cmac06

iTrader: (16)

I've seen a few posts on here about intake manifold flanges, and them being available. The one thing I can't find is who makes them. Anyone know? I need some to make some spacers to bolt down my manifold. I spoke with FAST, and they said it was fine to mill the LSXr, but every machinist I talked to said it was a crazy idea to attempt to grind the plastic manifold.

KCS

iTrader: (20)

I'm pretty sure Comp (or one of its sister companies like RHS) makes them.

How thick do you need? For what it's worth, I noticed that the truck engines use a plastic spacer between the head and manifold. It looks the be about 1/4" thick. Might be a better option that a pricier set of aftermarket spacers.

cmac06

iTrader: (16)

Thanks, for the update. You wouldn't happen to know the part number. I called FAST, and they only have the spacers for the tall deck blocks. And like you said, they're in the 250'ish range, so a cheaper option would be great.

soundengineer

iTrader: (16)

The truck engines don't use a spacer..
Its the actual gasket that is that held in a piece of plastic instead if being in the manifold..

Its worth a shot to try.. but its only about 3/16 thick.

cmac06

iTrader: (16)

Thanks for the gasket idea. I see Fel-pro makes a thick gasket part number 1312-5. Is that thicker than the stock gasket?

KCS

iTrader: (20)

But if you use it on a car manifold, it's a spacer. Voila!

BigDB

Is the truck gaskets for the FAST sold separately from FAST? I need to space mine up a bit to get the ports lined up.

cmac06

iTrader: (16)

All FAST use o-ring style gaskets. I found a company to make spacers in any size out of aluminum. I ended up going with a 1/8" thick spacers. I'll post pics when I get them.

cmac06

iTrader: (16)

Got the spacers in from flat out gaskets. Test fit with FAST intake, and it still fits like junk, so I grabbed the old truck intake, and it bolted down just fine. What gives? Is there an issue with fitment using the FAST? I'm about to throw this junk in the trash, and just run stock. With the intake on, I still won't be able to put injectors in as it is hitting the top of the port. Here are the spacers if anyone's interested.

Marc 85Z28

iTrader: (8)

I'm pretty sure that's only for the tall deck blocks.

To the OP: what's the rest of your setup look like? What's been done to the heads and/or block?

cmac06

iTrader: (16)

^ Yes, they only work with the tall deck blocks.

I had the heads milled down about .045" total to get to 63cc. Everything else was at stock spec. The manifold bolted down to another long block, so I figured my block was milled to fix the deck. The pistons were under the deck when I measured, so I assumed it was close to spec. I don't have the measurements in front of me, but I needed to get .045" gaskets to get the clearance where I needed it.

soundengineer

iTrader: (16)

if your heads are milled your alignment problems are because the heads are sitting lower...
spacers would only make the problem worse.
with milling the heads .045... the only thing that fixes your issue is to Mill the intake to match
Mill the heads, mill the intake
raise the deck, add to the intake

the problem becomes that you went for extra compression in the wrong spot by going to a milled head to reduce the chamber size
should have gone for different pistons to change compression.
otherwise, as you have found out, intake to head geometry gets messed up.

cmac06

iTrader: (16)

Yeah, no intake is made to be milled from what I can see. Would like to go with Holley, but they specifically say to not mill. So now it is looking like a sheet metal intake is in my future. I don't want to have multiple things that only fit this motor.

Would you recommend getting a custom intake, or milling the heads to work with the stock manifold dimensions?