it's close enough though

there's still some power lost in the driveshaft, differencial, and rear axels - it takes energy/power to turn those things. They don't turn on their own

 

Not close enough actually. There are significant drivetrain loss from the flywheel to the rear-axel.

For all intent and purpose, 'flywheel' ratings are essentially 'crank' ratings (very close) and 'rear axle' (or hub) figures are reasonably close to 'rear-wheel' figures (addition of wheel/tire). Now, I wouldn't think you'd assume factory 'crank' rating to be close enough with 'rear-wheel' ratings from a DynoJet, would you?


That is exactly what I have been preaching all this time. 'Drivetrain' is a generic term that encompasses all that sit in between the (engine) flywheel and the ground. For visualization (only major components considered):

Flywheel -> transmission -> propellor shaft -> differential -> drive shaft -> wheel hub (or rear-axle as I call it) -> wheel -> tire -> ground.

All of the above accounts for some mechanical and thermal losses. In the case of the DynaPack, it stops at the 'wheel hub'. For a DynoJet, the involvement reaches all the way to the 'tire'.

 

yeah, so JWT removed his wheels for his dyno. Doesn't his dyno attach to the hubs where the wheels attach to?

so the 400 hp figure is closer to the wheels than the flywheel then
yeah I agree - maybe we got mixed up with each other?

But still, we're talking 400 hp somewhat close to the wheels AT 8.5 psi

stock boost is at 6.8 psi, not 8.5

So why is JWT bragging about the 8.5psi 400hp when it clearly will be less than 400hp?

my point was that this kit looks to be roughly equal to the APS kit on stock boost levels

however the APS kit has a good track record, is out now, there's more experience with it, and it's capable of 800 hp, not 500 that the JWT is

 

One of the problems with that review imho is the boost pressure was not tested and documented for each turbo system tested, seems to me that running dyno tests without testing boost pressure is a real shame and makes it difficult for anyone to make a valid comparison between turbo system products.

I don't mean to be critical of the magazine or it's staff as any product review is worthwhile and I can only imagine how difficult a task this would be to organise so many test cars at one time.

Peter

 

That's interesting to know. We are all still waiting for the article to be sent out. Sounds like you were not too happy w. the results?

Were you present at the dyno facility? Why was boost not logged?

 

I don't think there is a good way to do a turbo shootout. Even if you bolted all the kits to the same car, weather could change, etc. I hope it concentrates more on features rather then how much hp it does on a stock motor. Kind of an arbitrary number to me since all the turbo kits on the market now will put out more HP than the stock motor can handle.

All the kits have their good and bad points (though the ratio may be different ). Horsepower on the stock motor doesn't really matter all that much, horsepower capability is a better number IMO...

 

I don't know anything about the dyno results, so I'm in the same boat as you guys.

No I was not present at any of the dyno testing though I have spoken with a guy who was present though he would not reveal any data pertaining to the dyno testing.


Lord knows. I can't understand why the boost pressure was not checked given that the cars were dyno tested and it would have only taken another minute or so to check boost pressure.

Peter

 

This is interesting. The JWT tech info significantly contradicts the JWT dyno results in the turbo shoot out. Mia should be able to comment on the turbo shoot out pretty soon. I’m starting to think some of the players at this “competition” were on roids, basically the playing field was not equal. Hmmm, Dr Evil style!!!

 

From what I've read, I'll stick with the APS TT and it's more awsome power, which I know of Z's (friends) running on their stock engines and not having any problems what so ever. Check out the "Street Racing in this Forum" That's one place you can check the "racing and the types of power and info of all kind" by the actual driver's who are happy to give you any info on the product their running. Check it out.

 

bump - anyone get any new info on this or the JWT TT kit?

 

Sport Z mag had the JWT for the comparison. Similar numbers to the APS and many accolades.

 

A friend of mine who owns a tuning shop knows Jim and Clark personally, I'll see what I can find out for everyone.

 

Any new information on JWT?

 

I just called them again and they said if the CARB cert doesn't come back soon, that they will release the kit as a tuner kit without the CARB approval. I wish they would do that now.

 

Call them back and see what the price would be without the carb certificate?