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I've watched a basic videos on how a petrol car engine works. It would be good to find some more in depth stuff. I plan to do a few builds in the future and I would like to know how I can get hands on instead of sending it into a shop all the time.

On 05/06/2025 at 2:31 PM, PranK said:

 

What 'in depth' are you looking for ?

 

Exactly how each part works and how they all work together to make the engine function. That's all I'd need to do a basic build. Maybe how forced induction works.

I probably need to learn some of the maths behind it all as well.

3 hours ago, RA708 said:

I plan to do a few builds in the future

What are you planning to do specifically? 

3 hours ago, RA708 said:

I probably need to learn some of the maths behind it all as well.

I would be very surprised if you need to learn any math for these 'few builds' you have planned for the future.

On 05/06/2025 at 5:57 PM, Murray_Calavera said:

What are you planning to do specifically? 

I would be very surprised if you need to learn any math for these 'few builds' you have planned for the future.

I have a terrible idea to twin charge a BNR34. Or an r35. So compression ratios and how they work as well as what certain measurements do for an engine (bore that sorta stuff). I will probably upgrade what ever engine it is with forged rods and pistons and some other strength upgrades.

3 minutes ago, RA708 said:

I have a terrible idea to twin charge a BNR34. Or an r35. So compression ratios and how they work as well as what certain measurements do for an engine (bore that sorta stuff). I will probably upgrade what ever engine it is with forged rods and pistons and some other strength upgrades.

Not trying to be rude here, I'm guessing your currently not old enough to drive yet? 

If this is the case, I'd stick with just watching stuff on youtube. If you find the right channels you can actually learn quite a bit there. 

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On 05/06/2025 at 6:48 PM, Murray_Calavera said:

Not trying to be rude here, I'm guessing your currently not old enough to drive yet? 

 

How could you tell??/??/???/? Yeah I got no idea what I'm talking about haha. I'll be on P's soon.

Quote

If this is the case, I'd stick with just watching stuff on youtube. If you find the right channels you can actually learn quite a bit there.

Yeah I figured that would be the case. Just wanna start learning to see how stupid of an idea it is. In general, I want to know so I can mod in future. It's interesting to know.

Thanks!

@RA708

All good mate. 

Once you get your first car and can get hands on, that's when you'll really start to learn. 

There are a million channels worth watching on youtube, but I'd like to make a recommendation. Check out the project binky series. Just a little bit of modding happening there, I think you'll find it interesting :)

 https://www.youtube.com/@BadObsessionMotorsport

  • Thanks 1

Save the youtube time, I can explain in a couple of sentences:

 

Internal Combustion Engines run on smoke which is factory installed. If at any time the smoke escapes (generally via the exhaust), the engine will stop running.

  • Haha 2
1 hour ago, Duncan said:

Internal Combustion Engines run on smoke which is factory installed. If at any time the smoke escapes (generally via the exhaust), the engine will stop running.

That's not completely truthful now is it? Any flex fuelled factory cars also had the option to run on steam.

  • Haha 1
2 hours ago, Duncan said:

Save the youtube time, I can explain in a couple of sentences:

 

Internal Combustion Engines run on smoke which is factory installed. If at any time the smoke escapes (generally via the exhaust), the engine will stop running.

And these modern "environmentally friendly" EV vehicles also run on the same smoke! When the engine, wiring, or batteries let it escape it also stops running!

  • Haha 1
On 07/06/2025 at 9:13 AM, Duncan said:

Internal Combustion Engines run on smoke which is factory installed. If at any time the smoke escapes (generally via the exhaust), the engine will stop running.

Oh ok that makes so much sense. Thanks for clearing it up!

On 06/06/2025 at 9:00 PM, GTSBoy said:

That's not completely truthful now is it? Any flex fuelled factory cars also had the option to run on steam.

And here I am purposely injecting water into my engine for the steams haha

  • Haha 1
On 05/06/2025 at 1:40 AM, RA708 said:

I have a terrible idea to twin charge a BNR34. Or an r35. So compression ratios and how they work as well as what certain measurements do for an engine (bore that sorta stuff). I will probably upgrade what ever engine it is with forged rods and pistons and some other strength upgrades.

Do a degree in mechanical engineering specializing in combustion systems and materials. Learn how to actually wrench on things that don't require 70k+ USD buy-in while you're at it. You also want to learn to weld and machine. If you still want to do this then you'll nominally have the knowledge to actually do what you're thinking of doing. Whether you still want to do any of that once you've actually gone through that process is anybody's guess.

