Height of a 3.0L SC CIS intake from base to top of air filter housing?

[10 GT3]

I am doing an engine swap project with my old 911 SC 3.0L drivetrain. We know that will the stock CIS intake is it going to have a clearance issue. I have a set of 46mm PM ITBs that will be going on instead. I can figure the height pretty easily for the PMOs with the intake and filter options. Drivetrain is right now in remote storage, so not where I could easily measure it myself. I just need the height of the stock 3.0L CIS intake from base to top of the filter airbox to figure out the last piece. I would appreciate if anyone could share this height. Ideally, I need to be 4"+ below the height of the stock CIS airbox. Thanks

[Mark Salvetti]

My engine is on a stand, so easy to get you this dimension. The highest point is the top of the rubber boot. I measure 14.25 inches from the base of the intake runner (where it bolts to the head) to the top of the boot.

If you want the edge of the air filter housing (because you are replacing the fuel distributor and the boot with ITBs), then that is 2-5/8 inches lower, so 11-5/8 inches. If you are keeping the snorkel, that is a bit higher.

This is a 1979, so a large intake runner engine.

Mark

[10 GT3]

Mark,

That height to the top of the rubber boot works. I was originally thinking to the top of the air filter housing top lid installed. I couldn't remember if the rubber was higher than the filter lid. Looking at a couple pics it does appear to be a little higher.

This basically tells me I should go short manifolds as I am targeting a -4" total height. The ITBs are 5" tall. Shortest manifolds are 3", part # PM-0909. Shortest oval filters are 2.25". This combo will get me right at 10.25", -4" total. The 3" manifolds only have 38mm ports at the heads, so need to be port matched to 39mm. PMO makes a 4" 39mm to 46mm manifold that doesn't require any porting to fit on our engines. There are also options to have an even shorter height. My PMOs have 2" horns. I could go to velocity stack foam filters that take up almost no height vs the oval filters, or even go to shorter 1.25" horns to get another inch if I need it. This answered the most import piece of info I needed, whether to order short or tall manifolds and they need to be short.

Thanks

[PeteKz]

The height of the CIS is not what you need to worry about. The deck lid slants up to the front and the CIS sits forward on the engine, so it clears the lid (it's mostly under the rear shelf). ITBs or carbs sit straight up. You will need to figure out if the ITBs, including manifolds and air cleaners will clear the lid further back. Look at the ITB threads, and you should be able to find the same setup you are contemplating and see what they used. Duck tail or whale tail lids have more space further back too.

[10 GT3]

Originally Posted by PeteKz

The height of the CIS is not what you need to worry about. The deck lid slants up to the front and the CIS sits forward on the engine, so it clears the lid (it's mostly under the rear shelf). ITBs or carbs sit straight up. You will need to figure out if the ITBs, including manifolds and air cleaners will clear the lid further back. Look at the ITB threads, and you should be able to find the same setup you are contemplating and see what they used. Duck tail or whale tail lids have more space further back too.

The slope is not an issue for me as we are not putting this drivetrain back in a 911. It is going into a VW Van, where we don't have the sloped engine cover issue. We have an overall height issue as a problem instead.