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1G Head Surface opinion?

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AlmightySo

Proven Member
263
12
May 1, 2014
New Castle, Delaware
Hey I just got my head back from the machine shop when they went to resurface the head it had a low spot and they welded it in and resurfaced it again. Looks like their welds have low spots too.. Amazing. What do you guys think?! I'm moments away from calling them an letting them know this isn't cool..
 
That's the reason I like them. With composite gaskets, the gasket will usually torch before you see damage like that done to the head. The "fuse" theory, as I've heard it referenced to.

Damn didnt see this before I posted, but it specifically proves your theory, his head is blown apart
 
The problem is a composite with no o-ring blows out all the time. That's the first mls gasket I've ever torched in years of running them. A composite gasket also ruins the surface of a block and head.


I went from a billet 3586htz to a regular cast 3076. The wastegate line blew off and I saw my 45psi boost gauge peg around 5,000 rpms and just stayed in it to see what it could do. It blew the gasket from crazy back pressure is what it did. $200 and I was back up and running in a couple days.

That head is also welded and fixed now ready to go.
 
IMO, the shop should have contacted you before they even attempted to weld and then deck. Taking liberties like that without letting you know first is not so cool. But what's done is done. Regarding the head, call me conservative, but I'd go back to the machine shop with a "guess what you guys have to make right" approach because they clearly didn't do a good job AND they did it without consulting you (right?). When shops do that kind of crap to my parts, I have a habit of holding them accountable before I put things back together. Their response is usually pretty reflective of their quality of work. If they make it right, good to go, if they blow you off, you don't want to use stuff that comes out of their shop anyway.

If you're gonna use this head as is, though, my personal recommendation would be composite gasket with a good quality fire ring (like the felpro) because that would be a more forgiving option for initial sealing AND would act as a fuse for a head that was surfaced with questionable results.

Good luck, man :)
 
The problem is a composite with no o-ring blows out all the time. That's the first mls gasket I've ever torched in years of running them. A composite gasket also ruins the surface of a block and head.


I went from a billet 3586htz to a regular cast 3076. The wastegate line blew off and I saw my 45psi boost gauge peg around 5,000 rpms and just stayed in it to see what it could do. It blew the gasket from crazy back pressure is what it did. $200 and I was back up and running in a couple days.

That head is also welded and fixed now ready to go.

Yeah they rebuilt that aluminum bridge that blew out over the coolant passage, EASY

But of course the head and block are RUINED and can never be reused again from all of that icky graphite.

ROFLROFLROFL
 
Block was fine, I checked it with my starrett straight edge, and better yet it's running 30psi again.

I welded the head myself and had it milled for $60.

I used a new cometic gasket for $70.


The more you can do yourself, the cheaper it gets to build/operate a modded car.
 
The more you can do yourself, the cheaper it gets to build/operate a modded car.

Fact.

The composite gaskets are more prone to blowing, which I'm fine with if it saves me hard parts in the end. When I work my way up to 40 psi, I may reconsider. Give and take, that's always how it pans out.

I just recently popped my head gasket toying with a overly hot timing table, so we'll see how everything looks when I get it apart. I need to find a machine shop that will deck a head for $60 bones, though. That's legit.
 
Fact.

The composite gaskets are more prone to blowing, which I'm fine with if it saves me hard parts in the end. When I work my way up to 40 psi, I may reconsider. Give and take, that's always how it pans out.

I just recently popped my head gasket toying with a overly hot timing table, so we'll see how everything looks when I get it apart. I need to find a machine shop that will deck a head for $60 bones, though. That's legit.
I'm at the machine shop every week to drop off and pick up, I get volume pricing.

I love the composite gaskets with a stainless o ring in the block. I ended up going mls because it holds up longer, and doesn't need any work to put back together after a routine tear down.

I usually tear it down every year which for me can be 10,000-15,000 very hard miles. Using the mls gaskets made that process easier.
 
So youre saying the extra $100 for the gasket is worth it so you dont have to spend 30 minutes cleaning the block

Or are you saying you bring extra heads with you to the race track because when you blow them apart its quick and easy to do a gasket slap in the pits?
I'm saying the composite gasket didn't usually make it a full year, and the head had to be resurfaced every time I took it apart from the o ring digging into it.

When I go to the track I usually only bring a spare trans. That's the first head I've torched in about 100,000 miles of 500-800hp driving.

If you have anymore questions I have answers for years, I've been doing this for a long time. I can also build you a car that runs faster than 14's if you'd like. :)
 
and the head had to be resurfaced every time I took it apart from the o ring digging into it.

Interesting. How did the composite gasket hold up with the o-ringed block compared to without it?
 
Interesting. How did the composite gasket hold up with the o-ringed block compared to without it?
I wouldn't run a straight composite over 400hp, but that's just me.

With the o-ring they hold anything I've thrown at them. They don't blow, they just end up pushing coolant after lots of abuse.

For extra sealing you can get the block and head o ringed so that they interlock. You'll never "blow" the gasket. It may push coolant but it won't just blow out.

It's all about your application and goals. For what I'm doing with my car the Felpro mls was the best option.
 
He said bring the head to him. But I'm still unsatisfied with how they surfaced my block. The resurface they did on my head is smoother than how it turnt out on the block. I can feel grooves with my nail. He keeps telling me its "OK" to run a MLS with this finish, but deep down I don't think so?
 

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He said bring the head to him. But I'm still unsatisfied with how they surfaced my block. The resurface they did on my head is smoother than how it turnt out on the block. I can feel grooves with my nail. He keeps telling me its "OK" to run a MLS with this finish, but deep down I don't think so?
Do u have a good picture of the deck surface.... like the entire block. That does look alil crusty
 
Looks like that head is a no-go, especially if those voids are in the fire ring area of the gasket.

The block may be ok. Ask him what the ra is if he's so sure it's good.
 
I've asked him numerous times, he doesn't have a way to measure it I guess.. he just says "It's OK"
If I have him re-weld and resurface I should be okay right?
& What does lap the block mean?
 
Aside from the surface finish and the structural issues, another thing to keep in mind is that every time you go back and have the block, head, or both resurfaced, you're raising the compression ratio. I assumed you started with an engine with an 8.5:1 compression ratio to back calculate your initial quench volume and assumed the standard 85 mm bore and 88 mm stroke of the 4g63.

Assuming the machine shop takes off 0.010" per pass on both block and head (which is a reasonable estimate), the following graph shows how the compression ratio increases every time they make a pass on both the block and the head:

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If they're either doing the head or the block by itself, the trend looks like this:

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.010" is the most you want taken off the block or head. I usually toss a head if it needs more than .003"-.005" cut to clean it up, and I don't use warped heads.

The last head I welded had .0005" cut off it at the machine shop to clean it up.

The more you cutvs head the thinner the deck is, and the more likely it is to flex and blow a gasket.

I wouldn't cut much off a block either because of changes in piston to head clearance.
 
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