Head gasket choice question for modified 944 turbo

[Dan944t]

hi guys,

the time has finally come round to me having a few weeks to weeks to begin my full engine rebuild , and this will be one of a few question I need to ask.

i ran a cometic 3 layered gasket before i Pulled the engine to bits and didn’t run that for long.

Im thinking wide fire or can I get away with normal victor rienze ???

not had the car in Dyno yet but I would say it’s around the 350 + mark and this time have a few more lightened racing parts which I was forced to purchase ?? so I would like to think it may be nearer the 400 mark but we will see once it’s up and running and nicely run in as I can’t wait to get it on a Dyno.

i am running 1.2 bar of boost 18 psi 38mm TIAL dual port wastegate JMG custom chip set manual boost controller .55 lb injectors, 3bar fuel preasure reg, 993 blow off valve uprated fuel pump And few other bits and pieces .

I’ve had my cylinders milled out and thicker custom wet liners made up and fitted and racing IASA pistons and rings and custom made rods, lightened flywheel, crank scraper and everything balanced so didn’t know if it has to be widefire with my mods as a minimum or can I run the normal gasket or is it not worth it long term ect.

Any help appreciated
thanks
daniel ??

 

[Cater_Racer]

hi guys,

the time has finally come round to me having a few weeks to weeks to begin my full engine rebuild , and this will be one of a few question I need to ask.

i ran a cometic 3 layered gasket before i Pulled the engine to bits and didn’t run that for long.

Im thinking wide fire or can I get away with normal victor rienze ???

not had the car in Dyno yet but I would say it’s around the 350 + mark and this time have a few more lightened racing parts which I was forced to purchase ?? so I would like to think it may be nearer the 400 mark but we will see once it’s up and running and nicely run in as I can’t wait to get it on a Dyno.

i am running 1.2 bar of boost 18 psi 38mm TIAL dual port wastegate JMG custom chip set manual boost controller .55 lb injectors, 3bar fuel preasure reg, 993 blow off valve uprated fuel pump And few other bits and pieces .

I’ve had my cylinders milled out and thicker custom wet liners made up and fitted and racing IASA pistons and rings and custom made rods, lightened flywheel, crank scraper and everything balanced so didn’t know if it has to be widefire with my mods as a minimum or can I run the normal gasket or is it not worth it long term ect.

Any help appreciated
thanks
daniel ??

What are you using the car for???

Road/Race/ Track day?

 

[PSH]

Dan...cometic only....I've blown both standard and wide fire gaskets...never blown a cometic multi layer.....IMHO it's a no brainer..

Pete

 

[Dan944t]

Hi cater racer, I will be using the car only for road use . Maybe one day may take it on the track but that’s not the intention it’s just for weekend pleasure .

hi Pete,

ive finally got here and can’t wait to start! I was wondering if I should go back to the cometic 3 layered.? Now Promax has gone where do you think I can find one in the U.K.?

thanks
daniel

 

[PSH]

hmm...not sure about that Dan..I got mine from LR in the US, they were the only supplier who had stock of the thickness/bore size that I needed. Don't forget to measure the wear tab on the head to see which thickness you need, you'll require the amount that Serdi machined off too. After the machine work that you've had done I would expect you to need a thicker HG.. IIRC my HG may be more than 3 layers now, I just can't remember?

Pete

 

[Dan944t]

How do you work those measurements pete do you remember?
I know that tab as I tried to do it before but can’t remember now, is it explained with specs in the Haynes manual? or I have a technical book coming from Frazier parts with all tolerances it may be in there but may not be.

i did get serdi to check it for me way back when at the very beginning and also asked the question but cant actually remember if I got an answer as they ended up doing so much custom work for me in the end that it got forgotten.

daniel

 

[PSH]

.download the Porsche manual so you can see where to measure, http://www.uriarte.dk/por...manuals/vol1.pdf it's all in there, page 15-16A. You will need to ask Serdi how much they removed when decking the block. 24mm is the measure for a new cylinder head +- 0.1mm tolerance...

Pete

 

[Dan944t]

ta Mate,

ill look it up just annoying that ill have to wait wait ages for it to turn up if it means I can only get it from LR over in the states ?? Reason being that I can’t find my head gasket set nor my oil cooler gasket set so Ive been on the phone all day to porsche ordering each and every bit I need which sure does add up and I now need the gasket and a few other bits.

