Sunny Gti tuning??

[peter_261]

Please dont ba angry at me for posting about a non '-R but iv been looking about the net for some tuning info for the N/A Sunny GTi, but cant find any.just looking some tips incase theres any free horsepower floating around the head,manifolds etc.Its a racing car so dont worry about posting about rash bodges or anything!:lol:
If anyone could point me in the righ direction,i would be MOST thankfull! Cheers

 

[AJ4]

the nissan ali cast stuff is pretty crap ( heads, inlet manifold, throttle body ). I'd concentrate on those and remove all the steps and gaps etc. Pretty much everything else ( turbo, cams, exhaust etc ) is Pulsar specific...

 

[GTiR_Mic]

Hi mate, good to see the GTi is still out there kicking about. I had one before I got my GTi-R, for head work you are best to get racing cams (Piper do them) head ported, polished & skimmed, 421 manifold, full exhaust system, the list goes on.

Speak to Dragmea on here, he has the SR20DE(T) Micra.

He held the record for the fastest SR20DE engine in the world for a while, so he knows what to put into it. Sure it was running a good bit over 200bhp then 150bhp (At least) of Nos running through it.

Mic

 

[GTiR_Mic]

the nissan ali cast stuff is pretty crap ( heads, inlet manifold, throttle body ).

There is nothing wrong with the standard manifold on the GTi

Mic

 

[AJ4]

must just be ours that sucks ass then :lol: Actually, its not that bad, I just meant they dont line up too well at the flanges and need a bit of 'de-stepping'. The plenum design is pretty good and the throttle bodies are very poor

 

[peter_261]

thanks lads.oh i supposed i should have mentioned that its a racing car,and for the regulations the ports,valves and cams must remain standard.but thats handy knowing about the casting problems.cheers lads.keep any info coming,theres a g-limited MR2 that needs beaten!!:lol:

 

[AJ4]

The problem I found with the throttle body is where the butterfly spindle goes through. To stop the aluminium from wearing away they've cast a great bloody steel tube with sharp edges into the middle. Its a mass produced car and its cheap to do, but its not very good for performance, especially if its NA and you need all the airflow you can get.

Not sure what the idle and emmisions system is like on the Gti, but thats pretty bad on the Pulsar as well. There are all sorts of pipes and tubes bleeding and jetting air all over the place, probably a good idea to bin all that rubbish and fill in the holes if your going for all out performance.

 

[andrew]

all you need to know mate about tunning the sr20de engine..http://www.sr20forum.com/

here is what i have done to my gti

http://www.nissangtir.co.uk/forum/forum_posts.asp?TID=5210

 

[AJ4]

thats a good thread Andrew, very interesting read and very nice project 8)

 

[Dragmera]

thanks lads.oh i supposed i should have mentioned that its a racing car,and for the regulations the ports,valves and cams must remain standard.but thats handy knowing about the casting problems.cheers lads.keep any info coming,theres a g-limited MR2 that needs beaten!!:lol:

First of all, what is your budget?

You can get some decent power out of your high port engine, but it may get costly.

You best bet is to go for higher compression. This is done pretty easily by installing some pistons from the SR16VE engine (stock piston size of 86mm). These are available from Greg Vogel @ SR20FORUM (Mossy Performance). By simply installing the SR16VE pistons, you will increase the compression from 10:1 to 12:1, giving big gains right across the rev range.

Couple this with Hotshot (or SSAC if your money is tight) exhaust manifold, cut the secondary pipe off and install a 2.5" collector. Run a 2.5" exhaust system with minimal bends.

A big restriction on the old Sunny GTi engine was the airflow meter. With its small bore, it made making power on the NA engine difficult. You can rectify this by using a later Almera GTi MAF. The problem with this is that the Almera GTi MAF is not programmed for the Sunny GTi ECU. You can get by this by rewiring the loom to accept an Almera GTi ECU or by using an aftermarket ECU or piggyback unit. The Greddy E-manage unit is capable of this.

I found that the best air intake was an enclosed BMC filter with a 4" RAM pipe. This did wonders for my power output, and I managed to get 200.5 HP & 164 lbft from stock cams and 11:1 compression.

You also have the option of lightweight pullies, Fidanza flywheel, Eagle rods (weight loss for response)...the list goes on & on.

Let me know your budget & what you want from the car and I can help you.

Cheers

Dave