HiWire

Hey gang,

Does the North American 1993-1995 FD3S have the same turbo (Hitachi HT12) as the 1999-2002 model in Japan?

This article mentions a new design: http://www.rx7.org/Robinette/sae_article.htm

I'd like to build a sequential turbo setup matching the Spirit A specs - how much work is involved to update a '93 model, engine-wise?

Cheers,
HiWire

DaleClark

iTrader: (55)

Search, my friend.

They're commonly called the "99 Spec" turbos or the "280hp" turbos. They were only on the 99+ 280hp FD's. Some of the 99+ cars also had the "regular" turbos.

You simply get the whole set of twins and bolt them on. That's it. Nothing exciting there.

Used they go for around $800-1200, new around $2000-3000.

They mainly improve spoolup and response.

If you had a bone-stock FD and ran these at 10psi I doubt you'd need to change anything else with the system. But, like anything else, go up in boost and you'll need a PowerFC.

Dale

Dale

HiWire

Thanks, Dale.

I found Hitachi HT12-4's listed in some online catalogs but there isn't much detail about the differences in the series. I wasn't sure if the ECU would need reprogramming, fuel injectors, etc. I'll do more searching on these forums instead of Google.

I'd like to use the 280hp turbo to support mild future upgrades (mostly cooling/reliability) - I'm not looking for crazy 350+hp power.

MR_Rick

iTrader: (7)

IMO spending $2k-3k on a set of 99 spec OEM turbos for minimal gain is a waste of money. If you don't have a downpipe get one and save you some $. You will benefit from it more than than just installing a set of 99 spec turbo. Having the downpipe will give you quicker spool up and lower temps under then hood.

gracer7-rx7

iTrader: (16)

http://rx7.com/store/rx7/fdturbo.html

I have these on my car. Search and read the fAQ for many past discussions on these.

HiWire

Thanks for the link.

I've been doing a lot of research on buying an RX-7 for the last few years, but I'm only getting started on the engine details. At first, I was fixated on getting a '95 model, but they are nearly impossible to find in stock form at a reasonable price. I also looked at getting a JDM RHD model, since we are allowed to import 15-year-old cars in Canada. However, I decided that it would make more sense to stick with LHD.

So I've decided to take a different approach - get a '93 stripper/beater and build it up. It might be a bit painful since I don't have any skillz, but at least there are several good rotary shops in the Toronto area.

*RX007*

iTrader: (4)

Better have deep pockets I got my 99 specs because my stockers were toast and the they where half the price mazda wanted for the HT12's

West87

iTrader: (3)

Why not upgrade the stock ones to the BNR Stage 3 turbos?

KKMpunkrock2011

iTrader: (5)

I haz these for sale, PM what you wanna spend, 4k miles on them and Ari at Rotary Performance has them right now making sure they're good to go for whoever buys them. They'll be RP approved!

HiWire

I didn't know the BNR Stage 3 turbo existed - the price is comparable to the 99 spec HT12, but I don't plan to increase boost. Are they drop-in like the Efinis?

KKMpunkrock2011

iTrader: (5)

drop in is a matter of opinion, the twins are a pain to remove/replace with the motor in the car. You will get more power with the BNR's than with the ht12s, but the biggest advantage of them IMO is the ability to run more than 15 lbs of boost.

Mahjik

iTrader: (1)

They require modification of the Y-pipe which can be done by Bryan at the time he does the conversion on the turbos. Other than that, they bolt up like the stock twins.

TrboSpdAnt

iTrader: (5)

I actually have a pair of these laying around. Need rebuilding, but a local pick-up and a quick trip down to Charlie Brown at 'Evergreen' is STILL as butt-load cheaper than the almost 2600 the site's asking for.

Speaking of rebuilding them: How do they feel on your FD, vs. the stockers?

HiWire

Thanks for the info, guys.

I just took a quick at the FAQ sticky – learning about the FD3S seems to be a vocation.

I've read Mike Ancas's RX-7 Performance Handbook and Brian Long's RX-7: Mazda's Rotary Engine Sportscar, with Mark Warner's Street Rotary on the way from Amazon. Just the tip of the iceberg...

KKMpunkrock2011

iTrader: (5)

Heard from Ari yesterday, they're in good shape, all play is within spec and he should be shipping them back to me on Friday, of course it would make my life a lot easier if you just wanted me to ship them straight to you if you want them. 99 spec twins, 4k miles, I'm going single.

moconnor

iTrader: (14)

Has this ever been quantified?

Or is it based on marketing material?

Yes, I know they have abraidable seals - but does that and a buck fifty get you a cup of coffee?

KKMpunkrock2011

iTrader: (5)

I know here a buck fifty gets you a grande at some of the better coffee shops

moconnor

iTrader: (14)

A buck fifty will only get you a (small) coffee at a work cafeteria here!

adam c

iTrader: (2)

Someone please correct me if this is wrong:

As I recall, the only differences between our engines, and the 280 hp 1999 engines were the upgraded turbos and y pipe. Mazda claimed that the y pipe added 10 hp. That leaves another 15 by adding the turbos. If I am remembering correctly, this upgraded combo boosts about 11 psi instead of 10.

moconnor

iTrader: (14)

An additional 1psi of boost is going to give ~10-15hp on stock twins too.... Is there something that I missing here?

KKMpunkrock2011

iTrader: (5)

pretty sure the additional increase came from the improved factory ecu, not from increasing the boost pressure, I could be wrong.

Mahjik

iTrader: (1)

It's all of it together (as compared to the US 93-95's): No pre-cat, y-pipe, increased boost, upgraded ECU, etc.. It's definitely not the turbos alone (or any single component upgrade by itself).

HiWire

Was there any change to the intercooler or fuel system?

KKMpunkrock2011

iTrader: (5)

I don't believe so. As far as performance goes, the supsension, brakes, ecu, turbos, and y-pipe were the only thing changed that I know of.