Stay away from 1998 models? Help
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TECH Apprentice
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From: North Alabama
Stay away from 1998 models? Help Hey guys I have possible found a 98 z that I like but someone one here told me to stay aways because the heads on 1998s are no good. Is this true?
Thanks
Thanks
The heads are the same other then a casting number and the valve cover bolt pattern. They may flow a few cfm less then like a 241 casting that comes on the 01-02 models, but no there is no "problems" with the 98 heads.
I love my 98. Yeah I'm disappointed when I hear of some of the advances the newer models have, but it's not enough for me to sell it and buy a newer model. I'm making 400+ horses with no problems and stock heads 
On The Tree
Joined: Dec 2001
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From: Bethel, CT
'98s also have a stainless exhaust manifold which was replaced with a cast iron unit with slightly better flow. Later models replaced the intake with an LS6; again; slightly better flow.
'98s also have EGR, bigger injectors and a slightly bigger cam.
'98s also have EGR, bigger injectors and a slightly bigger cam.
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my 98m6 with full bolt ons ran 11.96 @ 113mph last year with a bad T56. they really arent much "crappier" than the 01-02's. That was also my second stock LS1 engine. The original one blew up at 57,000 miles almost 3yrs ago. That was before i did some research and found that 98 models can have weak connecting rod bolts and oil pump issues. It just let loose on me one day. After i stopped the car and walked out to see any damage, i felt like i was going to vomit. it happened to a few other people that i know too. but you could fix that with some ARP rod bolts and a better oil pump. i must say i am happy with this motor now.
My 98 blown had 407hp/406tq with 5 psi and stock heads and cam. Made 317 pre blower. VMP Tuning had ZERO issues tuning the stock PCM. He said it is a little more work because you can not tune live, but he shrugged it off, and nailed it perfect in 4 pulls.
Car now has LS6 intake, TR Blower cam, and 6.5-7 psi. Tune and numbers as soon as Justin and I can get together!
Car now has LS6 intake, TR Blower cam, and 6.5-7 psi. Tune and numbers as soon as Justin and I can get together!
I've had my '98 for about a month now and I love it. For a damn near stock car that's a decade old, it runs like hell! There is really no good reason, that I can think of, why NOT to buy one just because it's a 1998.
They're nice cars and whatever little "setbacks" they have shouldn't deter you from buying one. They can be had for dirt cheap compared to later models and run just as good.
Don't be scurred, just get one and prove your buddy wrong
They're nice cars and whatever little "setbacks" they have shouldn't deter you from buying one. They can be had for dirt cheap compared to later models and run just as good.
Don't be scurred, just get one and prove your buddy wrong
Dont forget the good reasons why you should get a 98, the fuel pump is easier to change, the temp gauge works, bigger cam, bigger injectors. If you dont plan on modding your car go for an 01-02. If you turn your own wrenches, a 98 is great, your going to replace all the disadvantages in the first few months (Intake/headers/!egr !air) and then running faster than an 01-02 and have less money in it. When I look for fbodys i look for the mechanical condition not so much year. I looked at a 01 a few 99's and then I decided on the 98 I just got.
my C5 is a '98 and the only thing i have a problem with is that year didn't have HUD
lol otherwise the engine doesn't worry me. I'm doing heads, cam, LT's, LS6 intake and a tune. the only thing i've heard about the '98s are the rod bolts aren't as strong. but i've heard it's hit or miss with them~Cole~
lol otherwise the engine doesn't worry me. I'm doing heads, cam, LT's, LS6 intake and a tune. the only thing i've heard about the '98s are the rod bolts aren't as strong. but i've heard it's hit or miss with them~Cole~ 
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98's are fine cars, mine's doing the HP and torque in the sig with a cam. Pre cam with only bolt ons I hit 360ft/lb and 350HP. Who says 98 heads don't flow "well"? they just don't flow well compared to 01-02 or LS6 heads, but they still are LS1 heads which put themselves in a league of their own.
98's were just like the 93's similar other model years but different. Will it make or break you? No.
BUT I having worked on a 93 and then a 94 AND 96 LT1's the later models were FAR much easier to mod and work on. and the same thing with the 98 and my 2002, a world of diff. and STOCK for STOCK the 02's put down more power, be it from the intake or the factory tune, or the cam who knows.
IF you can go newer, lower milage, do it but if you cant then dont worry. A LS1 is a LS1
BUT I having worked on a 93 and then a 94 AND 96 LT1's the later models were FAR much easier to mod and work on. and the same thing with the 98 and my 2002, a world of diff. and STOCK for STOCK the 02's put down more power, be it from the intake or the factory tune, or the cam who knows.
IF you can go newer, lower milage, do it but if you cant then dont worry. A LS1 is a LS1
FYI I always heard rumors that they are not as prone to piston slap. You also get a functioning temp guage and 28 lb injectors. I have had both and I can't tell a difference. My 02 had a G5 cam, and my 98 has yet to be cammed. Probably going with the F11 cam and some stage 1 ported 806 heads ported by me, myself, and I. My 02 dynod 330 RW with a lid, ported tb, and wide open borla. Guessing my SS is in the vacinity of 340 rw with the LT's, guessing that is.