Cihuuy

Guys... what's the difference btw the 1993 and 1999 OEM twin turbo? i want to know if there is a design differences like compressor wheel, shaft, wastage and etc etc...

i read some threads that some ppl have swap turbos... what are the benefit of the new ones? tanx in advance

salamander

Have a look at this site.....


http://www.sae.org/automag/global_viewpoints/01.htm

Cihuuy

Salamander: Tanx dude... very informative...

This is the improvement of the turbo (if some1 wants to take a look at it)

Hitachi has since come up with a new built-up construction of the compressor housing. A formed plastic inner sealing element is bolted onto the main housing, and then machined. The turbocharger is assembled, and run up to 100,000 rpm, abrading the inner surface of the plastic seal, obtaining the closest clearance between the compressor and housing. The new abradable turbocharger has an 80%-plus efficiency, whereas a typical instrument's efficiency is about 75%, according to a Mazda designer. This brings down the compressed air's temperature by 10°C, or about 10%, at the exit of the compressor. Air temperature is still in the region of 110°C (230°F), which is further cooled down by the air-to-air intercooler in the RX-7 installation.

The latest trend in high-performance turbo technology is a "diagonal flow" turbine. Mazda asked Hitachi to come up with several candidates of this design, hoping it would boost the engine's output. They did not quite match the rotating piston engine's unique characteristics. Back to the tube, as it were, to research basic flow dynamics. The fruit of the toil is the "ultra-high-flow" turbine, with its blade length extended and its shapeless acutely curved, enlarging gas passage and reducing flow resistance. Turbo response in the low speed zone has been greatly improved. The turbocharger adopts a smaller diameter turbine, 50 mm (1.9 in.) now versus the previous unit's 51 mm (2.0 in.), again reducing inertia mass. The new "ultra high-flow" turbine realizes about a 10% gain in efficiency, according to Mazda's turbo engineer. The twin ultra-high-flow turbochargers supply a maximum boost of 74.7 kPa (10.8 psi) at 6500 rpm to the previous high-flow instruments' 62.7 kPa (9.1 psi) at the same rpm.

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So my next question is... how much HP would i be seeing in swaping to a '99 twins? and what are the other necessary parts to make it work(ECU, injector)??

Sorry for the long post..

Joker

MORE

nless7

For the money u would spend on those 99. I would probably buy the upgraded stock turbo units for Jason at Rx7Store.

Cihuuy

Joker: MORE???

nless7: i dont think i would be able to get those parts from where i live whats the upgraded stock from rx7store?

was looking for a used '99 from japan... but i would like to know the benefits into doing that... more pros or cons? i hate lag so i still want my sequentials...

Mahjik

iTrader: (1)

Here is a thread about someone who installed the '99 spec turbos:

https://www.rx7club.com/forum/showth...threadid=94390

As for the BNR Upgraded turbos that the RX-7 Store sells, I think they are a MUCH better deal. You can order from the RX-7 Store, however since you are overseas you'll need to workout the payment part with Jason. Typically, I don't think he does credit cards since it's hard for him to verify overseas cards but usually you can fax some info to him and get your order rolling.

israel

iTrader: (3)

a couple more visuals





happy boosting,

israel