[sdah]

hi

I'm building a k24 turbo 1000HP for rolling ( street racing ), not for drag, and I want to buy ( Quaife sequential transmission )

But I don't know which the best final drive is best for me (FD 4.357 ) or ( FD 4.750 ). I'm lost
because my car is too heavy.

some people told me you need 4.3 FD because of the long ratio, and in rolling, you don't need high torque

and some people told me to go with 4.7 FD because you need more torque to push your car weight

What do you think about that, guys? what you choose and why

and can Quaife sequential transmission Handle 1000HP ? or do I need billet housing


car weight: 3400 lb

transmission ratio
1- 2.417
2- 1.611
3- 1.263
4- 1.000
5- 0.852


I hope you can help me, and thank you so much.

 

[LotusElise]

Welcome to K20a.org @sdah.

I wouldn't built the 1000 hp based on a 99 mm stroke, the 86 mm stroke engine is much better for that: more durable, more controlable and more reliable.

But I don't know which the best final drive is best for me (FD 4.357 ) or ( FD 4.750 ). I'm lost because my car is too heavy.

I miss the information if this is about a FWD, AWD or RWD. The first and the last don't make any sense for street use, as the torque gradient is too high for one axis and the torque itself leads to endless slip. My friend an me building a 1200 hp drag race car, which is a Audi Quattro B3 chassis (around 1000 kg), this car has slipping tires on 4 wheels on glued tracks, on not glued tracks you see slipping tires still up to 180 km/h. To answer your question, for me 1000 hp are too much for the street, even the best AWD system, which is the Quattro, challenges tires, driver and material every time.

Quaife sequential transmission Handle 1000HP

It's not the power what kills the gearbox, it is force by engine torque. Your engine likely will see 39 psi of boost and around 620 ftlb. We use DCT system with a modified 14 plates clutch and a very strong gear wheel set from the Audi Sport. If you compare those wheels to the Quaify one you would say no the Quaify won't stand it. You should know which of the Quaify's. E.g. the lightweight 35 kg QKE8J for Honda...naaaah, I have my doubt that these survive more then 1000 shift events on over 600 ftlb's. The 6spd we are using has over 90 kg, the gear wheels are almost double the width of the Quaify and is known to be capable of up to 1100 ftlb's.

It would really help to help you if you explain more details about your project and yourself. So far I see an idea, which likely exceeds more then one line of capability.

 

[sdah]

hi LotusElise

First of all, thank you so much, @LotusElise, for your help and for sharing your experience with me. It was helpful. I appreciate that
and sorry I don't introduce myself, And I don't write enough information about my project.

I'm the kind of person who spends all his life reading and trying V8 LS engines And likes big sleeper cars.
So before five months, I decided to change my direction, and I wanted to build my new project with a four-cylinder engine.
I've been interested in Honda for a long time, and I like big sleeper cars with four-cylinder engines, so the best option for me is Honda. After reading about it, I got more excited, and I didn't want to change my mind.

however, I will use the car just for weekends and street rolling racing

after significant research, I choose Honda Shuttle 1997 ( AWD ) by swapping the k24 engine in it
And I will not reduce the car weight
It will be a sleeper ( whole weight )
that is my goal the car look stock, big and fast

engine:
I will buy a k24 (kt-1000 ) engine from 4piston this year because I like what they do
My target HP is 800-1000


Transmission:

( Option number one)

Here are my problems start.
In the beginning, I wanted to go with a dog box ( ppg gear set ) and ( billet housing + billet transfer case)
I saw some people break the transfer case and the housing because of high HP and torque.
I will buy from this website if I want the ( AWD) dog box.


( PPG DOGBOX Honda AWD TURBO Manual Transmission-GDDOGBOX-AWD )




( Option number two)

then, I do more research, and I found that (Quaife Sequential transmission ) ( QKE8J ) ( with AWD billet housing )
And after comparing between two transmissions , I found that they don't have a big difference in the price.
I thought Sequential transmissions are pretty expensive, and it's tough to get, especially for my old v8 projects. I always have a better option. That's why I don't think about Sequential transmission, but when I found that it is the same or close to the price as this dog box transmission(i mean Option number one )
I got more excited because one of my dreams is to buy a Sequential transmission.




But I'm a bit hesitant and confused at the same time Because I saw some people use this transmission with high horsepower and high torque. they're ok with that
they suggest to me to buy this transmission


But in another way, some people say the opposite like you @LotusElise. They said it couldn't handle, and some people broke it
So when I try to read more about this problem, I found that ( i hope you Correct me if I'm wrong )
it's not the problem with the transmission
the problem with the people who assembled this transmission
I mean the people who order separate parts and try to build the transmission of their own
they don't know how to do it well. That's why they make something loose or forget something, or don't know how to assemble it



at the end
I trust you @LotusElise, and I trust your advice, so please guide me to choose the best option for me
What I want is a transmission that can handle the power and last long
I wish I could have Sequential transmission

Thank you so much, and I'm sorry for taking a long time to respond or If I miss some Information <3

 

[Bense]

You're located in UK?

