Jump to content
SAU Community

Recommended Posts

Hey,

A mate of a mate of mine offered me a cheap port and pollish for my R34 GTT yesterday and was wondering if i should go ahead with it or not.

I have some understanding of what is involved but i just wanted to get more info before i do anything about it.

What are the pros and cons of doing it and has anyone else done it to there GTT?

Is there a noticeable power gain and saving on economy?

He said he will do it for $50 / cylinder = $300 plus the cost of getting the head re-done and it will take about 2 days... is that a decent price?

Would people recommend it, and if not, why?

Any comments are greatly appreciated!

Thanks.

Link to comment
https://www.sau.com.au/forums/topic/130142-port-and-pollish-on-r34-gtt/
Share on other sites

What do you mean the "head re-done" and how much for that? Last time I checked that part of it would cost $500-600 making the total $900ish which is still cheapish but do you need it? We need more info on your setup to answer that question.

yeh its worth it...if your engine is already pulled out and apart and your doing other mods to it. But just for the sake of pulling your std motor apart and getting the head port n polished and then faced with a maybe on the valves if thats what hes referring to for the 'head redone' then its prob not worth the hassle for the money even if it is cheap.

Hey,

Thanks for the replies guys!

Yeah, i am using the stock turbo right now with no plans to upgrade it till it dies...

I still have stock ECU, injectors, fuel pump etc...

My current performance mods are:

- Air pod

- Exhaust

- 600mm FMIC using stock piping

I think he meant getting the head machined or something, and he mentioned something about the lifters too...

The car only has 56,000kms and hasnt been flogged from what i can tell, so the engine still should be in very decent condition... He recommends getting it done as it is a decent price and gives you more power etc... but if its gonna cost another $500 - $600 for the head, i think i'll leave it.

Next time i see him ill ask what exactly needs to be done to it, coz he said he has to get that done by someone else as he doesnt have the equipment to do it... i thought he said its around $150 though? I'll have to double check.

Thanks all.

I think he meant getting the head machined or something, and he mentioned something about the lifters too...

I'm probably way off the mark here.. but isn't the idea of machining your head to increase compression? Don't you want to decrease it?

Tell me if i'm wrong guys.

Depends which part of the head you machine.

Another couple of costs you seem to have forgotten about are a new head gasket and labour.

Also with stock everything there is absolutely no point whatsoever in doing this mod.

DON'T DO IT.

I say otherwise; DO IT :P

Change the head gasket; change the valve springs; camshafts; valves... replace head studs; do the port and polish and end up with a race-prepped head!

Sure you might live in a cardboard box after; but you know it ain't stock no more!!!

I say otherwise; DO IT :P

Change the head gasket; change the valve springs; camshafts; valves... replace head studs; do the port and polish and end up with a race-prepped head!

Sure you might live in a cardboard box after; but you know it ain't stock no more!!!

Ignore this person. He is an ass.

waste of time for your set-up. $1000 could be spend elsewhere for much better gains.

Agreed

Far better bang for buck mods witrh your setup.

I could think of around 8 grand you can spend elsewhere before even coming close to needing porting

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • For once a good news  It needed to be adjusted by that one nut and it is ok  At least something was easy But thank you very much for help. But a small issue is now(gearbox) that when the car is stationary you can hear "clinking" from gearbox so some of the bearing is 100% not that happy... It goes away once you push clutch so it is 100% gearbox. Just if you know...what that bearing could be? It sounding like "spun bearing" but it is louder.
    • Yeah, that's fine**. But the numbers you came up with are just wrong. Try it for yourself. Put in any voltage from the possible range and see what result you get. You get nonsense. ** When I say "fine", I mean, it's still shit. The very simple linear formula (slope & intercept) is shit for a sensor with a non-linear response. This is the curve, from your data above. Look at the CURVE! It's only really linear between about 30 and 90 °C. And if you used only that range to define a curve, it would be great. But you would go more and more wrong as you went to higher temps. And that is why the slope & intercept found when you use 50 and 150 as the end points is so bad halfway between those points. The real curve is a long way below the linear curve which just zips straight between the end points, like this one. You could probably use the same slope and a lower intercept, to move that straight line down, and spread the error out. But you would 5-10°C off in a lot of places. You'd need to say what temperature range you really wanted to be most right - say, 100 to 130, and plop the line closest to teh real curve in that region, which would make it quite wrong down at the lower temperatures. Let me just say that HPTuners are not being realistic in only allowing for a simple linear curve. 
    • I feel I should re-iterate. The above picture is the only option available in the software and the blurb from HP Tuners I quoted earlier is the only way to add data to it and that's the description they offer as to how to figure it out. The only fields available is the blank box after (Input/ ) and the box right before = Output. Those are the only numbers that can be entered.
    • No, your formula is arse backwards. Mine is totally different to yours, and is the one I said was bang on at 50 and 150. I'll put your data into Excel (actually it already is, chart it and fit a linear fit to it, aiming to make it evenly wrong across the whole span. But not now. Other things to do first.
    • God damnit. The only option I actually have in the software is the one that is screenshotted. I am glad that I at least got it right... for those two points. Would it actually change anything if I chose/used 80C and 120C as the two points instead? My brain wants to imagine the formula put into HPtuners would be the same equation, otherwise none of this makes sense to me, unless: 1) The formula you put into VCM Scanner/HPTuners is always linear 2) The two points/input pairs are only arbitrary to choose (as the documentation implies) IF the actual scaling of the sensor is linear. then 3) If the scaling is not linear, the two points you choose matter a great deal, because the formula will draw a line between those two points only.
×
×
  • Create New...