LS1 Glowing Headers with VCM710 - Too much timing?
Thread Starter
On The Tree
Joined: Feb 2015
Posts: 145
Likes: 11
From: Brisbane, Australia
LS1 Glowing Headers with VCM710 - Too much timing? Hi All,
I've been chasing down issues with my motor with vacuum leaks, electrical gremlins and the rest and have these all sorted but now have 2 issues remaining:
1. The engine will idle ok, but as soon as I touch the accelerator it will then rev up to 2500-3000rpm and either stay there after releasing the pedal, or hangs for 3-5 seconds before slowly coming back down(ish).
2. When the car gets to temp and goes into closed loop the car won't idle under 1100rpm and then my headers get a nice red glow to them.
Is someone able to take a look at the tune file i posted and tell me if the idle timing is too high for a VCM710 cam:
Duration 232/234 Lobe Separation @ 110 Valve Inlet .590" Exhaust .596"
Coolant temp jumped to 101 within 3 minutes if running.
The tune is set up for speed density, motor is stock bottom end, ported 241 heads, 102mm throttle body and sniper EFI clone intake
Here's the shiny glow video, from about 1:30 you'll see if it kick into closed loop and shine:
This motor is slowly driving me insane, so any help is greatly appreciated
I've been chasing down issues with my motor with vacuum leaks, electrical gremlins and the rest and have these all sorted but now have 2 issues remaining:
1. The engine will idle ok, but as soon as I touch the accelerator it will then rev up to 2500-3000rpm and either stay there after releasing the pedal, or hangs for 3-5 seconds before slowly coming back down(ish).
2. When the car gets to temp and goes into closed loop the car won't idle under 1100rpm and then my headers get a nice red glow to them.
Is someone able to take a look at the tune file i posted and tell me if the idle timing is too high for a VCM710 cam:
Duration 232/234 Lobe Separation @ 110 Valve Inlet .590" Exhaust .596"
Coolant temp jumped to 101 within 3 minutes if running.
The tune is set up for speed density, motor is stock bottom end, ported 241 heads, 102mm throttle body and sniper EFI clone intake
Here's the shiny glow video, from about 1:30 you'll see if it kick into closed loop and shine:
This motor is slowly driving me insane, so any help is greatly appreciated
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Joined: Jul 2018
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From: Missouri
You need a local tunner to get it strapped down on a dyno and get it straightened out. I'm guessing it's lean, and tune is whack or fuel system isn't up to par or perhaps a touch of both... I've had that same cam (TSP 232/234 .600/.600 110) and it took some time to get dialed in , it has a good amount of overlap also drilled out air hole on throttle body. But after a couple good tunning sessions it was awesome. Really snappy and carried power very well mid to high end.
Thread Starter
On The Tree
Joined: Feb 2015
Posts: 145
Likes: 11
From: Brisbane, Australia
You need a local tunner to get it strapped down on a dyno and get it straightened out. I'm guessing it's lean, and tune is whack or fuel system isn't up to par or perhaps a touch of both... I've had that same cam (TSP 232/234 .600/.600 110) and it took some time to get dialed in , it has a good amount of overlap also drilled out air hole on throttle body. But after a couple good tunning sessions it was awesome. Really snappy and carried power very well mid to high end.
Fuel system is definitely up to par, 425lph in tank with 8an lines all the way to the front, not running vacuum adjustment.
Unfortunately all the tuners that deal with LS1s are booked out for the next month and I have a car event I want to take the car to before then, to at least park it there.
Any chance you can send me your tune and I can copy and paste some tables into mine.
I have the 3.5mm hole drilled in the throttle body also.
Thread Starter
On The Tree
Joined: Feb 2015
Posts: 145
Likes: 11
From: Brisbane, Australia
Doesn't hurt to ask.
I have a mate's PCM that had a same spec cam and similar setup minus the ported heads that I might give a go.
It was tunerlocked and on EFI live instead of HPTuners but I managed to use a hack to nypass that and download the BIN anyway so if it's close I can sit there on the computer for a few hours and copy and paste all of the tables across into my tune file.
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Thread Starter
On The Tree
Joined: Feb 2015
Posts: 145
Likes: 11
From: Brisbane, Australia
So the symptoms are fixed (i.e. no more glowing headers) with the replacement of the 102mm throttle body minus the hole drilled in the blade.
I took the car for a drive yesterday and idle was good, no stalling, but it did feel like a pig, no power whatsoever and almost like flaring, so I suspect the issue is still timing, but it'll probably need to go to a tuner to sort that out.
I took the car for a drive yesterday and idle was good, no stalling, but it did feel like a pig, no power whatsoever and almost like flaring, so I suspect the issue is still timing, but it'll probably need to go to a tuner to sort that out.
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So the symptoms are fixed (i.e. no more glowing headers) with the replacement of the 102mm throttle body minus the hole drilled in the blade.
I took the car for a drive yesterday and idle was good, no stalling, but it did feel like a pig, no power whatsoever and almost like flaring, so I suspect the issue is still timing, but it'll probably need to go to a tuner to sort that out.
I took the car for a drive yesterday and idle was good, no stalling, but it did feel like a pig, no power whatsoever and almost like flaring, so I suspect the issue is still timing, but it'll probably need to go to a tuner to sort that out.
Thread Starter
On The Tree
Joined: Feb 2015
Posts: 145
Likes: 11
From: Brisbane, Australia
I already said I have HPTuners, and the problem was the throttle body.
Once the hole was gone my tuner had it sorted over email in 3 flashes after I posted the logs.
Thanks all for the help.