I am working on a street 914. The 4 cylinder engine will have a 1.8 crank and 100mm bore for a 2073 engine. The compression will be 8:1 and the valves are 44mm and 38mm. I will be running dual 44mm Webers on long manifolds. I want an engine with good torque and awesome midrange. Redline on this engine will be 6000.

What cam should I be looking at?

First let me say that my knowledge on this is limited so I could be wrong. But if you are using the 1.8 heads I think you are somewhat limited by how well they flow. While you may select a cam than could give you the performance you want, achieving it with the 1.8 heads might be difficult. While the 100 mm bore gives you added displacement, if the heads won't flow well enough to get the, what they need to produce all the power they can, you really don't get the bang you want from the larger bore.

Certainly take the guidance from the other experts over mine, but you might get a better bang for your buck by putting money into improving the heads you have now or swapping to 2.0 heads.

Certainly a cam that is designed for carbs will help your performance but a smaller bore with good flowing heads may get you where you want to be better than a larger bore.

But as it has been said, the only thing that beats cubic inches is cubic dollars, so it is a tough choice to spend the additional dollars!

If Jake still does cams his (9350? carbed mid range) sounds like a pretty good choice. It is what I have in my car.
If not, the WebCam 494.

You are going for a path not often taken with that bore size. I also think you are combo-ing yourself in for a top-end engine with those valves and carbs, instead of mid-range. I had valves similar to that on my 2056, and dual 44 webers. It ran, but all the power was 3K and up. It was doggy unless I kept the engine spun up.

I went down to 40mm webers and that helped, and then took my valves back done to stock 2.0 sizes when I had the heads done.

Zach

The web cam 86A will have good low to mid and have great upper RPM power, even a bit past 6k RPM. Can most likely get away with single HD valve springs too.

The web cam 494 will have solid all RPM power but after say 6K-ish RPM the power would probably begin to taper off. Though with bigger valves power would taper off a little later.

The web cam #270 will have similar power to the 494 with a bit more upper RPM breathing ... that #270 is the one I installed on my 2056cc with 44mm intake and 38mm exhaust valves and counter weighted crank ..... my rev limit is 6500 RPM ......

The guy that first speced this engine was going to autocross it. I inherited it. Funny the cam in the engine is very close to the 494. Perhaps I should just run what he had?

Sounds like a reasonable plan...

--DD

If you have known matching lifters…

OK what about springs. I measured the springs in the head to have 130# at the installed height of 1.5". Seems kinda stiff to me. Can I use stock springs with the 494 cam?

No.
Use the HD springs.
And pay attention to what Jake said about the matching lifters. VERY important.
Zach

I know the cam was reground by Reed cams. I have no idea what the lifters are. In searching the subject it seems a company named Johnson had some bad lifters on the market about 2003. The engine was built about 2006. Any suggestions on the lifters?

Johnson lifters never failed us… It was after Johnson went out of business that another company (high lift) made a replacement that failed quite often.

If you have unknown lifters, you can't risk it. Do you have pics of the lifters? I can probably ID them. Post pics of the faces, sides and pushrod cups of the lifters and I'll review them for you.

Thanks Jake,

I sent the pictures to your info email because I couldn't get them to post on this forum. Well I posted it and here they are.....

neilca

Jake and I have been trading emails on these lifters. To summarize, these are Febi lifters. He suggested I replace these with Web Cam lifters which better match my cams taper.

Febi lifters only like lobes without a taper…