Engine block aluminum vs compacted graphite iron CGI

[saviour stivala]

The 'one piston ring' engines were called qualifying engine only. The only thing that prevented them running in that configuration in the race distance was oil consumption.

[Hoffman900]

The 'one piston ring' engines were called qualifying engine only. The only thing that prevented them running in that configuration in the race distance was oil consumption.

I know and you missed my entire point.

[saviour stivala]

I can't figure up what point/s of yours I missed. Maybe you will explain. Leaving aside the Piston-pins issues the other racing categories you said run into, this because I never came upon such issues being encountered in F1, Running the F1 engines with just one piston ring blow-by was never mentioned as a problem encountered. could be that crankcase oil/air scavenging in F1 was good enough to cope with the extra blow-by.

[etusch]

Nissan Patents Engine Block Made Of Carbon Fiber

https://www.msn.com/en-us/news/technolo ... 70#image=1

[Setitup]

Because a F1 engine is a stressed member cast iron cracks

Cast iron blocks are used a stressed members as well, in tractors of all things!

The Ferrari F50 uses a cast iron block as a stressed member because aluminum was not strong enough. Why didn't they go with an aluminum block? It was not strong enough.

Which road cars or high performance sports cars use aluminum as a stressed member and how much does it cost and how long does it last long term compared to using grey cast iron or compacted graphite iron CGI ?

I'd like to see the long term results of street racers and drag racers using the Toyota Supra and Dodge Viper iron blocks vs if they were to use aluminum blocks. Some of these cars are producing over 2,000 hp with twin turbo on repeated runs.

The viper is an all aluminum block

[Alex077]

When you start burning stuff on top of the piston it gets hot, grows and doesn't fit the cylinder any more.+

Absolutely,
when combustion residues accumulate on top of the piston, the heat generated causes expansion. This can lead to a situation where the piston no longer fits properly within the cylinder, resulting in reduced engine efficiency and potentially severe damage if left unaddressed.GB whatsapp Apk

[AR3-GP]

The 'one piston ring' engines were called qualifying engine only. The only thing that prevented them running in that configuration in the race distance was oil consumption.

That would have been desirable from '14-'17

[saviour stivala]

The 'one piston ring' engines were called qualifying engine only. The only thing that prevented them running in that configuration in the race distance was oil consumption.

That would have been desirable from '14-'17

If interested in the more detailed technical maters please refer to ''Qualifying 'only' specials (engine) - Gptechnical page 1 of 26 Sept 2019 05:34.

[coaster]

Would anybody have a thread link to a discussion about iron main caps on alloy blocks?
Chevy LS uses this, has this arrangement ever being problematic?

[Greg Locock]

You can make a stab at that knowing the coefficient of expansion of the metals and the oil temp, which is unlikely to exceed 150 deg C.

[Tommy Cookers]

.... iron main caps on alloy blocks ....Chevy LS uses this, has this arrangement ever being problematic?

well ....
billet LS blocks are made from 6061 alloy ....
unlike the usual cast block alloy (357) it has little silicon and so has greater coefficient of expansion

390 alloy (for pistons) has very high silicon content and so unusually low expansion - but isn't used for blocks
presumably GM knew what they were doing

these lowish coefficients of expansion increase a lot with temperature

[Martin Keene]

Would anybody have a thread link to a discussion about iron main caps on alloy blocks?
Chevy LS uses this, has this arrangement ever being problematic?

I would imagine every road car aluminium engine block uses iron main caps, aluminium is just not going to provide the durability against the combustion loads. What are you thinking might be the problem with this arrangement?

[coaster]

I often see turbo versions splitting the block along the line of the main bolts, i cant help but wonder if a heat differential played small part in the failure as one fights the other with expansion the bolt line becomes the weak point.

The Ferrari F40 turbo engine uses alloy main caps with only 2 bolts, this kind of failure is unheard of, but then we are talking turbos so whoever controls the wastegate is going to be failure point really, I guess.

[Rodak]

.... iron main caps on alloy blocks ....Chevy LS uses this, has this arrangement ever being problematic?

well ....
billet LS blocks are made from 6061 alloy ....
unlike the usual cast block alloy (357) it has little silicon and so has greater coefficient of expansion

390 alloy (for pistons) has very high silicon content and so unusually low expansion - but isn't used for blocks
presumably GM knew what they were doing

these lowish coefficients of expansion increase a lot with temperature

Well, I'm curious about the claim of the coefficient changing 'a lot' with temperature. Everything I see agrees that it's not linear and does increase with temperature although the changes are minor; we're dealing with pretty low temperatures in an internal combustion engine. Do you have a source for this? I'd appreciate a reference.

[Greg Locock]

There are step changes in density when solids go through a phase change, which would give a very non linear COTE, I find it hard to believe this is an issue for blocks, heads, or pistons.