Sandard toyota vs TRD Head gasket

[Rick]

I am in the process of rebuilding my small port 4A-GE for my AE-85 racecar and I have been looking at the different sizes available, TRD head gaskets come in 0.8 and 0.5mm. Can anyone tell me the pros and/or cons of the different sizes, is there is an advantage going for the smaller one?? Or should I stick with the standard size??

Cheers

Rick

[CozmoNz]

Pros.... Increases Compression ratio
Cons... Its Trd..... get ur cash ready .

[ChaosAD]

There is nothing wrong with the standard genuine headgasket, the different sizes are to fine tune the compression ratio and also give a bit more quench/squish.

TRD prices are a lot better than they used to be, my .8mm TRD headgasket set me back $99 but that was a pretty good deal.

[Rick]

There is nothing wrong with the standard genuine headgasket, the different sizes are to fine tune the compression ratio and also give a bit more quench/squish.

TRD prices are a lot better than they used to be, my .8mm TRD headgasket set me back $99 but that was a pretty good deal.

Why did you go for the .8mm over the .5mm??

[Adamal]

The problem with increasing the compression ratio is that you will require a higher octane fuel for it to run properly. It will start to ping otherwise.

An .8mm would give less compression than a .5mm. With a .5mm, you'd probably want to run 98 octane and probably chuck in some octane boost as well. Of course, the compression depends a lot on the pistons etc, but the gasket makes the subtle differences.

[Mr Revhead]

the stock gasket is 1.2mm
you will need to do some maths to work out the ratio change, i dont think its a seriosu amount...


prices of these gaskets has come down a lot lately. under
$100 now.

the TRD one is also a metal one and will take a bit more than the stock one, however the stock one is plenty strong enough for most applications.

[MetalupYoAss]

i looked at this a while ago for my bluetop turbo.. i went with standard thickness toyota one as i dont want to increase compression, if you were na tuning it though you could use the TRD ones to get a bit more performance.. i think the .5mm one only increases compression to around 9.9:1 which is still less than standard 20V compression..

[TRD Man]

Actually, the std gasket used to be 1.0mm. I'd be surprised if this has changed.
We almost always recommend & sell the 0.8mm TRD gasket which we always keep in stock here in Wellington. Using the 0.5mm gasket can require the valve pockets to be machined to avoid contact.

As Warwick has stated, the application of a TRD gasket raises the compression ratio by so little fuel octane is not an issue.

[Mr Revhead]

no stock 4age/4agze 16v gasket is 1.25mm when torqued to spec

[suberimakuri]

as i understand it the change to small port brought about a change from 1 to 1.2mm
i don't know about redtop tvis.

adaml, you will not ping just by changing gasket, it will just run a couple of points leaner... but nothing to worry about.
most people don't even max the timing on their motors either.

metal gasket is nice for reuseability.
$100 is cheap...
BR900 from Appco is about half that. And is the 1.2mm gasket we used on the turbo motors. But if I was building NA motor I'd just get TRD gasket.

If the head and block are good, then 0.5mm is what i'd get. Can always deck head a little so you're sure it'll seal.

[Mr Revhead]

there is a supersession in the the ae82 gasket to the same number as used in the ae92 onwards 16v, the same gasket is used in the 4agzes aswell. its not a change, but a supersession. it has nothing to do with the big port/small port change. the size for that gasket is 1.25mm

[Chickenman]

supersession

Too many of those and you'll get fired

[suberimakuri]

hmm.. i'll have to check acl listings again.

[Mr Revhead]

just a clarification....

ae82 and early aw11 gasket is a different part number, in 9th 87 the aw11 changes to the 42mm crank and the gasket number changes to the later gasket number, for the ae82 and early aw11 it lists a different number which supercedes to the later one

[ChaosAD]

Actually, the std gasket used to be 1.0mm. I'd be surprised if this has changed.
We almost always recommend & sell the 0.8mm TRD gasket which we always keep in stock here in Wellington. Using the 0.5mm gasket can require the valve pockets to be machined to avoid contact.

As Warwick has stated, the application of a TRD gasket raises the compression ratio by so little fuel octane is not an issue.

How much can you take off the head if using a .8mm H/G?

[RedMist]

I've always planed a standard amount from all my heads, wither or not I ran high compression pistons, standard or 310 degree 11mm lift cams, had an additional headwork or ran fuel from 91 to methanol.

from here..................................... to here.... or was that here?

Can't remember if I measured it imperial or metric.

[ChaosAD]

I just put a .8mm head gasket on a bluetop, minimum taken off the head and set the base timing to 10 deg.

Would it be fine to run on 91? or should I run 96 and advance the timing a bit?

I would expect 91 would be fine as I've heard the bluetops are designed to run on 89.

Just out of interest, what would one expect to pay to have a blown headgasket replaced on a bluetop by a mechanic?

[Mr Revhead]

89?? hell no


go 96

[ChaosAD]

I mean 89 octane when STANDARD.
So would 96 give any benefit over 91 octane with the 10 degrees base timing?

[Mr Revhead]

i mean it would not have been made to run on 89 standard....

maybe ethiopia spec ones maybe.....

id think 96 would be ok on 10deg. is this the one with the TRD gasket and planed block/head?