Alright, I cant seem to wrap my mind around this one. I was reading this thread by DanniBoi about his first car, and saw this clip of the exhaust. How he has a stock 305 carbed. Stock maniflods, stock cat, and NAPA replacement crush bent exhaust in this video.

http://www.youtube.com/watch?v=arXWmtX2Cfw

My car is a 305TBI with complete factory exhaust. No mods at all. It sounds mellow and ***** in comparison. So what I am trying to figure out, is does the TBI induction make the motor sound weak, or is it something I need to do with my exhaust? Because I am figuring that the NAPA exhaust is stock replacement, nothing special.

 

I think the biggest difference between you two is the cam and thats why his sounds like his and yours does yours.

 

So the LG4 has a better cam than the LO3? I thought they shared like the same bottom end and exhaust and stuff.

Just for quick reference, I took a quick video of mine tonight. All origional sounds like ****.

http://www.youtube.com/watch?v=7eavK1Xm070

 

I believe the LG4 did not have a roller cam, and I'm sure the LSA was much tighter then yours. I know the LSA on your L03 was like a 117 and his is a 109. That is probably making the biggest difference in idle sound quality.

 

Man this sucks... I really wanted to find a way to get that white trash trailer park nascar-comin-down-the-road sound easy. I definately wont do a cam swap for it though!

On another note, could the better cam in the LG4 be the reason they get really bad gas milage by comparison? My buddy has an 87 bird with the LG4 and a flowmaster, and he gets 6mpg around town and 12 highway. I get like 15 around town and 25-30 highway.

 

Either that, or its a bad tune. I know that my 91 LO3 only got like 8 city and 12 hwy (but i am also in Southern Cali with its wacky traffic...) But my new L98 is getting 14 city (havent done too much hwy driving recently to get a highway number)

 

I don't know the cam specs of either off the top of my head but....

No, the LG4 is not necasarily a "better" cam, it may have more base duration along with the overlap making it sound different. But our roller cams can have way more area under the lift curve with less base duration since the rollers have steeper climb rates & more rounded lobes versus a flat tappet's peakier lobes.

This leads to making more power with less noise or roughness in the idle, also our fuel injection helps make the engine run smoother than most any carb would be able to do. I remember reading an article about it in Car Craft I think, something about it will pull more vacuum with the same motor & run a bigger cam smoother & such...

An example: I rebuilt my '70 Bronco's original engine once & added an "RV" cam.. tight duration with more than stock lift etc... & it sounded kind of like that 1st vid... a little lumpy & overall decent.. but after frying that motor with too lean a mix I swapped in an '89 'stang engine (I know its a Ferd but the same idea applies) That motor with the stock roller cam made way better power & ran quieter & smoother. Now it has an E-303 with I think 282* base duration & 220 @.050 w/.498 lift, before I added higher ratio rockers. Now that engine thumps its little big bore @$$ off but still makes excellent power off idle through 6000 revs...

But if not for the roller a cam like that would require prolly a 1000 RPM idle & wouldn't make near as much low end.... Ok, so once again I took a simple explanation way too far... oopps, I just hope somebody learned something from it...

Oh & I think yours sounded better than the carb'd one anyway, the other sounded kinda tractorish... I have a supposedley high flow cat on my '91 and a junk dynomax turbo muffler of some sort that sounds like turd...

OH & I remember mine getting 17-18 MPG when I drove partial freeway (@85MPH) and partial city... And I drove from Houston, Texas to NYC once and got about 23.5 MPG going from 80-90MPH the whole way

 

Is that Spring Creek behind you or San Jacinto River.

 

Spring Creek... 2nd Beach... kinda locally well known location. Going out there right now for a meeting actually. We're having an event Saturday.

 

No completely stock LG4 with a (basically) stock exhaust that I've heard ever sounded like that. My '82 LG4 sure didn't and neither did my '83 L69, which was also carb'd and a heckuva lot more powerful than a stock LG4. And neither of my current fuel injected cars('87 LB9 and '89 LO3) sound like that--and they each have full 3" aftermarket cats and cat-backs.

I prefer to take people's word, but in this case I've gotta believe that something isn't stock(cam or headers) or the exhaust is open somewhere, either intentionally or by accident(a leak).

As for mileage, I've always gotten in the low-to-mid 20s on the highway in all four of those cars, which should be normal. If people are getting 12, then they've definitely got a problem or a very heavy foot... or, again, they aren't stock.

Just my