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R32 Build Ideas


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Hi guys first post and a big one at that, this will most likely be a question you have heard too many times but I'm looking for some input on a 1991 R32 Gtst build.

As of now I am stuck between a few options and layouts. The main one being the biggest ticket item, the engine. While the RB20DET currently sitting pretty between the towers is doing its job its lacking what I want from it.

Im not looking for a 1000hp daily driver that is cheap to build and comes on boost at 3 grand (something I'm sure your asked about every so often)

Im chasing around 300hp ATW, enough to have a nicely fast street car, that I can drive around on a daily affair and not have to worrie and when/what its going to break next.

Cost isnt a huge issue but as with everything it is always in my mind. I've been searching around for engines and prices just to get a feel for what I could do.

But in the end I need more input from some Skyline experts.

So for around 300 safe rwhp what would I be looking at doing and what sould I expect to spend? I'm happy to do away with the humble RB20 if need be.

Thanks in advance

David

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So for 300rwhp the RB20 would be ample enough and not crap itself? Im planning on building to last...hense the average HP figure. Ive been shopping around for parts for both the RB25 and the RB20, so far oddly enough RB20 parts cost more but then again a RB25 shoehorned in sort of evens it out.

Thanks for the reply.

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no need for a rb25 conversion. If you do one, dont expect to be running it with the rb20 gearbox. So factor in another $1500 for the gearbox.

RB20 + HKS2530 or HKS2530 ($1200~) will get you 220-230kw with all supporting mods. Full boost comes in on a 2530 at about 3800rpm.

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Yeah I know the standard 20 box wouldnt take it. Any information on the new 30 series turbos when matted up to a RB20? A friend of mine has been preaching them like they are the new sliced bread.

End goal is too keep it as responsive as possible, and while I know more HP = more lag I would love to keep it to a minimum.

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bleh do GTS-4's have gtr gearboxes in them ? i was changing my bottom shifter bush and i was directed by just jap to the GTR ones... fitted perfect.. but the question is... RB25 in my gts-4 do i need to change the box?

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Well lets say 1/4 mile time, Already have the power to the ground sorted as well as handling upgrades...found a Set of Tein Super Streets for $1400, Tein <3

lol suspension modifications dont stop at buying some coilovers. pineapples, caster, camber bushes and swaybars still to go.

Do some reading here; http://www.skylinesaustralia.com/forums/Rb...no-t103095.html

I think you also need to think about what exactly you are after. Why did you mention 300hp for? If you are interested in 1/4 times, then you should first choose a time you are after and then work out how much power you would need to have to gain that. 1/4 mile comes down to driver skill in the end. If all you do is wheel spin and/or bog down from the line, you will always get a shit time.

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Pineapples, caster, camber bushes and swaybars are a given, just the coil overs being a bigger ticket item is why I said anything about them. As for the RB20 turbo thread ive been reading through all of the pages getting an idea on what sort of mods make what sort of power along with things like injector sizes and fuel pumps.

300hp is just a number, its a decent amount over standard but not too much that its getting into needing complete forging. Plus with what I have seen as far as big numbers from RB20's I've been hard pressed finding many past 400hp. Most are about 300 so im guessing thats a safe number to have coming from them.

I am somewhat interested in 1/4 mile times, but mainly to find out what sort of times they pull with that kind of power, bit of a long story with a drag coming up between a few mates in a few years time, loser must buy a van...I dont like vans.

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Don't be too concerned with the RB20DET gearbox, mine has been holding up find for the last couple of years with 250 rwkw. Might be a bit different if I was launching it on slicks down a track though.

For 300hp stick with the RB20, in standard form it's a tough little motor, and tends to handle more abuse than the RB25.

I've put a RB25 in mine, and the car goes bloody well, but if I was to do it all again, I would go with the RB26. Much easier conversion (wiring wise) than the RB25, and a better starting point when you want to chase more power down the track.

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Well I think I fit the bill here...

I had an RB20 with HKS 2530, making just shy of 200rwkw so about 270hp not as much as you want but close...

I ended up going for an RB25 for 2 reasons, 1 I managed to find a complete running R33 for the conversion and 2 I didnt want to spend $$$ on rebuilding an RB20 or buying parts that wouldn't be of use in the future i.e. injectors Power FC etc

The conversion wasn't too troublesome, and the car drives exactly the same now, handling and feel wise. It's just that now even off boost the car makes great power and is much more steetable and requires bugger all revs to keep up with traffic and there is more power everywhere - with a stock rb25 (except the 2530).

Depends on what you want, I got tired of having to wait for the 20 to spool up everytime I changed gears below 5,000rpm. It made power delivery very crappy when going from 2nd to 3rd when you didnt want to hit 130kmph!

I would see if you can get a ride in a couple of RB20's making that kind of power - should be pretty easy as most of them are up around 200kw. Then go for a drive in a RB25 powered one, you'll see what I mean.

My mind was made up when I went for a spin in an RB30 powered 32... Different ball game! I went the 25 as I can make it legal

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I am leaning towards keeping the RB20 purely based on im not looking for huge power and the only times I would really be needing it would be stuffing about on track or drift days. I don't mind about the lack of real power on the street as I am more than happy with sticking to the speed limit and not giving my license to a cop. Also waiting for spool isnt really a problem now as being the standard turbo it comes on at nothing, but once the new turbo finds it way home I doubt I will really mind, not into going fast on the street anymore. been there done that got the ticket. Just like driving my piece of history.

I've been in a R33 pushing around 240kw and was pleased with how quick the power came on, but Im yet to find a RB20 of the same sort of power.

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my feelings are that the spirit of the car is contained inside the original engine.. so keep the 20. the 20 may lack low down power... but who cares... you want low down?? get a commodore.. 4k to 8k is where its at and thats what the 20 will love to do..

as Ash as said... define fast??

do you want to use 100% of 150kw??

or use 30% of 500kw??

also... real "fast" around a track is felt in the corners... i rode in a v8 supercar not long ago.. and sure the straight line speed and out of corner punch were fun... but not much more to a mildly modified evo... but the g forces experienced under braking and around the corners were phenomenal!!

its easier and much more fun to drive a slow car to the limit... than to have to hold back in a more powerful car.

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my feelings are that the spirit of the car is contained inside the original engine.. so keep the 20. the 20 may lack low down power... but who cares... you want low down?? get a commodore.. 4k to 8k is where its at and thats what the 20 will love to do..

Could never in my life own a Commodore, the R32 Gtst was the first car I ever bought and will be the last car I ever own.

I would not even notice giving up 1000rpm to lag as it starts pulling hard from about 2300 with the current standard turbo, and as you said, 4 grand to the limit is where the fun starts. I would rather the car have more than what I will be using just not to really stress any part of the chain of parts, so say if my final power figure is 300hp I want the parts capable of doing 350hp, just so everything isnt stressed or running at its limits.

I'm not chasing punch in the face power when I put my foot down but more of a user friendly power curve. I would love to go the Mines route of builds i.e not excessive power but the tune and the general setup and and parts used make for a very quick responsive ride.

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