ChopperDoc

So I just got everything on the top end back together, heads torqued, headers torqued, and all the stuff on the front back together. As we go to install the intake, we realize there is about a 1/16" gap on both sides. Heads were shaved down .035".

So out of curiosity, we set the stock intake on there, it fits fine. So now the fix is apparently to shave the underside of the 102 to avoid it sitting on the valley cover. This is the easiest fix, aside from adding spacers to the heads to get it to sit higher.

Anyone else had this problem before?

Engine is a LS3, stock 0821 heads.

ChopperDoc

Has anyone else had this problem? I can't be the only one that's tried this.

ChopperDoc

Well I went ahead and shaved the bottom of the intake. A flapdisc and a grinder made short work of gutting the bottom of the valley area. Now it fits again perfectly. I should also mention I already have button head screws on my valley cover, but there still wasn't enough room with the .035" milled heads. This is what I did if someone else runs into this problem...

big hammer

My mast ls3 heads are shaved .055 and my fast 102 intake still fit. But I wouldn’t want to go much more

ChopperDoc

Guess you got lucky with that. Mine had a big gap. Also had some deck work done way back when too, to ensure a flat surface. I have a stock valley cover, with the button head screws from fast on there. May have worked to change that out with a countersunk version. I saw this as a cheaper and faster alternative since it really wasn't all that much I had to take off. I just threw some foam under there like the stock one and torqued it down. Fits awesome.

Did you also have the heads reangled at the intake ports? According to TSP, anything over .042" requires some milling on the intake ports to change the angle to match the intake. That's why I went .035", since these have been surfaced before, about .003, so I'm really right at about. 038". Angle still matches and everything. Compression is at 11.9:1. 8.2 DCR. I'm trying to stay on 93. This is a street car.

big hammer

The angle was slightly off but the intake just flexes and seals fine when you torque it down. That’s pretty much where I am now with my compression as well now.

98CayenneT/A

I had similar issues with my 102 msd on my Ls1 with heads milled. 030". Just certain hoops ya gotta jump through when running 102 setups

01ssreda4

iTrader: (96)

Mine dropped on once i removed the locating dowels on the underside and mine were milled 40.

Darth_V8r

iTrader: (4)

Those locating dowels can be frustrating for sure

ChopperDoc

In my case the dowels lined up just fine, luckily. It was just sitting up high on the valley cover, floating around side to side. It just couldn't sit down flush on both sides at the same time. I could push it over to one side and had probably 1/8 to 1/4" of room on the other.

Gutting the ribs under it worked great. They were actually not flat, and had a curve to them near the ports. I just went ahead and made them flat across, and it popped right on no problem. It just needed some room to sink down.

I figured it was quicker and cheaper than ordering a countersunk valley cover and hardware. And even so, that may or may not have given me enough room. Gutting it left me plenty of room, and was done in minutes. Everything is back on now, and torqued. Just have to build my cold air intake (from scratch lol) and get this pig running again.

DietCoke

iTrader: (18)

What did you hit it with, a belt sander?

G Atsma

As said above., a flap disc and grinder

NitrOmm

iTrader: (1)

I had a similar issue. Once I managed to get intake to fit, the injector ports didn’t line up properly. A portion of the fuel was actually spraying on the deck & pooling up near the port. Note: take a look down the injector port with a flashlight. Avoid the hair pulling I experienced before you button it all up.

Hardcoresoldier

iTrader: (2)

I removed the dowels from my LS3 intake and it went on fine. my LS3 heads were milled .036

ChopperDoc