andy-lswon

iTrader: (1)

I have a 98 z28 and figured this would be the place to ask about any good vs bad about a 98 compared to the last years of the 4th gens. What do you guys think. I've heard 98s have thinner cylinder walls is this true? Yeah everyone knows 01-02 had the ls6 intake but whats some internal differences of a 98?

RARON455

iTrader: (35)

The LS6 also has a better PCV system, utillizing a vent in the valley cover itself. There were also changes made to the oil galley system, I wouldnt really consider that much of an advantage, just a change that was made. The other big difference is the later models PCM is a better unit when it comes to tuning, a good tuner can make your 98 do whatever he wants, but from my understanding the tables in the later ones are easier to work with..
Mine is a highly modded 98 and I have no complaints..

andy-lswon

iTrader: (1)

Yea I've heard several people say that about the pcms. I'm gonna have full bolt ons here shortly then have it tuned to get the most out of it

moeZ28

iTrader: (7)

99+ you can tune on the fly...make changes while driving. 98 you have to stop, upload, then go again. the 98 heads were a different type of casting and people will say they are inferior, but truthfully only by like 3 hp. The ls1 intake is the biggest difference in power versus the LS6. get rid of the EGR and its huge intake restricting hose end. 98-00 actually have a slightly larger camshaft, slightly. The 98 cylinder walls are said to be thinner and can only be honed to .005" over, making the bore 3.903". I had a 98 car and motor but used a 2002 block and had it bored .010" over to 3.908"...so I know 2002 can be done to that much.

andy-lswon

iTrader: (1)

Full boltons with the ls6 intake and a tune is what I'm gonna have for now until cash allows for more so I'm not gonna be too worried about any internal motor work for a while but thanks for the info!

MyFirstLS1

iTrader: (8)

http://www.speedwaymotors.com/Book-H...V-8s,5954.html

Awesome read has tons of info. Found mine at autozone when i was getting some cleaning supplies. Tons of specs., history, and pretty pictures

FirebirdTransAm

iTrader: (3)

I can tune on the fly in my 98.

WhiteKnight '01

The 2001 and 2002 LS1's also come with the LQ4 cam from the 6.0 versus the LS1 cam in the 1998-2000 LS1 engines. The LQ4 cam makes slightly more mid range torque than the LS1 cam. The '01-'02 engines also came with slightly smaller fuel pumps than the previous LS1's, not sure how much of a difference this makes.

Socket

iTrader: (6)

From what it sounds like not much. A thinner cyl wall isn't going to affect you at all with bolt ons, and you'll probably be changing the cam as well. Just get an LS6 intake and you're set.

NHRAFORMULA00

iTrader: (2)

Mid year 2000 they changed to better Rod Bolts. Once you cam it and start spinning the motor to 7000 rpm its better to have the newer motor,or change the bolts in your 98-early 2000s.

moeZ28

iTrader: (7)

But you have to stop and upload to make the changes stay in the tune...correct? 99+ can make changes while driving and do not have the stop and upload. They can tune on the fly without another upload.

stangtrader

iTrader: (2)

I have a 98 as well. Yeah there's a few little things already mentioned. But they are not a issue in my opinion. To me having a steel gas tank with a return is a bonus. As far as the tuning portion its really not a big deal. A good tuner should have no problem with a bolt on car. I'm about to be getting my car tuned soon on the 98 pcm with a lq4 and a rearmount and I'm not concerned one bit.

mjs1012

iTrader: (36)

the 98s as far as i know have weaker rod bolts, the oil system through the block isnt as great as 99+, the 98s have a bigger cam (not by much) and 806 heads vs 853 or 241 on 99+. Op you should be fine with tuning a bolt on car as long as you have a good tuner.

butler

I believe the back block plate's oil groove isn't as wide.

gMAG

iTrader: (1)

98 idle & off-idle fuel settings are not as exacting as later years.
Not a big deal.

LS1MCSS

iTrader: (18)

98's had 28lb injectors as did 01 and 02. 99 and 00 had 26's.

LS1MCSS

iTrader: (18)

Explain how to do this. I've never heard of this before. Even with a custom operating system, I thought you had to upload the tune to make it permanant.

the_merv

iTrader: (88)

1998 you can tune on the fly..or real-time tuning, that is if you have the credits unlocked for it (from my understanding you have to unlock that, unless I read it wrong..)

Basically what you are doing is making your changes to your tables while actually driving..gather your reading in the scanner, and make the changes to your tables, save it and it drops it right into the PCM without having to upload anything..pretty much constant 2-way communication with the PCM, so to speak.

That's my understanding on it anyways..friend of mine does it to his Camaro with his HP Tuners.

I've tuned a couple 98's...some of the tables arent there that are in the later models. The '02 PCM is the most desirable, the 1999-up can be upgraded to the 2002 operating system from what I've read.

BLK95-Z

iTrader: (2)

Thats pretty much what I have done to my 98.

K&N, lid, ls6 intake, Hooker super comps and a tune it put down 344/341 through a stall. Stock motor with 108k miles

moeZ28

iTrader: (7)

the merv said it pretty well...however I am not sure if you can even do it with credits...you may be able to now, but when I had my 98 car, sold it in 2006, you still couldnt do anything to make a 98 tune on the fly like the 99+ cars. Maybe by now they have figured it out, but as far as I know they cant. I dont do tuning though, but my friend Phil, Bluecat, does dyno tuning here in Kentucky, so I am around it alot. You may be right though, they might have made it possible since I had mine. I just know for a fact 99+ cars can be made to tune on the fly...saving time and effort.

As far as 98 rod bolts go, people say they arent as good, but I had my old 98 car cammed from 89,000 miles till I pulled the motor for a build at 142,000 miles, and its rev limiter was set at 6800 and shift points at 6600 for 95% of its cammed life with no problems. I had 3 different cams in that time, and I pulled the motor because it blew a head gasket and went ahead and built a forged heads/cam/intake 347ci LS1...rod bolts held just fine...stock bearings actually looked pretty decent for 142,000 miles! So I call BS on the rod bolt thing. I have seen more 2001 cars spin bearings than 98 cars!