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I'm wondering which head gasket to go for?
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So
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Cheers,
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Paul.
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Paul R wrote:Hi,
I'm wondering which head gasket to go for?My car has a rev1 engine(block and head) and It will be running with a rev3 manifold and Ct20 turbo with de-cat pipe.
![]()
I'm planning on running about 1bar.
So- which head gasket should I go for?
Anyone got prices and places to get one from?
I dont want to alter the cmpression ratio if I can help it.
Cheers,
Paul.
gtschris.com wrote:Paul R wrote:Hi,
I'm wondering which head gasket to go for?My car has a rev1 engine(block and head) and It will be running with a rev3 manifold and Ct20 turbo with de-cat pipe.
![]()
I'm planning on running about 1bar.
So- which head gasket should I go for?
Anyone got prices and places to get one from?
I dont want to alter the cmpression ratio if I can help it.
Cheers,
Paul.
Paul,
to keep compression ratio the same you want a 1.0mm multi steal layer gasket.
I sell cosmetic MSL gaskets and will have 1.0mm in stock soon.
You can use a Toyota rev3 gasket but you need to drill a couple of hole in it(which my personal feel is this is not a very good idea).
PS- the 8 stud rev3 exhaust manifold will not fir your rev1 7 stud head, but the ct20b bolts right upto the rev1 exhaust manifold.
regards,
chris
Paul R wrote:gtschris.com wrote:Paul R wrote:Hi,
I'm wondering which head gasket to go for?My car has a rev1 engine(block and head) and It will be running with a rev3 manifold and Ct20 turbo with de-cat pipe.
![]()
I'm planning on running about 1bar.
So- which head gasket should I go for?
Anyone got prices and places to get one from?
I dont want to alter the cmpression ratio if I can help it.
Cheers,
Paul.
Paul,
to keep compression ratio the same you want a 1.0mm multi steal layer gasket.
I sell cosmetic MSL gaskets and will have 1.0mm in stock soon.
You can use a Toyota rev3 gasket but you need to drill a couple of hole in it(which my personal feel is this is not a very good idea).
PS- the 8 stud rev3 exhaust manifold will not fir your rev1 7 stud head, but the ct20b bolts right upto the rev1 exhaust manifold.
regards,
chris
Ok, cheers.
What difference would I see if I fitted a 1.1mm gasket and is it a good idea??
When you saythat a rev3 manifold wont fit a rev1 head, do you mean it wont seal properly or what?
I have a rev3 manifold on my car already!as far as I can see, the rev3 manifold just has two extra stud holes
- that arent used on my car, appart from that, they are the same??
Cheers,
Paul.
gtschris.com wrote:Paul R wrote:gtschris.com wrote:
Paul,
to keep compression ratio the same you want a 1.0mm multi steal layer gasket.
I sell cosmetic MSL gaskets and will have 1.0mm in stock soon.
You can use a Toyota rev3 gasket but you need to drill a couple of hole in it(which my personal feel is this is not a very good idea).
PS- the 8 stud rev3 exhaust manifold will not fir your rev1 7 stud head, but the ct20b bolts right upto the rev1 exhaust manifold.
regards,
chris
Ok, cheers.
What difference would I see if I fitted a 1.1mm gasket and is it a good idea??
When you saythat a rev3 manifold wont fit a rev1 head, do you mean it wont seal properly or what?
I have a rev3 manifold on my car already!as far as I can see, the rev3 manifold just has two extra stud holes
- that arent used on my car, appart from that, they are the same??
Cheers,
Paul.
if its got 2 extra stud holes unused it be a rev2 manifold, the port are in the same play rev1/2 but rev3 posts are diffrent shape and position thus a 8 stud rev3 manifold will not go on a rev1/2
Elmo Owen wrote:GTSchris can supply good Cometic 1.4mm gaskets
You wouldn't notice the comp.ratio change
'that much' when driving it and it would save having to change it or lower the chances of Det.
when you dicide to tune it later on.
Thick HG= Insurance for Pistons when they cost
£400 a set.
just my 2p
Paul R wrote:Elmo Owen wrote:GTSchris can supply good Cometic 1.4mm gaskets
You wouldn't notice the comp.ratio change
'that much' when driving it and it would save having to change it or lower the chances of Det.
when you dicide to tune it later on.
Thick HG= Insurance for Pistons when they cost
£400 a set.
just my 2p
hmm..
.
!
Is there no down side to fitting a thicker head gasket?
Has any one else had any experience of this?
