Hello everyone! So im thinking about getting a new cylinder head with valve guides and seats installed, and then i will put in new valves. Can i throw in the new valvez and go? Or do i need to do some sort of machining to the seats?
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Hello everyone! So im thinking about getting a new cylinder head with valve guides and seats installed, and then i will put in new valves. Can i throw in the new valvez and go? Or do i need to do some sort of machining to the seats?
You'll have to at least lap the valves in with some lapping compound. I would avoid Odessa and Clearwater cylinder heads in Florida, they will rip you off
Thats what I was thinking, thanks for the response. And a BIG thanks for the warning!
Hi, I don't mean to steal a thread, but I was wondering, does Odessa make bad cylinder heads? Because that is exactly where I was thinking of ordering a head for my G63B. The head I was thinking about getting is 280 bucks, shipped. Maybe I'm looking in the wrong places but I can't seem to find one much cheaper than that.
The truck has 234k on it, it was overheated and the head had an obvious crack between one set of valves, so instead of trying to repair the old head, I figured I'd look for a new one.
Odessa cylinder heads is the name Clearwater came up with when they had run there name into the ground. Google Odessa or Clearwater cylinder head review and see what comes up
Here's the skinny on them.... they're Chinese heads. It's hit or miss with them. I'd definitely suggest that they have no quality control being practiced at all, and even less verified by the seller. I have seen the sellers inventory here in Vegas (who sells the same chinese heads) and they looked good to go.
Point is, don't expect an OEM quality head out of the box. All the shit reviews are from people pissed off about getting a head that wasn't QC'd. This of it this way, one bad review wipes out 10 good ones. Most good reviews don't exist because people LOVE to complain when they thin they were done wrong, but rarely say something was good when it actually was.
Take your chances with open eyes to make probable disappointment less of a shock.
I've spent a lot of time researching heads. Odessa says they use CFIC heads and valves from a US supplier in Las Vegas. Heads from ITM seem to be sold mostly as bare units and are reputed to be of decent quality. You can add your own parts to an ITM casting but the cost adds up, especially if you get a machine shop involved. Around here you cannot get in and out of a machine shop for any less than $200, and that is just cleaning and inspection, if that. This makes the complete heads seem pretty attractive, but unless you disassemble and measure everything you have no idea what you are getting. This is always the dilemma with fixing an old engine, and is why the average dude would be time and money ahead by buying:shrug: a newer better truck. But that wouldn't be any fun would it?
Yeah stay away from Odessa/Clearwater heads. They are getting roasted from their facebook reviews. "Good" quality valvetrain parts won't fix a bad head. That being said, there are decent heads coming out of China. Machine shop labour is always at a premium and is where the bulk of your money goes. Joe average can do a leak down test and run a straight edge over a deck with feeler gauges to see what the tolerances are like and even DIY porting and head mods aren't out of the scope of the someone with limited experience (advice and methods are plentiful on the net). But without a valve cutter and a milling bed, you have limitations (don't be that moron on youtube that decks their heads on a sheet of emery paper on their outdoor table...)
not even a glass top table...lol
You seen it too pennyman? And the best part - the idiots that have commented on his vid that they've done this as well and thanked him for the tip. :bang:Quote:
Originally Posted by pennyman1
i haven't viewed said videos, but I've seen a cyl head or two 'surfaced' on a homemade table. Held up fine on boosted applications
I've hand lapped valves myself, no isuues
Even watched an old school rotary engine buddy 'surface' rotary housings similarly. His personal ride was a self built/tuned single carb turbo 13B, widebody 1st gen.... was the 1st airconditioned daily driver I rode in that broke traction @70-80mph at part throttle!
I have read about using sandpaper on glass as a backing on a bench to ensure a flat surface, and using a honing block to deck cylinder block mating surfaces. Not sure I would try it, but to each his own. Then again, some go cheap and wonder why things fail...
I have seen double gasket-ed heads before. The guys excuse was he couldn't afford it. Well, you could afford buying another gasket, couldn't you. I just thought that last part in my own head. There is no way you will ever be able to make a turd shine.
and that is what head saver gaskets are for - to bring the head back to where it was before shaving. They also make custom thicknesses to lower compression for turbo applications.
A few more comments on heads: A glass plate is very flat, probably flat enough, but just try taking off more and a couple of thou using sandpaper - it takes forever!! Plus it's really difficult to take off the exact amount across the head surface. Usually one corner or one end gets too much reduction, or not enough. I used to do precision grinding at work and it is not that easy to keep something flat.
It is legitimate to check your head with a straight edge and feeler gauges, but you need a really good straight edge that is long enough and they are somewhat costly. If your head is more than a few thou warped you can either have it cut or buy a replacement ITM head for about $260 and have a brand new head. That is really tough to beat and the ITM heads are reputed to be excellent quality.
