TiredGXP

iTrader: (2)

OK, time for an update

Spent a few hours today working on an adapter for the TB.

In designing this thing I came across a couple of more issues that need to be dealt with:

1) Interference in the bolt holes for the TB to the adapter and the adapter to the LS6 intake.

2) Electrical connector to the TB will interfere with the standard flange on the LS6 intake.

My solution for both is to slightly rotate the TB in a counter-clockwise direction. Some additional trimming of the LS6 flange may be required.

First pic is using a hole saw in the drill press to cut the bore of the adapter


Layout of the rough template


Trial fit after hours of trimming/adjusting


Tomorrow: Drilling and tapping adapter to mount the TB, and adapter to the intake flange, and creating the groove for the seal ring.

I'd kill for a milling machine right about now

TiredGXP

iTrader: (2)

Time for another update.

I wasn't all that happy with the adapter in the post above, so since I had enough aluminum left over I built another, beefier adapter. Also found a better tool for boring the hole in the adapter plate, much smoother, more uniform hole.

Anyway, here's a pic of the TB mounted to the manifold. You can see the that the TB sits at a bit of an angle to provide some clearance for the electrical connector:


A shot of the TB connector. Dammit, didn't rotate the TB enough, so now I will have to remove a bit of material from the manifold flange


And a shot down the barrel of the TB (crappy quality on this one, too close)

BADDLS1SS

iTrader: (22)

Isnt there gonna be an air leak between the orange intake seal and your plate right by that connector? i cant remember if the orange o ring goes around the opening off hand.

TiredGXP

iTrader: (2)

This won't cause a vacuum leak. The bit of the seal that you see is a secondary "loop" in the seal, the area inside this area of the seal is just a "void" not connected to the plenum. There is a full seal around the throat of the intake.

The adapter does need to cover the right side near the top as that area is connected to the intake plenum. Crappy description; I think there's a pic in one of the earlier posts that shows what I'm talking about.

Edit: I guess I didn't post a pic of the intake flange, oh well.

fotoboy

iTrader: (1)

What are your expected hp increase from this mod?

TiredGXP

iTrader: (2)

Well, the LS6 makes about 15 hp more than the LS1 intake, so that's my base expectation. The primary advantage of the LS6 over the LS1 is the design of the intake runner. A lot depends on how the LS4's runners stack up against either of those manifolds. I haven't found anything that discusses the design differences.

Here's a couple of pics of the LS4 intake neck and the LS6 intake neck. Notice that the LS4 has a D-shaped restriction in the neck to clear the oil pressure sending unit, some rectangular thing projecting into the neck, and that the #7 cylinder intake runner also seems to interfere with airflow entering the manifold plenum. I'm just guessing here, but I expect that eliminating these restrictions will provide much better gains than the LS1 gets.

I'll do a dyno run after all mods are in to see what the total effect of my mods are. I suppose it would be nice to see the results after each mod, but I'm not really interested in paying for dyno time 5 times



Notice how the LS6 has none of those restrictions:



Second picture is a bit blurry (note to self, use macro setting on camera next time), but you can see the differences in the inlet. LS6 is a taller manifold with smaller diameter support pillars, definitely a different design on the runners.

Blk02Ls1A4

iTrader: (3)

very nice, keep the updates coming!

fotoboy

iTrader: (1)

I know on my vette it was very noticalbe gain going from the ls1 to the ls6, keep us updated!

TiredGXP

iTrader: (2)

Thanks for the interest, guys.

Except for some minor tweaks, the TB adapter is done. There won't be much to update for a while, its below freezing here and the garage only has a small electric space heater. It will have to be upgraded before I kick off my next project.

I need to do some measurements on the LS4 fuel rails to see if they'll fit the LS6 intake. As noted in a prior post, the LS6 is a taller manifold, so fitment is a concern until I verify the measurements.

I've found a shop that will TIG the oil pressure sending unit mount back together on the valley cover, so I'll get it done sometime in the next couple of weeks.

