Old school hottie build or forced induction?

Engines, Transmissions & Final Drive questions and answers

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3gress
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Re: Old school hottie build or forced induction?

Postby 3gress » Mon Nov 06, 2017 11:08 pm

Finding a low km 10:1 bottom end from a later model write off and spending the cash on ecu and headwork is an option that doesnt require much effort or excessive $$$. Won't be a time attack front runner but will be well capable of smile inducing spirited drives.
Starting with an already assembled bottom end is a pragmatic option which can then be accessorized with improved intake /exhaust/ecu and stay fairly close to budget goals.
Completely rebuilding bottom end doesn't guarantee reliability depending on who does the work..

manga_blue
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Re: Old school hottie build or forced induction?

Postby manga_blue » Mon Nov 06, 2017 11:20 pm

Good point. My NA8 block has run NB8B crank, rods and pistons for 10 years and a few thousand laps at 7600rpm and it's always been solid as. And then again I have seen two "professional" rebuilds that didn't survive one meeting.
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GR124
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Re: Old school hottie build or forced induction?

Postby GR124 » Tue Nov 07, 2017 8:40 am

I do LIKE this thread as I am debating the Turbo vs N/A in my head for the future.

speed
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Re: Old school hottie build or forced induction?

Postby speed » Tue Nov 07, 2017 9:14 am

Looks like the OP will need to source a good bottom end to stay within budget as 3gress suggested.

He could also part out his existing "spare" engine to recoup a little cash.
That will also give him the experience of stripping down an engine, which is always fun, especially when you don't have to put it back together!

It seems the must have parts is:
Good bottom end.
ECU/tune.
Minor head work.
Clutch?
2 inch exhaust?

Optional parts:
Manifolds.
Cams.
Exhaust.
Valves.
ITB's.

If the OP was to go turbo he'd need:
Turbo.
Exhaust manifold.
Dump pipe.
2.5/3 inch Exhaust.
Intercooler and piping.
ECU/Tune.
Injectors.
Clutch.
Oil feed and drain lines.
Boost controller.

Optional:
Brown undies



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NA6 turbo - 140kw atw - not the most powerful but so much fun :D

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StanTheMan
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Re: Old school hottie build or forced induction?

Postby StanTheMan » Tue Nov 07, 2017 9:32 am

speed wrote:
Optional:
Brown undies



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with NA he will have white soiled undies with a permanent hard on :lol: :mrgreen: but will not go as fast along straights
Satans Ride called F33nix the resurrected NA6

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Re: Old school hottie build or forced induction?

Postby greenMachine » Tue Nov 07, 2017 9:58 am

Been following this thread with a smile - been there, done that, got the memories.

The original GM was a dual duty car, 115kw atw, lovely noise, very entertaining on the road and quite handy on the track.

Even though it was not the daily, eventually the drawbacks of driving a 'hottie' in town started to take their toll, and after some years the plan was hatched to convert it back to civilian spec, and put the good gear in a 'proper' racecar.

I had great fun, and learnt a lot while it was doing the dual duty, and I would never try and talk anyone out of that. I would only caution them to be realistic about the drawbacks of such a car, and to think about what their exit strategy might be when/if they find themselves 'over it'. And then to get on with it, get it done as quickly as they can, and enjoy the ride!!

:mrgreen:

PS having a turbo now, I am in a position to compare - nothing matches the thrill of a responsive atmo car on the road. It is not 'all about the power'.
I never met a horsepower I didn't like (thanks bwob)

Build thread

NB SE - gone to the dark side (and loving it 8) )

3gress
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Re: Old school hottie build or forced induction?

Postby 3gress » Tue Nov 07, 2017 10:02 am

greenMachine wrote:
nothing matches the thrill of a responsive atmo car on the road. It is not 'all about the power'.


AMEN to that brother :NETPOINTZ:

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Re: Old school hottie build or forced induction?

Postby Magpie » Tue Nov 07, 2017 12:07 pm

3gress wrote:AMEN to that brother
Could ask the person who drove mine on Monday (me as passenger)...

"...Mark. Really appreciate the trust in letting me take the beast out. Got about half way through the session and started to realise I really, really like that car. That engine is addictive."

Image

3gress
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Re: Old school hottie build or forced induction?

Postby 3gress » Tue Nov 07, 2017 2:22 pm

You did offer to let me drive it on the Iluka road once Mark but way too much beast in that thing for me! 8)
I remember both our kids jumping about 4' in the air when you started it up..

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Re: Old school hottie build or forced induction?

Postby Magpie » Tue Nov 07, 2017 2:39 pm

3gress wrote:I remember both our kids jumping about 4' in the air when you started it up..
At Lakeside I run a very quite exhaust due to the noise restrictions. That exhaust you remember gets you black flagged at Lakeside, it recorded 103db and the engine was at about 6,500 rpm...

3gress
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Re: Old school hottie build or forced induction?