 

[sdah]

You're located in UK?

Yes I study in the UK at the moment

 

[LotusElise]

Honda Shuttle 1997 ( AWD ) by swapping the k24 engine in it

Thanks for the chassis details. The Shuttle AWD is used for highly powered drag cars and should stand your application. The question is how you are going to supply torque to the front and split it into different shaft speeds.

I will buy a k24 (kt-1000 ) engine from 4piston this year because I like what they do

Didn't I read you want to built an 1000 hp engine? No matter who built it, all suffer the same rod-stroke-ratio and therefore the same rod angle caused side wall forces. Our 1200 hp engine has also a big stroke - VAG I4-engines suffer on their small bore pitch of 88 mm - but uses a huge block height to increase the RS-ratio up to 1.65. A 2-Liter-I4 engine building for high performance out of an VAG basis is very challenging, while it is so easy on a Honda K-series. But the Honda 99 mm stroke has an 1.54 RS-ratio, scrapping and wearing the liner hone much more then an 1.65 RS-ratio engine. If engine speed is increased or or and cylinder pressure, you increase this issue too. 4P applicate this for street, road race, time attack and drag in one setup, which are totally different 3 applications. Maybe it comes with application specific maintenance schedules?! I still don't like this idea, each application should have specific piston-liner wall and ring gap clearances as heat flux duration and heat cycle variances are different enough, beside the higher seizure capability of the low rod stroke ratio.

( QKE8J ) ( with AWD billet housing )

Please speak with them, they are responsible of knowing where are the limits of the product.

Beside that, of course reports about their capability are different as the applications and shift habits are different. The biggest teeth crasher moments are the moments when the clutch begin to grab and starts transferring torque while engine speed of the engine is different to that of the tire. On glued tracks this leads to massive torsional shaft oscillations and factorizes the teeth load which is already there. Just giving you an example. At MTU (oldest industrial series engine producing company of the world, well known for the Leopard 2 tank engine and other stuff) we had issues with broken damper clutches. I made an investigation in why those rubber clutches get destroyed and plugged a torque sensing system in between crank and clutch as well as clutch and generator. After seeing the start torque oscillation it was clear, peak torque of start was almost double of the WOT torque, just because it oscillated in resonance as generator has 0 rpm and the crank forced that heavy generator inertia to rotate. The result are torsional resonance which destroyed the rubber. Adding a torsional balancer solved that issue. The clutch in process has similar mechanism, shaft speeds are different, inertia masses of engine and drivetrain have different speeds which means transient effects have to overcome. Race applications are not well known to be able to adapt this in kind way, time is money here, so the result is fully depending on shift behavior (flat shift, dog shift, slip capability of the system (clutch, tires, ...), duration to adapt speed difference, and so on...) and some other parameters.

The Shuttle AWD system has a visco coupler system, which means speed differences control the torque distribution, that could soften a bit the transient behavior. Not sure about that, just my assumption.

 

[JMURACN]

your FD "usually" is used to determine your top speed and not much more... especially in this environment.

a 4.3 will give you a potentially higher top speed but you will be slower to get there... a 4.7 will have a lower top speed but get you there faster.... this assumes redline is the same for both FYI.

 

[AngryScotsman]

couple of thoughts:
1. The issue with the car have traction on a "glued" drag strip isn't relevant. It sounds like the OP is a street racer (LOL), which means that launches where there's a lot of grip is never an issue.

2. Street racing (LOL)

3. 1000hp builds, regardless of engine/setup, is going to be somewhat unreliable. Sheepy built twin-turbo Lambos/Audis aren't known for their longevity. You MUST accept that things will break. It's not an "if", but a "when". And things always break at the weakest link. Do you want the weakest link the transmission, axles, clutch, etc. Build accordingly.

4. One of the issues with a shorter FD is that you shift more. More shifts means more time not accelerating. This is more of a problem in a h-pattern box, regardless of dog-engagement or synchro. The longer FD will let you stay in the power band longer. Since you're street racer (LOL), I imagine staying in the powerband longer until the other street racer (LOL) backs off is the key to winning.

5. I went with the longer FD on my sequential, but I'm also doing time attack/autocross... so having a wider usable powerband is more advantageous than quicker acceleration. Just tune and size the turbo appropriate for a better power-delivery.

