tahoe

There are as you all know a lot of cam choises and know how if you want to make more power in a LSx engine.

But what if I am happy with the power, and want to maximize the mileage,
how should such a cam be designed?

How should the valve events look like for max economy?
(I find it difficult to belive that the stock 5,3 cam is the ultimate for economy)

//

NoGamesLS1

iTrader: (16)

I know guys are getting some great highway milage with the 224/similar cams

tahoe

Just to clarify, in my question I ment BETTER mileage than stock.

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LS1BirdDRG

My car has a 224 cam and has achieved 28mpg on multiple road trip occasions. Of course I drove fairly easy in 6th gear with cruise on about 70-73mph.
The good tune helps alot too. There's alot of cars around with garbage tunes and unhappy owners as well so results vary.

Patrick G

iTrader: (14)

Moved from Advanced Tech. More eyes in here.

The factory is saddled with not only trying to give their cars the best fuel economy possible, but also to have them emissions legal and made to last hundreds of thousands of miles.

A cam built around ideal fuel economy would be especially good in a narrower window of operation. Since your best V-8 fuel economy occurs under 2000 rpm, you would want to optimize the valve events to make your engine have the lowest BSFC in the 1200-2000 rpm range. Your mods and tune will play a big part in what those valve events are.

In general, an economy cam would have small duration like the stock cam, but more dynamic compression and more overlap (think narrower LSA and advanced intake centerline). Overlap will help fuel economy to a certain extent, but not emissions.

tahoe

Ok tanks Patrik G, that was what I was looking for.

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hammertime

iTrader: (1)

Patrick,

I noticed a while back the new bit in your signature about tuning your Suburban for max fuel economy and power. Since you posted in this thread, I'm curious what kind of economy numbers you are achieving, and whether you think exhaust improvements, particularly LT's, might be of benefit to both.

Hammer

PS - to the original poster, sorry for the

Patrick G

iTrader: (14)

I've picked up 1-2 mpg with my tune in the Suburban, but the power increase is even more noticable. We're up to 286 rwhp with just a tune and airbox which is pretty good IMO. 1/4 mile times are a solid 5 tenths faster and mph is up 3. Headers would help power more than economy, but I'm sure they would pick up mpg's a little. Just not going that route with this vehicle. Quiet cruising is the name of the game.

noah89

Got 23 mpg last tank. See mods below.

Patrick G

iTrader: (14)

I was looking for a Suburban in your signature and was ready to throw out major props, but all I saw was a TA. 23 mpg is lower than stock (highway rating anyway). I average a few mpg better than 23 on the highway in my TA, but of course, I have a few more mods which probably helps.

brad8266

iTrader: (23)

25-26 on the highway in the TA, 232/236 112 lsa cam.

ShortChevy

iTrader: (21)

Pretty sure he isn't talking about fbodys guys, he mentioned 5.3 in the OP and his name is tahoe...

Patrick G

iTrader: (14)

I was responding to Noah89, not to Tahoe.