nopiston_racer

iTrader: (2)

Im getting ready to turbo my 12a...well actually im turboing a new 12a streetported engine with 0 miles on it....here are what im looking at installing:

Garret t04b turbo
Tial 38mm wastegate
Holley 575cfm or 600cfm carb
Blow-thru turbo setup
MSD ignition
Nology spark wires
FMIC...looking at PWR
ACT clutch
Lighten'd flywheel

If anyone has any advice im open for it...and im looking at purchasing a lot of this in about 2-3 months...so the more advice the better....thx guys...parker

QuagmireMan

i am looking to do the same, except draw through

SS124A

how aboot some magnacores or ultras???

Alak

iTrader: (9)

Dont forget a better transmission. If your using an FB one, it likely will hold a few passes down the strip before problems arise.

Gregs

the stock fb tranny is supposidly good to 300hp

tuned perfectly i could see your setup getting 250-275 hp @9-10 psi

Rotofire

I'm doing the same thing. (12aT SP)

Here's what i'm using:

Stock s4 turbo and mani.
Stock TII front mount IC
Custom exhaust
Weber 45dcoe (blowthrough)
BOV has yet to be decided.




How do you plan on running your oil line for your turbo?

mikey D

the 12a tranny is just fine.
250whp and still shifting fine.

mwatson184

Are you modifying the carb yourself or sending it somewhere to be modded?

Marques

nopiston_racer

iTrader: (2)

How do you plan on running your oil line for your turbo?

Im thinking of running it from the oil cooler straight into the turbo and back to the engine.....or im going to put a T on the oil return line from the cooler to the turbo...im goin to ask a friend with a turbo 12a how he did it

Are you modifying the carb yourself or sending it somewhere to be modded?

I think im goin to have someone else mod it....thinking of having the guy im buying the engine from mod it....or maybe someone near jacksonville, NC

hondaslaya

iTrader: (3)

what ever you do dont cut the oil cooler lines with out back up lines( I know this from experience). You should get the carb from racing beat they custom mod holly carbs for the manifold for a perfect fit.

shm21284

Where the hell did you get these numbers? I can see 250@ 10psi on a 13b, which has more displacement. He could get 250-275 at around 15psi on this turbo, properly tuned, with 3 inch exhaust, SP, front mount intercooler, etc.

1stgen4life

iTrader: (1)

Stock TII intercoolers are top mount. Are you just going to put it upfront? Sorry for the threadjack, but I was just curious.

fitzwarryne

The 12AT official power was 165hp JIS flywheel, which is about 140 bhp SAE as used in the USA. In comparison the 12A was rated at 130hp, equivalent to 100bhp SAE.

The 12AT went into production in 1982 for use in the HB Cosmo then the quickest Japanese production vehicle, and gave a top speed of 235kph [148mph] and a 1/4 mile time of 15.2 seconds.

When the sales of the RX-7 slumped with the introduction of competing more powerful sports cars, the 12AT was offered as an option in the 1985 model. It certainly improved the performance which officially was 220kph and 13.4 seconds, but still not as quick as the Cosmo. The 12AT was marginally more powerful than the 13B introduced into the USA but had 15% more torque.

About 420 RX-7s were sold with the 12AT option, a disappointment to Mazda but caused by photographs in mid 1985 of the Gen 2 preproduction cars. In fact news of the P747 project was common knowledge in the automotive press in 1982 when the first focus groups met in the USA to establish the outline specificaztions and marketing target of the Gen 2 or series 4 as it was officially known.

The 12AT is an outstanding engine, the 12A with an added turbo is just a compromise with a large thirst!

mortenf

Here are some pics of the Cosmo, and its original engine, plus a pic of a friends 550 BHP "compromise"

kuhlrx7

did the 12at not come in a rx7 in 83 in japan? august or september, then have a few revisions to the engine/turbo/ecu for the 84+ model year at 172hp? 420 total manufactured units ?? some how I belive it was a bit higher than that. wasnt that 85 model year only jdm sold units and short model year because of the early intro of the 2nd gen. and wasnt there some 200+ 85 model year 12at rx7s sent to aust/nz and europe markets after the 2nd gen intro in japan?

is not the 4 door 12a turbo a luce/ 929 )? wasnt the cosmo model aka rx-5 and a 929 coupe?

mwatson184

I can boost prep the holley for you, if you are interested PM me.

Marques

FB II

stock port 12a with good compression..... 230rwhp or so... street port 270 or so; the limitation is the turbo.

fitzwarryne

kublxrx7:- The Japanese 1984 model RX-7 which went on sale in September 1983 had as an option the 12AT with the Hitachi 62mm turbo. The 1985 model had the smaller 57mm turbo which gave 5hp more, a total of 165hp JIS, but with better low end torque and reduced turbo lag- presumably because of greater rpm.

In the period Japanese manufacturers had gone turbo crazy and the Skyline became fashionable along with several other hot vehicles. Mazda is very relectant to give option information but 420 is the best estimate of 12AT powered RX-7s. This is why they are now a collectors item fetching fantastic prices.

The HB Cosmo had the 12AT as an option. The HB Luce was a heavy luxury vehicle and usually came with the 13B. However the HC model had the Series 4 13BT as an option along with an in built frig to keep your drinks cool!

The RX-7s only came with the manual transmission, the Cosmo and Luce usually automatics. In fact the 13B efi ,as in the GLSE, only came with an automatic.

The Cosmo/929 came in a range of body styles. I once had a 79 wagon which ten years latter received a13BT and made a great family hack for my kids to drive to college. I justified the switch as they needed to learn on a manual to get a full driving licence.

Whizbang

^^^walking encyclopedia^^^

fitzwarryne

Not walking,driving a great car- a s3 Rex! Often making a 12 hour trip I have time to think of their history and what still makes them great inspite of technological improvements. Tried a RX-8 but it just left me cold, could have been any modern car.

As a matter of fact I got one point wrong. No 12AT was exported as a race car.

After Alan Hansford did well at Bathurst in 1982 driving a 12A PP race RX-7, Mazda brought out a series of replicas. But the modification was body work only with a stock standard 12A. They only looked fast! About 3 were later fitted with 12AT engines from the Cosmo exported from Japan to Australia, and mistakenly thought of as original race cars.

REVHED

Hey Paul. Good to see you here again.

ssglopezvm

Heres what Im running...

236RWHP @ 10psi

*New 12A Motor/Mildly Street ported & polished
*1991 Transmission
*Racing Clutch & Pressure plate
*600 CFM Holley Carb
*Racing Beat intake manifold/polished
*T4E Garrett Turbo/ P-trim .60 Compressor, .69 Turbine
*Custom fabrication of Turbo manifold and 3" exhaust downpipe
*Turbonetics Boost controler, Carburetor cover and Wastegate
*TurboX Blow-off Valve
*Custom Intercooler w pipes
*Magnacore Wires
*GSL-SE 4.10 Gears
*MSD Igniters & Coils
*Bosch fuel pump regulated at 6-25psi
*Electric Twin Cooling Fan

fitzwarryne

Hi Revhed. Its great to be back. Spent recent year up on the Afghan- Chinese border and had to lay up the RX-7 until I got back. Usual problems due to lack of use, for example new KYB shocks leaked. Am about to start total engine and suspension rebuild before next trip. Drove interesting road China to Pakistan which reached 5500 metres as it wound round K2. Not rotary territory!

What are you driving now, my last memory was a 20B Cosmo?

regards Paul