Personally I cannot imagine anything more frustrating than trying to package a supercharger under the hood of any of these cars when the turbos are already fighting for every last inch.

  • Like 1
12 hours ago, joshuaho96 said:

Do a degree in mechanical engineering specializing in combustion systems and materials. Learn how to actually wrench on things that don't require 70k+ USD buy-in while you're at it. You also want to learn to weld and machine. If you still want to do this then you'll nominally have the knowledge to actually do what you're thinking of doing. Whether you still want to do any of that once you've actually gone through that process is anybody's guess.

Personally I cannot imagine anything more frustrating than trying to package a supercharger under the hood of any of these cars when the turbos are already fighting for every last inch.

Package SC on exhaust side.
Remote mount turbo.

Still a fair bit of room when you get creative on the inlet side of the motor too. Especially if you can get really creative with the welding, and effectively build it into the bottom of the inlet manifold. Would definitely take some design work, and some trial and error, to make sure flow works well still!

Might be easier to just start with the Nissan March though... All the work is already done for you... :P

Edited by MBS206
  • Like 1

Blower needs to go low on the exhaust side, displacing the AC and PS, which you have to decide whether you want to keep and how and where to relocate if you do. Electric option for PS is, at least, helpful. Sadly, there is no workable 12V electric AC of any value.

Whilst the blower is the last compression step before the throttle, and so it might seem a good idea to have it near the inlet manifold (as mentioned above), you probably want it to go through an intercooler first, so, having it on the opposite side of the car facilitates that air flow path. The turbo discharges into the blower, so proximity of the turbo's compressor outlet to the blower's inlet is nice. But then you might want to intercool that too, before boosting it again....which would probably be a ball ache. Routing pipes out to the front and back could be a bit shit. If there was room for (at least) a small (but preferably larger) water to air core on that side, then that would probably be the best approach.

I guess a reasonable alternative would be to locate the blower where the alternator is (more or less, associated with the inlet manifold, per Matt's thought), and somehow incorporate a water to air core into the manifold, sort of like they do for modern blown V8s. The big difference here though is that those V8s have only the one throttle (upstream the blower) and only the one compression step (the blower) and no need for too much in the way of bypass/blowoff valves. Whereas in a twin charged 6, you do need to think about one or two bypass valves associated with the 2 compressors and you would prefer to have the intercooling done before the air has to pass through the throttle. You'd like the throttle to work approx the same no matter what the compression is doing. But if it is located in hot air stream before a cooler, then sometimes the air will be real hot, sometimes it will be quite cool, and the throttle mapping/response will be quite different between those two cases. The throttle, if sized for hot air, would be too large for cold conditions.

It's all a ball ache.

  • Like 1
2 hours ago, GTSBoy said:

Blower needs to go low on the exhaust side, displacing the AC and PS, which you have to decide whether you want to keep and how and where to relocate if you do. Electric option for PS is, at least, helpful. Sadly, there is no workable 12V electric AC of any value.

Whilst the blower is the last compression step before the throttle, and so it might seem a good idea to have it near the inlet manifold (as mentioned above), you probably want it to go through an intercooler first, so, having it on the opposite side of the car facilitates that air flow path. The turbo discharges into the blower, so proximity of the turbo's compressor outlet to the blower's inlet is nice. But then you might want to intercool that too, before boosting it again....which would probably be a ball ache. Routing pipes out to the front and back could be a bit shit. If there was room for (at least) a small (but preferably larger) water to air core on that side, then that would probably be the best approach.

I guess a reasonable alternative would be to locate the blower where the alternator is (more or less, associated with the inlet manifold, per Matt's thought), and somehow incorporate a water to air core into the manifold, sort of like they do for modern blown V8s. The big difference here though is that those V8s have only the one throttle (upstream the blower) and only the one compression step (the blower) and no need for too much in the way of bypass/blowoff valves. Whereas in a twin charged 6, you do need to think about one or two bypass valves associated with the 2 compressors and you would prefer to have the intercooling done before the air has to pass through the throttle. You'd like the throttle to work approx the same no matter what the compression is doing. But if it is located in hot air stream before a cooler, then sometimes the air will be real hot, sometimes it will be quite cool, and the throttle mapping/response will be quite different between those two cases. The throttle, if sized for hot air, would be too large for cold conditions.

It's all a ball ache.

Just run it on methanol, and add a touch of WMI. :P

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