theMOSTWANTED

Hey guys I'm new to these cars I recently sold one of my Grand Nationals and figured I'll try one of these out. I found a 99 z28 for $3700. It has SS hood and spoiler, hooker long tube headers and a slp loudmouth exhaust. What are some good mods to start off with on these car. I just found out that the 99 z28 has the 5.7 motor. Is there any advantage to having this year. I have 5.3 motor from a 2000 silverado are the heads worth having some port work done to them and switching them out. I was also thinking about a Ls6 intake, cam(not sure of what grind whats recommended something with a nice lope to it but streetable)torque convertor( not sure on stall) and gear for rear end 3:73 or 3:90 or 4:10????????? I'm so excited about this new project. I don't know where to begin. Any help and incite is well appreciated.

Injuneer

Welcome to CamaroZ28.com ! ! !

I'll "copy" your post to the LS1 Based Engine Tech forum where you are more likely to get the info you are looking for.

theMOSTWANTED

I guess this one of those sites where you can't get any feed back. Come on guys theres got to be somebody out there that can help me out here!!!!!!!!!!!!

theMOSTWANTED

This is one BS forum. Can't get any help or maybe I'm just on the wrong forum. This is a shame so many views and no responses. I must admit the turbo buick guys are alot my friendly and certainly helpful. Sorry if I offended anyone but this sad. Can someone please direct me to a better forum for ls1 camaros.

DANOZ28

if you get a stall for your A4 you could go with a slightly bigger cam. the stock weakspot are the valve springs. flip your air lid to see if its aftermarket. open & smooth vs plastic baffles. do you get any wheelhop? if yes think about sfc subframe connectors; lca's lower control arms & panhard bar.(for traction). i think a tr224 is a great medium cam for drivability. a nice set of ls6 cast# 243 heads ported w good valve springs will really get ya going. an old article from high perf chevy "ls1 do's & donts" is worth finding. cheers! ps you need a good tune after adding performance parts. A/F should be around 13:1.

theMOSTWANTED

Thanks alot DANOZ28!! Thats some good info. What mods you think I should tackle first. Give by order. I already have headers and exhaust which I will change to true duals cause I hate the way the slp loudmouth exhaust sound. I believe everything else is pretty much stock. It just seems like my exhaust is hurting my performance some how. Its like when I'm going 55-60 mph and get down on it. It seems to choke out and not respond it doesn't sputter or anything like that it just fall flat and the RPMs come up real slow. What could this be?

Injuneer

Since we have disappointed you so badly.... try LS1Tech.com

Some of our forums are more active than others. LS1 Based Engine Tech is not one of them.

theMOSTWANTED

Well the thing was I see there are views and no one responds its kind of a blow off. I know I look throughout forums in the tech sessions and if someone has a problem that I encountered I gladly give my input on the situation. And I have joined ls1tech.com. But when DANOZ28 gave some input it kind of changed my views about the forum. I have a new toy to play with I'm trying to get this thing as quick as my Grand National.

theMOSTWANTED

What exactly do you mean by wheel hop? I think I kind of know what you are talking about I think that answer is yes. I think I will start there with a few supension mods.

Injuneer

In defense of the many fine members we have on this site, I'd like to put this in perspective.

You posted this on the "New Member Intro" forum on 1/12 at 3:13PM. On 1/13 at 9:56AM I welcomed you, and explained that you would be more likely to get help on the LS1 Based Engine Tech forum, and I took my time to copy your post to this forum.

55 of the "views" were of your post on the "New Member Intro" forum, and it is very unlikely you would get much in the way of tech help on that forum. When I copied your post here, I knew there is somewhat limited traffic on this forum, but also knew that while it may take a while for the right people to read your post, they would be able to help you. What surprises me is that in less than 5 hours of me moving the post, you started the angry criticisms of the site. I suspect that the people who viewed that criticism chose not to respond.

I would suggest that you divide your tech questions into manageable packages, and post them on the correct forums. This is for "engine" questions. There is a "Suspension, Chassis and Brakes" forum, a "Drivetrain" forum, etc. The commonality of the 4th Gen (93-02) F-Bodys means that you will get some excellent help on each of these forums, IF you are patient and wait for the right people to read your posts. For example, I know the LT1 engine inside and out - I can tell you how to make 1,000+HP - but I know little about the LS1 engine. But because all of the 4th Gens use the same suspension, I can help you with that area. My knowledge of the 5.3L LSx derivative is limited to owning a 2001 Silverado, and knowing that was what was under the hood.

We are here to help and willing to help. But I would request that you be patient.

JakeRobb

Hi,

I too own an LS1 camaro and a Grand National.

The neat thing about the GN forums is that nearly everyone there has the same car. Anyone planning on doing any mods at all generally has the same plans (drag racing), so it's easy to find someone with an opinion or suggestions for you.

Here, we have a different neat thing. Members here are people with any of five generations of Camaros (or none at all), with several different varieties of plans (drag racing, autocross, show car, road racing, top speed, etc), so lots of people check out your thread who might have no idea how to go about modding an LS1 car. All you said in your subject line was that you got a 99 Z, so maybe people are coming in to see if there are pictures?

