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First, welcome to the BB!

Yes, you can get a lot more performance out of your series 3 Spider... It is really a matter of knowledge (not a small factor) and how much money you want to spend, as it will add up pretty quickly... If done correctly, the results will be dramatic...

Performance-wise, series 3 Spiders still belong to an era when Alfa Romeo and auto manufacturers in general were still struggling to meet USA emission regulations. Hence, while the stock 115 hp (at the crank) is respectable, the OEM set-up still represents a slightly de-tuned state when compared to say, the stock OEM 1974 Spider, which produces 129 hp.

Regardless, the good news is that you can make reasonable mods to get more out of the engine. IAP and Centerline offer proven approaches, and a lot of bang for your buck, although from reading your post (racing cams, forged pistons), it sounds like you want to take your car to a whole different level...

With any series 3 Spider the place to start is with the exhaust system. Since the PO replaced the manifold with headers and the exhaust with a straight pipe, I don't think you need to do more. Headers are a definite improvement over the short tubes of the stock manifold, but I'm not sure why he felt he had to go with a straight pipe. (Even tracks are enforcing noise level restrictions...) Anyway, suffice to say that you car can now breathe without restrictions. (You do realize however, that exhaust set-ups work best at a certain RPM range, and whatever the PO did may not be what ultimately works best for what you will do, right?)

The next step is to modify the head, and here is where some serious power may be unleashed. There are certainly different levels of preparation. I would venture to say that IAP and Centerline heads will probably give you about 80% of what may be gotten out of an Alfa head. When you look at their prices, that is a lot of bang for the buck, for it will probably cost you twice as much to get the remaining 20%. And I would not take the head to any local machine shop, no matter how good they are. In order to truly get the power out of the head, you need to go to someone who has done many Alfa heads and has a proven record. Experience makes a huge difference, and the head gurus do not share their secrets on this BB. They also charge accordingly, but IMO, they are worth the money as you simply will not be able to duplicate their results. (Two heads built to the same specs will be very different if one is prepared by an expert and the other one is not.)

With a well prepared head and some slightly hotter cams (and the mods to the exhaust) your Spider will have very nice power on demand. With just those two mods, the result is noticeable right away.

The next step could be pistons. Stock compression is 9:1. You can get Borgo off the shelf pistons with 10:1 or even 10.4:1. (The 10:1 Motronic design is favored over the 10.4:1, but you need to read up on that...) Borgo is the OEM supplier, well known, and well respected, but their Spider pistons are not aluminum forged. For that, you need to check out the Paul Spruell web site: Spruell Motorsport, Inc - Your online Store for Alfa Romeo and selected Sports Car Performance and Racing Parts and Equipment. (There are also other sources across the pond.) Now, you are starting to get into money... You can certainly go with higher compression than 10.4:1. You may also consider rods, etc. Here too, I would be selective on who builds the bottom part of the engine, and again, IMO, it's not just a matter of specs, and experience counts a lot...

You may run a seriously modified head and engine with very streetable cams and have great power, but of course, if you really want to get everything out of your enhanced engine, then you'll need to do more extreme mods. Here's where it gets tricky (not to mention expensive). You can go with extreme cams, but then you will have to solve the fuel delivery issue, as the L-Jet works with sensors and is not programmable in any way. I've seen some L-Jet Spiders with 11 mm cams, and some ping and some don't. There are also 12 mm cams available for the Spider. Cams cannot be compared based on lift alone, but just so that you get an idea, stock series 3 cams are 9 mm. Whatever you decide, do know that replacing the fuel management system is not an insignificant step.

Besides the fuel delivery issue, and based on your post, it does seem like you realize that all mods have to work in unison, and within parameters that make them all compatible. Thus, you realize that the you may also have to modify (replace, actually) the timing system. When you get to this stage all of this is serious work. I would suggest that you continue doing what you are doing now, which is research options and get to know who does what type of work and the cost. (There are different approaches for sure.) Once you have all the info, you'll be able to decide what will work for you.

Best regards,
 
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