mdrburchette wrote:James, I talked to the guys at Redline Weber about using the TB's instead of my 40 IDF carbs and for $2600, which includes two cast tb's, all sensors, ecu, fuel pump, regulator and distributor, there was no real hp gain. The only advantage would be driveability until the engine's warmed up and maybe better throttle response in lower range. I think I'll just stick with my carbs.
Not to sound sceptical, but it makes perfect sense that someone who's bread n butter is made up more from carb sales than FI might suggest that. It's a good selling job...
I won't disagree that price is a
major factor when considering FI because a good system is more expensive than carbs. And let's face it, carbs make inexpensive horsepower, and they're simple which is why carbs are such an appealing option. But the rest of what you've said, with all due respect, is inaccurate. Both systems have their advantages and disadvantages. A simple dual carb setup for the street is nice, cheap, easy, and works well. But don't mistake them for being superior to FI, they're better than a single throttle setup but they are not better than multiple TBs.
FI systems provide benefits in more than just drivability, although that alone is huge. Throttle response, assuming the FI is correctly set up is better
everywhere, not just down low. Ever try getting a motor with big cam specs and carbs to idle consistently? How about emissions testing? These are some other advantages that electronic engine management provides. As for that power? best thing to do isto obtain a quatitative measure from a dyno. As an example, my buddy just switched from 40mm SK racing carbs on his GT-4 car to TBs with megasquirt (not my personal favorite) and horsepower figures went through the roof in comparison.
The idea of using individual motorcycle TBs is not new but it certainly works well. I've seen a number of of these setups and the manifolds were simple automotive tubing between the TBs and a truncated stock manifold.
Point is, this is not an expensive conversion to do and it works great, Though I've not seen anything like it on a Spider, I suspect it would not be to complicated to do.
There are naturally more pricey FI systems available and they will deliver big gains but you'll probably spend as much for this equipment as you did to buy your whole Fiat. It is also more time consuming to set up a good FI system correctly but there are certainly measurable benefits.
