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Discussion Starter · #1 ·
Hey Guys & Gals

I'm thinking its time to start rebuilding my RB. I've been reading through a lot of the rebuild threads looking at the shiny parts everybody else fits and I've compiled a spec list, but I think I may have gone waaaayyyy over the top.

I am after a car I can drive every day to work (A & B roads, some traffic), weekend use, very occasional track (maybe 1-2 times per year, don't know yet never been on track). My driving style is a little conservative, sometimes I just drive nice and easy and hardly come on boost, other days I may feel a little more spirited. Some days I have to follow a tractor, other days the roads will be clear.

Not looking for big hp, but maybe a little more than current. I would like to get a nice responsive build, especially at the lower rpms which would (for example) help 30-40mph accel.

The biggest dilemma I face is whether to get forged pistons. I know they are stonger, lighter, run more hp etc... but I also know they are for "race" use and when run cold will slap the cylinder walls and shatter the rings. They are also expensive.

If I was to go for forged pistons I guess I would be better off with a 2.8 stroker? I'm guessing that this (with mods listed below) net me to about 600-650hp. Can/do people run this every day in traffic etc, or is this spec more for weekend/occasional use?

I don't mind the rattle when cold as long as it isn't going to damage anything. I'm not a mechanic but as far as I see it noise = vibration = damage. I guess forged also use a lot more oil? Again not a problem if no damage will be caused. What does it take to get these to operating temperature? Do I just drive easy until the oil temp comes up same as I do now?

What are forged pistons/stroker kits like to live with on a daily basis is the main question I guess?

If I don't use forged pistons, what are the Nismo N1 pistons like? Stronger than stock, but not as strong as forged? Stock reliability.

Anyway, this is my current spec list as it is at the moment:

HKS Super Racing Intakes
HKS Mild Steel Downpipes
Sports cat
Veilside Titanium "Teardrop" exhaust
Baffled Twin Turbo Pipe
HKS 1/2 Hard Pipe Kit
HKS R-Type Intercooler
Tein Monoflex Coilovers
Nismo front strut brace w/ brake cylinder stopper
Nismo brake lines
DS2500 Pads front / std rear
DBA Discs all round
Panasport racing alloys (275 all round)
Greddy Profec B spec II boost controller
Greddy Aluminium radiator
Unknown clutch (will find out when the engine is removed)
Cusco Hicas delete kit
Cusco Front camber arms
Exhaust temp gauge

With the exception of the engine internals covered above, this is a list of other parts to be fitted during the rebuild.

Balance existing crank with std rods and N1 pistons
ATI Crank Damper Pulley Kit
Nismo Gasket Set
Tomei High Flow Oil Pump
Tomei Sump Baffle Plate
Tomei Oil Gallery Restrictor
Tomei Oil Line Restrictor
Sump extension (can these be got without lowering ground clearance)
Nismo N1 Water Pump
Tomei Poncam Camshafts
Adjustable Pulley
Kevlar cam belt
SplitFire Direct Ignition Coil Packs
Tomei Turbine Outlet Pipes
HKS GT-SS Turbo Upgrade
High flow fuel pump
Injectors (don't know what capacity)
Adjustable Fuel Regulator?
APEXi Power FC D-Jetro
Oil catch tank

I know I need other little bits n bobs like head bolts, bearings etc... but is there anything big I have missed or should upgrade as well? Anything else while the engine is out?

If I am forking out for a stroker kit (or even forged pistons/rods) then I will probably leave the GT-SS for a later date. Is a turbo upgrade an engine out job? This will effect my decision.

Abbey Motorsport will be doing all the work so the final list will be down to them. I'm just trying to get a clearer picture of what I need/want so I can let Mark know.

What would the mpg be like with this kind of setup? Currently doing about 20-23mpg (370-400km to a tank) which perfectly fine, I can (and do) live with this. I don't really want something that only does 8 to the gallon or anything silly like that.


Thank you for any and all help and guidance you can give me. This is a one time only job and I really want to get it right first time.

Many thanks

Tim
 

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personally think about it this way, you only want the engine to come out once so do the forged upgrade whilst you can!

i was in the same situation as you and it took me a while to decide but my tuner was definately with me when it came to running forged pistons and i found the extra money just took longer for the build!

I am running a pretty much idential setup to you with forged pistons and fully balanced bottom end etc.

Piston slap is a minor thing to worry about, it totally depends how well the bore is machined for the pistons and rings and what pistons used etc. Abbey will have no problem in doing a first class engine for you!

Id think about a head drain or something like that as well, the tomei pumps can pump an aweful amount of oil around and you want it returning to the sump as quickly as possible! Most of the time isnt a problem but is nice to be safer than sorry!

A FPR wont really be necessary unless you want to up the fuel pressure which you probably wont do for street use. Also look at about 720/740cc injectors sizewise for the spec.

I didnt upgrade to forged rods as tbh i dont see the need unless running silly high spec! How many people have put a rod through the block because of the power put through them! Im running about 550 with no problem and havent heard of any stories of rod failure at higher bhp.
 

