What can I add to my 1915 cc stock engine?

Look for a set of 36 DRLA (or some other appropriate size) Dellorto carburetors. BTW, I'm not endorsing the pair being sold but I linked it as an example. I can't believe I'm saying this but EMPI has made a Dellorto copy and it has gotten good reviews but nothing beats the real deal. You could also upgrade your Bosch 009 distributer to a Magnaspark so you get consistent spark.

Others with more experience will chime in here soon.

I suppose it also depends on what you're willing to do. You could drop the engine and rebuild it bigger or with more performance oriented parts and get some more oomph out of it.

Depending on the heads, and assuming it's a stock cam (I think Vintage uses stock or near-stock cams?), I would thinks a set of ratio rockers might wake it up some. I'd verify the valve springs and cam before choosing between a 1.25 and 1.4 ratio. But like Clock said, if you want serious power you'll be into a build, and if you're going to build it you might as well stroke it, and...

I'm going to guess that the VS 1915 (at 85hp, according to their website) has a mild cam (Engle W100 or something similar), stock dual port heads, stock 1.1/1 rockers, dual 1 barrel carbs (34 Ict's?), revs to about 5,000 rpm with power and as Gordon said, is a good midrange performer. You could, as Robert suggested, put some small (36 or 40 mm) dual Dellortos or Webers  with a better distributor on it, which together will make it noticeably smoother throughout the rpm range and nicer to drive (with a little more power in the top 500 or 1,000 rpm), but there's no kick in the pants horsepower increase here. A little, but nothing huge.

Some 1.25 rockers will add a bit more upper mid range/top end, and with the dual Webers/Del's (and new distributor if you choose) will be a modest but noticeable increase, not cost a fortune and be easy to do. You'll need new pushrods (different length) with the new rockers, and I recommend spending the extra $$$ and buy the high performance aluminum (Aircooled.net has some nice ones, as does apparently CB Performance). The engine will run quieter than with the chrome moly pushrods and, being lighter, the engine will rev that little bit higher (and be that little bit easier on the valve springs). 

Some ported stock valve (35x32 mm) heads would go really well with the carbs and rockers, and together with a slight compression rise will now probably approach the power increase you're looking for. There are a number of people out there that can do a really decent ported head, and Steve Tims (Performance Workshop) does a "Super Stock" 37x32 head that's supposed to work really well (hearsay only; I've never actually seen or met someone running those heads). The temptation here will be to go to bigger valves as well- a lot of people will tell you it's a waste to put that much work into heads and not increase the valve size, but you're looking for driveability and throttle response throughout the whole rpm range here, not only upper end power at the expense of low end/mid range torque (where you spend 95% of your time driving). 

All of this will cost in the neighborhood of 2,000- $2500 and add 15? 20? 25? horsepower, which you will feel and be a lot more fun. Alan is right, though- a 21-22-2300 cc, big valve'd stroker (140? 150? ???hp) has that much more power from idle on up and will make your car really rock!  think big, evil laugh here!

Hope this helps. Al

I just got a VS with a stock 1915 with external oil cooler and trimill exhaust. I have upgraded my distributor to MagnaSpark 2, just because I wanted a smoother idle and reliability. After researching bolt on upgrades like Al mentioned above (rockers, Springs, heads, carbs, etc..) I have come to the conclusion. After you do all the upgrades you will be around 1/2 the cost of 2110. With my lack of confidence in the build quality of the engine, I see it as throwing good money after bad. I am going to bite the bullet in a year or so and get a 2110 from a good builder, and resell the 1915. If I am lucky I can get a couple of grand from the 1915 and recoup some expenses reducing the hit to the pocketbook. I know it wasn’t the answer you were looking for but just another opionion. 


I was in the same spot you are last year.  I decided to build my own 2276.  I had no experience what so ever building an engine.  I took the 1915 out and put it in a corner of garage and built a long block.  I was going to use the 1915 case, pistons, rods, cylinders, and jugs to save about $2,000 on the build.  Wife  told me not to touch that 1915 in case I screw up the build.  So I built the 2276 from scratch.  The motor turned out great.  I got a lot of help from the guys on this site plus EZGZ and VWDarrin youtube channels.  I did have a few problems but worked through them.  I really enjoyed the build and learned a lot.  I would do it again.  Actually, I might take that 1915 sitting in corner this winter and build a little more radical motor than my first build.


Have you looked at CB Performance Builders Choice engine kits?  They supply pretty much everything you need in one kit for a long block and you assemble it.  They don't include carbs or exhaust. They have a  180 hp kit for just under $5K.  A hpmx 44 carb kit would cost another $500 or so.  When you are done sell your 1915 long block.

Another option would be to look at buying a long block already assembled.  John at Aircoolednet has some great deals.  His 2276 long block is $4,795 and he will build it mild or wild to your choice.  

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