Can the early 13B rotors used in a turbo block? There seems to be some debate on this. Some people claim that the housings are very slightly different (few thousandths of an inch). Mazdatrix says they build 1st gen motors with s5 n/a rotors in them so I would think the gsl-se rotors would work in a turbo block also. Anyone here using this combo?

umm why?

I wouldn't even bother, not worth the risk to me.

It is stated in the Racing Beat catalog & tech tips guide that the GSL-SE 13B had different shaped housings and that the rotors & housings should NOT be mixed with parts from other model 13B engines!



It's a very good little book. I highly recomment getting one & reading it.

yeah, why do you want to put the crappy heavy rotors in?



mike

Because lots of racers use the SE rotors in thier T2's all the time.

Because lots of racers use the SE rotors in thier T2's all the time. [/quote]

yeah, I am not sure where all this hatred for gsl-se rotors is coming from? Why do it? Because I might have a pair handy. Because they result in a quicker spooling turbo and more low end torque. And I would prefer to have the 3mm seals when I get my turbo upgrade. Please don't get into the 2mm vs. 3mm crap. I just wanted to know if someone on this forum has done this.

i know of a bunch of people who have done it. seems to work just fine. i just dont see the point, s4 na rotors have 9.4 compression without the wieght penalty. of course if you must have 3mm seals getting 74-85 13b rotors are the way to go



mike

I am glad to hear you know a bunch of people who have done it. I see your point about weight. But my gsl-se redlines at 7k rpm so it is not that much of a penalty. With the set-up I currently have, I won't be revving over 7k rpm anyway. I have a 2nd gen n/a and a gsl-se and the difference in initial acceleration is significant between the two. If you have driven both you know what I am talking about.

the se will accelerate faster because it is alot lighter. I know what you mean though, i had a gsl-se also... but my t2 launches about 10x harder than the se.. lol.



gsl-se 1/4: 16 or so

t2 1/4: 13



but by dang it! That gsl-se was the funnest car. There is something about the first gens thats fun. I would really like to buy another, but its just not practical for me right now :(

I am glad to hear you know a bunch of people who have done it. I see your point about weight. But my gsl-se redlines at 7k rpm so it is not that much of a penalty. With the set-up I currently have, I won't be revving over 7k rpm anyway. I have a 2nd gen n/a and a gsl-se and the difference in initial acceleration is significant between the two. If you have driven both you know what I am talking about. [/quote]

yes, thats true, but i have a gsl-se with s4 rotors and a light flywheel and its so responsive, it revs like mad



mike

I definately wouldn't recommend it and not just because of the added weight, (which by itself would stop me from considering it).

It's the compression ratio that you should really be worried about.

The non-turbo SE rotors are going to run your compression up to the point were you will be in real jeopardy of detonation. I don't need to tell you you don't want that. With the non-turbo rotors it'll https://www.nopistons.com/forums/pub...R#>/unsure.png just a matter of time.

My advice:

Stick with your lighter, righter, rotors.

What are you looking to do with the car the motors going in...? Just drive it on the street, or race it HARD at the track.



87-88 TII rotors compression=8.5

89-91 TII rotors compression=9.0 (big friggin' jump)

84-85 13Bn/a compression=9.4 (even bigger friggin' jump)



There's PLENTY of tricks you can do to hinder detonation. TUNING IS KEY.



SE rotors would be like utilizing a heavier flywheel, (which many DRAG racers do) with the benifits of HIGHER' compression.



RacingBeat says: "If you intend your race engine to run above 8,500 RPM *or if the engine is a non-standard assembly, we recommend balancing the rotating assembly. The rotating assembly includes both rotors, main pulley, front and rear counterweights. and the eccentric shaft. We also recommend balancing the pressure plate and the flywheel on the rotating assembly.



In our experience it is not necessary to re-balance a stock or mildly modified engine operating below 8,500 RPM if the rotating parts were originally intended by Mazda to be used together."



****... for $317.00 you could score a pair of good TII rotors and play it safe. It's DEFINATLY a journey into a trial and error experimentation area, unless you've done it before... but then you wouldn't be asking the question.

Oh... and I've asked Atkins about the benifits of milling a rotor to 3mm... and their response was... NO benifits and totally unnecessary. It is done when a 2mm seal can no longer be accepted by a used rotor because of minor damage to the apex groove.

My bare bones 2nd gen n/a is only 200 lb. heavier than the GSL-SE but it just feels like the 2nd gen n/a was a step backwards comparing it to an SE. Now a t2 is a different story. If you think your t2 is fun, you should get a turbo GSL-SE like mine https://www.nopistons.com/forums/pub... . Those launches get a little tricky though.

My bare bones 2nd gen n/a is only 200 lb. heavier than the GSL-SE but it just feels like the 2nd gen n/a was a step backwards comparing it to an SE. Now a t2 is a different story. If you think your t2 is fun, you should get a turbo GSL-SE like mine https://www.nopistons.com/forums/pub... . Those launches get a little tricky though. [/quote]

i'm thinking about it https://www.nopistons.com/forums/pub...#>/biggrin.png



mike

Don't think, DO IT!!! https://www.nopistons.com/forums/pub...1047683827.gif

He will.With him its only time.

yeah, i need a manifold, that will clear the 6 ports...



mike

I have a set of fd rotor housings would there be any problems putting them in a S4 NA?

speaking of manifolds, can you use the t2 lower intake manifold with a 6-port block with a little port matching? That would solve your exhaust manifold problem, correct?

hey, i'll trade you my s5 9.7 compression rotors for your fd rotors. That'll give you more power than the fd rotors.

sorry I dont have FD rotors just the rotor housings

How much for the housings?

speaking of manifolds, can you use the t2 lower intake manifold with a 6-port block with a little port matching? That would solve your exhaust manifold problem, correct? [/quote]

nah i want to keep the working 6 ports, i dont want to use a stock turbo anyways



mike