Postby 3gress » Tue Nov 07, 2017 3:24 pm

I would have loved to call shotgun on a couple of laps about Lismore CBD. I'd have been happy to pay the defects it would most definately attract if only for the look on the faces of the locals...especially the usual fart can lappers, not least though the more civilized members of the community. :DIY:

3gress
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Re: Old school hottie build or forced induction?

Postby 3gress » Tue Nov 07, 2017 3:35 pm

[youtube]... Http://youtu.be/ watch?v=WiJLgdZ365M ... https://www.youtube.com/watch?v=WiJLgdZ365M[/youtube]

If this link works it will give an idea of the aural awesomeness that my build provided when on its first road trip.
Bear in mind it was still being tuned and its first time at altitude, also a 6000rpm limit was imposed, it was using a standard base ignition map lightly meddled with and a 9yr. old was in company so i certainly wasnt going to be an idiot. Not the greatest idea to put negligent driving antics on youtube especially after winning full custody officially in the recent past.
Anyway turn the base up and bear with the in car commentary provided by my apprentice in awe of the scenery. You can find comments on the modifications somewhere down the page too.

Ok so i messed it up a bit but if you click on the second' https:/www.youtube.com/watch?...etc' bit you can see my 'escaped from hospital' altered physique but you should be listening more than watching anyway for what a budget and physical ability constrained build can be achieved. Not more than a stock block and lots of headwork, jenveys and such...and in a front wheel drive 323 astina with a considerable weight disadvantage comlared to an mx5. The same engine with another few grand In improvements is currently being installed in my '90 NA6 with priority toward weight savings including maintaining oem NA6 brakes, no power steer, no heater, blower, aircon, softop etc.

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Re: Old school hottie build or forced induction?

Postby manga_blue » Tue Nov 07, 2017 4:43 pm

speed wrote:Looks like the OP will need to source a good bottom end to stay within budget as 3gress suggested.

He could also part out his existing "spare" engine to recoup a little cash.
That will also give him the experience of stripping down an engine, which is always fun, especially when you don't have to put it back together!

It seems the must have parts for a basic fun build is:
Good bottom end.
ECU/tune.
Minor head work.
Clutch?
2.25 inch exhaust
Coolant re-route
Shaved flywheel
Better inlet manifold (NA8 or NB8B)

Optional parts:
Better exhaust Manifold.
Cams.
Valves.
No ITB's. Much pain, little gain


If the OP was to go turbo he'd need:
Turbo.
Exhaust manifold.
Dump pipe.
2.5/3 inch Exhaust.
Intercooler and piping.
ECU/Tune.
Injectors.
Clutch.
Oil feed and drain lines.
Boost controller.

Optional:
Brown undies



Sent from my SM-A520F using Tapatalk
FTFY, otherwise a very good list.
’95 NA8

3gress
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Re: Old school hottie build or forced induction?

Postby 3gress » Tue Nov 07, 2017 5:28 pm

]
I'd have to disagree on the ITBS opinion. The only real problem seems to be packaging decent length runners.
My torana with it's triple dellortoes made huge power attributed mainly to the fuelling increase. The injected multiple thottle bodies are not that far from the same concept; large throttle area allowing massive instant gains in response. I really hope a number of more serious contenders chime in with their opinions on the benefits of providing each cylinder with its own throttle body. It isn't just for the noise or bonnet opening insta-manliness. Travel back in time to Alpha romeo gtv induction or further to formula 3 engine set ups, on and on throughout motorsport history they have been implemented for their improvements in fuelling effeciency. Dirt track racers...Ford gt40 engines etc.
If the above link works it shows the absolutely riveting footage of the first start up of my engine when jenveys were first installed. Very litlle deviations from a standard modified engine were encountered to make it work. A vacuum log for map sensor, port for brake booster, not really accounting for painful experiences.
Seriously not trting to kick off a forum argument and please no itb verse turbo...we know who wins :lol:
But the individual cylinder fuelling concept is far removed from pigeonholes that bonnet pins on a street car and supercheap auto alloy wings belong in.
I have had nothing but pleasure from tuning my setup and it certainly wasn't to flash to the bro's at maccas.
More in line with why i stuck with the 202 6 cylinder rather than join the 308 brigade years ago, or now sending myself into poverty on a 4 cylinder 'hairdressers' car rather than a 'real car' like so many others like to poke fun at. The challenge presents itself, i get to educate myself and tinker on something.
That said, skinning cats can be an artwork or a real mess for all the effort applied.
As stated early on Madjak's intake manifold concept has the numbers, magpie's efforts are worthy of note also, just to mention a couple of catskin accomplishments.

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LiteIsRite
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Re: Old school hottie build or forced induction?

Postby LiteIsRite » Tue Nov 07, 2017 6:22 pm

Thanks for sharing, Dan. I agree your ITB build is a work of art, and the sound is awesome. Enjoyed riding along on the road to Dorrigo, too.
”How you get there is the worthier part.” - Shepherd Book, Firefly
"Cherry" - Classic Red 1990 NA6 :NA6: [sold]


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