Stainless steel head spacer boost levels?

[Red October]

Im doing the head spacer on my c1j next week, 1mm stainless to take my overall minus the gasket to 73.66mm.

Ive picked up a application/fitment technique off VW forum and there are cars running in excess of 20psi featured on there. Question is how much boost is acceptable on a c1j before i encounter issues?

Ive chosen blue hylomar as my gasket seal agent and am confident it will do the job.
The method ive chosen is:
1 Put MLS gasket set on block and align.
2 Put 1mm SS space on top of gasket and line up.
3 Using a fine brush apply the hylomar evenly all over the SS spacer.
4 Put on head and torque.

Now...........

Should my tourqe levels be the same for the bolts to achieve the right crush?
Do i run it in at 10psi the n keep uppin and upping the boost levels?
Can anyone technical spot any potential pitfalls?

Im putting a lot of faith in a piece of steel and a £10 tube of blue paste considering it could destroy a brand new un-run rebuild. With me fitting the nodiz mappable ign ill have to run the car in on the base map and after a ton go see scoff and see hof far i dare go.

ANY input is appreciated.......

[michael tierney]

personnally,i'd go with 2 gaskits

[stu21t]

Surely the worst that can happen is the blue paste gets squeezed out and then leaks, it won't cause any engine damage as such.
You will just have to try another way of sealing.

[Sid Dawn]

I agree with stu21t..

only way it could damage is if it overheats...as it would when seal goes...and them guys at blue hylomar are pritty sure it is well up to much more than a 5 Turbo..

like you say Ash..take it steady to start with run it in then slowly boost it up...

[Red October]

personnally,i'd go with 2 gaskits

Ive done a good 8-10 hours of technical research into this so far Michael and there are a minority that do the two gasket technique but its less reliable than the single version. Also id be taking it past 73.66 adding anothe 1.7 or 1.9mm gasket on top taking it up to 75.56 (again im unsure of these results).

The hlomar has been proven with my technique above to high pressures. I spoke to Chris at hlomar uk technical support and he reckoned their product has done some big diesels with huge amounts of pressure. He offered his advice and genuinly stated that they had never had a failed gasket using said method.

[Markey Mark (BD)]

If you want to raise the compression ratio back up due to an over skimmed head why not just modify the combustion chamber?
I have never liked the idea of spacer plates or 2 headgaskets

With your idea, if the plate isn't exactly flat it'll leak and worse case it could leak water into the oil, oil into water or either into the cylinders

[michael tierney]

run with 1 so but u'll hav to hav everything spottless for a good bond and try nnot to hav sqeeze out going into the chambers

[SCHWARTZ]

I agree with mark here spend the money you save on mls gasket and have the chambers taken out and use a 1.9mm gasket and have no comebacks.

[Mart]

If you want to raise the compression ratio back up due to an over skimmed head why not just modify the combustion chamber?

^ This.

Simply open up/out the squish area.

J.D

Alternatively, if you can keep the det' in check (which you should be able to, seeing as you're running NoDiz), then I'd personally stick with the higher c/r.

[Red October]

Hmmmmmmmm.........

Doing it that way would seem a lot easier. Does anyone have any info or pics of said area that can be de-meated? Cheers.

[Markey Mark (BD)]

Hmmmmmmmm.........

Doing it that way would seem a lot easier. Does anyone have any info or pics of said area that can be de-meated? Cheers.

Normally they take the material out the flat area of the combustion chamber so it starts to look abit more round rather than rectangle (if see what I mean)
It will be easiest and safest way to do it i'd say

[GTphil]

Normally they take the material out the flat area of the combustion chamber so it starts to look abit more round rather than rectangle (if see what I mean)
It will be easiest and safest way to do it i'd say

That's exactly what the engineers have just done to my brothers cylinder head it was 72.5mm i think maybe less, he also runs low comp pistons, feels the same as my lump off boost, i have a good half a mm more meat on my cylinder head than his and i also use low comp dished pistons, yet to put some boost through my bro's engine tho

[Red October]

That's exactly what the engineers have just done to my brothers cylinder head it was 72.5mm i think maybe he also runs low comp pistons, feels the same as my lump off boost, i have a good half a mm more meat on my cylinder head than his and i also use low comp dished pistons, yet to put some boost through my bro's engine tho

Im going to run standard tarabusi pistons and liners, 1.9mm MLS gasket and the head currently stands at 72.66mm. Im aiming for + 235bhp tbh.

[Kris M]

Why in particular are you going for the MLS gasket?

[Markey Mark (BD)]

Im going to run standard tarabusi pistons and liners, 1.9mm MLS gasket and the head currently stands at 72.66mm. Im aiming for + 235bhp tbh.

I'd get the head machined out abit to bring comp down abit then fit a normal blue seal gasket, that'll hold together well enough

[r5_scotty]

blue seal meiller gasket i belive

[Tony Walker]

If you have mappable ignition then i cant see why you wouldnt want to have a higher compression ratio? more compression=more power at lower boost levels.
The only reason people try to stick at the original compression is because of the standard renix ignition map and the years of trial and error tuning to roughly be ok with this renix.... when using programable ignition timing then you will just get it mapped to your unique engine regardless of compression values.

[Red October]

Why in particular are you going for the MLS gasket?

No faith in the engine from previous experiances as ive been fighting fires so to speak with gremlins, and HG has failed twice. Now ive gone balls out on the motor I might as well on the gasket. I know the implications.

