decisions decisions.. NA or FI

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irwin83r
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decisions decisions.. NA or FI

Postby irwin83r » Sat Nov 22, 2008 2:28 pm

hey all.

kinda in two minds.. and just after some opinions/thoughts as i cant quiet make up my mind..

the saga!

ages ago i bought a set of tomie pon cams and an inner shim kit with the intention of doing a mild port and polish job my self on my current head and running it with a plug and play ecu. i then came across a decently priced nb8a head so snapped that up since it would mean id have one to work on while the other stayed in the car. i also then came across a hlatec E8 going for a reasonable price and figured what the hey..
talking to a local head guru ages and ages ago he was quiet happy for me to come be his apprentice for a week and do my own head on his flow bench unfortunatly Mr Lord passed away after an accident on the huntly hill climb.. however his brother put me in touch with a friend of his that bought his flow bench and equipment, so i left my head with him to play with.

more recently at the AASA mx5 challenge i sheered my crank shaft/alternator pully key. i was able to scab a replacement of someone elses motor who had siezed No4 so got the car running again only to find id killed a spark plug lead or 2 and was running on a questionable number of cylinders. (still raced last race sunday :D had an awesome fight for 2nd last place lol) when replacing the key i noticed the keyway was now sloppy which means it will prob kill another key. so... needed a new crank shaft..
then i noticed a well priced nb rebuild kit with crank and high comp pistons for sale. so grabbed that.

more recently a friend of mines farther converted his nb8a to electric (yes i know wtf in deed) but in any case he sold me his old standard motor.

and more recently again! my Prod sports legal turbo kit has come together.. (which i have a spare one of if anyone wants to buy)

ok.. so my delema is.. do i as orginialy planned put the flowed head with cams ecu on the standard bottom end and rebuild the dodgy cranked bottom end with the parts in the rebuild kit making a high comp Nat asp bottom end swap that for the standard bottom end then get back on the saving train and start getting parts for a strong FI bottom end for the year after next. racing in supersprints club track days and any AASA events i can get into over year coming.

OR do i put the flowed head on the standard bottom end and sell the high comp pistons and buy some low comps and build a low comp bottom end using the rebuild kit. getting the car turboed sooner and changing racing classes..

pretty much i want to have a competative car and get on the track as much as i can.. i just really cant decide if i should use all the bits i have sitting in front of me right now to build a nat asp 110-120rwkw monster or stick with just a mild camed head and ecu for around the 100rwkw mark using most the parts i have to build a FI motor running around 180rwkw and racing the other sp race cars.

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Matty
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decisions decisions.. NA or FI

Postby Matty » Sat Nov 22, 2008 3:12 pm

No idea, but I have no pity for you if that's the hardest decision you have to make.

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decisions decisions.. NA or FI

Postby bark » Sat Nov 22, 2008 3:22 pm

Go FI, you'll never look back!

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decisions decisions.. NA or FI

Postby Rotary » Sat Nov 22, 2008 5:10 pm

I guess it depends a little on how much you want to spend.

F/I will probably need other upgrades if you haven't done so already(brakes etc)
and then put a strain on all components with more chances of failure. if money is no issue
then F/I

Otherwise build the engine with F/I in mind ie all power mods except the High Comp pistons,
and be ready for turbo later after enjoying it as N/a for a while.
This does depend on the how wild the Cam is, and wether it would be suitable for Turbo later.

Thats kind of what i'm doing now due to lack of funds to modify suspension and brakes, but also until my track driving skill improves.

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decisions decisions.. NA or FI

Postby Fuzzlet » Sun Nov 23, 2008 1:29 am

Put your flowed head on the standard bottom end and build a stronger one for turbo. By the sounds of it you're going turbo either way, so you may aswel spend most of your money on that. You could build a great N/A bottom end to eventually sell when you go turbo, but I can assure you, you will only get back around 1/4 of what you spent to get it there (I learnt that the hard way...)
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irwin83r
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decisions decisions.. NA or FI

Postby irwin83r » Sun Nov 23, 2008 12:46 pm

how much do you think youd get for a nat asp bottom end?

would the flowed head with tomie cams be suited to a fi setup? has standard valve sizes

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decisions decisions.. NA or FI

Postby Fatty » Sun Nov 23, 2008 1:04 pm

fuzzlet is right, if you reckon you'll eventually end up going the turbo route (and it sounds like you will) , it seems like a waste of time and money building an NA screamer in the meantime.

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decisions decisions.. NA or FI

Postby Fuzzlet » Sun Nov 23, 2008 1:39 pm

I'll PM u about how much for the bottom end etc, but a flowed head (even with standard valves) will still be useful when you go turbo. Just because the air is getting forced in doesnt mean it wont enjoy a smoothe ride in there :D
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Rotary
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decisions decisions.. NA or FI

Postby Rotary » Sun Nov 23, 2008 10:23 pm

As Fuzzlet said F/I will see Good benefits from Increase in flow, its the way to make big power on relatively little boost
With Cams and turbo the thing to be careful of is Overlap, and usually a turbo Cam will have big lift but not as much duration(and overlap) as a wild N/A cam.

Probably best if you qoute its figures, but if the CAM does not require many extra changes(springs, ECU etc.), then it will probably work well with F/I
and you could always tune it with Adj CAM Gears, for the right overlap and max power,
or just sell the cams and Get turbo ones.

If you really want to build the bottom end, build it with 9:1 Forgies and they would still work well with N/A and be good for F/I later
Last edited by Rotary on Mon Nov 24, 2008 12:56 am, edited 1 time in total.

physco88au
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decisions decisions.. NA or FI

Postby physco88au » Sun Nov 23, 2008 10:58 pm

PM me RE: Prod sports legal turbo and what it entails

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irwin83r
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decisions decisions.. NA or FI

Postby irwin83r » Mon Nov 24, 2008 5:07 pm

prod sports turbos are factory items untouched.. so SE or SP turbo and manifolds

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decisions decisions.. NA or FI

Postby Boyracer » Tue Nov 25, 2008 8:24 am

Really comes down to how much money you have as Rotary said...

1.You can build a mild NA engine with a stock bottom end and race for 3 or 4 years without touching it,

2.You can build a mild turbo set up...like my SE race cars...stick with lower boost...Run in Class C....will run for ages and not cost too much.

3.Spend a fortune building a Class B Turbo car...probably not the best option with limited budget and lack of experience.
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decisions decisions.. NA or FI

Postby Charlie Brown » Tue Nov 25, 2008 4:35 pm

I'd stick with NA for the reduced cost and to have more fun with others running a similar setup.

If you go the FI route then the big boys will eat you up because their pockets have a lot more folding stuff and the on track gap, even with your driving ability, will be too great.

Have a chat to Chris. He'll tell you what it costs to run FI. I know he's said he can run 2 - 3 NCs for the full season for the cost of running 1 SE.
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irwin83r
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decisions decisions.. NA or FI

Postby irwin83r » Wed Nov 26, 2008 5:35 pm

thanks guys.

yeah thinking ill stick with NA for a bit longer.. be waster really seeing as i have all the bits there i guess too.


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