flowrider

iTrader: (9)

Yep, I'm very serious. It's tough for me to believe that folks are buying into this. the reasons behind my statements are:

1. From my observation the stock cats are not that tightly packed.

2. I have a local friend who has a PPE equipped ISF with JoeZ exhaust and no cats. My F has PPE headers and PPE exhaust equipped with Magnaflow cats. When both cars were dynoed, there was a difference of less than 8 WHP between the two. Mine was run with the PPE exhaust valve open.

3. Someone else's dyno, see below shows the following:

Add a JoeZ exhaust (no secondary cats) - Get 20 WHP
Add Sikky Headers (no cats) - Get 34 More WHP

4. So with the above information we can postulate. Let's assume that since my cats are HighFlow, and reduce the total WHP by 8, I would guess that the stock cats, at the very most, reduce the WHP by Let's say 15. The secondaries, probably the same amount. So let's say, total loss in HP by having all four cats in place is 30 RWHP. And, I think I'm being very generous.

If the above is true, Than we can estimate a stock exhaust system, with no cats produces something like 360 WHP. Chart #1 that I have attached shows a top of 385 WHP with Sikkys and JoeZ. So headers are good for at least 25 WHP. But. The two cars listed in my point No. 2 above, produce 392 WHP with HighFlow Cats and 399 WHP with no cats, chart #2.

What all this shows me, is that at the very least headers are worth at least 25 to 35 WHP.

Now, all I have shown and said, are from different runs by different people with different cars at different times on the same type of dyno.

You folks all talking about anecdotal results of three cars and butt dynos.

I have spent way more time explaining myself here, and I really have no vested interest. My car is set up the way I want, and it's staying that way. You folks are free to believe anything you please, and so am I. Am I "One Way"? I really don't think so

Lou

lobuxracer

iTrader: (2)

If you want to impress your friends with dyno charts, knock yourself out. I don't care about dyno charts. When two cars of similar manufacture run side by side and neither walks away, it says a lot about the evenness of the match up. Weather/altitude is not a factor. The size of the fan blowing into the front of the engine isn't a factor. The methodology of loading the engine isn't a factor. The hood being open or closed isn't a factor. In fact, I couldn't care less what my car shows on a dyno. I only care about it being faster than before I spent any money. Witness the K&N intake dyno which no one has translated into a quicker/faster time slip. If the engine makes similar power with gutted cats as it does with headers (of any manufacture), then the header design is inconsequential and the Lexus design is far better than many give it credit for being.

I already know all the theory. I know primary size and length numbers, I know 4 - 2 - 1 is a better header for a lot of reasons, I know collector construction means a great deal to flow numbers, and I know Burns Stainless provides some of the best stuff in the industry. It's handy to know stuff.

I also know everything I thought I knew about porting went out the window when I learned fundamental gas behavior, and even more went out the window after looking at what some of the real pioneers are doing. So, I'm not at all convinced the car isn't competitively fast with just gutted cats.

flowrider

iTrader: (9)

Darnit Lance, I'm trying to impress no one, least of all you. The automotive knowledge you have is vastly superior to mine. But I do have a little knowledge, and I am allowed to have an opinion that is sometimes contrary to yours. I was called out by a fellow forum member, I was just trying to explain myself. If you don't or can't understand what I'm trying to say, so be it. But, don't cast aspersions on me.

All the Speed Shops that I know of spend thousands of dollars on Dynos. Manufacturers of automobiles spend thousands on Dynos and Wind Tunnels. All the Race teams I am aware of spend thousands on Dynos and Wind Tunnels. If you choose not to recognize them, that's your prerogative, but don't put me down when I disagree with what you have to say, and I back it up with facts.

Lou

lobuxracer

iTrader: (2)

An engine dyno and a chassis dyno are two different animals. The manufacturers spend millions on a single dyno, and the results they get are repeatable. Speed shop dynos are not even in the same ballpark. They have so many parameters they can't even begin to manage, much less control, so what you see from them is always suspect. Especially when you're looking at small differences (under 2%)

Nobody ever gets called out on CL. You tell yourself someone is calling you out. This is the Internet after all, no one's opinion carries any weight here. Believe me, I can find plenty of posts in reply to things I've said casting great aspersions on my intelligence. I just take it for what it's worth. It's another person's opinion who has never met me, doesn't know what I've done, and doesn't care. I focus on the doesn't care piece, because I do my best to reflect this same attitude. It saves me a lot of angst.

VtotheJ

iTrader: (2)

Gotta agree with Lance. There are a ton of factors going into a dyno. Nothing beats running the SAME two cars side by side with drivers with very similar skill with DIFFERENT mods so we can compare.

4everkidd

iTrader: (2)

What would be the best way to go about doing this while keeping the stock headers on the car?

Large gauge drill and shop vac?

ICEBERGS

im def all ears and eager to hear or rather see the findings........Im all over this if this is an easy mod and no CEL issues....A write up should def follow the results....

tgui

4everkidd

iTrader: (2)

There will absolutely be a CEL.

Need either a PPE or Sikky O2 conditioner

jkappel

it would probably just be more worth it to buy a totally new set of headers. if not then hollow out the cats and put fowelers on the sensors, should aid in avoiding a CEL

DCoolBeans

Lou, I enjoy this forum as much as you do. I love reading everybodys story here. You have been here for a while too and I have always been cool with you.
With that being said I never called you out. I just said you were thinking one sided.
I'm not telling people here to sell their Sikky or PPE headers or their Catbacks . I'm sharing my experience with you and this forum. I am not gaining anything from this. Its pretty straight forward what I wrote. We swapped cars, raced em. Data logged them to make sure they were running fine. We got back into our own cars and raced again. His car felt just as strong as mine. We did a rolling 40mph race so take offs would be on point.

Remember K&N's dyno, saying they gained 40 whp on an intake alone?

I wrote the details on my first post on the first page. They can either cut up out and replace with straight pipes or gut them out. You will need a 02 conditioner like PPE's

DCoolBeans

Oh ps I miss the sound on my old straight pipes
Imo, MrSlays car sounded way better than mine

Vervish

iTrader: (4)

Sweet - this can be done with the header still installed?

ISFPOWER

iTrader: (20)

is there enough room to cut and replace with straight pipes while headers are on teh car? sorry too lazy to look underneath right now.

jdm_altzza

iTrader: (9)

Yes, this is an option and can be done if you do not want to gut your cats.