RB25 conversion parts list needed please!

[dave_harman1990]

I apologise for what is probably a previously asked question but i am starting to put together a potential list of parts that i would need for an RB25 conversion and would like peoples input, opinions and personal experience. I am aiming for about 380 to 420 bhp with as little lag as possible.

RB25DET Engine + gear box

wiring loom unless i can crimp the standard loom?

remapable ECU

new manifold (possibly top mount, followed by a custom downpipe if so)

Uprated clutch/ lightened flywheel suitable for 450bhp

Uprated engine and box mounts, any particular brand or will either sr or rb mounts fit the engine in place fine??

Either a t3 or t4 turbo, something that will spool up fairly quick but suitable for 450bhp and reliable

intercooler pipework for a front mount or is custom made best?

Best choice of front mount for the power, is an apex type 1 still ok for this or would people vote for greddy?

I've heard about with the prop's you need an RB front with an SR rear unless u buy a one peice aluminium one, whats recomended by everyone else?

Ive been told i need a new master cylinder for the clutch? any reason on this one please?

Is the uprated walbro fuel pump for the sr suitable for the rb or would that need upgrading again?

Is the standard RB head gasket suitable for this power or is it best replace this with another before fitting the engine? if so what thickness is best?

Ive been told the oil pumps can be known to fail so best to change this before dropping in the engine again.

what power will the standard injectors meet without being on max output?

Is it necessary to change the SR cross member to an RB one and if so what differences are there?

I've heard that the skyline diff has a much better ratio than the manual 14a for quicker spinning of the wheels, any light on which model of skyline, engine size, manual or auto, import or not etc etc please? this is one of the next mods id like to do so quite important please.

Anything else ive missed out??

I apologise if posting this annoys anyone but its something i've thought about before i bought the car and now its at the power where any mods i buy are only going to be SR suitable, i would rather make sure i am not throwing money awaw by forging an SR when i could be fitting a more trustworthy standard internal RB.

Any help on this would be amazing please people! thank you for looking
Dave

[danb]

RB25DET Engine + gear box

wiring loom unless i can crimp the standard loom? you usethe rb25 engine loom and patch into the 200sx int loom - there is a guide on here how to do it

remapable ECU

new manifold (possibly top mount, followed by a custom downpipe if so)

Uprated clutch/ lightened flywheel suitable for 450bhp

Uprated engine and box mounts, any particular brand or will either sr or rb mounts fit the engine in place fine?? use rb engine mounts on r33 cross member - drops more or less straight in

Either a t3 or t4 turbo, something that will spool up fairly quick but suitable for 450bhp and reliable - 3076 turbo will suit your needs - can fit stock manifold and low mount.

intercooler pipework for a front mount or is custom made best? front mount and you can adapt the pipework to fit.

Best choice of front mount for the power, is an apex type 1 still ok for this or would people vote for greddy? yes as above

I've heard about with the prop's you need an RB front with an SR rear unless u buy a one peice aluminium one, whats recomended by everyone else? use the rear SR one, mounted to the front part of the RB - the RB one will need shortening by around 5", a local prop shop will be able to reduce this and balance it for you.

Ive been told i need a new master cylinder for the clutch? any reason on this one please? im using the one from 200.

Is the uprated walbro fuel pump for the sr suitable for the rb or would that need upgrading again? leave the walbro from SR in

Is the standard RB head gasket suitable for this power or is it best replace this with another before fitting the engine? if so what thickness is best? for you power stock gasket will be fine

Ive been told the oil pumps can be known to fail so best to change this before dropping in the engine again. RB25 suffers from poor oil drainage, where oil stays in the head, if its just a daily driver then it will be fine, if your doing extensive drift/track work, then there is a good article on rb oil control on the net.

what power will the standard injectors meet without being on max output? around 330bhp - which is also the same limit as the rb maf - upgrade to z32 maf.

Is it necessary to change the SR cross member to an RB one and if so what differences are there? as stated aqbove, use r33 cross member and then you can use the rb mounts and it drops in.

I've heard that the skyline diff has a much better ratio than the manual 14a for quicker spinning of the wheels, any light on which model of skyline, engine size, manual or auto, import or not etc etc please? this is one of the next mods id like to do so quite important please. use 200 diff.

Anything else ive missed out??