MR2Mania wrote:ISTR that the stock Rev1/2 HG is about 1.1-1.2mm? I know for sure that the stock Rev3 one is 1.05mm uncompressed, 1.0mm compressed.![]()
Changing the CR with a thicker HG is WRONG! Sorry, but it affects your squish(what goes on in your combustion chambers as the charge is compressed before ignition).
The only proper way to change CR is to make changes to the combustion chambers and different piston crown design, IMHO.
For a Rev1/2, one of the best AFFORDABLE gaskets is a TTE 1.2mm version, although they're not that easy to get hold of.
Paul R wrote:So a 1.1mm head gasket would be a fair bet then??
Reduce detonation slightly with hardly any loss in fuel economy?
Cheers,
Paul.
gtschris.com wrote:I would have to disagree with mr2mania, droping the c/r on a rev1/2 with a thicker h/g is good news.![]()
The rev1/2 runs a fairly high compression ratio of 8.8:1 from the factory
(t3 cosworths run 8.0:1 stock) that coupled with a JDM ecu mapped for high octane jap fuel
+ a factory intercooler that heat soak at low speeds
= prime candidate for detonation problems, anything you can do to help avoid detonation is a bonus when running above standard boost levels.
![]()
MR2Mania wrote:gtschris.com wrote:I would have to disagree with mr2mania, droping the c/r on a rev1/2 with a thicker h/g is good news.![]()
The rev1/2 runs a fairly high compression ratio of 8.8:1 from the factory
(t3 cosworths run 8.0:1 stock) that coupled with a JDM ecu mapped for high octane jap fuel
+ a factory intercooler that heat soak at low speeds
= prime candidate for detonation problems, anything you can do to help avoid detonation is a bonus when running above standard boost levels.
![]()
That's your prerogative to disagree mate, but let me throw a few facts your way:
* Why is BenF's now less economical off boost, etc, since his thicker HG? Maybe his VE has been reduced, or that combustion is not as complete as before?
* Evos have 8.8:1 CR as standard, and yet you still hear of them running 2bar plus of boost.
And they spool pretty well!
* Low CRs is an old Cosworth line of thinking.
How many other tuned 2 litre turbos run low CRs? Again, look at what some of the Evo boys are achieving, some with RAISED CRs, and then come tell me that dropping the CR is the way to go.
Or look at what other top Jap tuners are doing.
You'll actually find it difficult to get a straight answer from most top tuners when you ask them what the CR is, because they don't want you to know that they've actually raised the CR.
Do you actually know what squish is, and how a thicker HG can affect it?
Incidentally, I've RAISED the CR on my own Rev3 build, and I'm glad I did.![]()
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MR2Mania wrote:gtschris.com wrote:I would have to disagree with mr2mania, droping the c/r on a rev1/2 with a thicker h/g is good news.![]()
The rev1/2 runs a fairly high compression ratio of 8.8:1 from the factory
(t3 cosworths run 8.0:1 stock) that coupled with a JDM ecu mapped for high octane jap fuel
+ a factory intercooler that heat soak at low speeds
= prime candidate for detonation problems, anything you can do to help avoid detonation is a bonus when running above standard boost levels.
![]()
That's your prerogative to disagree mate, but let me throw a few facts your way:
* Why is BenF's now less economical off boost, etc, since his thicker HG? Maybe his VE has been reduced, or that combustion is not as complete as before?
* Evos have 8.8:1 CR as standard, and yet you still hear of them running 2bar plus of boost.
And they spool pretty well!
* Low CRs is an old Cosworth line of thinking.
How many other tuned 2 litre turbos run low CRs? Again, look at what some of the Evo boys are achieving, some with RAISED CRs, and then come tell me that dropping the CR is the way to go.
Or look at what other top Jap tuners are doing.
You'll actually find it difficult to get a straight answer from most top tuners when you ask them what the CR is, because they don't want you to know that they've actually raised the CR.
Do you actually know what squish is, and how a thicker HG can affect it?
Incidentally, I've RAISED the CR on my own Rev3 build, and I'm glad I did.![]()
![]()
Jimbob wrote:Looking at piston comp ratios and HG thicknesses its soooo confusing.![]()
Considering JE seem to be a decent manufacturer of pistons but generally have a high CR.Would it be an idea if using Higher CR pistons to then use a Thicker HG to lower it again?
I have to say I thought the thinner any gasket the better in a pure engineering sense.Although HG's open up a whole new ballgame.
Can anyone tell me the standard CR of a Rev2? I would like to get slightly lower CR pistons, and keep the HG the same if possible, or use a slightly thicker HG if worst somes to worst
Cheers
gtschris.com wrote:
I am reading a great book at the moment(maximum boost by cork bell) I found a paragraph that sums it up .