Innocent Fool

I think it stands for aRithmetic Average or Roughness Arithmetic Average
Something like that...

BlueGTS

Great tip on the new gasket set as the one I was going to order did not say that. I know my 1996 had a HG recall that was not performed and now the recall is not in Toyota's system as an active recall.

I read on another forum that the stock bolks can pop if re-used so I will buy new ones and would rather not get TTY depending on the price difference.

Do you know if the new head bolts come with the washers or did you purchase those seperate? Or did you re-use them?

mt_goat

Arithmetic average of absolute values.

More on that: http://en.wikipedia.org/wiki/Roughness

BlueGTS

I am actually unable to find any gaskets that say updated on them. I have also noticed big price differences between Ishno and Fel-Pro. Fel-Pro being more expensive for the entire kit. Since Ishno is OEMish I am leaning toward that but the fact that it is cheaper is throwing me a bit. I also see many different makes of head bolts. Fel-Pro being the cheapest and Beck/Arney being almost twice as expensive. Any thoughts on that?

mastacox

My thoughts would be all-OEM, which is the way I went. There are a lot more gaskets in there than just the head gaskets, and if you're pulling the engine apart several will need to be replaced. I decided I was best off getting the full engine rebuild gasket kit from ToyotaPartSales.com. It costs around $400 and has every conceivable gasket you will need for the engine. Pricey, but worth the peace of mind for me...

BlueGTS

They have it for $388 which is the price of the Fel-Pro kit. However, the Fel-Pro kit comes with valve stem seals and head bolt washers. Does the Toyota kit come with spark plug gaskets? How about washers for the head bolts? I don't see head bolts on that sight, do you remember how much you paid for Toyota head bolts? Thanks,

mastacox

If they're the same price, I would get the Toyota OEM kit hands down.

Yes it comes with those.

It doesn't come with the head bolt washers, but I just reused the ones in there, that's fine. I don't remember how much the bolts were honestly, maybe $100 or so...

hross14

Mastacox--he needs to consider how smooth he is going to get both surfaces before he decided what he is going to by. Fel-Pro and aftermaket kits are more suited for rougher finishes.

I am going to say stay away from OEM UNLESS you know you are getting your heads and block ultra smooth.

hross14

I would agree with Mastacox that a total engine rebuild kit would be the way to go....there is always somehwhere odd gaskets get used down the road.

http://www.napaonline.com/Search/Det...+2070015+25010

Read the verbage here--this is what I was talking about.

"Correct Technology for MLS Equipped Vehicles.; Features Exclusive Aftermarket Coatings to Accommodate a Wider Range of Surface Finishes"

mastacox

When I rebuilt my engine's top end, I got remanufactured heads which had been machined to spec. For the block all I did was scrape off the old gasket material, it was still very smooth.



If you're planning on having your head decked, you can just specify a surface finish so it's within spec for the OEM head gasket (it's a simple machining operation); if you aren't doing anything with it the it should still be smooth you'll just need to scrape off the old gasket material (although bulk warping could be an issue, which is why decking is a good idea). In either case, there wouldn't be any reason that your surface finish would end up outside the capabilities of the OEM head gasket.

mastacox

There were a lot of odd gaskets in the kit that I wouldn't have known I needed until I had the engine apart. When you add up the prices of all the gaskets in the kit, $380 is a very good deal.

BlueGTS

I had not planned on sending the heads out because the truck never overheated and sometimes shops can do more harm then good. I will do the straight edge check per the FSM tonight and see what I am dealing with. I did a quick check when I first pulled them and I did not see / feel any warpage. I was going to pull the trigger on the OEM gasket set today but now I am a little concerned about my surface smoothness. I will scrape the heads tonight and see what I am dealing with. Thanks for the input guys.

hross14

There arent many shops that even know what RA finish thier machine can provide. Many head shops dont have machines that can achieve an RA under 50.

GTS--Make sure the shop knows what it is doing and is capable of.

I know the truck didnt overheat but i wouldnt put those heads on without sending them out. Once you start scraping those heads, little bits and pieces are going to be shaved off--....get what i am saying here? That affects/effects (gramar check) the sealing surface.

If you are not going to send them out them i would seriously consider Fel-Pro, Victor Reinz.

Dont you think it is better to spend $300 more and not worry so much? Do you have a machinist straight edge that is accurate to +- straight to within 0.0002" per foot of length and parallel to within 0.0004" per foot of length.

Just food for thought all.........when i rebuilt mine--i did reuse most of the sensors--i replaced most of them. See, thats how I think--why wait for it to break? just do it? Tiger did HHHaaaaa

BlueGTS

Arrgghh, that is exactly what I didn't want to hear. I would love to just scrape the gaskets off, (with a plastic scraper) and slap the heads back on. You are definately right about going the extra mile and sending them out. However, I have seen a lot of bad work from head shops and I would hate to spend $250 and add to my headaches. My 2 week projects always turn into 4 month projects. I hope this one is not heading down that same path.

mastacox

I would be very surprised if the shop didn't know what it is, and if they don't I WOULD NOT use them. Getting that surface finish is not a difficult thing to do, it's basically just a speed setting on the mill (the slower you go, the better the finish). It shouldn't be hard to find a shop that can do what you need.

You can get the heads plenty clean with a plastic gasket scraper and possibly a metal paint scraper (as long as it's wide and flat). Decking is best, but just because you scraped the gasket off doesn't mean you've totally ruined the finish; just use common sense when scraping and don't get impatient or overzealous.

It's true, a plain ol' straight edge will not give you a useful flatness measurment, you need something more advanced.

Scraping the gasket off with a plastic scraper is fine. Using a screwdriver, not so much.

Most shops recommend you deck aluminum heads every time you take them off due to thermal warpage (its unavoidable). You can just put them back on, and they'll probably be fine, but no guarantees.

Keep in mind also, if you're getting the heads decked, that means you or the shop will have to completely disassemble them, which means since it's already apart you might as well get a valve job and rebuild. This means more money up front but not having to kick yourself 20k miles down the road when a valve seat goes and you have to do it all again.

If you decide to go the rebuilt heads route, I would recommend getting remanufactured heads, I got mine from here and they were very nice to deal with: www.cylinder-heads.com. I got a pair of remanufactured heads for something like $600, and they included shipping labels to ship the old heads back for the core. Very easy, and nice because I didn't have extra downtime getting the old heads rebuilt.

mastacox

I definitely feel you pain about job scope- my head gasket went and when everything was said and done and back together I had spent about $1500. It's hard to limit the amount of "well since I'm in there, I'd better do this..."

For me it was new remanufactured heads, all new timing components, new water pump, new gaskets everywhere, etc. It all adds up fast, that's for sure. I basically decided to limit it to above the pistons, but it could have easily creeped to the bottom end if I had another $700 or so...

hross14

And i creeped into the bottom end.......HHAaa

If you were in Texas--i could show you where to go--Mastcox--in a perfect world machine shops would know what they were doing--but i cant tell you how many i have ran into that didnt

Or surface the heads yourself with a thick piece of glass and patience.....