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Discussion Starter · #1 ·
Now I know we all go F/I

but has anyone on here gone Down the route of N/A modifications

If so like what.

Other then the basics of Extractors and free flowing intakes.

I'm just interested to see what people have done.

Yes alot of the modifications done to a Turbo or F/I Fe can apply but I'm more interested to see if anyone knows of any more wilder N/A mods.

Here in Aus there are few in some Clubman type cars. In stead of the usual 4AGE 1.6L toyota Levin 20Valve - some option for the FE DOHC - for more mid range but the extra weight keeps them even on the track apparently but on the street a FE DOHC 2.0L clubman is alot better. The two cars I know still run totally stock ECU.

So any information would be interesting
 

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I've seen a few Dutch threads that have ITB's installed. If my memory serves correctly, they are from a GSXR.
 

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You would in fact reach higher power with shorter stroke on the FE engine; not perhaps nice power curve for driving around the town, unless you want people to think there's a motorcycle coming, but still...

RPM limitations with 94mm crank cap the available power quite severely, the block would have to be taller to accommodate longer rods and even then it could never run as high RPM as 77mm version. You'd get about 220-230 Nm and with 9k RPM limit you'd have very hard time going through 250hp.

With 77mm stroke and 89mm bore (barely acceptable for NA and you might have to fill the block) you would have 1.92liter engine, producing about 190-200 Nm. With custom 168mm rods and very short 25mm compression height pistons you could run MUCH higher RPM than with 94mm (I'd imagine 13k vs 9k), amply offsetting the lost displacement. You could get into 300's that way. And yeah, such an engine would have pretty short service interval.

We are talking about extreme modifications here, obviously!
 

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Discussion Starter · #7 ·
Yeah well I'd stroke it for more low end and driveability

but It's not on my cards unless I have to rebuild but even then I'd just buy another whole motor.

Nah I'm looking for where to go.
As I dont' plan to go much further then FE3N cam shaft for the intake to replace the FEAP one. but once I get a set of extractors made up.

I was thicking down the line for Fun and maybe a litte competition in the bracket class a 50shot of NOS.

but I've been looking at some Hi -modded Sr20De's here in SSS pulsars and some have some nice large cam shafts up raded comp from 9.6 to 10.5 and so fourth.

but they are all fitted into Lighter cars. Not a GV wagon!

Yeah I know everyone will say strap a turbo onto the side. but I already got a Mx-6 for that. I'm looking at something I can rev to 3500rpm at most every day to and from work and On the odd time just let loose. Which I did tonight next to a Honda Intergra . HE got scared when he heard this Wagon open up.

but all ideas are great and any information is usefull.
 

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maybe just get some adjustable cam wheels and the FE3N cam, extractors and some better valve springs..so you can drive it 'normal' most of the time and rev it to 8k if you need to...
 

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Stock stroke, ITBs, 8k limit, cams, manifolds, throttle, and a REAL CAI should = decent power (200ish) with a good tune. reliability would be acceptable at that level too.

Fred.
 

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I would like to se a 12:1 cr and some major intake and exhauast work. The car would drive like an all throttle go cart. I wouldnt expect over 250 ish with out alot of work done and some serious tunning.
 

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If you plan on reving it high, loke 10,000-12k you would want something like E85 or E100.
Care to educate my sorry arse about why that might be the case, or indeed why it might be the opposite to that.

You get better spark controle with higher quality fuels.
ey?
 

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If you plan on reving it high, loke 10,000-12k you would want something like E85 or E100. You get better spark controle with higher quality fuels.
Here in Oz we only have E85 atm, and its not that easy to come by as yet...only one outlet in all of Sydney....(though there are few in towns nearby)

Doesn't really suit a daily driver.

As for spark control......yes Ethanol burns slower so the spark timing needs to be different....and yes its less prone to pre ignition...is that what you meant by better control ?
 

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Motorcycles do 14-15k with regular pump gas, why would a car engine be different?
 

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Point was, the octane comes down to heat and pressure requirements, and not speed. The faster the engine is going the *less* likely it is to detonate. Thus at high revs you can get away with worse gas if all else is equal.

Also, better gas burns more slowly and is less suited to screaming if anything.

The correct tune will make it right almost no matter what though.

The fact is, high compression and rpm come together, but its only the compression causing the requirement for more octane.

Sorry for being a knob about it. It just winds me up when something is blatantly wrong like that.

Fred.
 

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My apologies for the misled drunken ramblings of last night. I was just tring to make the association of higher quality fuel and high compression with accurate and controled spark events.
 

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Discussion Starter · #19 ·
Had not been on to read this.

but I think the bore to stroke ratio and size of the pistons has something to do with motorbike engines reving there nuts off.

I personally like Freidos' Idea with out individual TB's

i was thinking more along the lines of a 200HP engine reving to about 8000rpm. with out too much loss down low. yes must loose some power down low with cams more sutied to top end.

but yeah i'm thinking instead of putting in some FE3N inakte cam. gettign some custom grind cams made up similar to a Sr20 DE stage two spec. I know Sr20's in stage 2 spec make around 190-230Hp flywheel depending on the compression ratio.

if anything I just want to do bolt ons and head work and not touch the bottom end. hell even not open it up if I can.
It's more a long term plan. basicly to see bit by bit bit. So like when i get time or thigns change etc parts come available etc.
 

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Had not been on to read this.

but I think the bore to stroke ratio and size of the pistons has something to do with motorbike engines reving there nuts off.
Yeah but the point was they don't need very high-octane fuel to do so. Also it's it's not the bore to stroke ratio, it's just stroke. I know way undersquare engines that run happily to 25krpm. They are model aircraft engines having 13mm bore on 19mm stroke.
 
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