MannyZ28

iTrader: (1)

I have a 98 Z28 which I bought new, and it's been pretty much babied it's whole life. Never been to the track, has gotten Mobil 1 since the 3000 mile mark, never did donuts with it, never hit the rev limiter.

I have some basic bolt ons:
Stainless Works Headers with 2.5" Y pipe
TR224 112 LSA cam
LS6 intake
918 springs
TR hardenend pushrods
Taylor 10.4 mm wires
ASP pulley
B&B Triflo exhaust
QTP cutout
NGK TR55IX plugs
LS6 ported oil pump
Katech timing chain
BMR LCA's
SLP SFC's
UMI double adjustable dual rod ended PHB
Spohn adjustable body mounted torque arm with longer bolts
uh....and yeah....Direct flow lid

....all of which I just did coz I wanted it to sound mean, and so I can put something in my signature....

ANYWAYS:

I heard that the 98 cars have weaker rod bolts. When exactly does that come into play? Only when you drive the car hard and rev it high, or is it a factor just because the car makes more power now?

Also, I do want to get heads now....probably the PRC Stage 2.5 from Texas Speed, but if I rememeber correctly, the 98 cars have a different head bolt pattern than the 99 and up, and new heads all use the 99 and up pattern, right? Would I have to just order a new stock 99+ valve cover then, and is the dealer the only place to get those?

Thanks!

Manny

Studytime

iTrader: (15)

Rod bolts aren't that huge of an issue, but you're right it would be a concern at high RPM. Judging by how you described the car, I wouldn't worry about it in your case.

Yes, you would need to grab some center-bolt valve covers and coil pack brackets. You can get the brackets from the dealer for cheap, and the valve covers from a wrecked car/ this board/ other /etc. Those should be easy to find.

Ben Theriot.

MannyZ28

iTrader: (1)

I almost don't want to know how much new valve covers are....but...call me weird, I just don't want to put used parts on my car...especially a wrecked one..might transfer bad karma or something...hehe

Studytime

iTrader: (15)

You might very well be able to get some new OEM GM ones. Do you order parts fom GMpartsdirect.com?

Ben T.

MannyZ28

iTrader: (1)

Yeah I am going to have the check prices there.

ls2 bait

iTrader: (11)

i changed the rod bolts in my 99 but i routinely shift at 6800-6900. and i do mean routinely

NC98Z

iTrader: (1)

I would recommend changing your rod bolts in a 98. It is definately cheaper than a new shortblock. When I started modding my 98 I had trouble with the rev limiter because the damn engine turns up so much quicker its hard to adjust the cpu to compensate for it. I've spun rod bearings on 2 different motors so far all built by GM. And when you add thoses TSP 2.5s your gonna pickup about 50+ hp and things are gonna happen alot quicker. Just remember a stock tach can't keep up with a LS1 at WOT.

gun5l1ng3r

^Would you say that you spun the rod bearings right after you changed the Rod Bolts?

MannyZ28

iTrader: (1)

Hmm...what all is involved in changing them? Sounds like a tricky operation. I am extrememly easy on my car. I am just doing these mods for the sound, and just to be able to say "yeah, it has that much power".

david vericker

iTrader: (1)

This whole deal sounds like a total waste of money to me. Obviously you must have some fear when it relates to HP - only talking about the damm thing making XXX power is just plain stupid. Buy a VW and take the muffler off and that should satisify your need for sound. Yeah, 98 LS1 motors with (modifications) should have their rod bolts upgraded, but in your case it won't be necessary - all blow and no go.

mvvette97

iTrader: (18)

I wouldn't worry about it. My 97 vette has the so called weak rod bolts. It has about 57k on it now. If you don't plan on reving the **** out of it then don't worry about it. I'm not going to worry about mine since I don't ever over rev it. I think the rod bolt failures are because of people reving the engine past the limits of the bolts.

Blk97WS6

iTrader: (19)

80,000 miles here and still have the original rob-bolts as well. Like said before, you should be fine with the stockers. With that cam your powerband is starting to drop off around 6200rpm anyway, so theres no need to rev any higher.

MannyZ28

iTrader: (1)

Different strokes for different folks. My car already sounds mean as hell being that it has a cam, headers and a cutout. 375 rwhp isn't exactly no go. I do like to get on it once in a while...but I don't go crazy and don't want to take it to the track either, coz I know I'll break something if I do. Besides, with my current tires (Yokohama AVS Sport) I have no traction (eventhough they're 315's and I have all the traction enhancing suspension mods). I'd rather not loose my car in some stupid street race, I don't want to abuse it on the track, which is why I went with a smaller cam and probably not very aggressive heads instead of all out go fast parts. I just like intimidating people on the street and let the car speak for itself. You might call me a magazine or "dyno sheet racer", but so what...it's fun to me. I just feel that heads will complete my engine modifications, it feels incomplete the way it is to me right now.

GR33N GoblinM6

iTrader: (14)

113k on my all original 98 motor.. still the same heads and everything..

i take mine to just before 6krpm because i feel the tach moves slower than what it shows..

LS1Formulation

iTrader: (13)

I have a '98 with 140K on it and I am installing the exact same cam soon along with LTs. I am not going to spin it over 6300 RPM so I'm confident it will stay together. When I do a heads/cam package later this year, I am going to upgrade to Katech rod bolts. Honestly, with how well taken care of your car has been, I wouldn't worry about it.

2 Stroke Racer

iTrader: (11)

I spun a rod bearing in my 98 with less mod's and 50k. I have a 99 motor now. Has anyone changed rod bolt's with the engine in the car??

85ta383

iTrader: (18)

it isnt bad doing rod bolts in the car! there is write up on it ( a recent one too)

there is a thread on this site for the spun rod bearing club.. i think if you regularly spin your motor to high rpm's....98 or any other year.... you can pretty much count on rod bolt failure.

so if your gonna see past 6600 regularly change em out. if your just a "recreational driver" i think you will be fine.

my 98 has 88000 on it, still in one piece!!