Anyway, there are still a handful of LS1-oriented gearheads around here that are willing to help out where we can. Please try not to alienate us with stuff like posts #3 and #4.


Now, on to your question:

All 1993-2002 Z28s and SS's have a 5.7L V8, but '93-'97 have the Gen2 LT1 motor, and '98-02 have the Gen3 LS1 motor. These engines are quite different from each other (and from the Gen1 350ci small-block Chevy), so I wanted to clarify.

'99 is a fine year; the LS1 is an excellent platform in all of its variations. For the most part, all LS1s are the same, but there are some year-to-year variations. Off the top of my head:

'98-00 has a slightly more aggressive cam than '01-02
'01-02 has the LS6 intake manifold which more than makes up for the cam

As a result of those two changes, '01+ cars get 5 extra horsepower, and the ones with manual transmissions lug less at very low RPM.

There were several other changes for 2001, but most of them won't matter to you. If you're curious: http://www.c5racer.com/wordpress/200...1-2002-changes

You could certainly do that, or you could do the work to your LS1 heads directly. Your LS1 heads are a 241 casting:

Combustion Chamber Volume: 66.67cc
Compression Ratio: 10.1:1
Intake Port Volume: 200cc
Exhaust Port Volume: 70cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches

The 5.3 motor is an LM7, which uses either a 706 casting:
Combustion Chamber Volume: 61.15cc
Compression Ratio: 9.5:1
Intake Port Volume: 200cc
Exhaust Port Volume: 70cc
Intake Valve Diameter: 1.89 inches
Exhaust Valve Diameter: 1.55 inches

So you'd be starting farther behind with the LM7 heads, but you could certainly work them over enough to outperform the stock LS1 heads. Both are a quality aluminum casting with to begin with, and both use cathedral intake ports, so you shouldn't have any compatibility issues. This is totally up to you.

The LS6 intake is a fine piece. As I said above, GM started including it stock on 2001+ LS1 cars. There are also aftermarket intake upgrades. Depending on your budget and power goals, you might want to consider spending more on something the like FAST's composite intake.

This is entirely dependent on your goals. Are you building a fun-on-the-street car, a drag car, a street-strip combo, or something else altogether? Do you need it to get decent gas mileage, or is 4mpg going to be fine?

In general, stalls in the 3000-3500 range are pretty popular on LS1 cars. I'm a manual transmission guy myself, so you'll probably want to get advice from someone else on this one.

Again, this depends on your goals and needs. 3.73 is the most popular choice for auto guys; manual guys tend to go 4.10.

Get an airbox lid.

SLP Air-Box Lid, 1998-1999 V8 Camaro/Firebird SLP PT# 21044 [21044] - $99.95$89.96 : MarylandSpeed.com- Your First Stop on the Way to Performance!

After that, you need subframe connectors. EVERYONE with a 4th gen (that's '93-02) needs subframe connectors. Some people will tell you they got them and didn't notice a difference; these are people who installed them early in the car's life. The longer you wait to get them, the more desperately your car will need them and the more you will appreciate having them, but trust me: you need them.

After that, suspension. Shocks, springs, and the various arms and bars. The exact details depend on your plans.

It's not likely your exhaust, although you might have a clogged catalytic converter. Is the Service Engine Soon light on? If so, there will be a diagnostic code that can help troubleshoot.

There are lots of things that could cause those symptoms. I'd take the car to a reputable mechanic (not the dealer) for a diagnosis.

theMOSTWANTED

Sorry guys I didnt mean to bash the site for that I apologize. I do need to be more patient. I just got the vehicle and just kind of excited about the car. I may be comparing it to the GNs responsive accellerator. I just want to get the car up to my standards and quick. I just want a nice street/strip car I'm not to concerned about gas mileage at the moment but I don't need a gas guzzler either. I don't think the car has cats on it and I took it to Auto Zone to get the SES light read it had about 8 codes to show up. I'm going to go have it tuned since it probaly never had one since the LT headers. JakeRobb thanks man you were really helpful and gave some nice pointers. Subframe connectors are first on the list after the tune. I'm going to do a full tune up this weekend spark plugs and wires and sea foam the the car.

Injuneer

Post the codes. I can help you with those.

DANOZ28

wheel hop is when you do a burnout and it feels like a tire is bouncing losing traction from all the movement in the rearend & chassis. my convertible use to boat rock & a little wheel hop before i added sfc's & lca's. typical first mods are air lid & exhaust catback which you have, next check if you have cold air induction or free ram air. since you have headers next step imo would be sfc's & lca's. better tires if needed after that some say stall, some gears, i went with heads , cam & ls6 intake. up 2 you & your budget. cheers. ps on the stock 99 intake if you look in the throat of the throttle body & see a silver thing hanging down there is an easy mod to cut that obstruction out.

theMOSTWANTED

Yeh the car does have wheel hop. I will be doing the free ram air mod this weekend. I believe the egr mod has been done I have to dbl check I don't remember seeing it when I cleaned the TB with TB cleaner. I will get an air lid next then do sfc and lca.