[dave_harman1990]

thank you for the reply danb! bit more info on some please:

Which front mount intercooler would you recomend of the ones on the market, Apex, Greddy, or something else?

How much would i be looking at cutting and balancing the prop? is it worth the hassle over buying an already set up aluminium one?

What CC injectors would you recomend if i dont intend to up the power beyond 420 bhp?

With the z32 maf sensor is it easy enough to crimp into the wiring harness?

With the diff are you saying to keep my own or go with an automatic 14a diff? why would you not say the skyline diff also?

Was there anything additional i would need or does that sum it all up really?

And what is the reality cost in parts i would be looking at to do all of this?

Many Thanks again for the reply!

[danb]

Apex fmic will be fine for your needs

Prop cost me £75 to get shortened and balanced, new ally one your looking into £300+

Next step up frOm stock injectors are 550cc - they use same injectors as sr.

Z32 is doddle to fit plenty diagrams on skylineowners.com

Diff - I'm running a 2 way diff so not sure

Costs depends on how much work you do yourself

[jay20]

stick a r33 diff and shafts on it as its a much beter ratio. £75 sounds cheap for the prop i pay £140 still cheaper this way tho.id go for a 3071 tubby if your looking for 380-450bhp be less laggy.id change the headgasket whilst the engine is out much easyer,1.3 cosworth head gaskets. this is purley down to you and your cash flow but id get rid of the stock inlet and put a front facing plenum on means you dont have to cut the bottom webs of the bonnet to get it to shut. much neater and means much shorter pipes ether way its a bit of messing around with pipes.

[stevecrc]

If your after a good rb25 then check out my for sale thread as I have a complete RB with loom, ecu, coils ect ect. Came out of my mates car that was rotten. I drove it the night before we broke it, he drove my 200 hence why he broke it the next day lol

[dave_harman1990]

In reply to Danb, thank you for the more details! i need to try and price up the list and then work out my ways of gettin the money lol!!

In reply to stevecrc, i appreciate the offer but i may have found a whole car for 1500 if all goes to plan with 75000 miles.

In reply to Jay, im not sure if James Thring has said to you or not but im his mate (his girlfriends sisters boyfriend), and i was maybe going to get in touch with you about some of the work that id need doing. Plus i would KILL to see your 14a again, i saw it once on the drive at yours and almost curbed my motor where i couldnt take my eyes off it haha!! You have one hell of a car there mate! At some point i would like to come view ur lock up and check out ur brothers work in progress 15 too if thats ok?

New question, What is the situation with the full RB25 wiring loom, does it need to be crimped or if i get a stand alone ecu can the wiring be left as it is?

Cheers again for the replies people!

[danb]

New question, What is the situation with the full RB25 wiring loom, does it need to be crimped or if i get a stand alone ecu can the wiring be left as it is?

Cheers again for the replies people!

stand alone ecus ie will be car specific ie rb25, and soem are designed to be plug and play like the power fc so will need to have the rb loom

[dave_harman1990]

More questions people please:

Im after a top mount manifold for the RB and being honest one of the only places ive seen them is EBAY:

http://www.ebay.co.uk/itm/R33-NISSAN...item53eca86516

I realise its cheap so not going to be amazing but what is others peoples opinions? also, i realise it has a pipe on it for a wastegate, can these be blocked off as i have a HKS SSQV already that id like connected to my intercooler pipework or am i being stupid and these are to do with 2 different things?

Im also after an aluminium inlet mani and again ive seen one on ebay for 300 which looks identical to a Greddy but obviously again i realise its not going to be as good quality but again would this be ok for less than 400 horsepower? Just ive heard that the standard inlets can cause the 14a bonnet to not close due to the hight they sit.

where is the best place close to the kt16 postcode that people would recomend to get a custom made downpipe aswell as a couple of intercooler pipes, a turbo pipe for my induction and all for a good price?

Aswell as getting my RB front prop cut and balanced? And is exactly 5" that it needs cutting by?

Thank you again in advance people!!

[danb]

What turbo are you using?
The wastegate take off is for an external wastegate, nothing to do with blow off valves.
That manifold is rubbish, a few people on skyline owners have used them and cracked - I have found a place in new Zealand that trades on eBay and makes mild steel manifold, there's a long thread about them on the Aussie forums, anyway they work out at around £400 delivered, this manifold won't crack - that is if you are replacing the manifold.
As for the inlet manifold, yes depending what mOunting kit you use the inlet can catch the bonnet, the greddy copies on eBay seem be ok - alot on skyline owners use them.
As for the prop, it was 5" in my case, however when the engine and box are in just measure it before you get it shortened.