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Discussion Starter · #5 ·
Thanks G40tee

740cc injectors!!!! That sounds like a very low mpg :(

The spec I have at the moment is 330awhp with the standard twin turbo pipe, standard intercooler pipes and standard intercooler. I guess this is around 420-430 hp at the fly with the intercooler etc? I'm still on the standard injectors (444cc?) so surely they must be running at a v.high duty cycle at the moment??? Guess this is one of those things Abbey will sort out in due time.

Thanks
Tim
 

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its all in the mapping my friend! :) but yeah your standard injectors could be very close to their peak efficiency. Mine run at tops 72% (of 85%) of the injectors duty. Rob seems to have done a good job on the mapping, doesnt run his cars too rich unless its needed it seems! GTSS turbos will give you oki-ish economy but instant response when pressing the loud pedal! I know i have them! haha If you want better economy bigger turbos will give you that due to being able to drive off boost more but then you lose the streetability of it.

i get tops about 20mpg i reckon but i dont think im brilliant at driving economically.

id reckon on getting a bigger intercooler as well, alot of people on here will say not a necessity but it will help in the power stakes!
 

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to my understanding, as power goes up, the first weakness of a stock RB (around 500-550hp) shows up in the conrod bolts and pistons. forged pistons are cheaper rather than buying oem from the dealer anyway. no point in going back to stock.

theres 2 types of metals used in forged pistons. one of them is harder (and stronger) than the other, which also requires bigger bore to piston clearance (which is what causes piston slap when cold). both of them are stronger than stock.

i'm not sure whether any of the respectable companies make the forged pistons from the softer material mentioned before, but if you pick out a piston that comes from the "big players" and has low piston to bore clearance i suppose you'll be fine when it comes to piston slap.

as for the stroker kit, its not worth buying any jap kits . they cost anywhere between 3-5k, when a brand new forged bottom end using a new stock crank will run you 1700ish?.

if you can find a tuner that can spec you a stroker crank from Farndon (company in coventry that makes the cranks HKS uses in their strokers) along with the appropriate rods and piston from their supplier, that'd be the best value. the crank is 800quid more expensive than a new stock one. pistons should be the same but conrods need to be a bit shorter i think, no reason to be more expensive tho. dont have much info on this, if you get a quote from a tuner i'd be very interested to hear their proposals :)

as for injectors, these babies have reported better idle and general operation than 600ccs even tho they're 1000.
older technology injectors are like faucets lol.

Injector Dynamics 1000cc Bosch injector

oh and last thing, if you're worried/dont like rattles and noises, i'd carefuly pick out cams and clutch/flywheel combo. anything over 260 degrees and some clutch/flywheel combos make your car sound like a broken down diesel:)

i dont have any real life experience from what's mentioned above (except from lw flywheel (*&%^$(^@$^) , just my own research.


good luck
 

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oh and, extended sumps usually become the lowest point of the car. not good for a daily driver i suppose. i'd hate to plant my sump on a speed bump haha

just baffles are fine for the street, and if you're paranoid an accusump would be nice for pre oiling the engine before startup and in the event of starvation (highly unlikely on the street). oil returns from the head to the block are really popular in the aussie forums, dont know how well they work tho.
 

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Discussion Starter · #9 ·
Thanks for all the info guys!

Deffo going to look into these accusumps, but I will need a sump extension if I'm running a Tomei pump.

I understand about there not being much point in putting in near standard pistons, and that forged makes more sense, but I'm just a little worried that I won't be able to use my car every day because on the bottom line they are for "race use". How long does it take them to expand properly and to not slap around? Are we talking about the length of time as oil or do I have to cane it everywhere to keep them hot?

I guess the polynickelmolybedaniumite coated pistons are better / harder wearing than those without the coating (looking at hks here). Does the block need to be sleeved with these or just a re-hone?

Half of me just wants to go to Abbey MS, give them a budget and what I want out of it and let them get on with it. The other half wants to look at all the available options, make informed decisions and understand why each and every part has been used. I'm sure the guys at Abbey can tell me why they use what they use, but it isn't the same as working it out for myself. Plus I'm learning alot as well ;)

Cheers for all the help

Tim

:)
 

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an extended sump is not necessary for a bigger oil pump. you just need to restrict the oil going to the head so that the bottom doesnt run dry. this is achieved by fitting a restrictor in the block so that the increased oil flow doesnt overfill the head, others machine the oil return gallerys while the engine is apart for a full rebuild, and others fit an external oil return pipe running from the back of the head down to the sump. (or all of the above haha)

piston slap is only there for the first couple minutes after a cold start, till the piston expands a bit and fills the gap. many rbs with forged pistons dont even have it at all. its a hit or miss really.

i would indeed present abbey with a budget and take it from there :)

dont forget to ask if they can spec you an in house 2.8 stroker. im interested in the price difference between that and a new std crank +forged pistons/rods route everyone seems to take.
 
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