Jump to content

boosting an FC RX-7,and another waste gate Q.


Science Abuse

Recommended Posts

First off, Turbo with no waste gate just runs balls out, max boost all the time, right? So no tuning ability?

 

Second, 2nd gen NA RX-7, manifolds and TB posrted, 120k miles, never been apart, how much power can it take? Looking at one for cheap, already runs low 14s n/a, how much boost can I put to it?

Also, its set up for dragin, how much can I expect to spend on good/agressive springs/shocks?

sorry I have so many questions, I'm new to these, and I need a race car! :D

Link to comment
Share on other sites

from what i understand the N/as havea much weaker body, so the handling u love from a turbo II probably won't be there. the compression on the motor is higher since its N/a to turboing it is tricky.
Link to comment
Share on other sites

my friend josh turbo charged his car, it's an n/a rex he did all his handling mods and everything but right now he's running like 5 pounds of boost i think...i THINK he's running the 14b turbo, i THINK. I'll find out more and post for you.

 

T.c.

Link to comment
Share on other sites

Guest relvinnian
Originally posted by LaserRSguy:

my friend josh turbo charged his car, it's an n/a rex he did all his handling mods and everything but right now he's running like 5 pounds of boost i think...i THINK he's running the 14b turbo, i THINK. I'll find out more and post for you.

 

T.c.

Josh is not seeing boost correctly yet. He only likes to work on it with me there, so it's been a slow process ;) . He is using a stock S4 RX-7 turbo, which is slightly modified.

 

Anyways, the amount of boost you can run is dependant on many factors. Hit me up on AIM, and I can describe the potential for you.

 

Main problem will be the n/a drivetrain which is very weak.

Link to comment
Share on other sites

Guest relvinnian
Originally posted by FC_Iria:

</font><blockquote>quote:</font><hr />Originally posted by BlackBird:

ok, I am getting a spare 13B with it...whats the recipie for a bullit proof 13b?

Thanks

Eric

1 piece ceramic apex seals :D </font>Umm no sorry smile.gif .

 

If you want the right recipe, hit me up on AIM, as I am sick of typing technical posts on forums.

 

For one thing, if you want the true power potential of the engine, you'll need 4-port housings and a 4-port intake manifold. 6-port engines do not see nearly the benefit of overall flow as well as timing changes due to port design. Even race built n/a motors use 4-port turbo housings (or peripheral housings ;) ).

 

This isn't to say that you can't make power on a turboed 6-port, it just does not have near the potential due to the limited design of the end plates. I've seen as much as 330bhp on race fuel with a stock turbo and 6-port engine.

Link to comment
Share on other sites

Originally posted by FC_Iria:

</font><blockquote>quote:</font><hr />Originally posted by BlackBird:

ok, I am getting a spare 13B with it...whats the recipie for a bullit proof 13b?

Thanks

Eric

1 piece ceramic apex seals :D </font>Don't forget to super glue them in :D

 

Please don't take that serious people.

Link to comment
Share on other sites

Guest relvinnian

1. Adkings sucks.

 

2. Used, great condition 4 port side housings can be had cheap. Same with rotor housings. Rebuild the engine yourself, it is cheaper, and from what I've gathered from reading your posts, it will not be a problem for you. The engine is held together by 18 tension bolts, it can't be that hard ;) .

 

3. Do research on port design, or buy a proven template. One thing to realize is that rotaries absolutely THRIVE on overlap and therefore free-flowing supporting systems. Yes, even turbo-rotaries. No 2.6l piston engine I know of can match a peripheral port in VE% SPREAD OVER A LARGE AREA. PPs tend to see 120-135% VE% @ peak. A heavy overlap street ported 13b can see 105-110% VE% @ TQ peak, but the curve is less than impressive. A half-bridge will see 105-110% VE% @ torque peak, but torque peak will shift up and torque curve will be much broader.

 

4. Ceramic apex seals ARE tougher, but the drawbacks are not worth the hassle. They cost approx $250 a piece (x6) :eek: . They will resist detonation, but they still are far more prone to breaking than a conventional piston engine. When they do break the ceramic pieces destroy almost everything in thier path, which includes rotor housings, rotors, and turbine wheels. ANYTHING one piece will not seal as well. There are Ianetti 2-piece ceramics ($$) which have also been proven to seal inferior to the mazda 3 piece 2mm apex seals.