 

[Lotus]

or buy a Tesla Model S Plaid and be done with it. Even comes with a warranty. ;-)

 

[LotusElise]

or buy a Tesla Model S Plaid and be done with it. Even comes with a warranty. ;-)

Just recently I made a simulation of a 1200 hp 1/4 mile engine in an Quattro B3 Chassis validated it with real world data and electrified the chassis with 4 wheel drive e-motors. Aim was to achieve the same quarter mile time. All assumptions were made on real weights, inertia and specific weight to power ratios. Was quite interesting and gave me a better understanding of the Rimac car. But make it clear, the electrified Quattro demanded more electrical power then the ICE one, just because of the 2-gear system. Battery capacity was calculated on 6 runs energy demand = 112 kg.

 

[MadK]

hi

I'm building a k24 turbo 1000HP for rolling ( street racing ), not for drag, and I want to buy ( Quaife sequential transmission )

But I don't know which the best final drive is best for me (FD 4.357 ) or ( FD 4.750 ). I'm lost
because my car is too heavy.

some people told me you need 4.3 FD because of the long ratio, and in rolling, you don't need high torque

and some people told me to go with 4.7 FD because you need more torque to push your car weight

What do you think about that, guys? what you choose and why

and can Quaife sequential transmission Handle 1000HP ? or do I need billet housing


car weight: 3400 lb

transmission ratio
1- 2.417
2- 1.611
3- 1.263
4- 1.000
5- 0.852


I hope you can help me, and thank you so much.

For a 5 sp I’d go 4.3 and with 6 sp 4.7

 

[Thefat shop]

hi

I'm building a k24 turbo 1000HP for rolling ( street racing ), not for drag, and I want to buy ( Quaife sequential transmission )

But I don't know which the best final drive is best for me (FD 4.357 ) or ( FD 4.750 ). I'm lost
because my car is too heavy.

some people told me you need 4.3 FD because of the long ratio, and in rolling, you don't need high torque

and some people told me to go with 4.7 FD because you need more torque to push your car weight

What do you think about that, guys? what you choose and why

and can Quaife sequential transmission Handle 1000HP ? or do I need billet housing


car weight: 3400 lb

transmission ratio
1- 2.417
2- 1.611
3- 1.263
4- 1.000
5- 0.852


I hope you can help me, and thank you so much.

4.357.....long ratio. Not slip.

 

[Bense]

Your vehicles weight and your power goals look very similar to the kinds of builds that we have near where I live.

I would suggest playing with this particular calculator and get an idea of how fast it would be in the quarter mile.

1/4 Mile ET Calculator

1/4 & 1/8 Mile Elapsed Time Calculator

robrobinette.com

 

[LotusElise]

4.357.....long ratio. Not slip.

With the 4.357:1 FD and a first gear of 2.417:1 the car may have, depending on tire size, around 107 km/[email protected] rpm. That chassis getting moved will be difficult as the K24 in NA load, with an torque capable clutch will be not easy to get into rolling, while top speed is only 268 km/[email protected] rpm. Bigger tires then those 1.95 m circumference tires will increase both of course, the difficulties to get rolling and the top speed. Sure slip will be lower, but the 4.750:1 FD won't solve the get rolling issue significantly, still runs almost 100 km/[email protected] rpm and 12 km/[email protected] rpm on a AWD. That clutch need to have a good controllable sweet spot. We don't have to forget, this is an AWD, run by an tiny 88x99 I4 engine, which has not much torque around idle speed. The turbo helps that engine at much higher speed to get into reasonable torque, below 3500 rpm it is just an restriction for alternation of load and combustion efficiency.

For me the hole setup expands many comfort zones for the driver. First gear is a mismatch for both FD gear ratios, and black stripes on street are at any time possible on a 1500 kg AWD, when torque gradient arouse from sleeping. The idea sounds impressing: family AWD car with 1000 hp, a real sleeper concept. But it comes with a lot of expanded compromises. For me it's a mismatch in many requirements, but this are just my personal two cents.

Anyway, I am here for help. It's a visco coupled AWD system, that means enough time to slip before the other axis supplies enough torque in addition, because on a 1000 hp the torque rises from around 180 ftlb in between 500 rpm to 600 ftlb in WOT. Town driving at 50 km/h is in 1st gear at 4500 or 4800 rpm, which is on a Y2M3 tranny done normally at 2nd [email protected] rpm. The stock shuttle gear ratios might be even shorter set then this, because of the 1590 kg chassis weight and the tiny NA engine.

I would generally think about a customized gear ratios and less power for a better driveability, so to say low end torque capability driven by a better fitting turbo. Otherwise you need an e-engine to support the city driving task, solutions are available regarding this. This is no 1000 hp-V8 with 6 Liter NA-displacement, it's a tiny but highend supported engine which run on city traffic most of the time below turbo support and once demanded the introduction lines into the street of the turbo are granted.

 

[Bense]

You are wasting your time trying to use that K transmission. I'd suggest that you take a step back and think about what you're doing from a broader, birds eye perspective and consider other Honda platforms that might be available for you to pull parts from.

I am currently working on a customers car,
2013 Acura TL SH-AWD 6MT - J37A4

I'm changing out some gearing on it.