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Additives or valve seat?
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Author:  70K1100 [ Thu Jul 21, 2016 5:17 pm ]
Post subject:  Additives or valve seat?

I'm looking at finally making a start on my 1098. But one question I have is whether it is necessary to have the hardened valve seats or can I get away with putting in an additive. The mini will be a weekender.

Author:  drmini in aust [ Thu Jul 21, 2016 6:31 pm ]
Post subject:  Re: Additives or valve seat?

Unless the seats are sunk from wear I would use no inserts and run flash lube additive. Fitting inserts is expensive.
I have had the head off mine 3 or 4 times in the last 20+ years. Valves and seat faces in the head stay shiny. No inserts just flashlube.
This car has been on club plates for 4 years, before that it was used almost daily.
Some racers don't like inserts because they have been known to come loose if engine overheats.

Author:  FNQ [ Thu Jul 21, 2016 6:44 pm ]
Post subject:  Re: Additives or valve seat?

General follow question re inserts

What is a ballpark seat thickness of an insert... can you get thinner ones, or for peace of mind do you say give up a mm of usable valve space..... My thoughts are actually generated by wondering if Group N cars sometime in the (near) Future will be asked to use PULP instead of leaded.... will a 29.7 exhaust valve fit with a 36mm inlet if an insert is taking up space??? and or will that pull the heat closer to the shared edge and cause cracks??? ( just wondering cause /effect )

Author:  Bill B [ Thu Jul 21, 2016 8:52 pm ]
Post subject:  Re: Additives or valve seat?

Ditto Drmini.
I have 1 head converted but the inserts are so junky the must upset airflow.
Been running 2 cars with Flashlube - when I remember to add it - without any problems since unleaded came in.

Author:  70K1100 [ Thu Jul 21, 2016 9:27 pm ]
Post subject:  Re: Additives or valve seat?

Thanks. The head on my FJ Holden was expensive and would like to spend money wisely.

Author:  CPOCSM [ Thu Jul 21, 2016 10:59 pm ]
Post subject:  Re: Additives or valve seat?

^^++1 for the flash lube. Have the mini plumbed with the meter bottle and is set and forget. I got four round trips to Sydney and back from Canberra before having to top up the reservoir(holds 500ml from memory...). Not a single problem with the head and induction side of the mini.

Running the same setup on the GQ patrol TI with dual fuel and 98 ultimate and recently had the head off to replace the exhaust and timing chain...again not a single issue with any of the valves or anything really. 311000km and still looks like brand new in the chambers and tappet chest. Best $17 you can spend on your car.

Author:  gtogreen1969 [ Thu Jul 21, 2016 11:28 pm ]
Post subject:  Re: Additives or valve seat?

I have to admit that i was a bit late to the party using flashlube. For many years after super fuel disappeared i was using a capful of ATF or 2 stroke oil in my tank. When the head came off due to a blown head gasket the valves and seats looked perfect.

Author:  AWOODY [ Fri Jul 22, 2016 3:21 pm ]
Post subject:  Re: Additives or valve seat?

Flashlube is useless despite using it religiously I still ended up with 4 mm valve recession get the inserts done . (now watch the .... fly)

Author:  Drewie [ Fri Jul 22, 2016 10:41 pm ]
Post subject:  Re: Additives or valve seat?

Bit of history on our 1970 Mini K, my mum bought it brand new in 1970, she hardly ever used it and when she passed away I inherited it, car sat untouched for many many years, when my eldest daughter turned 18 she asked could she have the Mini, this was in 1994 so the Mini was 24 years old and had only 11,000 miles on the clock, she used Flashlube, added to the tank when she filled up, she drove the Mini daily for around 16 years and added probably another 100,000 miles before deciding to take it off the road and buy something more modern as a daily, motor wise it was running perfectly, engine has never been apart. So I would say the Flashlube worked fine in that engine.

Author:  69k1100 [ Fri Jul 22, 2016 11:19 pm ]
Post subject:  Re: Additives or valve seat?

http://youtu.be/HPURuJpDNPs

Valves rotate in their seat under normal conditions, it is the friction that wears the seat.

Usually the intake doesn't suffer as it runs cooler than the exhaust. Usual trick is to fit hardened seats on the exhaust.

I guess my first question is what are you actually fitting in terms of head casting? 202, 295.etc. And what are you planning to do to the head? Is it a stock build or are you planning to improve the breathing? Depending on your planned head and valve diameter combo you may not have room for hardened seats due to the proximity of the valves to each other.

A weekend cruiser probably won't suffer that much due to the heat (or lack of) going through the engine. If your planning to flog it when you do drive it then consider fitting hardened seats.

Author:  70K1100 [ Fri Jul 22, 2016 11:33 pm ]
Post subject:  Re: Additives or valve seat?

The head will be a standard valve 295 head with around 9.5:1 compression. It won't be flogged just driven on weekends and some longer runs every now and then.

Author:  Lillee [ Fri Jul 22, 2016 11:37 pm ]
Post subject:  Re: Additives or valve seat?

So in 2006 I put in a Fuelstar (given to me for free so why not). I've run approx 11,000 miles and after Rylstone Classic this year she's coming out for an overhaul. I've run straight unleaded without valve seats the entire time. If you're all interested I'll let you know what the results are...

Does tin actually work? Stay tuned!

Author:  michaelb [ Sat Aug 06, 2016 9:14 pm ]
Post subject:  Re: Additives or valve seat?

I believe Tin is a very good replacement for lead, and it doesn't have the same deadly effect on humans.
Checkout Fuelmate.

Author:  1071 S [ Sun Aug 07, 2016 10:46 am ]
Post subject:  Re: Additives or valve seat?

And I would suggest a good chemistry text that describes how the tin gets dissolved in the fuel.... (You may find this difficult :roll: )

Cheers, Ian

Author:  Lillee [ Sun Aug 07, 2016 7:48 pm ]
Post subject:  Re: Additives or valve seat?

Yeah so I read. I am skeptical too. Will find out soon enough!

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