Manifolds vs. Headers

**david_viny** · 09-28-2008, 10:52 AM

How much power would I be losing if I were to put a decent cam in my car and some bolt on’s with my stock exhaust manifolds and cats? If it’s like 10-15 hp I could maybe deal with it but if it’s something like 30+ I might just have to do it lol.

Also didnt the 2001-02 factory manifolds have a slightly better design then previous years?

Anyone else running a fairly big cam with stock manifolds and cats care to share their power #’s?

Thanks,
-Dave

**WS6ICK2K** · 09-28-2008, 11:07 AM

The 2001 - 2002 cam with a factory LS6 style intake. It bumped up the hp up about 10.

IMO I would def do LT headers with a cam. The headers really help out the cam plus it sounds so much better. Lts are one of the best bolt ons to do.

**Bouvers** · 09-28-2008, 12:53 PM

I don't know if you're doing heads or not with your cam but if you are don't even think of doing that without doing LT's...

if you're doing cam only I still dont see the use of doing without doing LT's you can get a good pair of LT for the price of your cam... consider as just part of "must do's" for a cam, such as springs, retainers and what not.

EDIT: yes the 01-02 came with the LS6 however, the initial post was inquiring about exhaust manifolds, in which case yes in 01-02 the LS1's did receive slightly better flowing exhaust manifolds but not nearly significant enough to make up for LT's...

**Hi-Po** · 09-28-2008, 03:27 PM

If you dont have the money for LT in your cam budget, dont buy a cam. LT's should be your first mod. Bar none IMO.

**0verkill** · 09-28-2008, 03:46 PM

i know that llt's are a good bolt on but i know you cant have them in some places. my wife and i may move to so-cal and i know you cant there so is a cam posabil with just manafolds?

**Mr. Luos** · 09-28-2008, 04:07 PM

There are cams out there designed to work well with the stock exhaust manifolds.
You are leaving power on the table regardless though.

If you get a basic off-the-shelf cam NOT designed for stock manifolds (cheater type cams, I think Thunder called theirs the CheaTR), you will be leaving at least 30 HP on the table with the stock manifolds.

**david_viny** · 09-28-2008, 05:21 PM

Damn, looks like I should do Lt headers then when I do the cam.

I'm not very close yet on what I want to do as far as cam, possible head porting or anything of that nature but right now an exhaust is def on the list as far as cat backs go. I was reaaaaally looking at the Bassani true dual but I think there headers are like mid length ones (almost not worth it) and would really not want to hack up that exhaust for Lt's. So I was going to get the Bassani that goes to the stock manifolds & cats if they flowed ok after the future mods. Just trying to think ahead, would rather do the exhaust just once.

We have a visual inspection on a lift in Maine so it def has to have cats (at least for inspection

) but I’m not 100% if the Lt's would pass, even if there were cats.

As far as the 01-02 manifolds I meant exhaust, should have clarified.

I would still kind of like to see a dyno sheet though on how much power I would be down with factory manifolds and cats, but I guess no one keeps them after a cam change lol.

So now I'm back to confused

**LT1 > LS1** · 09-28-2008, 05:26 PM

just forget about the cam for now. you need supporting mods for that first.

I vote longtubes. I just ordered a set for my car. check this place out!!!!!!!!!!!!

www.lpparts.com

**Bouvers** · 09-28-2008, 08:14 PM

I'm sorry I know nothing of the laws so I'm sorry if this is a stupid question but just something worth mentioning you can get LT's with full EGR & AIR hook ups... or atleast I thought you could...

**0verkill** · 09-29-2008, 08:40 AM

Originally Posted by Bouvers

I'm sorry I know nothing of the laws so I'm sorry if this is a stupid question but just something worth mentioning you can get LT's with full EGR & AIR hook ups... or atleast I thought you could...

you can but in sum states like cali i know you have to have the cats in the stock lo-cal to pass

**chuckie669** · 09-29-2008, 09:01 AM

Originally Posted by LT1 > LS1

just forget about the cam for now. you need supporting mods for that first.

I vote longtubes. I just ordered a set for my car. check this place out!!!!!!!!!!!!

www.lpparts.com

Let me know how those look/ work out when you get them in and installed. Never heard of that place, but their prices are pretty good.

**LT1 > LS1** · 09-29-2008, 01:05 PM

hopefully will arrive tomorrow. I have heard absolutely NOTHING bad about em

**BlueMagicSS** · 09-29-2008, 01:20 PM

Definitely get LT's before a cam... no question. LT's should be one of the first things you do next to the free mods (which I still have to do)

LT's are a big no-no in California... BUT I have them with no cats.... oh well... there are ways to pass smog... so I mean hey... it's completely up to the owner... you MAY be able to find some shorty's that are legal, and if you seach HARD ENOUGH MAYBE some LT's too... my Edelbrocks came with a CARB sticker... so if I had cats I'd "technically" be legal...

**INMY01TA** · 09-29-2008, 02:56 PM

You'd prolly gain just as much by getting long tubes now as opposed to getting a cam w/out long tubes now.

**WS6ICK2K** · 09-29-2008, 06:23 PM

Originally Posted by INMY01TA

You'd prolly gain just as much by getting long tubes now as opposed to getting a cam w/out long tubes now.

+ 1

**Blackout01** · 09-29-2008, 08:14 PM

You can also get high flow cats if you need them for inspection. I don't have to worry about emissions (or inspections for that matter hehe) so I order all my stuff completely illegal

PS LT's with ORY and Borla adjustable exaust, absolutely loooove the sound! however it is a bit loud. Basicly if I take the restrictor plate out of the tips of the borla its straight piped. I'm almost affraid of putting a cam in it now because it will be ridicuously loud. I won't be able to start it without waking ppl up lol