I am considering buying a 1985 GSL for $2500. I've seen different carb set-ups on rotaryshack, racing beat, etc...

How much performance improvement is there from changing a carb, really? Rotaryshack claims "up to 60 h.p." on a lot of set-ups, but is that really feasible simply from a carb? Ideally, I would like to go with a rebuild, street port, and racing beat full exhaust system... I honestly don't know how easy/difficult a 13b swap would be, so how much power can you reasonably expect from a 12a without going the turbo route? The first RX-7 I saw that is really what got me into them was this guys 82 GSL with a 13b streetport and the Dellorto side draft... I found the side draft kit on eBay, and I want to know if there really is a benefit to getting it.

Sorry if this is rambling... My brain is on overload from my new job.

 

Search N00b!

Well just like any rotary you need a good exhaust first, then intake mods will make their fullest potential. Full RB exhaust and a good intake system on a good engine could yield 170-180 hp on a 12A.

 

I did search... That's why I'm asking.

That 170-180 hp... Does that include porting? Why is it that just a carb can give that kind of improvement? Is it that the stock carbs suck?

Oh yeah, is it easy to swap an N/A 13b in? Will it bolt right up?

BTW, Carl, how's your daughter doing?

 

Hey Kevin,

I have a Mikuni carb on a streetported 12a with a Racing beat head straight to the muffler. I love mine. My first car was a stock 83 and this is a HUGE difference. I don't know how much hp i am pushing or know my 1/4 miles times are, but it is quick and loud. I have heard around just under 200 hp can be hit. The advantage of the carb is that it is less computer stuff to deal with. Plus most people are more familariar with carbs anyways.

I hope this helps. I feel like I am rambiling too

Ryan

 

well I think that is with a streetport. Stock carbs are good with some mods. If i am correct Carl actually is the man to talk about moding your stock carb.

Also $2500 that seems pretty steep unless it is modded to hell. I paid $750 for my streetported baby.

 

It's not modded at all, and it's the cheapest in the area (within 300 miles) on autotrader.com.

 

http://cgi.ebay.com/ebaymotors/ws/eB...sPageName=WDVW

BTW, what do you all think of this?

 

Yeah I saw that on there the other day. It looks really nice. since it comes with the manifold i would think that it is worth it.

Where are you located? Are you dieing to get one now? I bet if you wait a bit you could find one that might be a little better price. Also my other rx7 (85 gsl) I got for $900. Completely stock but interior and exterior in really good condition. But I really had to search for that one and wait for my time.

 

where are you located? I know in most other states in the south or on the coasts, its easy to find a good running 1st gen for cheap, but here in MN, youd probably have to pay double. I havent been looking lately, but when I did a while back on carsoup and autotrader, the cheapest one was about 2500. The two I bought more recently were $200 and $100 but neither ran...

 

J/k, Ive never seen you here b4, just giving you ****.

No, thats stock porting. Yaw has some dyno sheets to back that up. And thats FWHP AFAIK. It's not just the carb. Its exhaust, a good intake system (from air cleaner to manifold interface), upgraded fuel pump (necessary with any performance intake) and reg. Also an MSD6A is a good idea too.

Doin better, shes finishing HS and will be going to CC over summer. Shes still a PITA teenager, but what can you do. Their all like that, its what Bill Cosby called "brain damaged"! She'll grow out of it, just not soon enough for me.

 

I'm glad she's home.

The reason you never see me here was because I had my heart set on another T2, or an FD, but then remembered how much fun my FB was... And all the things I always wanted to do to it, but never did...

So, you guys never did answer my question: Is a 13b swap easy, or a pain in the ***? I'm talking carbed 13b, not FI. If I had a 12a with a street port, the full RB exhaust, the Dellorto or Weber set up and the ignition system, what kind of power do you guesstimate I would have? What about the same type of set up with a 13b? Is it possible to go N/A and have 250 hp?

 

which 13B are you talking about? 2nd gen ones need a gsl-se front cover/brace and oil pan/pickup.

 

Any old 13b.

 

Alright, so there's a cheap GSL-SE near me. Would I be better off using something like a weber or Dellorto with it, or is the FI better? I want over 200 h.p.

 

Carburated is the way to go. Streetported 13B with carb and all the mods can reach over 200 ponies, flywheel that is.

 

WIth a SP it better make more than that. I recall seeing dyno sheets that showed a SP 12A making over 200 FWHP.

 

So, assuming I go with this SE, and want to run a Dellorto or Weber side draft, I guess I can eliminate the computer and will probably have to swap fuel pumps, right? IIRC, FI requires a lot higher fuel pressure than carbs.

 

Mallory makes a bypass-type fuel pressure regulator that drops high pressure down to low.

 

What about the computer? Can I get rid of it altogether?

 

yea, you'd need to swap over to a dizzy from a 12A and well pretty much run our ignition.

 

I hadn't thought of that. Is that difficult?

 

Let's go back to the beginning.

A GSL is a carby 12A producing new 100hp. With bolt on modifications including modified Nikki carb and a good header/exhaust you can get about 140-150hp;

Rebuild the motor and porting gives you about 180hp with a mild port and the modified carb. Its still a useful daily driver. If you get a bigger port, eg bridgeport,
and go for a bigger carb such as a Webber than around 220hp is possible if you dont mind high revs, noise and pollution. As the engine has been 'refreshed' during the rebuild it should be reliable.

Going to turbo charging is a different story. Rotary Shack saying up to 60hp is like a fire sale advertisement, even 1 hp is valid in the 'up to' claim. The reality is adding a small turbo generally gives you about an extra 35-40hp at around 7-8 psi boost. If you go anything larger than I would seriously think of a rebuild first- its a 20 year old engine with possibly worn seals. Adding a larger turbo and and a megaturbo then 300-400hp is possible but with a short engine life.

Changing to a 13B is roughly the same track with an extra 10%, but getting a late 13B turbo and spending big will get you 500+hp.

One option which is worth considering if you want a cheap engine change is buying an imported low mileage late version 13B engine, and going back to carby with a Webber such as a48 IDA. This cuts out the cost of a ecu and new fuel system.

It's a cheap and reliable way of getting 200hp in a daily driver.

The hp estimates are all at the flywheel.

 

Apologies part of my post got lost in the server.

Adding a large turbo and intercooler with upgraded fuel system can get you 300hp, but spending megabucks with everything including dowelling and a megaturbo will get you 400hp but a very short engine life.

For track only configurations, the sky is the limit subject to the bank manager's limitations. The 1000hp barrier is there to be broken!

 

no the dizzy should just drop right in and the ignition is pretty straight forward.

 

Wow, that was helpful!

All I'm looking for is a reliable 250 h.p. (at the flywheel) that won't be incredibly loud and that I can drive around most days when the weather is nice (in other words, no snow). So, I think to get to that number, I should start with a 13b and a streetport/rebuild. A full exhaust like the one from Racing Beat is common sense to take advantage of the street port. The next two things to be handled are ignition and carb/fuel, right? Am I missing anything?