LS6 Intake - getting closer
#42
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Another update
Finished the DOD connector, here's a couple of pics with the lifter cover fully assembled:
Hmmm, need to replace the stock bolts with something a bit lower profile, I need to find something like the button top bolts that come with the FAST 90
Here's a bottom view that shows how the DOD connector plugs in:
And just for the hell of it, here's a shot of the bottom of the valley cover that provides a bit of detail of the DOD solenoids:
Finished the DOD connector, here's a couple of pics with the lifter cover fully assembled:
Hmmm, need to replace the stock bolts with something a bit lower profile, I need to find something like the button top bolts that come with the FAST 90
Here's a bottom view that shows how the DOD connector plugs in:
And just for the hell of it, here's a shot of the bottom of the valley cover that provides a bit of detail of the DOD solenoids:
#44
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Just a bump.
Haven't worked on this or any of my other mods for a few months (boxes of parts are just gathering dust in the garage). I'm about 95% there on the intake, just have to figure out how to hook up the brake booster and MAP since I had to eliminate the fittings on the rear of the LS6 intake in order to clear the power steering resevoir.
Trying to decide if that can be relocated to the top of the intake like on the LS4.
Haven't worked on this or any of my other mods for a few months (boxes of parts are just gathering dust in the garage). I'm about 95% there on the intake, just have to figure out how to hook up the brake booster and MAP since I had to eliminate the fittings on the rear of the LS6 intake in order to clear the power steering resevoir.
Trying to decide if that can be relocated to the top of the intake like on the LS4.
#46
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I'm just about to get back to this project.
Spent some time a week or so ago replacing valve stem seals, valve springs, push rods and installiing 1.8 rocker arms...what a frigging pain in the *** that was on a FWD V8
At any rate, I've got a bit of tweaking to do to my tune, then I'll take it to a dyno for a baseline run.
Valley cover and intake manifold mods/adapter are all done and ready to go, so after the first visit to the dyno I'll do the swap, play with the tune some more and head back to the dyno to see what the difference is.
Work's kind of nuts at this time of year, so realistically there won't be any results to report until late September.
Spent some time a week or so ago replacing valve stem seals, valve springs, push rods and installiing 1.8 rocker arms...what a frigging pain in the *** that was on a FWD V8
At any rate, I've got a bit of tweaking to do to my tune, then I'll take it to a dyno for a baseline run.
Valley cover and intake manifold mods/adapter are all done and ready to go, so after the first visit to the dyno I'll do the swap, play with the tune some more and head back to the dyno to see what the difference is.
Work's kind of nuts at this time of year, so realistically there won't be any results to report until late September.
#54
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Somewhere earlier in this thread, I have pictures of the rear of the intake, I've shaved off the area where the MAP sensor would mount and have sealed off the area with a metal plate mounted on each side of the resulting hole, three bolts/nuts and generous amounts of RTV sealant between the plates. I have to order new seals for the intake runners since the ones that came with this unit look a bit rough.
I finally have my tune where I want it after installing the magnaflow, springs and rockers. The car's pulling consistent 0-60's of 5.5 seconds even on cold roads with all season tires (based on data logged using HPT). If I could ever get first gear traction, I'm sure 0-60's would be down to at least 5.3 seconds.
With the Comp 918 springs, I've bumped the first gear shift point to 6250 rpm (88 kmh or 55 mph), and am considering 6500, but I'm not sure what the DOD lifters can take (at 6500, that should be 96 kmh or 60 mph). Anyone bumped redline that far yet? I'm not sure that there's any point in bumping the redline any further until some airflow issues are resolved:
Data logs show that the stock intake system is causing some significant restrictions above ~5300 rpm. At my altitude, absolute atmospheric pressure almost never exceeds 93 kpa (compared to average sea level pressure of 101), I'm seeing MAP decreasing to 87 or 88 kpa at 6250 rpm, so intake restrictions are decreasing potential airflow by ~5.4 to 6.5% at the top end. If you look at the location of the MAP sensor, which is between the throttle body and the maniflod neck restriction, the measured restriction appears to be due to the stock airbox/intake tube (i have a K&N drop-in rather than a full CAI).
The question that remains unanswered is how much the manifold neck further restricts airflow. I suppose you could run a second MAP off the vacuum port located at the top of the manifold and see what pressure is present there. Maybe I should do that just to see if you can measure a pressure difference before and after the manifold neck.
#57
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The thing is, tool wise all you need is a dremel/die grinder, drill press and a few bits to do this (and someone who can weld aluminum). The only part that is really fiddly is rebuilding the DOD connector.
If I was to do it again, I'd probably go with a LS2 valley cover, reposition the OPSU mount and add on a Fast 90 and LS2 TB. There's just a few wiring changes between the LS2 and LS4 TB's, and I've seen a LS7 valley cover modified to allow a 90mm TB to be mounted in this orientation.
I am willing to post up a 1:1 dimensioned drawing of the TB adapter for anyone who wants to give it a shot. The template is easy enough to make - I made my template by tracing the manifold flange and TB flange on different pieces of paper and then just overlaying one over the other with enough rotation to allow the electrical connector to clear the manifold flange.