PDA

View Full Version : other things to change/modify well changing head gaskets



Csirny
01-30-2014, 06:20 AM
I would just like to get some input or suggestions on other things to address as long as my engine is turn down far enough to replace the head gaskets. the car has approximatly 115,000 miles. so far i am planing on replacing plugs, wires, doing some porting, headers, and refreshing the the supercharger. also any oppinions on teflon coating my own rotors (myself in the oven) or are the tolerence of the rotors to closeto add the extra meterial.

99GSXR750
01-30-2014, 10:00 AM
Motor mounts since you'll have no problem getting to them with the accessory brackets off. I think Charles at Magnum Powers offers recoating of the rotors.

Jimmy 2Coupes
01-30-2014, 10:13 AM
ARP head studs for sure. You might want to consider doing some bottom end work like crank and rod bearings since the heads will be off anyway. From what I've read on these boards it seems once the head gaskets go on these cars the bottom end is not to far behind in most cases.

BLOWN38
01-30-2014, 11:19 AM
A cam too!

aroot1
01-30-2014, 11:33 AM
The bottom end letting loose after a head gasket blows is due to bearing damage because of the coolant contaminating the oil. I have had several sets blow between cylinders, not he cooling jacket to crankcase and it has not been a problem IF no coolant got to the oil/bearings.

I DO NOT think you want to try to coat the rotors yourself :eek: Even the factory stuff seems to have a problem with flaking with elevated boost. Send it to Magnum Powers.

Send the heads to David Dalke at Supercoupes unlimited for port work and bigger valves. These heads do not respond especially well to porting unless you up the valve size too. Dave is also the man if you r looking for a cam. If you do not want to go as far as a cam 1.8 roller rockers and pushrods to match give you greater lift, and slightly more .050 duration, again, talk to XR7Dave.

O2 sensors, the coolant in exhaust when the heads went DID smoke those.

Adam

Csirny
01-30-2014, 02:42 PM
thanks for the suggestions. About how much does the head work usualy run? I did find a set for $1,200 profesionaly ported with the bigger valves and new springs.I was strongly considering these but wasnt sure if i wanted to spend the money just yet. This head gasket problem happened well i was in the middle of another project. I was trying to keep my buget for the whole project under $1,500 for now but we all know how that goes so its not set in stone.

decipha
01-30-2014, 05:04 PM
You might want to consider doing some bottom end work like crank and rod bearings since the heads will be off anyway. From what I've read on these boards it seems once the head gaskets go on these cars the bottom end is not to far behind in most cases.

This man speaks the truth, ive had 4 of my own supercoupes loose bearings after headgasket replacement

These days i just yank the engine and rebearing it hone and re ring it at the same time

Im too lazy to yank engines more than once

superdadsc
01-30-2014, 06:22 PM
Agreed with Decipia! You are already there so do it all and drive it for another 100k!

There are ways to do the engine without buying the farm! That is as long as 300rwhp plus is OK.

S_Mazza
01-30-2014, 07:25 PM
This man speaks the truth, ive had 4 of my own supercoupes loose bearings after headgasket replacement

These days i just yank the engine and rebearing it hone and re ring it at the same time

Im too lazy to yank engines more than once

Pretty good answer. You DEFINITELY want to check the motor mounts and power steering system carefully while you have most of this apart. So pulling the engine for a refresh is not a bad idea ... IF you have the facilities. But then again, if you don't have the facilities, you won't want to pull it if the bearings fail a month later!

My red car is currently a little over 200,000 miles. I replaced the HGs at 150,000 or 160,000 miles. No bearing problems at all. But an inspection to see if coolant is in the oil is definitely in order at a minimum.

superdadsc
01-30-2014, 07:54 PM
3.8L is a very stout motor. Over the years it has been proven time and time again.
Sometimes we need to do things to get it back on the road because of funds.
To me the most important part is being able to drive my SC.
That's why I bought them to begin with!

HwyStar
02-02-2014, 01:39 PM
+1 To at least a cheap build of the bottom end. I locked up two engines, both had head gaskets replaced ~50k miles before.

Tedor
02-03-2014, 07:27 PM
Contact Dave Dalke (XR7 Dave) for some nice heads and a cam and valvetrain, ARP and MLS head gasket. Spend the money you had for the headers on heads etc instead. Stock manifolds can be ported to flow good.

XxSlowpokexX
02-04-2014, 01:53 PM
I have blown headgaskets MANY TIMES lol...Never had a bearing issue. Thats a whole new ballpark of problem sthere.

Definitely do at a minimum

new belts
motor mounts
plugs
wires.
ARP head studs fo ra 2.8 chevy
Get heads checked out and at a minimum new valve seals and springs

If you want to upgrade now is the time to do that cam and any other headwork..But you know how that goes...injectors...tune..larger this that..gets pricey

Scott Long
02-10-2014, 04:10 PM
If you do the cam, you better do something about the harmonic balancer or you'll be replacing that soon. If its never been pulled and you aren't changing the cam, leave it alone. Once you pull the factory balancer and put it back on it will fail soon after. These cars are old now, and the balancer is a press fit. Removing it and re-installing it will increase the tolerance and it will start to vibrate and then shatter around the hub and fall off the car. I've seen it on 2 of my 3 SC's. On the first one, the balancer fell the f.ck off while I was driving down the highway. That was an expensive tow and a pain in the ~~~ to fix. The BHJ balancer is your best bet. So budget another $400 for that if you plan to do the cam. These cars aren't cheap to mod since you usually can't just change one thing, you have to change a number of things at the same time (blower, maf, injectors, tune for example).

This reminds me, I need to order a BHJ for my 92 so when I put it together and do the cam I won't be re-installing an old balancer.