head was shaved too much off!
- Thread starter tyang82
- Start date
Well, all turbo model Supra's had "Premium Fuel Only" in the fuel filler door lid, or at least mine did. But in response to your question, yes Premium fuel should be used in all turbo/supercharged vehicles for the best safety and power.
Always use the highest octane fuel you have available, there are some places that sell higher than 93 octane which is what we have here in NY. I believe Shell or BP has the highest grade.
There is a place that sells 100 octane or was it 1 something. But I've been pumping regular unleaded for about a year. So I'll switch my gas up as soon as I fire up my baby. I'm thinking of throwing this bad head out now. I hate the sight of it now. More money to spend.
toyotanos;1802730 said:
That is probably the HKS sticker that HKS ships with their aftermarket exhausts.
The stock engine is fine with regular fuel according to my owners manual, however for the OP now that his CR is higher he may want to consider it.
tyang82;1802793 said:
The higher octane is better for your engine as it's a turbo motor. Manufactures like Toyota, Honda and Nissan wont really make a vehicle that will require the higher octane gas all the time but count on the exotic companies to do that.
Don't worry, you will not hurt anything runner higher octane pump gas.
compression has nothing to do with timing. It will let you run bigger cams and spool a larger turbo faster though. Compression is your friend.
the only thing you haver to worry about is per ignition
since you squish and quench have now bean messed up
but I am not sure how much you are off
when I had that mess head combo I had det issue so I had to run 94 only
so I added fuel across the bord with the safc to compansate for the timing and lowered my fuel persure to blance out the added fuel
since you squish and quench have now bean messed up
but I am not sure how much you are off
when I had that mess head combo I had det issue so I had to run 94 only
so I added fuel across the bord with the safc to compansate for the timing and lowered my fuel persure to blance out the added fuel
High compression is good for any piston engine, period, in terms of making more power sooner/effeciently. It's just that it comes with the drawback of increasing your risk of pre-ignition in both forced induction and naturally aspirated applications.
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I'm also from MILW, which machine shop did the work? Did they say why they took that much off? My guess is the head was so warped that it took that much to get it straight but in that case they should have put in a press for a half a day to try to straighten it out a bit before the milled it.
Why not just buy a thicker metal head gasket? If you can figure out what your compression ratio is now then you can figure what head gasket will get you closer to a safe CR. You might be able to get a 2.0mm MHG and get it closer to a 9:0 CR then I say run the head. I had a 7m head milled twice and my CR was at 9:3:1 and I never ran into any issues. I did notice a big gain is spool with it being higher. The only problem I can remember was setting the cam gears in the right spot so when I applied tension to the t-belt the timing marks where aligned.
Why not just buy a thicker metal head gasket? If you can figure out what your compression ratio is now then you can figure what head gasket will get you closer to a safe CR. You might be able to get a 2.0mm MHG and get it closer to a 9:0 CR then I say run the head. I had a 7m head milled twice and my CR was at 9:3:1 and I never ran into any issues. I did notice a big gain is spool with it being higher. The only problem I can remember was setting the cam gears in the right spot so when I applied tension to the t-belt the timing marks where aligned.
.018 thou is .4572mm. If they shaved .008 too much, it's really not the big of a deal. That's only .2mm too much. Really, I wouldn't worry about it. Some engines have more than that in carbon build up on the cylinder head and top of the piston that accounts for taking up a lot more volume than .008 thou extra takes up.
If it was .015 or more too much, THAT would start to be a problem.
Question to the OP: Have you ever had this head shaved before in the past?
If it was .015 or more too much, THAT would start to be a problem.
Question to the OP: Have you ever had this head shaved before in the past?
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