just watching this short vid of the 300zx doing 186,5 mph wounder if this is in stock gearing ?

 

While great he is doing that speed, he is running 850whp. IMO it just shows how the box isn't built for top speed/have enough gears.

i found the z to be very stable at high speed and the box has tall gears so am not sure why you said not built for high speed ?

This is my friend Ray's car. Ray lives in Crete, Nebraska. Its eaten a number of drive shafts. I've driven it too - it's immense. Fortunately, it has a Quaife differential and it handles the power well. Quite a lot of turbo lag through regular driving as it's built purely as a drag car. You'd have thought it would have been terrifying to drive, but it's so well set up

 

Ray's aim is 200mph

i found the z to be very stable at high speed and the box has tall gears so am not sure why you said not built for high speed ?

As in cars with a similar power. Say a jaguar xj220 which has circa 500 (crank) will do 217mph.

And a modern Porsche 911 with 500hp will do 205. Get my point?

 

I'm not knowledgeable enough to tell you why but I would say part aerodynamics, part weight, part gear ratios.

Aerodynamics are not the issue. The gear ratios, rev limit and torque are. Ray's hit 197mph (clocked). It is set up as a drag car though, not a top speeder, although as the car evolves, his ideas and use change.

 

You should be able to achieve 200mph with a strong engine that can rev much higher, some more power and a different final drive.

......also bear in mind that this was only over the course of a mile. It goes much faster over a longer strip.

As in cars with a similar power. Say a jaguar xj220 which has circa 500 (crank) will do 217mph.

And a modern Porsche 911 with 500hp will do 205. Get my point?

 

I'm not knowledgeable enough to tell you why but I woulsay part aerodynamics, part weight, part gear ratios.

xj220 vs a 300zx come on lol..... even a stock 300zx has a mega top end

 

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Aerodynamics are not the issue. The gear ratios, rev limit and torque are. Ray's hit 197mph (clocked). It is set up as a drag car though, not a top speeder, although as the car evolves, his ideas and use change.

 

You should be able to achieve 200mph with a strong engine that can rev much higher, some more power and a different final drive.

 

will a stock car do 180 ?

Stock car will do around 175 with the limiter removed given enough distance. Over the course of a mile, it would probably pull 130/140

let be honest that pretty good going. so with more juice will it do more or is that the top of stock gearing

Increase the rev limit and up the power. It takes an exponential amount of power the higher top speed you require and it will take quite a lot more power to gain those higher top speeds than you'd think.

with the 2nd engine am building the goal is 650 to 700bhp i plan on doing a max top speed at some point so time will tell

As in cars with a similar power. Say a jaguar xj220 which has circa 500 (crank) will do 217mph.

And a modern Porsche 911 with 500hp will do 205. Get my point?

 

I'm not knowledgeable enough to tell you why but I would say part aerodynamics, part weight, part gear ratios.

 

Ali mate the stock car will do 170+mph at 280hp. It will take you a long time to get there but it will go there. Hopefully Nick will chime in but one or two of the guys have trapped 150+mph on top speed runs at TOTB etc, hopefully they can be more detailed. Even the mighty Veyron wouldn't be hitting it 250+mph top speed on a half mile strip they need that banked oval to set that speed.

http://www.roadandtrack.com/new-cars/car-comparison-tests/reviews/a20274/speed-kings-bugatti-veyron-164-1/

To give you a marker zebedee clocked 135mph on the flying kilometer at TOTB running 340bhp.

A Committee member passed me at about 140mph not so long ago. :whistling:

My Car pulled 172 on gps ..(private road) so 180 is achievable as mine was still climbing slowly when i had to let off:cool3:

when the cars done am going to find a safe off the public road to max it out i will make a vid

Maybe a convoy to the autobahn?

Maybe a convoy to the autobahn?

 

Be careful on German autobhan. Whilst there is no speed limit, German police are very hot on driving with due care and attention. You will get pulled over for doing high speeds in more urban and busier stretches or when the visibility isn't absolutely perfect.

 

Basically, it needs to be empty with no traffic on, dead straight road in good daylight driving conditions otherwise your ass will be theirs.

A Committee member passed me at about 140mph not so long ago. :whistling:

 

Not on the public roads I hope Gaz..... That would be just irresponsible - I mean which one of us would have done that....:lol:

With enough space and either a raised rev limit or adjusted final drive a Z will break 200mph. I hit 181 through the trap in 1.6 miles at pretty much 7000 rpm. While it was still pulling and with enough space I think it would probably have only just breached a genuine 190 before hitting the 7200 limiter.

 

While the shape of the Z is aerodynamic, there are other aero problems to take into consideration, such as air flow through and out of the back of the intercoolers being a biggy at those speeds. As is thermal management for all aspects of the engine (intake temps, fuel temps, air temp around the engine itself) which is what ultimately cause my engine failure when pushing the car so hard.

 

It's not as simple of just having more power and enough room in a car that wasn't designed to perform at those speeds

Get the right mods sorted (lots of them) and over 260mph is possible and done in a Z32. Remember this old gem;

The Japanese tuning shop JUN Auto entered the USA Bonneville Speed Trials in 1991 with the JUN-Blitz 300ZX in the E/BMS class.

JUN ran a record 260.876 mph becoming world champions and setting a record that still remains unbroken.

 

Videos of Blitz, TBO and JUN Auto preparing their 300ZX for Bonneville.

 

http://www.300zx.co.uk/forums/showthread.php?173754-Blitz-TBO-and-JUN-Auto-preparing-300ZX-for-Bonneville

Edited September 4, 20169 yr by AndrewG