Rebuild advise

[Guest KILLER-T]

I got all my quotes now for my rebuild and there is alot of item's on the quotes that i had never thaught about and some things i have never heard of. What i want to know is if all the things in the list below are needed for a motor that will be putting out around 340rwhp

Forged pistons

Nissan bearings and gasket set (do i need to use genuine nissan ones or is there a cheeper after market set)

Resize connecting rods

Magnaflux connecting rods

polish connecting rods

Shotpeening connecting rods

Magnaflux crankshaft

Re-grinding crankshaft

chamfering oil holes at crankshaft ?

Fully balance engine internals

Plug oil holes

Rebore and honing engine block

Decking block

HKS metal head gasket

the only reason i am asking is because this rebuild is getting damm expensive

[Guest GregGTR]

Killer-T,

All the engine mods that you have listed will only marginally improve your HP, BUT it will make you engine last longer, (not a one hit wonder), remember you are talking about 250RWKW, (~330FWKW) that is more than double the factory power. In my experience, once you start going for those HP figures you will start breaking things left and right, and if the price of the upgrade is too expensive, ummm your yearly maintenance will also be close to the same figure. I would recommend selling your T and going for a R (GTR) this way at least you will have a stronger base to start with and you will be able to take advantage of the 4WD traction.

G>

[51jay]

""Nissan bearings and gasket set (do i need to use genuine nissan ones or is there a cheeper after market set ""

You'r spending that much money !! looking for that much output!! and you'r looking for a cheap gasket set!!!!

you'r an idiot

[Guest DAZSPC]

Yes, what GregGTR said.

Buidling a solid engine internally will promote longevity and would also enable you to use more serious bolt ons without so much risk of the engine making like a hand grenade.

As far as Chamfering goes I think this is right.

If you imagine your crank as a round steel rod, then imagine getting a drill and drilling a hole through that rod at 90 degrees for oil to flow through, you have a stock setup. (figuratively speaking). imagine looking at the surface of the crank where the hole is, then using say, a couple of sizes larger drill to just slightly flare, countersink, widen (use whatever word u like) the top of the hole, this is what I think Chamfering is, it allows more consistent oil flow over your big end bearings, which at high RPM and/or effective compression (highRPM + high Boost) is a very, very, good thing.

As for shotpeening and magnafluxing and polishing, i believe all that is essentially to remove any weak spots on moving parts. any burs or casting seams or irregularities in the structure on a con rod or crank (or cam for that matter) are potential weak points.

Please correct me if I am wrong though, I'm not a mechanic or anything, just built a few engines a few years ago.

[Guest KILLER-T]

Originally posted by jay51

""Nissan bearings and gasket set (do i need to use genuine nissan ones or is there a cheeper after market set ""

  You'r spending that much money !!   looking for that much output!!  and you'r looking for  a cheap gasket set!!!!

  you'r an idiot

WTF why am i a idiot i was quoted $1500 for a set of gaskets and bearings i thaught that was a bit rich It's F U C K E N posts like yours that make new forums hard to get off the ground.I mean were do you get off calling someone a idiot for trying to save a bit of $$$ doing a rebuild you are the IDIOT :shake: :shake:

[Guest KILLER-T]

Now i have that off my chest i would like to thank all the other replys to my post all advice is greatly appreciated i dont realy want any more power 340rwhp is enough all i want to do is make it a bit stronger so it will last i have already spent lots of cash on my car eg. power fc ,AVC-R, big cooler ,bigger turbo injectors and fuel pump so i guess i will have to spend a bit more on this rebuild but im sure it will be worth it

[rev210]

From what I hear the RB25 bottom end is very strong. I would also 'ring around' to get a good price on the machine work (i'm sure you are doing that just remember that V8 performance shops are equally good at doing this and as far as price goes you should start shopping there first). Chris Mills , Geoff kendrick etc. just give them a list of what sort of machining you want with the rebuild and sound like you know it all, you are less likely to pay through the nose.

It is also important to 'clearance' the bearings for the additional horspower and revs. Factory clearances could mean an nice bottom end lets go when you start reving beyond factory redlines. If they aren't advising you on this along with camfering etc. then really whats the point? Also balancing the crankshaft assembly is a must do on such an engine.

As I mentioned on SDU, the heads are also worth a hard look to see if enlarging valves, beefing up springs/retainers etc will be worth while.

[Guest KILLER-T]

Hey can you read minds or something because i was driving down leach hwy today and saw criss mills so i gave him a call and his quote is like half of what other shops have quoted:)

[rev210]

Originally posted by KILLER-T

Hey can you read minds or something because i was driving down leach hwy today and saw criss mills so i gave him a call and his quote is like half of what other shops have quoted:)

Good work dude!

When it comes to engine builds give all your traditional high performance jap tuning places a big miss, they don't build half as many engines as these guys. Sure they do V8s alot but don't think for a second that a V8 requires less precision work than our RB's. They do engine machining in their sleep!