 

I have done alot of research on apex seals. The only two viable apex seals in my opinion are the mazda 2 piece 3mm apex seals, and the mazda 3 piece 2mm apex seals.

 

3 piece 2mm apex seals seem to be the apex seal of choice for anyone running a 13b at power levels of 600rwhp or below. They seal better due to the 3 piece design, and have less rotational inertia. Although it may seem like a small problem, 2 piece 3mm apex seals "skip" or "chatter" against the rotor housings at lower rpm which increases wear and reduces low-end hp. The 2 piece 3mm apex seals seem to be used by all out drag cars running 500-900rwhp on a 13B.

 

The problem with buying an N/A is that everything on the turbo 2 is better. The turbo has: 4-piston brakes, very strong tranny/diff, all proper internals, higher flowing ports, much higher flowing intake manifolds, 5 lug hubs, etc.

 

I recommend buying a blown T2 and going from there. I saw one the other day very nice black 90 T2, huge fmic, upgraded turbo, ecu, fuel, with blown coolant seals: $2500 obo.

Link to comment
Share on other sites

I was thinking breifly of a T2,but this will be a second car, and I'm afraid to see what another sports car will do to my insurance :eek:

Ben, cooja grab a price off that N/A? Under a grand would be good :D Since tiss will be a car built for turns, the rear wheel toe'in option is a plus, was that just offered in 87-88?

Link to comment
Share on other sites

Guest relvinnian
Originally posted by BlackBird:

I was thinking breifly of a T2,but this will be a second car, and I'm afraid to see what another sports car will do to my insurance :eek:

Ben, cooja grab a price off that N/A? Under a grand would be good :D Since tiss will be a car built for turns, the rear wheel toe'in option is a plus, was that just offered in 87-88?

I am 19 with a reckless op, 2 FRAs, 1 at fault accident, and 1 speeding ticket. Insurance for both my cars for 6 months is $500 for liability. I can't imagine you being too much worse, but who knows I still think I'm a great driver compared to some smile.gif .

 

BTW, the DTSS is in all 2nd gens, and is really annoying smile.gif .

Link to comment
Share on other sites

dude, i pay a grand every 6 months for my Tbird, only have about 8 speeding tickets, in the last 2 years. :D And I know I'm a better driver then most, no accidents...oh, and I've been trained. lol

 

well, back the building a 4 port, i found this:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=1852474936

waday think? using tot he exhaustports to gauge life seems a bit daft, but it seems like a good deal, great for a rebuild.

Also, this kit:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=1852812495

It runs down the # and specs for the parts...and I'm lost. lol

 

[ 23 August 2002, 09:19 PM: Message edited by: BlackBird ]

Link to comment
Share on other sites

Originally posted by relvinnian:

</font><blockquote>quote:</font><hr />Originally posted by BlackBird:

I was thinking breifly of a T2,but this will be a second car, and I'm afraid to see what another sports car will do to my insurance :eek:

Ben, cooja grab a price off that N/A? Under a grand would be good :D Since tiss will be a car built for turns, the rear wheel toe'in option is a plus, was that just offered in 87-88?

I am 19 with a reckless op, 2 FRAs, 1 at fault accident, and 1 speeding ticket. Insurance for both my cars for 6 months is $500 for liability. I can't imagine you being too much worse, but who knows I still think I'm a great driver compared to some smile.gif .

 

BTW, the DTSS is in all 2nd gens, and is really annoying smile.gif .</font>

who in the hell do you go through. i am 21 with less than you (i have 2 acidents and 4 tickets, i think, but no fra's or reckless ops, i consider that less) and i pay 40 bucks more than that for liability on one car ever 6 months. n/m, i know why, allstate sucks my balls, thats why, i really need to insurance shop. :mad:
Link to comment
Share on other sites

Guest relvinnian

I go through permenant general (a1 general). They aren't exactly top notch, but I've handled a claim through them when I had my accident. They paid me a cool 8200 when my eclipse was worth around 6500-7000 in the condition before the wreck. That's really all that matters to me smile.gif

 

FRA is driving with no license and insurance I believe. Not sure on the exact definition, but it relates to that.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...