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head gasket?

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Wookie, the new torque specs should have come with the MLS headgasket. The spec sheet comes with both the full upper gasket kit as well as just the headgasket kit itself. If the sheet is not in there then let me know and I will find one at work and give you the changes.

Racer-X uh, yeah... that is kinda important info to know. I was reading straight off your post and not the info on the left. Please clarify which it is because most of the info I have supplied as well as others may not help your particular case.
Doug
 
hey guys, sorry for the confusion... yes, i am refering to my 420a 98' gs (the red one in the pic), and yes i recently bought a talon tsi awd in jan. that one will be my project car when i can come up with some extra money and get my gs fixed; which i may sell or use to drive to and from work. still not sure on that one though. my wife is getting upset with me cause i have 3 cars and i'm still looking for a 99 gsx. she says our drive way and garage looks like a car lot. i have my 02' S4, 98' gs, 96' tsi, but if i find a gsx i will more than likely sell my gs to buy my wife something else.. if i don't she my kill me. oh well, what can i say... i like my cars.
 
Doug, arent you the guy that sells the jeep TB upgrade? If so how do you like your cash sent to you and what kind of wait is there , off course the head is at the machine shop so its not a flaming hurry.

Dodge just got my head gasket kit in today, the specs where in there. Thanks

How much can the 420 head be resurfaced and still use the factory head gasket? If the machine shop has to take any off will I be okay with that MLS?
 
Yeah, Me and my friend Toney (1TuffRS) sell the Jeep Throttle bodies. THere's quite a few threads already open about it in the N/T performance section. Feel free to find out what I do to them, the turn around time, payment methods and so on.

My neon had 0.010" taken off and that's with a crane cam going in it with moderate overlap. My eclipse is getting the stage 2 cams from crower with howell oversized valves. It's only been milled a couple thousandths to get it flat. There was some pitting in the head and since I'm not going all out with the cams or building the bottom end then there was no need to maximize the milling on the head. Plus... the pitting is from corrosion and basically is corroded at the weekest spot. So we don't want to mill alot thus raising compression alot and create too much pressure. Talk with your machinist about the cam grind your using and how much port work is being done. If the cam grind is agressive then you'll want to maximize it by milling a bit more off. But keep in mind the more you mill, the less clearance you have to the pistons. I wouldn't go more than about 8 thousandths if you're not having the entire engine professionally tuned. Both my neon and the eclipse had the head work done by a professional machinist. I'm putting them back together.

It's not so much of how much can the MLS headgasket handle as much as it is the length of the head bolts and the clearance between valve and piston. This would be something you'd need to talk with your machinist about again or someone who professionally modifies these engines.

Doug
 
So I had planned to put the factory cams/gears back in , reason being that I think its fun when a car idles smooth and the money for this particular project is growing thin. If you were trying to keep costs down,idleing smooth and performance up what would be the best thing to do?

What about the oversized valves? well then I would need different seals. this is the sort of thing that I dont particularly want to do twice so I outta get it all on the first crack.

To think all of this was to make an oil leak stop so I could put my new exhaust on.......(couldnt stand to see oil leaking all over that pretty stainless)
 
The stainless steel valves are larger at the seats but not at the valve stem so you won't need different seals. That would be a nice little bump up that shouldn't really affect idle. You could do the springs and retainers now too since the head will be off. There won't be any performance gains to speak of there but it's one less thing to do later. You could also mill the head at this time as well as having the head ported and polished. These are all things that would require the head to be removed (except the springs) and so you could knock all that out at once.

You could always go back in later with cams and gears and wouldn't have to pull the head again. Just the valve cover and timing belt.
Doug
 
I guess I could go with the bigger valves then , cost 125 to have the valves done on a head, new ones are only 240ish from howell. So I might be further ahead to do that. As far as the porting and polishing , my little local machine shop said that they cant do it. There are some places in columbus that do it for 50 per port. Thats a lot of money for a little grinding. How big of a difference does the p&p make?
 
The cylinder head is where you make your horsepower. You can spend gobs and gobs of money on the bottom end but you won't get a significant increase in horsepower. All you'll get is a well balanced bottom end with very stout parts. Get air in to the cylinder is the job of the head. Valves, porting and polishing, cams, and throttle body are the components that sucessfully make that happen. Yeah, it's not cheap. But let's do a quick comparison. My neon runs 15.660 in the quarter. Toney runs a couple of tenths quicker. I'm on stock exhaust he's got a gutted cat and cat-back. He's got an UDP, I've got the mopar performance computer. He's got cold air, I've got stock. Both are five speeds and I was running the stock 165R13's he runs the 17" GSX wheels. Stock he has 140 hp I've got 132.

I've got the head milled 10 thousandths, match ported intake and exhaust ports, polished exhaust ports, crane cam, cram springs and a three angle valve job.

I think that it's well worth the money to do it right the first time. I hope to have pics of my eclipse by Sunday so I can show everything that I'm doing with it. I paid $325 for all that work on the neon and I feel very strongly that is worth every penny. Just look here:
http://www.dsmtuners.com/forums/showthread.php?threadid=40045&goto=newpost
scroll down and find the link from LandoAWD's imagestation page and find my neon in there.
Doug
 
Just to reinterate , before I tell the machinist not to bother with the valve grind. The head need not be modified in any way to accomodate these oversized valves?
 
