jamesdeanrx7

hey guys jsut saved enough for my 20b purchase. was curious before i have it street ported. is it possiable to get 400 to 450 without porting. Im going to use the stock turbos modified of course and the injectors but was curious on the factor of porting to do or not to do?


jd

Bitchn7

if you pull it apart, port it, if you don't, well you can't.

400HP should be easy without porting. they are 320+/_ standard with all the emmision **** that comes with them so 400 is a no brainer realy.

Bridgeported

400-450 is definitely possible with a 20B using stock internals. Especially with modified stock twins running in non-sequential. Pump those bad boys up to about 12-14 psi and you should be over 400.

jamesdeanrx7

Sweet but oen other question, Should i get my motor rebuilt with stronger pins and just a basic rebuild period to be safe or not. Well i think if I do that then well I mine as well just have it street ported if I have to do that right?

Evil Aviator

That's what I decided for mine. I'm going to try running mine first with the stock internals. If it runs well, then I will just run it that way until it needs a rebuild, at which point I will add the street porting. If the engine doesn't run well as-is (bad compression, coolant leaks, etc) then I will rebuild it and add the street porting. I don't see much reason to take apart a perfectly good engine just for street porting.

I'm not sure what the stock turbos are capable of when modified, but see here for a dyno sheet of a stock 20B block making 457 hp with a T64 & intercooler upgrade:
http://www.3rotor.com/chito.htm

Bridgeported

I would suggest just getting the engine in the car and running properly before even doing any modifications to it. After it's in and running, then pull it out and mod the hell out of it!

You won't need to get extra dowel pins put in unless you are going to be going with a huge single turbo and looking for BIG power (over 700 hp). I have heard of guys making around 500-550 rwhp wtih a 20B using a streetport and stock twins pushing 15psi. I haven't seen it first hand or some dynos though, just talk.

When you pull it apart I would suggest getting a full rebuilt with Mazda parts, get upgraded apex seals (upgraded 2mm seals would be fine), and get a streetport done while you are at it. Have some work done to increase the engine oiling too.

jamesdeanrx7

thanks guys, hey bridgport one more question sorry but how much do you think it will cost to have a full rebuild mazda kit, upgraded 2mm seals, mild street port, bigger oil passages or somehting how much would all that be?

Bridgeported

I'm not sure if you can buy a full 20B rebuild kit directly from Mazda or not.
To get everything you need for the rebuild (with upgraded 2mm seals), all your other seals and gaskets, will probably run you in the neighborhood of $900-$1200 USD (for a 20B). Kurgan and Evil Aviator (among others) can give you a more definite figure for this, I know Evil knows for sure.
Streetport is free if you do it yourself, or maybe $30 if you buy templates to do the porting instead of free-hand. Same with doing coolant/oil passages honing and stuff like that.

jamesdeanrx7

SO I can get templetes from any performance shop of rotary's? I would love to do it my self is there any kind of book that shows how to do the oil and coolant i can do the street port. hmm.. i will have to do some searching when i get my motor. thanks i will check with evil aviator

Evil Aviator

Yes, but it only costs about $100 per rotor to get a street port, so there's not really much point in going through the trouble of doing it yourself. However, you can get templates and tools for porting if you really want to try it on your own.
http://www.mazdatrix.com/toolport.htm
http://www.racingbeat.com/FRmazda2.htm

Actually, j9fd3s is our resident parts number guru.
https://www.rx7club.com/forum/showth...hreadid=107070

BTW, if you like James Dean, note the any of the 550 Spyder kit cars can be easily modified to accept a 13B.

jamesdeanrx7

Ya I know thought of doing that to those cars are light as hell but i dont want to fal in the same fate as him you know what I mean lol.....thanks aviator I will talk to him as soon as Im ready 100 bucks thats not bad to have it done professionally.

jamesdeanrx7

Ps... Aviaotor was curious i keep reading htat the 20b is hard to get running becuase of all the sensors from diff parts of the car. But how do they fool the sensors or is that why they use a stand alone magement system like haltec etc.. just curious and do you still have to use the stock ecu but rewire it for the stand alone system?

jamesdeanrx7

P.s.s. Aviator Im sorry just one more question how much does an fc with a 20b conversion with heat a/c etc. and 450hp also an fc with the same sell for on the performance car market $20,000 to $30,000 or more what do yoiu think.

Evil Aviator

Yeah, but it would be really cool up to that point, hehehe. Besides, a fiberglass 550 Spyder with a stock $1,000 J-Spec 13BT could have just about the same power to weight ratio as a 20B-REW FC. The only problems with the 550 would be the rear engine handling issue, and the lack of a good roof to keep the rain out.

That's $100 per rotor, so it will be about $300 total, depending on which shop you take it to.

I think it's better to just install a standalone EMS. The standalone will run the engine better, anyway, and includes a lot of nice options like datalogging, AFR readout, electric fan switch, turbo timer, etc. Besides, most of the 20B engines in the US do not include the stock ECU, AFM, or ignition system. The only person on this forum who bothered with the stock Cosmo ECU was now, so you will need to check with him for all of the modification details.

It will probably sell for around 1/2 the amount of money it costs to build, which isn't too bad as far as hotrods go. This is the only one that I know of for sale at this time:
http://www.efini.net/rx7s4sale.htm

BTW, you don't need to address questions directly to me. There are quite a few people on this forum who know a great deal more than I do. Hopefully they will also add thier opinions, which may not agree with mine.

Turbo 3

iTrader: (3)

Since you are in Las Vegas go speak with RETed and he can most likely help you more than any of us first-hand with both a Haltech setup and porting to get you running right away. (not that I'm a fan of Haltech's)

jamesdeanrx7

oh... Reted lives in vegas I shall hit him up as soon as Im ready hehe..

Node

iTrader: (1)

450hp is probably possible on a stock port 13B-REW, so I'd have to say yes

and RETed is in Hawaii still afaik. Nice long vacation?