Vac pumps???

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01-23-2009, 09:03 AM

#11

hammertime

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Quote:

Originally Posted by doorracer

Quote:

Originally Posted by hammertime

These guys got it correct above. I've had motors on the dyno with proper evac setups and then swapped them over to the vacuum pumps. 1st motor 548 went from 959 to 971 this was no low tensions and a carb. 2nd motor was my current 582, made 960 without and 979 with it. 548 was a star pump with a built in regulator, second is a Moroso 3 vane without a regulator at all. I also run the terminator and have NO milk in my oil but you can do this with or without the pump. I think they are a great idea with injection just because the crankcase pressure is increased with the injection and it will elminate any issue there.

David,
Why do you say this and what do you think would cause it any different from a carb?

Curtis

The injection is a different animal then a carb, spraying fuel directly into the port, on avg I'd be you'd see 20-30tq gain and sometimes 20-30hp gain across the board over a alky carb.

01-23-2009, 09:06 AM

#12

hammertime

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Location: Coldwater, MI

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Quote:

Originally Posted by dparker

Makes me wonder if the $1000.00 was well spent on the vac pump. But then again seems like I always get buyers remorse after I purchase something over $1000.00. At least it looks good on the engine.

You can always slap a set of valve covers with breathers on them and run a evac tube bet it slows down 3-6 hundreths with doing anything

I think you made a good choice, breathers get junk in them and dont pull as well, constant vacuum instead of things changing. Little things like these that make a car deadly IMO 8)

01-23-2009, 10:02 AM

#13

curtisreed

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Quote:

Originally Posted by hammertime

Quote:

Originally Posted by doorracer

Quote:

Originally Posted by hammertime

David,
Why do you say this and what do you think would cause it any different from a carb?

Curtis

The injection is a different animal then a carb, spraying fuel directly into the port, on avg I'd be you'd see 20-30tq gain and sometimes 20-30hp gain across the board over a alky carb.

We run both so I understand the difference of the two systems. We changed from a Demon to a toilet on a 406 we have, this motor made 720hp dynoed with the Demon. We picked up zero e.t. or mph when we switched and got the tuneup right on the toilet. It all depends on how good of a tune you have to begin with if you pick up. I'm not trying to be combative I just didn't see how you could say the crankcase pressure would increase with the injector, I'm always interested in learning something.

Curtis