That's incorrect. The new valves are larger so they will need to be fitted to the cylinder. My machinist also did his own valve gring on them he said just because he does that to all the valves. Outside of that no more work will need to be done except lapping them in which the machine shop should do.
 
so to maxaize the potentional out of our existing block how much porting should be done and where? i also heard that you can increase hp by milling the block and increase tq by making the block taller... is this true?
 
To the block you can neither port/polish nor raise the block. If you "raise the block" then I'm assuming you mean lower compression. This can only be done by boring the cylinder walls to make them larger in diameter, changing out pistons that will be dished, installing some sort of extra thick head gasket, or by doing a stroker kit.

By milling the block you are raising compression. In most cars this will increase power gains. However, on forced induction cars tuners prefer to lower compression. You can raise compression and get equally desirable results however the window for tuning becomes smaller. A slight tweek changes alot more on a high compression car versus a low compression car. It's safer not to run high compression because turbo'd cars are very sensetive.

As far as how much porting, milling, polishing, measurements on clearances and so forth I could not answer those questions. I can take everything apart and put it back together. But once I change from stock application I don't know alot. I had the spec sheet from the cams, the oversized valves, the bare head, the springs and a few other odds and ends in a box. I handed them to the machinist and said here is what I want in it, this is what's done to the car, and these are the risks I am going to take, these are the risks I'm not going to take. Put it together. And he did just that. He punched in numbers in to his computer did this, did that and here I am tonight with my eclipse sitting outside my apartment for the first time in nearly three long.... miserable... weeks.
 
The cam sensor seal was probably leaking all along. The upper gasket kit comes with a new cam sensor seal which should have been replaced during the head gasket repair. Also, if the camshaft caps were not sealed properly then they could be leaking oil as well.

In the picture below is the head from my car. The dark discolored caps hold down the cams as well as act as part of the sealing surface for the valve cover. If you'll look to the far left of the screen at the last cap, it's quite long compared to the rest. In the middle you'll see a red color on the bottom side. Both that cap and the one closest to the camera that you cannot see require that red sealer underneath of the caps. Then, at the end of the cap RTV is supposed to be used to seal the valve cover at the corners. If they didn't do this then the valve cover could be leaking as well.
Doug
 

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This pic shows the Multi-layered steal headgasket spread out. It's from a different car but it's still of the same design. On the ground is the old headgasket from the eclipse.
 

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This is the stock headgasket. It's all one piece. The air hose is pointing to the area that always leaks. It actually fell apart during removal. There's supposed to be smaller ring inside of the oval shaped whole. But... it fell apart and stayed on the block during removal.

The heagasket is laying just like it would lay on the car. The air hose end is cylinder number 4, the opposite is cylinder #1 closest to the belts.
Doug
 

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Originally posted by Doug99RS
The cam sensor seal was probably leaking all along. The upper gasket kit comes with a new cam sensor seal which should have been replaced during the head gasket repair. Also, if the camshaft caps were not sealed properly then they could be leaking oil as well.

In the picture below is the head from my car. The dark discolored caps hold down the cams as well as act as part of the sealing surface for the valve cover. If you'll look to the far left of the screen at the last cap, it's quite long compared to the rest. In the middle you'll see a red color on the bottom side. Both that cap and the one closest to the camera that you cannot see require that red sealer underneath of the caps. Then, at the end of the cap RTV is supposed to be used to seal the valve cover at the corners. If they didn't do this then the valve cover could be leaking as well.
Doug

so basically the people who fixed the HG did a poor job. they said that since i had aftermarket cam gears, the gears had a nik on them and they were rubbing on the cam seals. also they said there was aome corosion on the camshafts too. Basically they wanted to charge me another 800 dollars.
 
This is another motor job I'm in the middle of. Note the staining left by the oil used. Chances are it's NOT had synthetic oil used. It's only got 30,000 miles on it and stained real bad.
 

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This shows my cams and cylinder head parts that did not go back in. I had 70,000 miles using mobil1 synthetic. The other drawer shows some cams and head parts from another car. I don't know the mileage but I can just about promise you they didn't use synthetic oil.
 

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The cam seals should not be even close to the gears. The cam seals sit underneath of that long cap I pointed out early. Then the timing cover is installed and then the cam gears. There's nearly a full inch from the gear to the cam seal. Sounds like they may not have done everything right the first go round.
 

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Go back to them and get your $800. There is no way a cam gear can touch a cam seal, there is a plastic timing belt cover inbetween them. Tell them they are full of shit and get your money.
 
I have heard of getting "Too Much" air into some other N/A vehicles.

If a brother where to go with the jeep throttle body , ported and polished head, and the larger valves is there a chance that this would be too much air for the factory fuel system to keep up with?
 
Not in my opinion. I mean the n/a to turbo boys are still running the stock injectors on them. I've got all that work done to my car now so if it's gonna run out of fuel... I'll let you know. But I seriously doubt there will be any problems.
Doug
 
Originally posted by Doug99RS
Not in my opinion. I mean the n/a to turbo boys are still running the stock injectors on them. I've got all that work done to my car now so if it's gonna run out of fuel... I'll let you know. But I seriously doubt there will be any problems.
Doug

Actually some of the people who did the conversion are running 310cc injectors and I plan on doing the same once I have my kit in. Their old injectors were burnt and cracked from high fuel pressure.
 
so doug what kind of oil would you recomend? also since the head is off what should i have done as far as performance modifications, and what should i look for to make sure the block is in good condition as well as the rest of the components.
 
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