C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

Thinking about replacing/rebuilding my engine...Need help!!!

Thread Tools
 
Search this Thread
 
Old Sep 30, 2007 | 02:47 PM
  #1  
The Batmobile's Avatar
The Batmobile
Thread Starter
Instructor
 
Joined: Sep 2007
Posts: 175
Likes: 1
From: Fort Worth Texas
Default Thinking about replacing/rebuilding my engine...Need help!!!

Ok, I have a completely stock 85 L-98. It has 109,xxx miles on it, and I would like to either have it rebuilt or replaced. Heres the ideas Ive come up with so far...

Plan 1:
Pull the motor, have it bored, then put it back in.

Plan 2:
Buy an already machined block that is exactly the same as original, take the stuff off of my stock block and put it on the rebuilt one, then eventually have the original block rebuilt down the road.


What do yall think I should do? Possible prices (Just to let yall know, I would have my uncle help me pull the motor and reassemble it)? Also, if I was to go buy a block that matches the original, what block matches the original 350 block, so it would fit perfect without anything else being changed. Thanks, Zak.
Reply
Old Sep 30, 2007 | 06:01 PM
  #2  
The Batmobile's Avatar
The Batmobile
Thread Starter
Instructor
 
Joined: Sep 2007
Posts: 175
Likes: 1
From: Fort Worth Texas
Default

Anyone have any ideas?
Reply
Old Sep 30, 2007 | 06:39 PM
  #3  
JLeatherman's Avatar
JLeatherman
Burning Brakes
15 Year Member
 
Joined: Sep 2006
Posts: 1,202
Likes: 3
From: MD
Default

Why are you rebuilding an engine with only 109k on it? Do a compression test and see if the bottom end is worn out. If the bottom end is good, spend your money on heads/cam/intake and you'll be a lot happier with the results.
Reply
Old Sep 30, 2007 | 06:47 PM
  #4  
The Batmobile's Avatar
The Batmobile
Thread Starter
Instructor
 
Joined: Sep 2007
Posts: 175
Likes: 1
From: Fort Worth Texas
Default

Originally Posted by JLeatherman
Why are you rebuilding an engine with only 109k on it? Do a compression test and see if the bottom end is worn out. If the bottom end is good, spend your money on heads/cam/intake and you'll be a lot happier with the results.

I dont know much about mechanics, what do you mean by the bottom end? I took my car to a mechanic because the car wasnt running right. Oil is fouling out one of my spark plugs. He said the valve seals/rings need to be replaced.
Reply
Old Sep 30, 2007 | 07:28 PM
  #5  
evmlarry's Avatar
evmlarry
Pro
 
Joined: Nov 2006
Posts: 638
Likes: 0
From: Plano TX
Default

Originally Posted by The Batmobile
Oil is fouling out one of my spark plugs. He said the valve seals/rings need to be replaced.
Hmmm... what backing was there behind the ring replacement? Did he run a leak down or compression test on it? Valve seals are easy and can be done with the engine in the car. I wouldn't just jump on a rebuild unless absolutely necessary.

If you do choose to rebuild, you really need to ask yourself what you're wanting to do with the engine. For example, I rebuilt my engine just recently and I didn't really have the money for a build up and I'm also just looking to cruise and not 1/4 mile it... in that case, I just went for a rebuild of the engine with it costing me just a little over $800 including machine shop work.

It all just depends on what your ultimate plans are and how much you want to spend on it.

I wouldn't just suspect the engine is shot due to oil fouled plugs without further diagnosis. You could end up saving yourself hundreds of dollars considering the high quality Viton valve seals go for $7.99 a box at Oreilys. If that solves your issue, then you could spend those hundreds of dollars on upgrades if that's the path you ultimately want to go.

JMHO.
Reply
Old Sep 30, 2007 | 07:35 PM
  #6  
The Batmobile's Avatar
The Batmobile
Thread Starter
Instructor
 
Joined: Sep 2007
Posts: 175
Likes: 1
From: Fort Worth Texas
Default

Originally Posted by evmlarry
Hmmm... what backing was there behind the ring replacement? Did he run a leak down or compression test on it? Valve seals are easy and can be done with the engine in the car. I wouldn't just jump on a rebuild unless absolutely necessary.

If you do choose to rebuild, you really need to ask yourself what you're wanting to do with the engine. For example, I rebuilt my engine just recently and I didn't really have the money for a build up and I'm also just looking to cruise and not 1/4 mile it... in that case, I just went for a rebuild of the engine with it costing me just a little over $800 including machine shop work.

It all just depends on what your ultimate plans are and how much you want to spend on it.

I wouldn't just suspect the engine is shot due to oil fouled plugs without further diagnosis. You could end up saving yourself hundreds of dollars considering the high quality Viton valve seals go for $7.99 a box at Oreilys. If that solves your issue, then you could spend those hundreds of dollars on upgrades if that's the path you ultimately want to go.

JMHO.

Yeah, I think Im just going to get it running right, then go after upgrades. What does it sound like needs to be done to the valves? Any suggestions for upgrades?
Reply
Old Sep 30, 2007 | 09:19 PM
  #7  
JLeatherman's Avatar
JLeatherman
Burning Brakes
15 Year Member
 
Joined: Sep 2006
Posts: 1,202
Likes: 3
From: MD
Default

The "bottom end" is the rotating assembly (pistons, rods, crankshaft, etc) and the block. "top end" is cam/heads etc. Do a compression test, or have one done. This will tell you if you need rings (doubtful but possible). If oil is being consumed because of bad rings, you'll have to remove the engine and should bore it out. If the oil is merely a head problem you have a great excuse to get a heads/cam/exhaust package for some good horsepower. Or, if you just wanna get it going again you can slap on a set of stock heads in a weekend and be goin again.
Reply
Old Oct 1, 2007 | 12:17 AM
  #8  
70ZZ3 96LT4's Avatar
70ZZ3 96LT4
Burning Brakes
15 Year Member
 
Joined: Oct 2001
Posts: 911
Likes: 5
From: TN
Default no mechanic

Since you are not into building engines yourself, inexpensive engine replacement is available from GM. Last time I looked you can get a 290Horsepower new, everything brand new, 350 engine for a reasonable price and comes with a warranty.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

 Michael S. Palmer
story-1

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-2

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-3

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
story-4

Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

 Joe Kucinski
story-5

Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

 Verdad Gallardo
story-6

Top 10 Corvettes Coming to Mecum Indy 2026!

 Brett Foote
story-7

Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

 Michael S. Palmer
story-8

10 Revolutionary 'Corvette Firsts' Most People Don't Know

 Joe Kucinski
story-9

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
Old Oct 1, 2007 | 12:38 AM
  #9  
cv67's Avatar
cv67
Team Owner
15 Year Member
 
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Default

If you are dead set on getting a motor, buy one in a crate, swap the accessor over and drop it in. No waiting for machinists, delays, god forbid there is a problem and you cant get him to stand behind it.
Reply

Get notified of new replies

To Thinking about replacing/rebuilding my engine...Need help!!!





All times are GMT -4. The time now is 02:53 PM.

story-0
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-1
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-2
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-3
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE
story-4
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-5
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-6
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE
story-7
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-8
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-9
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE