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Yep, and catching detonation before it gets out of control.
LMP1 Homologation build.. maybe Super GT
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Funny enough, I wanna try and run a pressure sensor in each cylinder somehow so I could technically do a running compression test per cylinder and get more accurate data.
Do you know if that's been done before???I know you won't let me down, this thread has been quite interesting the whole ride in so far.
There are cylinder pressure sensors, but I really don't know how you would implement them into an existing engine design. If I recall, it basically threads into the head like a second spark plug or direct injection. Neat idea, yes, for sure, but... how you'd implement it? I'm not real sure. Not even sure where I came across the idea, to be honest with you.
There are cylinder pressure sensors, but I really don't know how you would implement them into an existing engine design. If I recall, it basically threads into the head like a second spark plug or direct injection. Neat idea, yes, for sure, but... how you'd implement it? I'm not real sure. Not even sure where I came across the idea, to be honest with you.
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Yeah, they've been doing testing like that for decades. Don't think it would be cost efficient or any idea how long they would last. Heywood mentions it in his book.
news.mit.edu
Emeritus: John Heywood
He literally wrote the book on the internal combustion engine — and says rumors of its death are greatly exaggerated.
news.mit.edu
Right but now that they have back pressure sensor setups using map sensors and coiled exhaust tubing to cool down maybe if I did a correlation of intake side pressure sensors per cylinder and create back pressure sensors per cylinder. If there is a formula for pressure differential drops on the combustion v intake / exhaust stuff maybe it can come out with a constant steady state pressure reading that changes only with boost and maybe the type of fuel used?????? Now that I think about it I feel like I'm over complicating it. 😅
I mean if I did back pressure per cylinder I could build a tuning strategy to kill the engine if the pressure gets below a certain threshold or above a certain threshold... And set a code for low compression based on cylinder(s) X.
I think back pressure sensors are a far more realistic concept in this case than cylinder pressure, IF you could get sensors that tolerate the heat levels to be put into each runner.
That said, I have always wanted to know just how high dynamic compression ends up being with boost. I know that boost signal is taken from intake manifold pressure, but I have a scientist's mind...
That said, I have always wanted to know just how high dynamic compression ends up being with boost. I know that boost signal is taken from intake manifold pressure, but I have a scientist's mind...
Right, I know you could put tiny hard lines and coil them to cool off exhaust heat for back pressure sensors just would be an engine bay full of spaghetti lines everywhere 🤣.
I'm trying to build at F1 level 🤣
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277 Posts
Horsepower and engine tuning is the easy part, save your money for spare transmissions and brakes. If you make 600 horse and it’s not battleship heavy the thing will be a handful on a road course and you could make 600 thru a stock intake and like any standalone.
For reference the trans am2 cars eat gforce GSRs pretty quickly , and that’s with a sealed GM 6.0 LS, making ~600 at the wheel.
Your egt sensors will tell you all about your remaining compression When one goes hot and then quickly cold , you either ran out of spark fuel or compression or even more simply when it starts smoking out the breather it’s time to tear it down.
For reference the trans am2 cars eat gforce GSRs pretty quickly , and that’s with a sealed GM 6.0 LS, making ~600 at the wheel.
Your egt sensors will tell you all about your remaining compression When one goes hot and then quickly cold , you either ran out of spark fuel or compression or even more simply when it starts smoking out the breather it’s time to tear it down.
I'd caution against such enthusiasm, it's a quick way to run out of budget...
Neil has a point though, what transmission are you running? If I had taken the budget I put into building my engine, which I may have mentioned was a complete waste of energy and money, and put that toward an HGT sequential? I'd be WAY better off. That and by the time I invest in a proper H-pattern, plus the two R154 setups I've gone through... I mean... I've already spent HGT money.
You definitely won't have to worry about breaking one at a mere 600hp though. Pretty sure they're rated at over 1100+ ft-lbs, and all the rpms you could ever throw at one with a JZ.
