WE3RX7

iTrader: (8)

Well moving along with my GSL-SE project, I've come across a few questions. And although I'm familiar enough w/ the FC 6 port engine, I'm curious if they are the exact same as the earlier GSL-SE.

What RPM does the actuator begin to rotate and at what RPM is fully open?

Looking at the port timing, it would seem that removing the actuator sleeves all together, might be worth it. I'll lose that lower torque curve, but would think that on a stock ported engine, the powerband would come on sooner. Anybody try this yet?

I guess my question is - mine are stuck, do I clean and put back in as OE functional devices, or just remove all together?

Also, is the GSL-SE a 2mm or 3mm apex seal engine and what is the compression ratio? I'm debating about rebuilding it in the summer and throwing some S5 rotors in...

gsl-se addict

iTrader: (3)

The GSL-SE 5/6 ports are just like the S4 ones (operate on exhaust backpressure)

Personally, I would clean them and put them back in. If you pull them, it is like having them open all the time. Top end will be basically the same as before, but you will lose low end. Some say the loss in low end isn't noticible, but they are there for a reason. If you compare the peak torque RPM of the SE to the 12As, you will see that the SE gets up to peak torque sooner. With the peak power later or the same as the 12A. This equals wider powerband.

The SE has 3mm rotors, 9.4 compression, heaviest 13B rotor. The S5 rotors will give a bit more compression and less weight.

WE3RX7

iTrader: (8)

Thats what I was assuming - I left them in on my S4 FC but had to wire them open due to full exhaust. I honestly never noticed a loss in the low end. I'll probably leave 'em in.

I dont want an all out project car like my FC, just a fun beater. Drop-in filter, port match everything w/ full RB exhaust should be fine w/ me. Thanks for the info. If I rebuild it in the summer, I'll throw a mild streetport on there.

Rxxx-7_GSL-SE

to get full benifits you have to take the lim off to take the sleeves out, they are kind of like venturi inserts reducing the bore of the intake runners.

If you take em out your top end in increaced and your peak torque is moved at least 1000rpm higher.

I drove an FC with a steetable header and dual fart cans only till 4500rpm during its break in a the low end is just fine.

WE3RX7

iTrader: (8)

Something else I'm going to look at actually is to maybe use RENESIS sleeves. I have some laying around from a different project and I'll have to see if they'll fit. That would be pretty nice - the renesis sleeves are smoothed out and have a "lifter" at the end to straighten the airflow into the engine.

I'm pretty good with these cars, just never had a GSL-SE before and wanted to make sure there wasnt much difference before playing around.

85 FB

The 5/6 ports open up at about 3800 RPM under load. I cleaned mine out but haven't really noticed a true improvement. Maybe I need new actuators.

bugman1973

you could always look up some of my old stuff and mod the actuators to open when ever you want them to.

bugman1973

try this https://www.rx7club.com/1st-generation-specific-1979-1985-18/air-pump-operated-gsl-se-6th-ports-how-do-i-do-253169/page2/
this a a thread showing what i did to my actuators. i can adjust them to open at any rpm i want. the system actually works pretty well. ill be going with something else later but thats not till i get the microtec and everything else on it first. but i will let you in on what is going to be done. have you heard of something like a manual vtec controller. i going to have it wired in to the coils somehow so that at which ever rpm i want it at they will open. even if i want to change it while im in the car driving.