I was planning on doing longtubes and hotcam this summer but have come across a good deal on some NIB headers from a forum member. My question is, if I bought these headers now, and installed them with no cats and no egr, could I run it like this until summer with no tune? I will have to get a tune anyway this summer for the cam, so I want to avoid doing it twice. Will it turn on any lights or codes? If it does, will it hurt to run the car with these codes until mid summer?
Thanks CF!

 

Obviously I'm not an LT-1 guy, but since I think you have heated O2 sensors, you might just have to watch any leaning out. An adjustable fuel pressure regulator would help if you have that problem. I had to install heated o2 sensors for my longtubes, as the stock non-heated threw a code - it was staying in open loop, never getting hot enough. It ran good, but was sucking gas like crazy. Heated o2 solved the problem. I have an AFPR, so I can control rich-lean to some degree. The LT-1 crew will correct me if I'm off base.......

 

I ran mine with no EGR and no cats for several months without a tune. I was using an O2 sim but that should not be needed on a 95. I was told I wasted my money on it. I can't recall exactly but I may have gotten an error code once but only for a few seconds after a long drive in closed loop. My guess is you won't notice anything.

 

Being I just happen to know the person whom has them for sale and being I know that person sent you dyno sheets of what you could expect, just may be able to help some also.

Stock LTX cars from the factory run a bit rich @ WOT and being the computer reads the 02 sensors at part throttle and compensates, you will have no issues with just headers only. As usual, you can never replace a true dyno tune but that's rather expensive hp if you’re on a budget.

Been a while since I've had an OBDI computer but does your car run two 02 sensors or four? Think it’s only two; but if it’s four, you'll need the 02 simulators and it will be fine either way.

Something a lot of people miss when installing headers is you must make sure your alternator and compressor are secured in a manner close to stock to eliminate vibration. I’ll ask the person who has them for sale, but I’d bet he could show you how to do it and also how to secure your dip stick.

Cams……Hot Cam is old school. Tell the person whom you are buying the headers from what your goals are and perhaps he can help ya with that also. I’ve heard he is on his 14th LTx cam and has dyno sheets of other cams also. But I’ve only heard that.

 

Haha. I guess I should have asked you in the first place. I am leaving for a class and I'll be out at noonish. I will write up what my goals are and post em on here when I get back.

 

Alright, here is what I want.
I want to be low 13s in the quarter. I want it to be easily streetable, as in not trying to die every second. Basically what I want is as much horsepower as possible without me regretting that I got too much horsepower and it's not a daily driver anymore. I had chosen the hotcam because I have heard it's extremely streetable. I also chose it because it came in a kit with all the extras needed. I have never done a cam swap before, so simplicity is a good thing. I have pretty good mechanical knowledge and skill, so I know I can do it, and I want to learn. Do you recommend something different than the hotcam for my application?
Thanks all!
-Matt

 

I ran the tpis lt on my LT1 for a few years without a tune. Only thing it did was run on the rich side. This was without cats and with the egr still hooked up. with the tune it ran much better.

Right now the engine is stock but I will be doing cam, heads, etc. in addition to the current set up with the lt, no cats, with 4.10's.

The car is fun now and should be right where I want it when I'm done. if I can get into the low 12's high elevens I will be sound as a pound

 

Dude, look at my sig to see what I did, but I did the Hooker LTs and got rid of the EGR and CATs. I have some other stuff done as well, but with my current setup I ran 12.9 at 1,500' elev. and 100 degrees F (with street tires). I also ran that with a tune from PCMforless. When I had him burn me a program it cost me $50 so there is no reason to not get that tune. Also, if you get the tune, they will delete the post cat O2 sensor from the code, so you don't have to run sims. Also, if you are using the stock computer program, an OBDI LT1 will adjust for an AFPR within a few miles. You can also have that option with a custom tune. Just my $0.02 worth.

 

So what I have gathered here is...
If I buy the headers, bolt em on, block off the EGR holes in the block, trash the cats and weld in some straight pipes in place my car will be fine, correct?
Does my car have a post cat O2 sensor? If so, do I have to buy a simulator??? Thanks all!
-Matt

 

My car is a '94 and it had three O2 sensors; two pre-cat and one post-cat on the right. If your car is still OBDI, it will have three; if your car is OBDII then it will have four. And, I don't think your car will run right without the post-cat simulator (without getting a tune). I know that some people say that the OBDI cars that came with three 02 sensors only used the pre-cats as those were the transition years to the OBDII programming. I know my car uses an OBDII connector but has the OBDI computer. So, you might want to check and see if the car will throw codes without the post-cat sensor. I hope this helps.

 

Your car will run fine without the one post-cat o2 sensor, no codes.

 

I'm in the middle of doing my own exh upgrades, specifically in order to meet/pass emissions. ('95)

So, just to be clear.....the POST O2 is not a concern whatsoever? It could be deleted without any effect at all to the PCM?

 

YES!!

 

Thanks STL for the confirmation.

I always thought that....but it's comforting to know for certain.

 

With just the headers your car should easily run low 13's. My old 97 LT1 SS ran 13.2 @ Ennis on a hot day and current LT4 when it had just Hooker Headers and dual 3" exhaust ran a low 12.7 at the same track in better weather. One run would have been a 12.6 but I broke a 4th gear syncro. It ran a 8.19 1/8th on that pass. Sent you the dyno sheets of what it was putting out with 100% stock motor and headers.

Eventually ended up with a 306 cam, MTI heads and Hooker long tubes in my 97 SS and it drove great. Currently have a 245/248, .630/.630 custom ground on a 112 with 12.8 compression and it drives pretty much like stock. Will admit the car has had a ton of tuning for both power and drivability. (You can drive the car if you make it here)

There is a huge misconception by the public in general regarding drivability and larger cams. The only cam I had drivability issues with was a solid roller 254/263 with .680 lift. That cam did suck driveability wise plus it made no more power than one with 10 degrees less duration.

Believe it or not, I’m still a fan of the LPE 211/219 cam. Absolutely perfect drivability, great throttle response and you can’t tell the car even has a cam. My SS made over 360 rwhp with MTI heads and shorty headers. Also prefer the Comp Cams 305 over the hot cam as it drives great and make more power. The GTP 6 on a 114 is a great cam making even more power.

Lots of good choices and even better cams than listed above. One of the tricks is to put it on a 114 which smoothes out the car w/o much power loss at all if drivability is an objective.

When you buy any cam the company selling it to you basically will put together everything you would need as they have seen it a zillion times. No need to buy a hot cam just because it’s available as a kit. I’d personally rather have different rockers anyway.