Fuel injection expensive? What the...?

Andrew, they don't spend any money on R and D on Carbs now...so I don't know where you get the idea that the Carbs are expensive. As for the belief you cant polish intake manifolds, they are smoothed up a lot more than stock trust me.

A sealed fuel injection system may very well not be more than what they are spending but why ask engine tuners to learn new tricks and do more research on tuning? THAT costs the money. The guys building the engines know the Carb like they know their own hand and they cant do much more than change jets with it. They are forced to concentrate on cams, timing adjustments and port and polish work to get the power. Adding another learning curve with FI will just increase the need for more dyno time to gain??????? NOTHING they really don't get already.

An intake manifold for a carb isn't polished to a super-smooth finish inside the runners.
The intake is ported to open it up & the ports matched to the heads.
A course grit grinding stone is used to avoid "puddling" of the fuel-air mixture.

As to carb modifications, nascar limits venturi size but the team can change the jets, rods, accelerator pumps, etc.
Many little tweaks can be made to the carb to adjust the carb to a projected power band.
Track size, degree of banking, etc. will be used to determine the power band.
NOTE : Holley sells the nascar teams a carb specific for nascar & it is legal out of the box. :D

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Originally Posted by RaceFanStan

An intake manifold for a carb isn't polished to a super-smooth finish inside the runners.
The intake is ported to open it up & the ports matched to the heads.
A course grit grinding stone is used to avoid "puddling" of the fuel-air mixture.

As to carb modifications, nascar limits venturi size but the team can change the jets, rods, accelerator pumps, etc.
Many little tweaks can be made to the carb to adjust the carb to a projected power band.
Track size, degree of banking, etc. will be used to determine the power band.
NOTE : Holley sells the nascar teams a carb specific for nascar & it is legal out of the box. :D

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Stan, would you then agree with me though that for the most part, most of the R and D on Carbs with NASCAR teams likely has been done and it is more of a black art to set jets to accomodate humidity and air pressure on the day of the race? I don't see money spent on Carb development but I do know that the amount of dyno time that a fuel injected motor would cause in the first year would cost a lot of dough?

Yes, I agree there is no R&D for carbs.
All the teams will have notes with what jets & etc they ran @ which track.
If weather conditions (humidy, temperature, etc) are different than usual @ the track ...
then the engine man may make a decision to run different jets and/or etc.
With information sharing so prevelent, even the new teams will have access to manufacturer's notes on the carbs.

Which is why then McReynolds is right on the money that Fuel Injection would increase costs, because the R and D needed to make hp and learn what they need to do would HAVE to be done and that would cost money for the first couple of years....