On a warped head, my machine shop said that if you tighten down the cam caps and your cam still turns by hand, you are good to go. Usually there is enough clearance in the cam bearings that minor warping is acceptable, but too much drag is obviously a problem. My head was warped only 0.004, so I had it resurfaced and touched up the valves and seats. If they don't take too much off, say only about 0.006, you will be OK, or just buy the new ITM head, it is not much more than the machine shop charges to clean, resurface and rework your old head.
If you want to have all new parts you can order the "famous brand" rebuilt head from Rock Auto for about $450. They don't tell you where they get them, but I am reasonably sure they come from ATK, or at least they use an ATK part number. These are more expensive than the Clearwater/Odessa heads built on new Chinese castings from CIFIC. Both ATK and Clearwater have many horrible reviews, but also good reviews, so the quality of the parts will be unknown, but you almost certainly won't be getting high quality valves, springs, and a cam for that price. If your head and valve train is really shot the replacement head, though questionable, is probably better, but you'd better look it over VERY carefully.
Or you can buy the bare head from ITM and build it up with new quality parts from Rock Auto for about $650 and really know what you've got. It's not that much more, considering all the labor to remove and reinstall a head.
Or best of all you can buy all new parts from Mitsubishi and assemble them, but the bare head is about $670, plus the valves are pricey, and who knows if they are any better, but you will have an OEM set up for under $1000. There is always someone out there who has to have OEM.
Given that shops around here charge $2000 to properly replace a head gasket, including reworking the head, you can come out way ahead even using OEM parts!
a starion clubmember built a mitsu dohc 2.4 street rx7. Dyno'd 564hp using a $30 stock hyundai head straight from u-pull-it
If facing pumping money into a sohc, can't help thinking about all those $30 dohc marvels just sittin out there - lol
so the bare 2.4 sohc cyl head needs valve guides and seats installed, at minimum.
I'm thinking they can cut a 3 angle seat. Is it feasible to lap in your old valves (if they're fine) ?
My plan is to use the mechanical shaft & rockers from a 2.0 + performance cam + upgraded springs
Always preferred the smoothness and simplicity of the sohc, and intend to see how far I can take it boosted
The 2.4 is hydraulic - the 2.0 is mechanical. There may be key differences that will prevent it all going together (cam lift and duration, the cam journals themselves, oil feed through the galleries etc) If your old valves haven't been beat on they can regrind them which is advisable anyway. Hopefully they can do a proper valve polish (I've seen some shocking work...) With stock internals it should make 300 HP but you need to factor in fuel delivery and what kind of turbo you're able to mount on it. If viable, go looking for a DASH 2.0 turbo top end - with everything. It's still a single cam engine but it ran a split pulse turbo manifold that aided the turbo spool up time. One of these beasts -
http://www.ebay.com.au/itm/Mitsubish...EAAOSw241YhnXn
All you'd need to do is change the thermostat housing to face outwards and run a coolant pipe for it.
seen a few really impressive street 2.4 sohc, both @ only ~15psi max, 55-60mm turbo
Wanna explore limits of stock bottom end, then go wild @30-35psi on custom pistons. Brand new head intended
2.0 sohc is savage at that point, so..... bigger displacement & better flow heads should deliver
Somewhere in my notes, austarion members say, 2.0 staz mech valvetrain/cam 'bolts-on' iirc (just as we do the 2.6)
I can't find the article but we had a guy who built a 1.8 Cordia turbo with forged pistons and wrenched 384 HP out of it @ 5,500 rpm. This was a destructive engine test to determine the 'safe' limits of the 1.8 turbo. After the test the guy (I remember his last name was Rigoli - he ran/runs a race engine building shop) pulled the engine down, it looked like someone had taken a rotary hammer drill to the pistons and messed up the head pretty badly. The 2.0 sohc would probably be at it's limit by 350 HP with forged and balanced internals. The 4G63 twin cams can flow a stack more air and you know what kind of HP they are capable of :grin:
seems like the exhaust manifold, turbo hotside, intake manifold and/or cam, is the limiting factor
once those restrictions removed, who knows how far the 2.0 sohc will go.
One street staz did, and wound up with "far more power than can be used on the street"
Another clubmember testified, "you'll never consider a twincam conversion, after a ride in that beast".
All from a relatively small turbo; 16g @ 28psi... so I'm sure the 2.0 will go way past 350
The single ECI injector set up up is no good for building power. Getting a MPI intake is the way to go. It will reduce the risk of running it lean. The good thing about the SOHC head is it already has a location to hook up an oil feed for the turbo.
Oh no, TBI out of the question if chasing power. Sonata or truck MPI has satisfied most, then there is 'custom'.
Staz mentioned above ran ITBs with a plenum cover. Split pulse cast HKS exhaust manifold + 16g gave fast turbo response and broad tire frying torque curve. Mind you, EvoIII 16g is a phenomenal "small" turbo proven @ 400+hp cranked up.
A different turbo and header would be used if going after big power. Owner builds 'race' motors, so he knows....
http://beyondthelimit.com.au/sca/index.htm also built some nice 2.0 sohc staz back in the day. Lotsa info still on that site