NBM2k2SS

iTrader: (2)

Just woundering if it is ok to run a cam on stock exhuast manifolds?

777

iTrader: (21)

you can if you only want to gain about 1/4-1/2 the power out of the cam...seriously the exhaust manifolds really take away a cam...depending on size of the cam...definatly get the supporting mods before the cam you will thank yourself later

ss rally red

iTrader: (8)

I ran a Hotcam on stock manifolds and picked up .5 tenths and 6 mph on a lid/LM & 4.10's. 13.3's @107 vs. 12.80's @113. Stock time was at Beech Bend at the 02 gathering at Bowling Green in Aug. of 02. HC times were at Gafba. shootout in Aug. of 03. Same temps/conditions.

01_SuperSlow

iTrader: (7)

stock exhaust manifolds will choke an aftermarket cam. Do LT's first, you won't regret it. Even the stock cam benefits from the addition of LT's.

2MuchRiceMakesMeSick

This is a terriable idea not only from a hp/gain stand point but from a tuning stand point.

Taspeed

iTrader: (1)

man...give someone a call at fastech...hell any of the sponsors. You can find a cheap set of longtubes for around 300 or so. Pacesetters, or hookers. I personally don't care for the flowtech's, but they are cheap as well. Really pointless to do a decent cam without headers.

Flareside

You can get good gains from a cam along with stock manifolds, but it all depends on your goals. You'll need a cam with a shorter, more aggressive intake lobe, and a longer exhaust lobe (wider split) that can deal with the extra backpressure of a stock exhaust. The popular cams around here, "224/228", etc., we're never designed for a stock exhaust, so when people run them without headers they're disappointed.

Headers are not without trade offs. They let more heat into the car, they're louder, most dealers won't touch the car with them (if you have a warranty), they usually reduce ground clearance and scrape on bumps, the 02 sensors sometimes complain and then have to be disabled, etc.

jimmyblue

iTrader: (11)

I think it depends on how much cam and what else is up
with the exhaust. If it's a smallish one with an exhaust bias
then it'll be a decent wake-up, without emissions / tuning
hassles that headers bring. Sure, it won't give you as much
output improvement as a "proper" exhaust. But there may
be other considerations that make it not-that-stupid (like,
say, visual smog inspection *****).

If you have a good reason for staying stock-exhaust I'd
say to get some help in selecting a sensible cam for that
reality. It probably won't be what people now consider
"decent" but something like an Old Man or Stealth, Z06-
like would not be such a terrible thing.

I'll probably be sticking with manifolds (and gutted cats)
for a while, but putting on heads and a baby cam. I know
it'll be exhaust-limited but I can live with that, until those
$400 stainless headers start cluttering up the market

NHRATA01

iTrader: (10)

You can do it, I ran a T1 (.558/221) on stock manifolds for a year, and had solid gains - trap went from 108 to 111ish, made 365 at the wheels on a dyno.

I would not run any monster .600" lift, 230+ duration cam though, that would be a waste because it won't breathe. But if you run something moderate like a TR224, B1/T1, hotcam, or something say <225 duration, <.560 on lift, I think you'll have some nice gains on the stock manifolds. Esp on an '00+ car with the better design.

Patrick G

iTrader: (14)

Yes, don't listen to the guys that say you HAVE to run headers. You don't. If it's your choice to stick with manifolds, then just make sure your cam has 0 degrees of overlap at .050" lift or LESS! The overlap of aggressive cams need to breathe and therefore need headers. If you keep the overlap in check, you can make a lot of power gains and still keep your stock exhaust.

As an FYI, the TR 224/224 112 cam has 0 overlap at .050". It's about as big as you'd want to go.

nuzee

iTrader: (2)

I gained ~3 mph in the 1/8 but only 1 mph in the 1/4 traps by swapping to the CompCams 206/212 cam. Then I added 1.85 rockers and gained another 2 mph in the 1/4. So I went from 107.5s to 110.5s with just the cam & rocker arms on stock manifolds & cutout. I've proved to myself that there is room for cam-only improvements using the stock manifolds. But as others have said, you shouldn't go too radical on the overlap.

HumpinSS

iTrader: (1)

I did a Fm13 on stock manifolds and the car slowed down and ran like ****. That is what i dgot for being cheap. After the headers it was liek a night and day difference