FD "n/a" engine.. any good?
 

hi everyone, the 12a engine in my sa22 failed just recently, and i really dont want to have it off the road for long, so i've been looking at some other options to drop straight in, in the meantime

one of the more interesting things i've seen is a series 7 engine which someone has taken the turboes off of, and fitted a holley carburetor. the engine has low k's since a rebuild, and the price is very good - less than the usual s4/s5 n/a engine

so the obvious response is "holy heck why would you do that, it'll be making less than half the power of stock", but i'm attracted to the fact that it'll bolt in without me having to alter wiring, install intercooler plumbing, or alter the fuelling system. and the components will have less wear than a 20th-hand, 20th-"rebuild" rx4 13b or similar.

i've read that the compression ratio is 9:1 on these engines (vs 9.4:1 for a real n/a) , so i assume its not as bad as trying to drive around with a piston engine that you've just taken the turbo off of. plus i like being different!

anyway, thoughts/opinions? i havent bought the engine or even contacted the seller yet, so i won't lose face if you tell me the idea stinks. just putting it out there, cheers

I don't know about your statement of "just bolt in".The mounts are going to be custom,and it may be a problem transmission wise.
BUMP anyways ,it'll get more replies.

sorry, by bolt in i meant with the use of an rx4 sump and the correct front cover.. i was under the impression that the 12a and 13b could mount to each other's transmissions without a problem?

correct.

well thats one less thing to worry about then

but my first question still stands, (and i suppose there's not many people who could answer from experience)

what can i expect from a de-turboed 13b, still using the low compression rotors? i think it'd be a shame to have a fancy new(ish) engine in my car, only to have it make miserable power, poor emissions, run hot and suck gas, etc

basically i'm still tossing up whether i even want to run a 12a or 13b, let alone buying good engines/buggered engines/rebuilding my current engine. ultimately i'm lazy, so leaning towards "drop in and go"

There is a thread in the 2nd gen time slips section where a guy made 184rwhp with a street ported s5 turbo engine running NA.
Both S5 turbo and FD have 9.0 CR rotors.

sounds like its definitely worth a go then!

anyone have an idea on the clutch/flywheel combo i'll need to mate it to a 12a trans? im guessing everyone else putting a REW into an sa22 uses the gearbox that comes with it, but a de-turbo'd carby one isnt exactly going to be a box smasher so i reckon i'll get away with it

Depends on your application. I break boxes with N/A. I was wrecking them with stock port 12As.

Because you're probably not like me where you could break a crowbar in a sandbox, you can bolt a S5 N/A flywheel onto that so you can use an N/A transmission.

Low comp rotor's are fine for n/a use, Im using s413bt rotor's in my n/a set up now, Easy starting, Good on gas, It's all in how it's set up/tuned. I no who built that motor too, And if i had the cash i'd be getting it.

13Bs used to have 9.2.

Judge Ito made something silly like 242whp on turbo rotors N/A and only 10 degrees of timing.

I remember reading that somewhere, And that was a PP motor to i think ??
Also this guy off rotary car club made 216hp on s4 turbo rotor's : http://*************.com/rotary_foru...ead.php?t=8550

The benefit of having an S5 or newer engine will be parts availability and better chrome.