RoyO

Has anyone ever dynoed the difference between a fully cappped and uncapped Borla exhaust system?I was curious.TIA

someday

some magazine did it a few yrs back, on an LT1 i think... full open gave most HP, middle size hole gave similar HP with a bit more TQ at low rpm's, and the small hole gave most TQ, but less HP...

RoyO

Thanks.

General Jack

iTrader: (4)

Before headers, I always kept it on the middle plate because of that article.

Now that LTs are on, it stays fully blocked (all through the muffler).

Hardtop

iTrader: (3)

My car with H/C picked up 6.5 rwhp with my Q-tech cutout open. That tells me the Borla muffler flows pretty well.

Bruce

hondakiller

iTrader: (3)

friend of mine with a bolton lt1 said he consistently picked up a tenth by uncapping the cutout.

Freak

i have. I dont remember the numbers off hand, but I do remember that the spread from the highest to lowest was 3hp and 4ftlbs. and that, oddly enough, wide open was the weakest of all. I belive that the 2.5 inch plate was the best, but Im not 100% sure.

the curves were so similar that it was difficult to tell them apart.

If I ever find the dyno sheet Ill post the numbers

RoyO

Thanks for the info.I didnt think the car felt much different between closed off and fully open.

someday

its mostly a sound thing... i doubt u would ever notice a difference in 3hp... its all in how u want ur car to sound... quiet for the commute and neighborhood, medium for "cruising", and open for the track...

Freak

the only place i ever noticed any difference at all was JUST off idle with the stock gears. i couldnt feel it exactly, but I noticed that the amount of gas and clutch i had to give from closed to open was different. im sure that this could have been fixed with a littel tuning, but it wasnt worth it to me.... going to 3.73's made it pretty much unnoticable.