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I wouldn't do it just for track. But then again, if you're gonna change the fuel for the track, then the tune is gonna change anyway.
Yeah I mean throwing the belt on is no biggie. I am more fighting if it's worth any hp for the money. I'd hate to spend a grand or more on it and get absolutely nothing but more work from it. Maybe i can borrow yours when you decide to pull your car apart again??
Well what I am saying is the tune is going to be affect taking that thing on and off. When I first put the pump on mine and we had it on the dyno, Brian was asking me if fuel pressure was dropping off because the thing was wanting a decent bit more fuel. Now some peoples experiences have been different. @jayyyw and Nate had mehh experiences with theirs and didn't see much performance gain. Not sure if this is due to the dry sump. Ben I believe hasn't had issues with it on his car though.
Well what I am saying is the tune is going to be affect taking that thing on and off. When I first put the pump on mine and we had it on the dyno, Brian was asking me if fuel pressure was dropping off because the thing was wanting a decent bit more fuel. Now some peoples experiences have been different. @jayyyw and Nate had mehh experiences with theirs and didn't see much performance gain. Not sure if this is due to the dry sump. Ben I believe hasn't had issues with it on his car though.
Having a different tune is the least of my worries. Laptop is always in the car and flashing takes a few minutes, i managed my nitrous tunes that way, didn't mind it.
Having a different tune is the least of my worries. Laptop is always in the car and flashing takes a few minutes, i managed my nitrous tunes that way, didn't mind it.
That is what I am saying. If you plan on switching tunes for fuel then it wouldn't be a big deal then. For ease of it, I would just do a -12 hose from each cover to their own cans. Or I have always wanted to try the header evac route. That seems to work very well.
That is what I am saying. If you plan on switching tunes for fuel then it wouldn't be a big deal then. For ease of it, I would just do a -12 hose from each cover to their own cans. Or I have always wanted to try the header evac route. That seems to work very well.
Funny you mention the header evac.. always wanted/preferred to do it that way. just didn't even think about those until after i put the headers in and you need to weld in the connection tubes. best route seems to be go with dual cans for now and then route to the headers whenever i can justify yanking the headers all the way out again.
Funny you mention the header evac.. always wanted/preferred to do it that way. just didn't even think about those until after i put the headers in and you need to weld in the connection tubes. best route seems to be go with dual cans for now and then route to the headers whenever i can justify yanking the headers all the way out again.
I don't know if you would really need the headers out... Most of the companies that make those bungs suggest after the collector for placement.
NVM, just looked at your one picture.. If you did it on the headers themselves after the collector, then they would definitely need to come off. Not sure if putting them in the x pipe would work well.
A vacuum pump has benefits, but only if you can get it to not throw up oil after every drive/hit. Ultimately, I ended up just plumbing the outlet back into the dry sump tank and then venting the tank to a catch can. I pretty much did oil changes frequently, so I wasn't really worried about anything happening to the oil/motor.
The only before and after data I got was when I put the pump on my first Z06. It lost ~6hp on the dyno (not same day) but felt WAY stronger on the street. Opposite to Mike, we had to pull fuel out of the tune for the vacuum pump. Engine was able to rev easier, so less load on the engine. Saw HUGE gains on nitrous. Same shot picked up ~60hp.
If you are trying to get every ounce of performance out of the car, a vacuum pump is a no brainer.
John and I both have summit (total seal) gas ported rings in my and his last motor combo. Mine are 043, 043, 3.0mm. I think John ran the same.
Stock LS7 is .047.047 2mm, so it’s got a decent ring pack stock. Gas ported rings help. .040 top and second is as thin as i’d run on the street. Race builds are getting down to .026 these days.
Is there a percentage increase in power that the thinner ring pack and gas porting equates to for a streetable driven car that gets pounded on?
Not sure on an exact percentage.. But thinner rings are going to cause less rotational friction. I've seen some claim gains similar to adding a full point of compression. But I am not sure what the original thickness to new thickness was on those gains.
Is there a percentage increase in power that the thinner ring pack and gas porting equates to for a streetable driven car that gets pounded on?
I had that data…from early 90’s…LOL
It’s definitely real power, as ring friction is the enemy of an engine regardless of the oiling system being up to par. In a street driven car, that sees 95% low load and low rpm it’s minimal. In a race application that sees 98% WOT and constant high rpm, the percentage goes way up obviously. And of course a light tension, thin ring pack that is designed to ease frictional losses needs the help of a vac pump…or a high end dry sump pump, which actually will produce more crankcase vacuum than the vac pump at rpm…to help with ring seal. Gas ported pistons and rings help a ton here also.
A vacuum pump has benefits, but only if you can get it to not throw up oil after every drive/hit. Ultimately, I ended up just plumbing the outlet back into the dry sump tank and then venting the tank to a catch can. I pretty much did oil changes frequently, so I wasn't really worried about anything happening to the oil/motor.
The only before and after data I got was when I put the pump on my first Z06. It lost ~6hp on the dyno (not same day) but felt WAY stronger on the street. Opposite to Mike, we had to pull fuel out of the tune for the vacuum pump. Engine was able to rev easier, so less load on the engine. Saw HUGE gains on nitrous. Same shot picked up ~60hp.
If you are trying to get every ounce of performance out of the car, a vacuum pump is a no brainer.
After seeing you and a few others saying they were prone to filling cans on the street, I figured the only way to do it reasonably was to drain back to the tank and do frequent oil changes, which i already do. but that is also what made think the header evac kit would keep things simple and still be effective.
You routed pump outlet back to the fill cap? and what i haven't spent much time on is the 2 other connections at the dry sump tank. Cap the oem valve cover connections and the rear-most tank connection on the tank? Run the forward sump tank connection to a catch can? I know we shouldn't cap the tank vent, just haven't figured out where that should go when a vac pump is involved.
( and for the other comments, the car is still SBE)
You guys are making me consider spending money again!!
Last edited by Ryans99ls1; Mar 20, 2025 at 01:38 PM.
After seeing you and a few others saying they were prone to filling cans on the street, I figured the only way to do it reasonably was to drain back to the tank and do frequent oil changes, which i already do. but that is also what made think the header evac kit would keep things simple and still be effective.
You routed pump outlet back to the fill cap? and what i haven't spent much time on is the 2 other connections at the dry sump tank. Cap the oem valve cover connections and the rear-most tank connection on the tank? Run the forward sump tank connection to a catch can? I know we shouldn't cap the tank vent, just haven't figured out where that should go when a vac pump is involved.
( and for the other comments, the car is still SBE)
You guys are making me consider spending money again!!
Yeah, I routed it back to the fill cap. I bought a 12an oil cap. You do have to cut the hood in that area for the fitting, just be aware. I ran both connections off the top of the tank to a vented catch can. Make sure the motor is sealed up well, so yes, cap any connections that don't go to the vacuum pump.
Here’s what I’m running, this is a catch can that has coolant ports to heat it up and stop condensation from forming and then routes the oil back to your pan.
Here’s what I’m running, this is a catch can that has coolant ports to heat it up and stop condensation from forming and then routes the oil back to your pan.
if there are no coolant ports the hot oil and gasses will for condensation and that will cause issues if it goes back into your pan.
If this was a car i was street driving a lot, i would go this route. Nice piece. But the oil gets changed really often, after every track outing with some street hits mixed in which would be 10-15 passes and not even 200 miles. Plus, if i start playing with fuel mixtures, the oil changes will increase.
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