BB512i engine air intake

I have heard of great results converting stock 308 gtbi's which were real slow dogs to motec fuel injection systems. Since a bbi is not slow but has the same low tech and by your description hastily(poorly) engineered FI system there are probably huge gains to be made by straightening out the airpath and improving the fueling. Apparently BBI cams are relatively flat compared to bb ones so that the stock injection can work.

Its one of those thigs once you start you might as well finish. So figure a motec system installed for 4gs, an exhaust, although Frank you already have an ansa, and maybee 20% more hp with much stronger power and response across a wider rev range. The question is who of us boxer owners is going to forgo fixing their old system and go for a new one. I guess someone not planning on selling. And then of course the tires and brakes would be the next weak link. At the end though you might have near gto performance in a highly charismatic boxer.

 

Okay, I'm no expert but I question this. The most direct air path is no airbox at all, and as we know that will not give you a happy engine. All the bends in the pathway has the effect of giving a uniform airflow by the time it reaches the cylinders (or carbs). As long as the volume of air is sufficient, I think the path it takes to get there makes for a more tuneable engine due to consistant air flow. (Of course, if there is too much air restriction then the engine won't get enough air to make maximum power.)

Ken

 

Check out the bblms. They do away with the stock boxes for some pretty wild intake scoops!

That said, air is like water, the new flow will replace what is sucked in........they don't smash flat from vacuum!

 

A state of the art modern injection system would be an interesting 512BBi renovation.....not for the faint of heart I'm sure.

My gf's brother was by with a old 50's Pontiac street rod, popped the hood and said "Look!"

I thought "hmmmmmm, x2 for a 308", x3 for yours!

 

bill pollad of sport auto in gaylordsville , ct told me of a conversion he did w/ a bbi and motec efi.

he said it was a pricey way to make a boxer really wake up!!!

a bit over 10k but it would be worth it if you were not intent on being original.
it could always be put back to cis.

 

bill pollard...typo!

a great boxer guy that really knows these cars!!

 

I talked with Bob Norwood about the cheapest way to make horsepower gains with this engine: Injection/cams/compression vs a basic turbo system, and the turbo wins hands down. If not overdone 600 HP is probably reliably possible without internal and drivetrain modifications.It can also be taken off when the car is sold ( we wont tell anyone ). You are absolutly right about the convoluted path the air takes to get into the cylinders.

 

Hi........

Wonder if a supercharger or two superchargers might work better than turbos for a Boxer. No lag !!??

Of course, where would you put them ?? Any modifications to drive train to take more torque ??

Frank.........23005
www.masiarz.net/bb_resource

 

Convoluted path or not the main problem is still the power killing CIS system and the RV cams that are required to make it work. If you like the way turbo motors respond (I don't) that would be great. I think the hot set up would be a modern electronic system and go to a set of carb BB cams. The throttle response you would have when dialed in would be unmatched by anything else wearing BB emblems.

 

Stated peak hp and powerband are two different things. I have never tried a bb but the person who works on my car says they have much more zing on the top end. Undoubtably the cis fills in the middle range and the cams help mid range tourque, however it might be possible to get the best of both worlds.

As all things with boxers its hard to say what the real benefits are between a bb and a bbi because setup is so crucial. But if we extrapolate to the 308 something was definatly lost in the translation to cis, although a 308 is a much more reliant on revs for power and us spec cars had cats and boxers never did. So maybee a bbi didnt suffer with cis too badly. Or possibly a bbi with a free flow exaust and well setup is better than a bb, or maybee a modern injection with bb cams gives the top end rush of a 365bb with the tourque and smoothness of a bbi.

 

That is a total BS number. The Ferrari and Lamborghini factories both made a lot of bogus claims when they were switching from carbs to FI to keep people coming in the showrooms. Go side by side with a carb BB someday, the difference in power is considerable.

 

A bbi is reral sensitive to setup, hence period reports of top speed anywhere from the low 160's to mid 170's. My one ran neck to neck with a daytona which accorting to myth is a faster car.

The real point for me is that a bbi with relativly minimal enhancements can be made a much more enjoyable and faster car, which can be easily returned to stock for the market revival in about 5-10 yaers when it becomes a classic like a 275.