Terry Burger

iTrader: (4)

I'm wondering what the high side is for heads/cam/bolt ons and stock exhaust manifolds (or true shorty headers), with the stock cats/ypipe system? Anyone break 400rwhp?

niphilli

I was thinking that Joe at JPR worked a couple of packages like this in the high 300s cant remember any specifics.

Bout'ItZ28

iTrader: (19)

there was a guy in houston (screen name AAron) dynoed 400 rwhp with st2 gtp heads and the original hammar cam 222/222 .566/.566 112 w/ stock manifolds and ypipe through loudmouth exhaust. it was a 2001 camaro manual tranny

99 Black Bird T/A

iTrader: (4)

Only heads and cam car I know that dyno'd with stock manifolds was a 99 T/A it had a 216/220 cam and made ~356rwhp. I think MORE had a few get near 380rwhp a couple of years ago.

I'd like to know the answer to this too. I'm going to be stuck with 00 manifolds on my 3rd Gen for a while.

Porting with a grinder going to help much?

SPANKY LS1

iTrader: (24)

Call Extrude Hone, they can probably do a set for you, and it would probably help out quite a bit, certainly for the $$$.

Shawn

99 Black Bird T/A

iTrader: (4)

Extrude Hone wants $625 and the body of the manifold is pretty thin and it's fairly smooth. I'm not sure the Extrude is worth the cost and I'm afraid they will crack due to the thin casting.

SPANKY LS1

iTrader: (24)

Well, damn. Maybe some "shorties" would fit in there, since they aren't much more "space consuming" than manifolds. (?)

99 Black Bird T/A

iTrader: (4)

East Side Performance has a nice set of BBK 1 3/4 primary shorties. I talked with Guy and we weren't sure if the BBK would fit or not in my 91 RS with an LS1.

Terry I think the new BBK 1 3/4 would be the best of the shorties.

JoSeY

why spend thousands on a H/C package when you can do a nice cam and Longtubes for probably less and be VERY close to the 400 mark....just doesn't make sense to me...explain why u want the stock cats...??Street racing or something????

jrp

iTrader: (16)

i agree, i can understand people doing conversions and swaps where LT's wont fit but on a 4th gen fbody i dont see why you'd spend 2k+ on h/c and choke them off with stock manifolds.

niphilli

If you are going with stock manifolds make sure they are '01+.

I think I remember you bought a vette, if so go with an '02+ Z06 full exhaust (manifolds X & catback) their cats and catback would be your best bet for making good power with a "stock" exhaust system.

Ragtop 99

iTrader: (7)

Why use stock manifolds:

1) Not that CA emissions have stopped Terry in the past, CA has a reputation of enforcing the visual inspection and long tube headers are illegal for on road use (even if you can pass the sniffer) because you have tampered with emissions control equipment.
2) Headers are noisey compared to stock manifolds.

jmX

Like I said on the other forum, I made 393rwhp through stock exhaustmanifolds, stock cats, and stock mufflers.

Mods were Thunder Racing (GTP) heads, TR227/224 cam, ASP pulley, and 2001+ intake manifold.

Reasons not to use headers....they make the car sound like **** (in the engine bay, under the car, etc)...rattling, exhaust pulses seem to be noisey, they aren't legal in CA, they scrape on lowered cars. The stock exhaust setup sounds oh so smooth, OEM, no leaking/rattling/pulsing noises.

niphilli

I completely agree. IMHO headers do not mix with C5s because of the reasons you mention. Did you make that power through stock pre-01 manifolds?

Cal

iTrader: (1)

I kinda like that exhaust pulsing noise through the headers . . . brings back fond memories of my hot roding days as a 20 year-old with my '67 Firebird.

Damian

iTrader: (89)

A friend of mine made 413 RWHP through stock manifolds...

TEA 1.5's, TSP 231/237 cam


Josh

jmX

niphilli, it was on my 99 with the stock exhaust manifolds.

Damian, did he have stock cats in place and stock mufflers, or what was the setup?

TTopJohn

Headers are noiser, more likely to cause exhaust leaks, and don't fit as well as stock manifolds.

It seems that just about every long tube out there either hits the floorboard (and requires a BFH or some heater hose to fix - both a bit ghetto in my opinion) or it scrapes on all but perfect roads. Or it reduces clearance to get to the oil filter and oil drain plug. And all these packaging issues are even worse if you want to add cats on the back of the long tubes.

It all depends on what you want from the car.
You could do a cam only car and get very close to the 400rwhp mark.
You could do heads and cam and get very close to hte 400rwhp mark.
You could do a 383 and get very close to the 400rwhp mark.

But the cam only car would feel very different from the 383 car.
Think huge cam, duals that dump before the axles, and 400rwhp vs. mild cam, ported heads, more cubes, and an exhaust all the way out the back through cats and mufflers and 400rwhp.
One is great for a weekend toy, but it might get on your nerves if you drove it every day or took it on a 500 mile trip. The other is a more relaxed grand touring vehicle that can still haul *** if need be, but doesn't sacrifice any of the car's daily drivability and NVH characteristics.