[Red October]

I'd get the head machined out abit to bring comp down abit then fit a normal blue seal gasket, that'll hold together well enough

Probably whats going to happen, im going down the machinists tomorrow to check on the guide enlargement for the bigger competition valves so ill see what they say then. MLS has been purchased already so its going on.

[Red October]

If you have mappable ignition then i cant see why you wouldnt want to have a higher compression ratio? more compression=more power at lower boost levels.
The only reason people try to stick at the original compression is because of the standard renix ignition map and the years of trial and error tuning to roughly be ok with this renix.... when using programable ignition timing then you will just get it mapped to your unique engine regardless of compression values.

I see what your saying tony. Id like to run decent boost so I automatically assumed getting back to the design comp would compliment the upgrades. So 72.66 isnt bad or good?

[SCHWARTZ]

If you're going through head gaskets then most prob fueling isn't right, putting a more expensive/stronger gasket on just means something else more problematic will let go first. A standard gasket is more than up to the job let alone the 1.9mm mellior ones.

[Red October]

If you're going through head gaskets then most prob fueling isn't right, putting a more expensive/stronger gasket on just means something else more problematic will let go first. A standard gasket is more than up to the job let alone the 1.9mm mellior ones.

Car was full of gremlins and cracks not obvious stuff and ive been pissing money away right left and center on knock on problems after the inital catalyst is repaired. It was, or is time to "go hard or go home" as like ive already said nearly all new parts, upgrades, enlargements and systems its been done before I know but imho the motor will be a bullet proof build with a gasket to match.

[groky]

Don't mean to butt in and test anyone's c1j expertise but with the head already being skimmed once or twice given the measurement would it not be best to skim the pistons that way will give the head more life giving more for the valves I know we only talking 1mm but maens the head could be skimmed again if needed. Andnot scrapped.

[groky]

Don't mean to butt in and test anyone's c1j expertise but with the head already being skimmed once or twice given the measurement would it not be best to skim the pistons that way will give the head more life giving more room for the valves I know we only talking 1mm but maens the head could be skimmed again if needed. Andnot scrapped.

[Scoff]

Whatever spacer plate you make should incorporate the squish area too. IE not round holes.

I'm not a fan of cutting out the quench areas, I always had best results with that left in and better still with a 1mm gasket to really bring the squish up. Compression should be standard or slightly raised, they're horrible when CR is low. I don't know why anyone would want low CR. You need a lot of timing to get any real output and to keep EGT in order. It kills off-boost response and ecconomy.

Lots of guys with other engines use alloy spacers and just a thin layer of sealent to bond it to the head, not too dissimilar to a copper gasket. I'm not sure how well stainless will work ? I guess fine enough if it and the head are very flat and smooth. The worst that will happen is pressurisation of coolant or water / oil mixing.

My last and best C1J ran 8.3:1, some ignition retard and about 27psi I think. I used a 1.4 NA gasket (1mm) to improve squish and bring the CR up. I can't remember if pistons were flat top, I think they were. That could do 116mph in the 1/4m, so maybe about 260hp. I found that more CR was better than more timing. And more squish was better than less squish.

[groky]

......

[Red October]

A lot to take in. Scoff what would you do in my position considering your history in this topic?

[Sid Dawn]

Whatever spacer plate you make should incorporate the squish area too. IE not round holes.

I'm not a fan of cutting out the quench areas, I always had best results with that left in and better still with a 1mm gasket to really bring the squish up. Compression should be standard or slightly raised, they're horrible when CR is low. I don't know why anyone would want low CR. You need a lot of timing to get any real output and to keep EGT in order. It kills off-boost response and ecconomy.

Lots of guys with other engines use alloy spacers and just a thin layer of sealent to bond it to the head, not too dissimilar to a copper gasket. I'm not sure how well stainless will work ? I guess fine enough if it and the head are very flat and smooth. The worst that will happen is pressurisation of coolant or water / oil mixing.

My last and best C1J ran 8.3:1, some ignition retard and about 27psi I think. I used a 1.4 NA gasket (1mm) to improve squish and bring the CR up. I can't remember if pistons were flat top, I think they were. That could do 116mph in the 1/4m, so maybe about 260hp. I found that more CR was better than more timing. And more squish was better than less squish.

my spacer will keep the flats in...not shaped to bore...

[Scoff]

Thats nice

[Scoff]

A lot to take in. Scoff what would you do in my position considering your history in this topic?

Sorry Red I only read the most recent few posts

[TNT ANDY]

I have nothing to add to this, but I suspect like many others I'm watching with interest. This is a fascinating topic, hope all goes well.

[Red October]

Skimmed the tarabusis by a mm want the comp at seven and half to one. Job done as there is another way you know!

[BluntyR5GTT]

popped around gt earlier pal think mr tweedie is looking forward to getting stuck in on your engine

[Red October]

popped around gt earlier pal think mr tweedie is looking forward to getting stuck in on your engine

Chopmping at the bit! Hes on it tomorrow. Been down today me sen and done the simulations of the different comp ratios on the pc, marks selected one that looks like a winner with the new setup. Looking at having 2 modes with the boost and 2 maps, one going as far as we can 240+ hopefully but marks concerned about rod strength and the other settings going be about 210-220 17psi round town lmao

[gttjames]

my spacer will keep the flats in...not shaped to bore...

obviously that will only work on skimmed heads, as from oe they look like this



i did have a picture of my head which has had the squish area took out slightly to get close to standard cr, but cant find it