Rebuilding a NA8

Engines, Transmissions & Final Drive questions and answers

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Haydos
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Re: Rebuilding a NA8

Postby Haydos » Wed Aug 10, 2011 10:41 pm

Both, and chassis bracing. Like the mx5 it is a very well sorted chassis and didn't have much body roll to begin with. So it is possible that even though it wasn't very noticeable it might have been a worth while improvement. Though at this point i am very happy my cars handling but would enjoy a little more power to help pull away after the corners.

project.r.racing
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Re: Rebuilding a NA8

Postby project.r.racing » Wed Aug 10, 2011 10:55 pm

then rebuild iy like i post much earlier. add some mild hla friendly cams and shave, polish and port the head. will add 15kW to your fun. drivability will be same as normal. porbably put a heavy duty clutch in also.

or do all the other shiz for 60kW, and cross you fingers it'll like you in traffic.

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jerrah
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Re: Rebuilding a NA8

Postby jerrah » Thu Aug 11, 2011 9:37 am

Haydos wrote:i cannot see that the suspension in the MX5 can be made that much better with such improvements.

Racing beat hollow front and solid rear was one of the most signficant improvements I've done to my MX5. It was a night and day improvement and on the track I could easily drive around the inside of equal cars (without sways) in the bends.
Haydos wrote:The rebuild is definitely more about refreshing the car than increasing the power.

If it's just a refresh and not for power why not just buy a low km import engine? My B6 was a bit tired so I dropped in a 2001 B6 (in 2007 I think it was) and it was like a new car! Cost for a good one is about the price of a set of cams. When I've pulled the head the bore looks like it's just left the factory!
1991 MX5

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jerrah
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Re: Rebuilding a NA8

Postby jerrah » Thu Aug 11, 2011 9:49 am

Haydos wrote:My mate and I fitted whiteline sway bars to his Honda civic vti-r and while it made a slight improvement it was barely noticeable.
How much bigger than stock sway bars? The OEM sways on my NA6 looked like twigs compared to the items I upgraded to. Also you won't notice a the difference in sway bars unless you push the car in the corners. Driving around at commuting speeds you would hardly notice but there would be a benefit. It all comes into play when you start to push the car.
1991 MX5

toppertee
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Re: Rebuilding a NA8

Postby toppertee » Fri Aug 12, 2011 5:01 pm

Just had a bit of a read through.

If you are a little worried about the motor.
Why not just do a simple compression test. If that is all ok spend the money on a leak down test and a oil pressure test which will give you a better idea of the condition.

If all was ok, keep the motor. Good tune up leads spark plugs. etc...

Add some bolt on bits.
A light'n fly wheel, helps it rev much better. (same reson why the 1600 does)
New Clutch if needed
good induction kit.
Headers and the rest.
Your good to go.

The stock motor is a good'n. Goes really well.
A good second hand late model unit would only cost $1500 and last for years.
I.M.O

Good luck with it all

evil_weevil
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Vehicle: NA8

Re: Rebuilding a NA8

Postby evil_weevil » Thu Aug 18, 2011 10:52 am

This thread is a dam good read.
lots of great info.

to give you an idea - my MX5 is road rego'd but i use it for track days.
All I have is a full exhaust and mania intake for power.

After my last track day the car felt sluggish, I did a comp test and came back with 105-110psi across all four. seemed odd. spoke to a few people who sugegsted I do other stuff.
I had it in my head I needed a full rebuild and cost the earth and my wife would kill me.

so i took these suggestions on board - got another comp test done by someone else, and had them look into these other scenario's that people had suggested.

turns out the exhaust cam had skipped a tooth with my timing belt. so got a new kit, a tidy up service etc and car feels a million bucks
sure its still not quick in a straight line (last wakie day I had an IPRA swift GTI kill me down the straight thats when I knew something was up!)

so my advice, take on all what people have said - have a think what you want out of the car.

I know Im never going to be up the front of the pack with MX5 racing, but Im having fun out there.
I think If I were to go a bit more power, id get some cams and an ECU. but no point having the power if the other gear isnt up to standards!
i.e. get some sway bars, bushes and coilovers/springs and some new brake rotors. car will feel beter that way too.

hell Id even consider buying a VVT motor and putting that in.

now just to have a drive of Dann's car.... :D
Looking for an SVT motor for this:
viewtopic.php?f=73&t=62834

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NitroDann
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Re: Rebuilding a NA8

Postby NitroDann » Thu Aug 18, 2011 11:08 am

Where are you from? Ill give you a drive.
Gonna be a wakefield on the 4th?

Dann
http://www.NitroDann.com

speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

evil_weevil
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Vehicle: NA8

Re: Rebuilding a NA8

Postby evil_weevil » Thu Aug 18, 2011 11:32 am

I'm hoping to go to the Newie meet!
Looking for an SVT motor for this:
viewtopic.php?f=73&t=62834

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NitroDann
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Re: Rebuilding a NA8

Postby NitroDann » Thu Aug 18, 2011 12:32 pm

Well that solves that :P

Dann
http://www.NitroDann.com

speed wrote:If I was to do it again, I wouldn't even consider the supercharger.


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