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Life begins @ 30psi....
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Discussion Starter · #1 ·
Welp I beleive that I royally screwed myself this time, I installed my HKS 272's about 2 weeks ago and today is the first chance that I have had time to check the clearances and everything looks decent except #1 and #6 intake valves. The intake cam seemed more difficult to move then the exhaust as I was setting the cam caps and torqing them down and I feel like now I know why. I guess the 272's combined with a slightly milled head and 1mm oversized valves made it an interference motor.

The spec is .006 - .010 on the intake side but these two cylinders the intake valves are .021 to .030+ and I can almost remove the shim from bucket without depressing the valve. I guess I need to do a leakdown on the damn thing to see whats up. I have no desire to remove the fucking cylinder head but I may not have a choice....

Your input would be appreaciated!

Bob
 

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A while back I thought all 272 cams made it an interference motor, but then I sort of remember KenH or somebody knowledgeable saying it depends on head milling, gasket, etc. Sorry to hear it crashed.
 

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Life begins @ 30psi....
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Discussion Starter · #3 ·
I had a tech from work come over and take a look and see if he could determine anything, after a few minutes and some other checking it does appear that the I bent the intake valves on #1 and #6 cylinder.

Does anyone know if I can remove the cylinder head in the car with ARP head studs?

Thanks,
Bob
 

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Nick 95 6sp said:
A while back I thought all 272 cams made it an interference motor, but then I sort of remember KenH or somebody knowledgeable saying it depends on head milling, gasket, etc. Sorry to hear it crashed.
If your head/block has never been decked, HKS 272s will not make it an interference motor. JUN 272s, the 10.8 mm lift versions, will make it an interference motor, decked surfaces or not, IIRC.

Unfortunately, Bob, from your description, it does sound like bent valves (decked surfaces + 1 mm oversized valves + 272s = interference motor). Sorry for your problems, as I remember from your previous posts how careful you were trying to be to ensure this did not happen. Good luck.

Ken.
 

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vobra46 said:
Does anyone know if I can remove the cylinder head in the car with ARP head studs?

Thanks,
Bob
Yes, but remove the studs before pulling the head (hopefully you have the ones with the allen head on the stud). I'd do a cylinder leakdown test to confirm the diagnosis also and make sure there isn't something else holding the valves open, besides bieng bent (a borescope would be perfect here, looking for a shop rag or something silly).

I'll normally take the crankshaft off of TDC while I'm torquing down the cams if I'm working with an interference engine or am not sure. Then, after the cams are installed and set at TDC for #1, I'll pull the crankshaft backwards to TDC and install the timing belt.

On the bright side, if you haven't run it yet, just some new valves should take care of the problem rather than a whole new head + pistons. This is where one of those kevlar timing belts starts to look like cheap insurance...

=Brian
 

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Life begins @ 30psi....
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Discussion Starter · #6 ·
chevyeater-on-sf said:
Yes, but remove the studs before pulling the head (hopefully you have the ones with the allen head on the stud). I'd do a cylinder leakdown test to confirm the diagnosis also and make sure there isn't something else holding the valves open, besides bieng bent (a borescope would be perfect here, looking for a shop rag or something silly).

I'll normally take the crankshaft off of TDC while I'm torquing down the cams if I'm working with an interference engine or am not sure. Then, after the cams are installed and set at TDC for #1, I'll pull the crankshaft backwards to TDC and install the timing belt.

On the bright side, if you haven't run it yet, just some new valves should take care of the problem rather than a whole new head + pistons. This is where one of those kevlar timing belts starts to look like cheap insurance...

=Brian
Thanks for the input guys, I am kicking myself in the ass right now I can tell you that. The problem was that I was doing the cam install one night after working like 12 hours that day and I was way to tired to have been working on the car but wanted to get these cams in. I am going to do the leak down as a formaility but I know that I am screwed with this situation.

Brian where can I get one of these timing belts that you mentioned? I might as well get one and I know I am going to need atleast 4 1mm ferrerra intake valves at the minimum.

Damn this sucks.

Bob :(
 

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Life begins @ 30psi....
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Discussion Starter · #7 ·
I just went out and checked I do have the allen heads in the top of the studs so atleast I wont have to yank the drivetrain. My wife is so pissed she wants me to sell it and I am almost in agreement :(

Bob
 

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vobra46 said:
Thanks for the input guys, I am kicking myself in the ass right now I can tell you that. The problem was that I was doing the cam install one night after working like 12 hours that day and I was way to tired to have been working on the car but wanted to get these cams in. I am going to do the leak down as a formaility but I know that I am screwed with this situation.

Brian where can I get one of these timing belts that you mentioned? I might as well get one and I know I am going to need atleast 4 1mm ferrerra intake valves at the minimum.

Damn this sucks.

Bob :(
Sorry to hear about all of the extra work you've got to do now. I think it is a part of becoming a true Supra owner to go thru stuff like this though. You're becoming "hardcore", if that is any comfort right now, lol.

About the timing belts, MVP has the Greddy, HKS and PE kevlar timing belts to choose from on thier site. I think most of the other "online stores have a similar selection also. Maybe give Dusty a call and see wich ones are in stock, unless you have a preference.