Make sure you get some quotes on the head work too.

Have fun spending:D

[51jay]

KILLER-T hmmmmm...... perhaps I was a little harsh, I apologise.

rev210 has given good advice, i'll give you a warning.

There are an awfull lot of shonky people out there, some of them with quite reputable names( from personal expearience ,this goes for the V8 mob too) the time to find out about them is befor you start.

From your post you don't know too much about what you'r doing.... that was a short list you posted yet a lot you hadn't thought about and some you'd never heared of. You should be doing a lot more research and reading.

You try to double the factory output you can end up with a s**t hot Skyline thats a pleasure to drive or an expensive malingering mongrel that's a pain in the a**e to own. I along with everyone on these forums would like you to have the former.

To get this you need to put the effort in before you start.

If you don't ......you'r an idiot.

[Cubes]

When I was looking in to a RB30DET rebuild I was quoted the following to handle up to 250rwkw reliably.

Custom Forged Pistons (9:1 CR)

Crack test rods I think he said

Fully Balanced

O-ringed block

Std Nissan rb30 head gasket

Rb25de head with the slag etc cleaned up, can't remember the terminology he used but it is basically a mild port job.

He also said the cams in the NA rb25de head are better than the T head, btw the t head is a pain as it has VCT.

He also said that 250rwkw would be around the 7000rpm mark.

Heaps grunty down low with improved fuel economy over the rb20det as it has more torque and doesn't require you to use the turbo at every set of lights.

I'll have to find his name and number.

He was recommended by Adelaide Turbo Tune, which is the brother of ATS, Adelaide Turbo Services that has been in several articles in zoom etc.

[rev210]

Originally posted by -Joel-

When I was looking in to a RB30DET rebuild I was quoted the following to handle up to 250rwkw reliably.

Custom Forged Pistons (9:1 CR)

Crack test rods I think he said

Fully Balanced

O-ringed block

Std Nissan rb30 head gasket

Rb25de head with the slag etc cleaned up, can't remember the terminology he used but it is basically a mild port job.

He also said the cams in the NA rb25de head are better than the T head, btw the t head is a pain as it has VCT.

He also said that 250rwkw would be around the 7000rpm mark.

Heaps grunty down low with improved fuel economy over the rb20det as it has more torque and doesn't require you to use the turbo at every set of lights.

I'll have to find his name and number.

He was recommended by Adelaide Turbo Tune, which is the brother of ATS, Adelaide Turbo Services that has been in several articles in zoom etc.

Weird,

The NA heads I would imagine do not have the strength(springs etc) or valve size/combustion camber of the turbo head. The VCT is not realy a pain if you get the right grind of cam and an aftermarket ecu.

[Cubes]

Quote:

Weird,

The NA heads I would imagine do not have the strength(springs etc) or valve size/combustion camber of the turbo head. The VCT is not realy a pain if you get the right grind of cam and an aftermarket ecu.

-------

Apparently the head is the same as a T head no difference and also he does change the valve springs.

The problem with the aftermarket ecu is that it taks on another couple of grand, if you were after every little bit of power then sure it would be worth to pay the extra for the vct heads and also the ecu.

But I was just after 250rwkw streeter, lots of low and mid range..

BUT... Its costs to much.. I will be happy with 200rwkw anyhow... 250rwkw comes later.. later in a gtr..

Around 4 years down the track me thinx.

[matlowth]

Killer-T,

One thing I've learnt (after doing a performance engine rebuild recently), is that the price they quote you is always much less than what it ends up costing.

No fault of the workshop however, it's just that you always end up with lots of little things that make your bill much more.

In addition to that, a performance rebuild always takes lots longer than you'd expect it to. Waiting on my forged pistons alone took me 3 months! Once again, not anyones fault, it's just (at the time of the order), all the race teams had already put in their order for a seasons worth of Forged Pistons. You can imagine who got priority

Oh - and save your $$$ on the nissan gasket kit. The only gasket my car uses is for the head, and that's a Tomei 1.2mm Metal Head gasket.

matt

[Guest KILLER-T]

The rebuild is going good sofar Chris mills has all the parts for my car exept the pistons they are coming next week and has stripped the motor. I went down for a look and picked up my stuffed piston its missing half of the ringland:eek: it will make a good ashtray:uh-huh: I decided to spend a bit more and get a mild port and polish and the head serviced i'm also getting the rocker cover and intake manifold polished so it will look wicked once its all put back together :burnout: :burnout:

[GraemeWi]

I was having a look at a 25T head today and I was really impressed by the standard of the inlet ports - other than a few small casting marks which could be polished out, it was really good for a production head.

A couple of years ago I had an engine rebuild where I asked for chamfering the oil holes in the crankshaft. I recon it was a good move and helped feed oil to the bearings especially on startup.

Would you be able to get any before and after pictures of the head work? It would be interesting to see for sure.

Cheers,

GW