And let me tell you its so dangerous the porsche breakdown diagram sent to you as I was just saying yep yep yep I’ll have a new one of those while I’m at it and it went on and on and on and added up to a whopping £500 and I’ve still got to ey the head gasket manifold studs , bolts and gaskets, water gaskets, cam gaskets ect ect

I even end d up ordering a new oil filler cap just becuase I thought well I would like it really yellow! breakdown catalauges are dangerous!

on another quick question, would you or anyone know where I can buy all my water pipes in red other than from China or linsey racing? I would like to renew them as I’m at it and would love them to match the red of the car even though up to now have kept everything black but as I’ve painted the cam tower and manifold and intercooler pipes red I thought I may as well change them for red.

if I end up having to buy the head gasket from LR than I will obviously buy the pipes from there as they do do them . ( but again that will be dangerous!)

atb
daniel

 

[PSH]

Hi Dan...sorry for late reply....I don't know of anywhere other than Lindsey for silicon water pipes...I wish there was better support for our cars here in the UK..

Pete

 

[Dan944t]

Hi Pete,

ni probs mate ?? I slept in it last night and had a look on LR site and they seem to have taken away the medium water pipe set it seems ? And only seem to do the full pipe kit which is allot of money and includes vaccum lines ect that I don’t need as I have uprated hard push fit pipes fitted by JMG. I was thinking maybe just replace with originals and spend the extra money on maybe braided fuel rail pipes instead?

im still on the search for the mls in this country but not going to hold my breath ?

i just need to order stuff soon as I can.

atb
daniel

 

[PSH]

Try Burton Power, they have a large range listed, in fact, they have one to match mine with a 66 thou, 5 layer thick, 100.5mm bore gasket...the thing is though I think that they order direct from the states to fulfill any UK orders.. I say this as they state a 4-5 week lead time? Check out their site. http://www.burtonpower.com/parts-by-brand/brands-c-to-d/cometic.html?engine_manuf=710

Pete

 

[Dan944t]

Cheers Pete,
i did actually find these yesterday also and decided to look elsewhere becuase of the lead time? In hindsight I should have thought about the mls and measuring the head ect sooner but life’s so hectic with small kids and a big family that it just fly by and only now have I come across an opportunity to start thinking of taking a bit of time out from work to start the build, not realising I was going to run into this gasket situation but should have thought about it last year ??

anyhow today I am calling porshe again to order a few more bits and to enquiry about replacing the water pipes and cost. Also I am going to get my head around finding out the exact thickness I am going to need for the gasket from the head measurement ??

 

[PSH]

taking another look it seems they have a 40 thou 100.5mm in stock....I guess it depends how lucky you are if this fits? 100.5 is the next size up after rebore...IIRC you sleeved yours which may retain the 100mm bore?

 

[Dan944t]

Hi Pete,

just had a measure of the bores and mine are 100.5mm internal and 121.2mm external walls are 10.7mm thick

not done the measurements in the head yet?

the link didn’t work that you sent on the manual stuff but I shall look it up ??

 

[PSH]

re-measuring the head...there's a tab that sticks out the front and possibly also the back of the head, place the head on a flat surface and using a depth gauge measure the height of the tab from the bottom of the head. Since you are measuring in tenths of a millimeter you can't measure this distance using a rule.

Pete

 

[Dan944t]

Cheers Pete I’m going to get the depth gauge out right now and will Report back my findings.

hopefully these links work, here’s a quick pic of the new thick liners

https://imgur.com/a/LORaP4Q

 

[PSH]

looking good Dan...I have zero experience with sleeves ..the engineering side of my Brain would question possible hot spots due to water passage being blocked between the cylinders..I would expect hotspots due to this but I trust Serdi in what they do, the thicker walls I would guess help reduce heat somewhat anyway. Looks great ....clearly, the block has been machined to get the sleeves the same height so you will need to ask Serdi by how much?
I look forward to seeing you get the engine back together...do download the Porsche manual as IMHO you can't build these engines without the info contained within.

cheers

Pete

 

[Eldavo]

I got a set of Chinese silicon coolant hoses in red and apart from a few little trimming issues where they where a tad thicker or longer I’ve been happy with them.

 

[Dan944t]

Yes I agree with you, when I saw they were almost touching I thought the same but trust they know what there doing, they say that the IASA piston and rings are a perfect match material wise and that came a discussion with Woodford who make the sleeves, that was before I bought it had anything done.

just off to an appointment with my wife as were expecting a our 3rd child so on my arrival will be doing that measurement and also need t give John a call.

daniel

 

[Dan944t]

I got a set of Chinese silicon coolant hoses in red and apart from a few little trimming issues where they where a tad thicker or longer I’ve been happy with them.

Hi Eldavo,

would you mind telling me where you bought them from, and how much they were? Also how long have you run them for

I shall give porsche a quick call later when I’m home and find out how much the originals will cost but I’m sure they will be very costly as it all adds up quick

atb
daniel