Was planning on running dct or sequential. Leaning toward sequential tbh. I'm not shooting for stupid high hp figures just stupid high effeciency for making power. Not only am I doing time attack but I want to do Hill climb and endurance so I understand the other aspects hence the custom brake ducting im trying to make and the redistribution of weight. As far as budget im well aware considering I'm building as I go down the rabbit hole 🤣. Not going to lie hopefully one of my investments pan through here in the next couple years then I will never have to worry about a budget then 😉.
DCT costs just as much as sequential, plus you get the added fun of having to figure out how to tune a transmission as well as your engine. Truthfully, on paper, they have a LOT of potential. In reality, at least for now, they are a long way to go before they are what I'd call ready for the mainstream. Give it another 5 or 10 years of development and DCT's will probably be really nicely sorted, known qualities.
The biggest advantage the BMW DCT has over the HGT (and any of the other sequentials I have looked into) is the gearing spread. Having that seventh gear really allows you to have a fantastic first gear, as well as an actual highway gear in seventh. Would be perfect for autocross, road course, highway use... the gearing is just fantastic. Sequentials are more geared toward road course use, so you often have a reeeeeeeally long first gear, and a super aggressive sixth gear. Not great for autocross or highway use as a result.
However... a sequential is nice and light. If I recall correctly the HGT six speed is only like 80, 85 lbs... and it's a LOT simpler to integrate. If I had the money I'd be all over one myself.
The biggest advantage the BMW DCT has over the HGT (and any of the other sequentials I have looked into) is the gearing spread. Having that seventh gear really allows you to have a fantastic first gear, as well as an actual highway gear in seventh. Would be perfect for autocross, road course, highway use... the gearing is just fantastic. Sequentials are more geared toward road course use, so you often have a reeeeeeeally long first gear, and a super aggressive sixth gear. Not great for autocross or highway use as a result.
However... a sequential is nice and light. If I recall correctly the HGT six speed is only like 80, 85 lbs... and it's a LOT simpler to integrate. If I had the money I'd be all over one myself.
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Man the g force gsr 4 speed and a quick change is a sick setup tho, simple and easy to rebuild both
You know what's more sick though? Not having to rebuild transmissions that can't handle 600 ft-lbs.
Plus a 4-speed probably would be less than ideal for a Supra unless you really don't care about top speed at all. Not as much gear spread, or, if there is, you risk dropping out of the powerband of a JZ...
Plus a 4-speed probably would be less than ideal for a Supra unless you really don't care about top speed at all. Not as much gear spread, or, if there is, you risk dropping out of the powerband of a JZ...
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The sequentials you are mentioning will need rebuilt all the time like every purpose built racing box, the g forces are used behind much more powerful cars drifting as well, and they come out every weekend to get gone thru hombre. The dogs chip pieces off and if you dont catch it they explode
![Light Motor vehicle Circuit component Automotive tire Automotive design]()
I'd look into HGT, their maintenance requirements are acceptable enough that I considered putting it in my car (still would if I had an extra $16k laying around), and I really rather dislike doing transmission jobs...
Makes me wonder if there are some material issues in the G-Force setups. I don't have experience with them myself, but I never gathered that gears should ever be chipping away. That tells me that they're not up to the task they're being asked to do, or in the heavy equipment world, operator error...
Makes me wonder if there are some material issues in the G-Force setups. I don't have experience with them myself, but I never gathered that gears should ever be chipping away. That tells me that they're not up to the task they're being asked to do, or in the heavy equipment world, operator error...
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Are they that expensive now? I recall the HGT's being about 2k per gear. Planned to slap one onto a K20 swap in a Miata in the future (distance unknown).
That's why I want to go the BMW DCT and get my speed set through gearing and not power. My supra is being built for autocross/ time attack/ endurance blah blah blah lol. But yes even though the DCT are heavy bastards I think its worth the weight penalty and reliability. And since I'm planning on going 1.5way LSD rear end my biggest thing is constant abuse reliability.
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