ealoken

Hi guys.



Im slowly building a 16V 3.1L turbo engine.
Next on the list is new camshafts.
600bhp street / track car.

Any recomendations on what to buy and why?


Catcams can deliver cams + belt and new pulleys, removing the camshaft chain etc.

951and944S

Hi ealoken, interesting, I have the 12mm/11.55mm 5220213 from the S2 menu for a 2.5 16V build.
High quality stuff.
The valves are tiny and light but anything past these lifts, even Cat recommends solid lifter, springs and light weight retainers.

The cams are hollow and weigh considerably less than factory reweld option.

I have a pay version of engine modelling software I might have time to run these cam options through for you.
Along with these specs available from the sheets, I'd need intake/exhaust port diameter, valve diameter, bore/stroke, compression ratio,
as well as accurate measurement of distance from valve face to port exit (on center), header primary diameter/length, peak target rpm.

I would assume Cat can help you with this more easily.
Round up the specs I mentioned and ask them to help model best option.

Don't know in my case (race class) if this would have been a legal option for me, but had I investigated the 968 menu, I may have gone this route and if my intake cam started as an identical blank as exhaust, with key slot, I may still inquire.

Braymond

I just received my order from CatCams recently. I chose the 3.0L S2 cams - 5220212.

Just be aware these cams are specifically designed for naturally aspirated engines.
Maybe you've already done the research, so I could be out of line here, but I think the 16v turbo cams would not have the overlap (11* on your chart) between the exhaust and intake. It may be that using the stock 16v cams from an S or S2 are better for a turbo 16v build.

Good luck with the build and keep us posted!

ealoken

Thanks, it's a long way, first i need to get all the parts sorted, and to Finnish my 2.5L big cam 8v engine.
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here is the cam i was supposed to post, to make a good turbo engine, it needs respons and long poweband, like a mid-high NA engine, planing on rev limiter 6900-7100 ish.

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Braymond

There have been quite a few successful 16v turbo builds over the years. As a start, it may be a good idea to read some past threads about those builds as those folks have already worked through the technical challenges. One build that comes to mind is the Refresh951 build here: http://www.refresh951.com/EngineBuild16V.htm. Shawn got close to 600bhp.

I'm certain you can find a lot of threads and discussion about 16v turbo builds here in the forums if you do a search. Also, Michael Mount is very knowledgeable about both NA and turbo builds and is very good about sharing his knowledge and experience with the community here. He also has posted details of some incredible builds here in the forums over the years.

IMO, it's going to be easier, faster, and less expensive to complete your build for you to start with a "recipe" before you begin buying parts.

-Bill

ealoken

Hi Bill, thanks for the pin pointers
I have parts from Gustafs old WTAC engine, so the block is sleeved, 3.1 cranck, carillo rods and JE pistons.
Turbo will be a GTX3576g2 (already on my 2.5 8V engine )

I have done some searching, but it`s common to use the stock cams.

Erik

Ps, less expensive and Porsche 944 does not align in my head.