For now I'm just accumulating parts for the rest of my mods. Want to have everything in place and ready to go for the long weekend in May - I figure I need two days for the valve springs, rockers, and intake, another day to install the exhaust and do some basic tuning.

I have a good mix of highway and city driving on my 70 km round trip to/from work, so lots of data can be logged during the week to finish tuning.

jarcher

its good to see that the intake is working out for you

TiredGXP

iTrader: (2)

I guess it's time for a bit of an update on this project:

Got the valley cover back from the welder yesterday. Not the best looking welding bead I ever saw, but it did the job. A test fit shows that the bead does not interfere with the manifold.



Started to play around with the DOD connector today. Here's what is left after cutting the connector apart and removing sufficient plastic to expose the conductors. The plan is to solder about 5 inches of wire in between the two pieces so that I can move the plug end out from under the manifold.



Exposing the conductors required eliminating the bit of the connector that goes through, and seals to, the valley cover. I found a heater hose connector made out of the same type of plastic as the original connector that is just the right diameter to fit through the valley cover. After cutting off the bit I needed, It was possible to create a groove in the fitting for the o-ring used to seal the original connector.

In this next pic, the bit on the left is what I made up to seal the hole in the valley cover.



This next pic is the bits and pieces put back together. This will fit through the valley cover and plug into the DOD solenoids. I just have to solder the wires up and get some heat shrink.



Looks like I will have to get the LS6 fuel rail. It doesn't look like The LS4 fuel rail will fit over the taller manifold.

Also identified another potential clearance issue. The LS6 is designed for the MAP sensor and brake booster to hook up to a fitting that comes out the rear of the manifold, I think that this fitting is going to hit the power steering canister. That probably explains why the LS4 has the MAP sensor mounted on the intake neck and the extra vacuum fitting on the top of the LS4 manifold plenum.

Taz34SS

iTrader: (2)

have you thought about porting out the TB From the LS4? I am going to be looking at getting this done soon.

TiredGXP

iTrader: (2)

I've thought about it, but I have to admit that I haven't done any real research into it. What do you figure the potential gain is from having this done?

Mgpeagle

iTrader: (6)

With a ported TB, you are looking anywhere from 5 - 10hp. That is what it usually turns out to be. I had one on an old 01GT and noticed a slight difference in sound and performance compared to one that wasn't ported. Hope this helps.

-Mike

Blk02Ls1A4

iTrader: (3)

The rear of the Ls6 was what I was wondering about. It looks like you might have to cut and patch the rear brake booster and map hookup and relocate them. That shouldnt be too awful though, assuming all you have to do is cut off the very back part there.

Taz34SS

iTrader: (2)

When I had my L67 TB ported by ZZP, I noticed a few things.

1. Alittle better pedal response

2. I did gain about 6 hp total

Overall, I feel that if I can get this done and add any HP, its worth it in the end.

Watch, I will get this done and then Fast will come out with a intake just for the LS4's...

TiredGXP

iTrader: (2)

I took a few more pics this morning. The power steering reservoir and the vacuum fittings on the back of the LS6 intake will want to share the same space. More mods to do, Yippee . Wonder why GM didn't use an electric power steering rack on the GP?

Here's a pic of the back of the LS6. The mount for the MAP and brake booster is detachable, so this can be removed and blocked off without too much trouble.



Here's a pic of the space available at the rear of the LS4 manifold. Maybe a quarter inch of space between the #1 intake runner and the power steering reservoir.



This next pic shows how the brake booster (**EDIT: this is not the brake booster, I couldn't trace it after it disappeared under the alternator to see what it hooks up to**) and MAP sensor are mounted.



(I know it's dirty, just took the engine cover off for the first time yesterday - that's three years accumulated muck.)

jarcher

if you are needing the fuel rail from that manifold i still have that kicking around if you're interested

TiredGXP

iTrader: (2)

Jeff, yeah, I'm interested. I still have you number, I'll give you a call sometime within the next week.

Taz34SS

iTrader: (2)

I wonder how hard it would be to have a custom High velocity intake insert made for these cars? Or would it not be worth it?