Builds 1fz-fe rebuild

[satchel]

Agreed, my problem is that I'm not sure there is a valid option for a head gasket that gets me exactly back to stock. I think I would need to be around the .088 thickness but I'll know more once I have done a full compression validation. Otherwise it looks like my options are .066 thickness and something like 1.2 thickness for a cometic, meaning either just on the cusp of still running unleaded, or compression fairly far below 9 I believe. If anyone knows of a better option let me know.

In the meantime, does anyone have any thoughts on how thick of a head gasket I can go using OEM (new) bolts, or should I just bite the bullet and get ARP studs?

That makes sense now. Either way I'd try to get as close to the stock compression ratio as possible then you'll be covered for both scenarios.

 

[ZackR]

Give it a few hours and plenty of replies will come in on this topic. Personally I'd go slightly higher than lower for the compression ratio if I had to choose between the two, unless I was for sure going with a turbo.

 

[satchel]

Yeah if I can keep it around 9.2 then I'm perfectly fine with that, but if it comes out that with a .066 cometic I'm still around 9.3+ then I'm going to have to reevaluate my options.

 

[Saito]

Not sure how close these motors are to zero deck, but those quench pads on both the head and pistons will be pretty useless with an .088 HG. Last I knew, an .040 or 41 was about optimal. But I may be way behind these days, too.

 

[satchel]

I think my estimate of .088 is off, looks more like .079 would net me a stock compression ratio but obviously won't know until I get my checks done. I've been wondering how close the stock pistons are to the deck surface as well. Currently it looks like my pistons are right at the deck, but considering the engine was only decked .008in, that's almost impossible for me to detect, but from what I'm seeing in the calculators, that difference is roughly an additional .13 in compression.

I'll admit I know very little about the impact of the HG thickness on the quench pads though. I have a feeling the .066 HG is going to be my only option regardless of how many calcs I do.

Not sure how close these motors are to zero deck, but those quench pads on both the head and pistons will be pretty useless with an .088 HG. Last I knew, an .040 or 41 was about optimal. But I may be way behind these days, too.

 

[scottryana]

Cometic will make you whatever size you want. They just add thicknesses of metal to the gasket. You just have to contact them.

 

[satchel]

That's great to know. Do you have any words of advice on whether I can use the stock (new) head bolts or if I should go with arp studs? I wouldn't be doing more than the wits end kit for boost, but not sure if the small addition of width or any material differences would matter.
What would your preference be?

Cometic will make you whatever size you want. They just add thicknesses of metal to the gasket. You just have to contact them.

 

[scottryana]

My preference is always a torque to yield bolt with a fiber gasket like the OEM, and a solid stud with the Cometic MLS gasket. So if you stay OEM gasket stay OEM bolts if you go Cometic gasket go ARP studs.

 

[satchel]

Perfect, that makes my decisions much easier. Thanks again.

 

[satchel]

Well, just finished up CC'ing the block and pistons. I'm a little confused at the numbers cause it seems like my combustion volume is similar to stock after putting everything into the calculator, even though the machine shop says they took .01 off the head.

So... I got 73 CC's for the head. 10.3 CC's for the piston dish. I thought stock combustion chamber volume was 83cc so this seems odd.

That brings me to 9.25:1 which would be right at the max of where I want to be.

My issue is I have heard from others of a stock volume of around 83 cc's and using that number with all the other values being stock, gets you to 9:1. In other words, the overbore to 101mm and engine milling of .008 that both netted me .25 over stock compression is all I ended up with, the head decking didn't come into play somehow.

That makes me think either not as much was taken off by the machine shop, or the stock numbers are actually less than 9:1, which I've read on here from other people doing rebuilds that came up with similar numbers to mine after a milled head that made it look like stock compression was more like 8.8:1.

Anyway, pics below. The liquid under the lexan sheets is vaseline not the alcohol used to measure, and the valves are fully seated. And yes, I filled the burette up to the top, then drained it until it got to zero, no air in the bottom or otherwise.

 

[datdoublea]

I am in a similar dilemma; i may do some volume measurements as well; I went 10:1 forged JE pistons; had 0.022 (0.014 off head; 0.008 off block) taken off my head and block; I went with 0.075 headgasket with the assumption that my deck is added into the gasket height compared to a stock gasket height, hopefully keeping me at around 10:1 if not a touch under. I was eventually planning on a turbo build; with hopefully the primary fuel being E85 for the moderate boost setting, and a few back up tunes and setting including a very low boost 93 setting, and an 87 octane, retard and rich until i can find 93 setting. I guess we'll see what happens when it gets together

 

[satchel]

... never mind. Made some assumptions to that previous post that likely don't apply

 

[scottryana]

On a brand new head I cc'd 74cc's which makes sense if yours has been decked that it would be closer to 73cc

 

[satchel]

That's good to know and I've heard similar things from others that have done this, but I believe those numbers, at least using the calculators I have been, bring the stock ratio down around 8.9:1 instead of the advertised 9:1. I'm pretty confident in my numbers, but I'm also assuming the advertised 9:1 is correct, so there is something going on. Someone is off by .1 to .2. I'm going turbo regardless so I guess I'll just assume I always need to run premium to be safe turbo or not, but still seems odd.

Edited my numbers... guess it's also possible the stock pistons had a little smaller dish than the 101s I'm running.

On a brand new head I cc'd 74cc's which makes sense if yours has been decked that it would be closer to 73cc

 

[satchel]

Can anyone show me where in the fsm it directs you to put in the oil orifice? I believe it should be going in between the head and the block but not seeing the instructions shown at all.

Edit: NM, found it in the block portion.

 

[satchel]

So I did a dumb thing and didn't check an item that I should have. I'm low on time so I had a reputable machine shop turn my block into a short block while they were doing the rest of the machining. Well, I'm pretty far down the path of assembling the engine at this point and noticed that I still have the oil orifice new in the bag. I understand that you can just use the old one and replace if it is clogged, so I'm assuming my shop reused it instead of looking for the new one, but I can't verify that the old one is in place at this point. The only pic I have of the area is the below. Can anyone that is familiar with that orifice tell me if it looks like it is in place? I have no idea how deep that is supposed to be.

 

[890man]

I just finished pulling my head. I can look when i get home this evening.

 

[satchel]

Much appreciated. The more I look at that picture the more I am certain it is still there and the machine shop wrote this morning to verify that their tech normally removes those, cleans the area and reinstalls, so I feel much better about it.

I just finished pulling my head. I can look when i get home this evening.

 

[scottryana]

Looks like it is there to me, but very hard to tell with that pic.

 

[890man]

Here's mine.