup.
Swapped out stock head for trickflow 215, 7.5 pushrods, harland rockers, SVO 30# injector, New rails and plumbing, Fast 90 w/ls2 ported tb. I also installed abear valve covers with catch can.
I was removing the oil cap with the car idling and I couldn't get the cap to come off, as I pulled harder air started too rush past cap. Put hand over opening and it is like putting your hand over the end of a shop vac hose (after holding it there for a few seconds).
Is this normal on a N/A LS1??
How much vacuum pressure is normal?
Car seems to run fine for not being tuned yet, but I am concerned about the amount of vacuum there is. Is this going to damage anything?? How would I even reduce it in a closed system like this??
Any input would be appreciated. Thanks.
Some pics of setup.
Drifting
Joined: Mar 2005
Posts: 1,737
Likes: 0
From: Northern VA
Thread Starter
Instructor
Joined: Jan 2006
Posts: 214
Likes: 5
From: Middletown Delaware
Hi dumbass here.
When I added the LS2 tb it does not have a air feed for crank system, so I had on incoming air (hence my new nickname).
I tapped into the air bridge (after the MAF) too pull the fresh air in. It is not recommended to just put a breather on as that air has not been accounted for by the Pcm.
Thanks J
When I added the LS2 tb it does not have a air feed for crank system, so I had on incoming air (hence my new nickname).
I tapped into the air bridge (after the MAF) too pull the fresh air in. It is not recommended to just put a breather on as that air has not been accounted for by the Pcm.
Thanks J
Drifting
Joined: Mar 2005
Posts: 1,737
Likes: 0
From: Northern VA
Hi dumbass here.
When I added the LS2 tb it does not have a air feed for crank system, so I had on incoming air (hence my new nickname).
I tapped into the air bridge (after the MAF) too pull the fresh air in. It is not recommended to just put a breather on as that air has not been accounted for by the Pcm.
Thanks J
When I added the LS2 tb it does not have a air feed for crank system, so I had on incoming air (hence my new nickname).
I tapped into the air bridge (after the MAF) too pull the fresh air in. It is not recommended to just put a breather on as that air has not been accounted for by the Pcm.
Thanks J
Shouldn't matter how many vents you have.
Further, the PCM is gonna get tuned anyway.
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