1.8MM MLS Headgasket. Anyone use these?

[D.J.T.]

For the most part using a thinner HG and raising compression ratio wont mess up too much as long as the motor doesnt knock, dont go crazy though. A stock 1.37mm or the khs 1.2mm will be too thin and will eventually cause detonation. Your best bet is to throw SIP a call or PM and ask him, he has quite a bit of experience with these motors and can recommend you the correct size gasket along with if your a good candidate for a MLS.

Will do ASAP. Thank you!

AND, side note, when you go to retorque, dont loosen all the bolts at once! Make sure you do it one bolt at a time following the proper installation torque pattern.

 

[D.J.T.]

UPDATE. Head Has been torqued to 70 Ft/LBS. pistons don't touch head & valves are clear. Using Fel pro Gasket. Stock Turbo, Stock EVERYTHING. Pictures will upload soon.

 

[FullNelson]

On what size gasket? Just because the pistons dont touch the head doesnt mean your A OK yet

 

[IJ.]

Stock the pistons are 20 thou out of the hole at TDC, you've added another 20 with the block being decked, I'd be getting concerned at this point as while a 7M is a non interfernece engine that quickly changes as you change things and even if the valves don't touch the pistons now what happens when everything is warm and clearences tighten up?

Swapping in the correct thickness HG after machine work is done for many reasons not just compression ratio.

 

[gottadiesel]

Stock the pistons are 20 thou out of the hole at TDC, you've added another 20 with the block being decked, I'd be getting concerned at this point as while a 7M is a non interfernece engine that quickly changes as you change things and even if the valves don't touch the pistons now what happens when everything is warm and clearences tighten up?

Swapping in the correct thickness HG after machine work is done for many reasons not just compression ratio.

While I do agree with you, as I am using a 2.0mm since my head has now been decked twice, to get back to stock would be 1.9x something, so was imo close enough to not have to special order, anyway not my point or question...

Do we have any idea what Toyota would do when you blew a head gasket and warped the head? I guess my question is - in your opinion, is there a viable option outside of going to a MHG of the corrected thickness anytime material has been taken from the head or the block? Which would mean that the only time it was an ok idea to stick with stock HG is if no material has been taken from the motor at all and of course the head it still flat? I am not sure if this will help the OP or not, but a good education perhaps for anyone reading...

 

[D.J.T.]

On what size gasket? Just because the pistons dont touch the head doesnt mean your A OK yet

& a
Stocker for now & thats true. The moment of truth will be when it starts & runs & time. I know im not going to be over revving, peeling off, burnout, etc. itll be a simple daily driver. To go to work & back & Everything is very close where i live.

---------- Post added at 09:39 PM ---------- Previous post was at 09:37 PM ----------

Stock the pistons are 20 thou out of the hole at TDC, you've added another 20 with the block being decked, I'd be getting concerned at this point as while a 7M is a non interfernece engine that quickly changes as you change things and even if the valves don't touch the pistons now what happens when everything is warm and clearences tighten up?

Swapping in the correct thickness HG after machine work is done for many reasons not just compression ratio.

What effects do you believe might take place?

 

[FullNelson]

If its all ready assembled your not gonna want to do what it would take to measure the piston to valve clearance. Basically you take a piece of clay and put it on top of your piston, put the head on the motor and turn the motor over 1 cycle or 720*.

If you have everything on all ready, have you turned your motor over by hand to make sure it does so freely?

 

[D.J.T.]

If its all ready assembled your not gonna want to do what it would take to measure the piston to valve clearance. Basically you take a piece of clay and put it on top of your piston, put the head on the motor and turn the motor over 1 cycle or 720*.

If you have everything on all ready, have you turned your motor over by hand to make sure it does so freely?

Everything is on & yes everything turns freely

 

[D.J.T.]

SHE LIVED! For the moment. I have a massive Water pump leak. New pump required. Im having trouble with the harness though. Many of the harness wires have been cut off & all i have is color wires & have no idea where they go to. Does anyone have the color codes for these wires? Like A/C Switch wire, Oil pressure wire, Temp wire. idk which is which.

 

[gottadiesel]

Im having trouble with the harness though. Many of the harness wires have been cut off & all i have is color wires & have no idea where they go to. Does anyone have the color codes for these wires? Like A/C Switch wire, Oil pressure wire, Temp wire. idk which is which.

Back to a previous question I think I asked you... Do you have a TRSM (Toyota Repair Service Manual) for your year of car? The on-line one that is often posted on this site, is for IIRC a 1989, for 90% of everything it works just fine, but you should have your correct year manual (1987-1988) especially for electrical wiring information. If you do not, PM me with your email and I can send it to you in portions, I have it in a PDF 148mb though. Another option is I utilize a secure FTP site for my business, I could post it up there and give you a temp password to retrieve it. Let me know would be glad to help however I am able.

 

[bombinuass]

gota7mgte this should have everything youll need just read and read and READ http://www.turboninjas.com/mk3supra/

 

[D.J.T.]

Back to a previous question I think I asked you... Do you have a TRSM (Toyota Repair Service Manual) for your year of car? The on-line one that is often posted on this site, is for IIRC a 1989, for 90% of everything it works just fine, but you should have your correct year manual (1987-1988) especially for electrical wiring information. If you do not, PM me with your email and I can send it to you in portions, I have it in a PDF 148mb though. Another option is I utilize a secure FTP site for my business, I could post it up there and give you a temp password to retrieve it. Let me know would be glad to help however I am able.

I HAD it but i needed money so i returned it. Luckily my father has kept some old books since he's a tech & i found a complete diagram of the wiring harness telling what each color wire is & more & yes Online is good. Bomb left a link. Thank you though!!

 

[bombinuass]

Anytime. the cygnus TSRM is for a 90 so i figured id give you one for an 87

 

[D.J.T.]

Anytime. the cygnus TSRM is for a 90 so i figured id give you one for an 87

I had not realized that. Thank you!

 

[gottadiesel]

Anytime. the cygnus TSRM is for a 90 so i figured id give you one for an 87

Yep sure is and that is the only link I had seen on this forum, so thank you for the one you posted earlier... although I do have the 88 version both on pc and hard copy, I have it book-marked for the next time I see someone in need... Thanks

 

[bombinuass]

anytme gottdiesel, i found that TSRM digging through OLD thread. to my surprise it still worked. so i kept it. i think that that one is better. but thats my opionion and both my cars are 86.5 and 87 so it helps me alot

 

[D.J.T.]

update & photos

so far 120 miles & its fine haven't re torqued the head yet. been busy with work & theres no time for that. will try to get it done asap. & i have way more pictures but this is all i post up at the moment

 

[D.J.T.]

Holy crap. Thread update/revival...

almost 6K miles on the rebuild & no BHG!

 

[suprarich]

Just for future reference, the current OEM Toyota head gasket is 1.5 ish mm thick. So you guys need to factor into the equation what the current thickness is and not the the thickness used many years ago.

 

[Poodles]

You're gonna jinx yourself