I dont know if this has been posted yet, I dont visit this part of the forum very often, but how hard is it to swap a n/a engine out of an FC? My friend has a GSL-SE and he wanted to swap the engine to try and get more power out of it. He also wanted to know if he can use the distributor with the newer engine and ditch the crank angle sensor. Is there a web site with this info? A thread you can point me to? Thanks.

 

those engines suck.
(i researched this alot and was planning to do it)
First of all they are 6 port, they have very very small center ports that are difficult to enlarge and the other ports arnt any better.
plus you cant port the exhaust at all because there is a diffuser in there to change the sound.

the only good thing is that 89-91 have hi compression rotors.

stick with your 12a

 

It can be done...ie all the TII swaps into FBs. As for the crank angle sensor, why would he wanna sub that for a distributor?

 

The guy has a GSL-SE so he already has a 6 port 13B

... I don't know if theres a great deal of difference between the basic GSL-SE block and the FC one ?

 

GSL-SE already come with 13B 6ports.


I think he wanted to stick with the distributor so he doesnt have to swap out all the ignition components. It was just an idea. The least amount of things for him to swap, the better.


Doesnt the GSL-SE block come with 3mm apex seals? FC engines come with 2mm. The intake manifolds are different on the FC and flow better.

Series4 engine has roughly 10hp more than the GSL-SE engine and series5 has roughly 20hp more than the GSL-SE.

 

The SE and N/A Gen II motors are both 6-port, although there are some minor, but significant, differences. However, the SE and 86-88 motors have the SAME compression ratio! That did not change until 89.

1 - The housings are not interchangeable because of the locations of the water O-rings
2 - The apex seals are different
3 - yes, the primary ports are slightly smaller on the Gen II motors
4 - the Gen II exhaust ports do have the sound baffles, but they can be cut out when you port it - it's just a PAIN, that's all!

The stock horsepower is not significant unless your friend is going to transfer the whole engine and ECU/harness - the 86-88 increase was due to intake and ignition mods that Mazda made, while the 89-92 increase was a combination of a recontoured intake, lighter rotors and increased compression ratio.

The SE dizzy will work fine if he doesn't want to go through the trouble to convert to the Gen II ECU.

His SE front cover and oil pan will have to used when he does the swap, and he will have to block or modify the emissions crap on the top of the center housing because the SE intake will not clear it easily.

 

Thanks diabolical1!

So if he doesnt change the ECU all he basically needs to change is the short block and use the GSL-SE intake manifold? How hard is it to swap the FC tranny (if the SE's tranny wont hold up)? Sorry for all the questions.

ps.
Is there a web site with info on a swap like this?

 

unless his current engine is dead I can't see the benafits of doing the swap ... as is said above most of the gains are in the induction system and engine management ... seeing as he'll ditch these when doing the swap it probably won't gain anything over a stock GSL-SE engine

 

Thanks. I'll let him know.