-Brian
 

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Life begins @ 30psi....
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Discussion Starter · #9 ·
Hardcore is right !!

I bought this car in January and its been down more then its ran. I have already had the drivetrain out of it once already. I have got close to 40K in it now but something about driveing it keeps me coming back for more and more.

Oh well I will let is sit for few days then start tearing it down. Its a relief to know I dont have to yank the motor.

Bob
 

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vobra46 said:
I just went out and checked I do have the allen heads in the top of the studs so atleast I wont have to yank the drivetrain. My wife is so pissed she wants me to sell it and I am almost in agreement :(

Bob

Bob, never make an important decision like this when you are on top of the world or have hit bottom, as in this case. You made a mistake, but that is no reason to sell the car, IMO. Plus, you already know that you made a mistake when you previously sold your black beauty. Get some much needed rest and let your emotions die down (and wifey's) before getting back into it and I think you'll be much better off for it.

GReddy Extreme timing belt (which I have) and PWR are the same, IIRC, so you can't go wrong with either one or the HKS. As chevyeater said, whichever is in stock...

Ken.
 

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Life begins @ 30psi....
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Discussion Starter · #11 ·
I pressurized the cyinders with the cams out and #1 and #6 are leaking air thru the throttle body so I did bend the valves. The exhaust side looks to be fine so I started tearing it down tonight and should have the head off by the weekend. upper intake is off, cams are out, ect ect. I need to find a thin1/2 inch 12pt socket and I will get to the head studs tommorro night.

Bob :(
 

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Wow i'm sorry to hear about your troubles, that truly does sound like a drag. I'm glad you decided not to sell either, but what Ken said was very true and I found that out just recently. I put my car up for sale about 3 weeks ago when I hit a nasty bump in life and I would have definitely cried about it later. Always make important decisions when you're calm :) - looks like you did just that.

As far as having to tear down half the motor again don't sweat it, just enjoy the time you have with it! Lots of people wish they had a Supra to tear down and build up for fun... My dad told me those words when I had just finished completely installing my 6spd, driveshaft, exhaust, etc. and then found out I had installed the clutch disk facing the wrong way. I was going by the Factory Manual but this particular aftermarket clutch went facing backwards... had to drop the tranny again just to flip the clutch disk :faint: It was just me and my girlfriend (yes, she actually crawled under and helped me R&R the tranny!)
 

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KenHenderson said:
Bob, never make an important decision like this when you are on top of the world or have hit bottom, as in this case. You made a mistake, but that is no reason to sell the car, IMO. Plus, you already know that you made a mistake when you previously sold your black beauty. Get some much needed rest and let your emotions die down (and wifey's) before getting back into it and I think you'll be much better off for it.

GReddy Extreme timing belt (which I have) and PWR are the same, IIRC, so you can't go wrong with either one or the HKS. As chevyeater said, whichever is in stock...

Ken.
Would you mind explaining how either of these would help in a situation where the valves are hitting the piston tops?
 

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SupraTT85 said:
Would you mind explaining how either of these would help in a situation where the valves are hitting the piston tops?
I don't see any explanation needed unless you forgot how to "read"


vobra46 said:
Brian where can I get one of these timing belts that you mentioned? I might as well get one and I know I am going to need atleast 4 1mm ferrerra intake valves at the minimum.

Damn this sucks.

Bob :(
 

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ARP studs do not need to be removed for head removal/installation. I just completed this task a few weeks ago and installed the head with the studs in place (also removed it sometime thereafter to check some tolerances).
 

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Nick 95 6sp said:
I don't see any explanation needed unless you forgot how to "read"
There's no need to be an ass :rolleyes: ... the answer wasn't even mentioned in this thread nor was it mentioned in your quote.

SupraTT85: The stronger timing belts are less likely to snap or slip which would cause your valves to meet your pistons (if you've got valve/head/cam work). If you're running stock valves/cams and have no headwork you don't need to worry as the stock engine is non-interference.
 

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I'm wondering if the valve depths were set properly (valve head location in relation to the deck surface).

Keep us updated.
 

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Life begins @ 30psi....
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Discussion Starter · #18 ·
dre99gsx said:
ARP studs do not need to be removed for head removal/installation. I just completed this task a few weeks ago and installed the head with the studs in place (also removed it sometime thereafter to check some tolerances).
The head will slide up and over the studs?
 

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I don't see any explanation needed unless you forgot how to "read"
:ugh2: I understand the concept of the valves hitting the pistons... I was specifically asking how the belts would help in a situation where that has already happened.


There's no need to be an ass ... the answer wasn't even mentioned in this thread nor was it mentioned in your quote.

SupraTT85: The stronger timing belts are less likely to snap or slip which would cause your valves to meet your pistons (if you've got valve/head/cam work). If you're running stock valves/cams and have no headwork you don't need to worry as the stock engine is non-interference.
Thanks :sadance: , I knew that, but I was just confused because I thought maybe it helped in some other way when the valves were hitting.. and maybe the head was jumping up and down or something.
 
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