Why no moderator LOCK on this type of topic? The mere mention of street racing or unlawful driving gets hammered fast. The removal of cats on the street is probably a felony.

 

That would be incredibly lame

 

Just a heads up, most guys port the ls6/243 castings, they are a little stronger and can take the porting form what I hear. Very few do anything with the ls1's except make door stops.

Do some searches, there is some decent threads on head here, but more info on ls1tech.com. I think valve size will be effected by cam duration, and the rpms you want to spin at.

 

I've got ported ls1 heads(241s). I agree though, most go with the 243s and if I were to do it over again I would have spent the extra money and went with the 243s just cause I want every last HP I can get. But good results can be had with the 241s.

 

yes most of this forum is getting that way... omg he took his cats off!! call the cops!!!! omg some one talked about street racing!!! Ban HIM..

 

MAX, seriously an erection from exhaust smell, I hate to see what a woman would do for you...

 

I'm sorry... my comment was sarcasm taken the wrong way. I'm all for open discussion of everything here.Even dreaded street racing and kill stories.We can sort through what we want to read.

 

Aaaah, I did not pick up the sarcasm. Sadly I think there would be people that would have agreed with your comment anyways

I wouldn't mind seeing a kill section here.

 

Is this true? Someone was trying to tell me by removing my high flow cats on my AR system that it would net me something like 30 HP, I tend to think it's probably more like the 3 hp mentioned here.

 

I'd like to use my car as an example of what is possible with cats and is still legal. I put cutouts on it and with a 3" midsection barking some bass notes when I open up the cutouts small children and women cry, but I only do that at the track.

If you want to have a muscle car buy a 69 Camaro, the C5 is so much more than a muscle car. Just making it obnoxiously loud isn't going to make it a muscle car OR a race car. I guess in addition to being illegal, removing the cats for no good reason is somewhat demeaning to the car. It's a sophisticated sports car.

Just my $.02

Casper's Electronics used to make the Sims. But as you've been told, they can't anymore so you'll have to find them used, and deal with the problems that may arise from using used equipment.

 

Back to back dyno w/ kooks high flows and no cats on my H/C car showed no gain. Literally no gain.

 

Hot Wheels, im sure whoever said that "accidently" tacked on a zero. Going catless will:
1. MAYBE give you a couple hp.
2. Make exhaust sound better.
3. **** off a lot of people on this forum

And I just realized that you said removing your HIGH FLOW cats. Nah man, doubt you would see a diff. If you don't mind em, leave em.



Ah yes, thats what my friend said, that LS6 heads are better. He can get an easy 315cfm from LS1s though and with bolt-ons and proper cam make 500hp easy. So I think I will stick with them for now and pick up a set of LS6s later and really let him spend some R&D time with them. I know I should post a new thread but ONE LAST QUESTION. The casting numbers... Is there a method to the mayhem? What numbers are on what?

 

Thanks for the advice - I liked how you threw in #3
!

I see you are also in Jersey...Here's some advice back for you, when/if you do decide to go with LS2/6 heads for the better flow numbers, consider having them done at M2:

http://www.m2race.com/Contact.asp

The Ls1 heads are a 241 casting and the LS2/LS6 are 243 castings heads.

 

Thanks for the recommendation, but I'm going to have them hand ported by a friend of mine. He is a graduate of SAM, and was quite the student there. He told me to stay away from CNC porting because you will just get the same port that someone else has. He wants me to get a port better than that and he knows how..... I'll give him a shot and I will be sure to post flow numbers.

 

just talked to him, m2 is a GREAT company, apparently they do a lot of R&D designing ports for other companies. So I will also throw a recommendation in for them!!

 

This is turning into a real cat fight.....

 

It seemed to start that way, but actually, I thought it was getting quite civilized. The OP seems like a decent guy, seems like he wants what most of us here do The guy wants to try a few things, more power to him. We all like to tinker, we just wanted to try and help him to keep from wasting too much time and spend it on real mods The OP seems to be looking for knowledge and is willing to ask questions, which is great. And he is not getting too hung up when the majority opinion is opposite to his plan…

As for the LS1 heads, I'm sure if you port them you can get some good numbers. But, they may not last long. LS6's I don't think last forever with an aggressive port either. But, hey nothing lasts forever. Do some searches here on AFR, Tony likes to share his knowledge on the forum. If I get another set of heads for my LS6 it will most likely be a set of his heads. He is big on port velocity, not just flow numbers, I’m no expert but he has a great rep for making usable power.

FYI, the LS2 is the same casting number as the LS6 but the LS6 has lighter exhaust valves and better springs in stock trim. The AFRs and some others use a different head and can stand more porting and take more abuse.

If your friend loves to port, put him to work on the TB and intake manifold.

Are you a 1/4 mile guy or do you like to turn. You should take a weekend and attend a HPDE. It will allow you to find out what a Vette can really do And you'll be wearing a perma grin for days or weeks after

 

hey thanks for the info. Not sure what HPDE is?? All the cars I have built until this one have been drag cars. I wanted to get into autocross though as they just built a track nearby. And hey, thanks for stickin up for me there, im so tired of defending myself, glad someone doesn't hate my guts, lol.

 

Just keep this in mind:
"As much as you think you may know, there's always someone out there who knows more."
There are plenty of people here who take the cats off, but remember were in Jersey and they will check. Everyone gave you good advise that it's almost not worth the trouble.

HPDE stands for High Performance Driving Event, fancy way of saying Road Course.

As for the sims, I came across them yesterday at speedinc. There only for off road use though...........so promise me you won't put them on your street car.

I have a house in Ocean City, so maybe see you around.

 

I lurked this thread for a minute and I just wanted to say to you that bringing up the removal of catalytic converters is a "hot-button" issue on this forum. Sorry you felt like you were being attacked but, the guys doing the attacking are just trying to spare you the issues that you will experience for such a minimal (read: practically non-existant) gain. I think you are getting good advice on both sides of this issue. I think you should keep the cats on or go with HFs rather than going catless (the responsible thing to do if you are running your car on the street) but good luck on whatever you decide to do