[dave_harman1990]

Atm im not sure what turbo ill be using, one of 3 depending on money but either a GT3071, GT3076 or a T3-04.

What external wastegate would you recomend sizewise and make please? And what is the situation with screamer pipes and how they attach to these please?

With the manifold this looks like what your saying, it looks well made anyway but from america its a bit of a risk without other opinions, which of these two is best for max flow:
http://www.ebay.co.uk/itm/Stainless-...item2a17835a8f

http://www.ebay.co.uk/itm/Nissan-RB2...item2c5e70b0fd

The inlet isnt a problem then i will purchase a Greddy copy thank you!

How is best to measure the props please, bolt the rb prop to the rear 14a prop then line them up between the gearbox and diff then mark it up somehow with where it needs to end?

NEW QUESTIONS:

Does the rb wiring loom connect straight up to the original 14a ODO or does it need crimping some how?

What are the best engine mounts to use for the swap, original R33 mounts or uprated solid ones, and if so where is best to purchase these from please?

[dave_harman1990]

Also, Apexperformance sell an Apex type 1 intercooler for an R33 aswell as an sx, Will either almost if not line up with the greddy inlet or do i need custom pipework made up for this?

And What is the best rad to fit for these conversions, uprated SR rad or uprated RB rad? any links for my questions would be amazing please!

[danb]

Atm im not sure what turbo ill be using, one of 3 depending on money but either a GT3071, GT3076 or a T3-04.

What external wastegate would you recomend sizewise and make please? And what is the situation with screamer pipes and how they attach to these please?

With the manifold this looks like what your saying, it looks well made anyway but from america its a bit of a risk without other opinions, which of these two is best for max flow:
http://www.ebay.co.uk/itm/Stainless-...item2a17835a8f

http://www.ebay.co.uk/itm/Nissan-RB2...item2c5e70b0fd

The inlet isnt a problem then i will purchase a Greddy copy thank you!

How is best to measure the props please, bolt the rb prop to the rear 14a prop then line them up between the gearbox and diff then mark it up somehow with where it needs to end?

NEW QUESTIONS:

Does the rb wiring loom connect straight up to the original 14a ODO or does it need crimping some how?

What are the best engine mounts to use for the swap, original R33 mounts or uprated solid ones, and if so where is best to purchase these from please?

Wastegate - go for a tial, depending on how big the turbo is, and whats the lowest amount of boost you want run determines the size of the wastegate. Larger the wastegate, ables to clear more gases, allowing lower boost control. You should be fine to run a 38mm gate at 0.6/0.8 on a 3071/76.

Screamer pipe is the pipe coming off the wastegate - leaving this to vent to atmosphere makes a lovely noise - of course track days and their noise limits become an issue, so some people plumb the screamer pipe back into the downpipe (exhaust place would make this up for you).

I dont like the design in the first one (CXracing), and the second one has better flow.

http://www.skylinesaustralia.com/for...heir-products/

There will be a groupby on skylineowners on these which i would recomend over and ebay stainless steel ones - will work out similar price too.

With the prop, once the engine and box are in the engine bay and bolted in, measure from the end of the box to the diff - simple as that

I do believe that the tacho will be slightly out from what it should read, but you can buy dakoto signal change thing, this will allow it to read correctly.

I have just used the stock r33 mounts - they were in good condition so no need to change them.

Also, Apexperformance sell an Apex type 1 intercooler for an R33 aswell as an sx, Will either almost if not line up with the greddy inlet or do i need custom pipework made up for this?

And What is the best rad to fit for these conversions, uprated SR rad or uprated RB rad? any links for my questions would be amazing please!

As you are going for a greddy inlet, get a fmic for the s14, you will just need to change the silicone hoses and a little bit of modding to get them onto the greddy inlet/turbo.

You need to use an S13 radiator, as the water inlet.outlets are on opposite sides on the SR rads. Im using a Koyo S13 radiator, but any decent uprated s13 radiator will do. I have used the r33 hoses without issue.

[dave_harman1990]

Wastegate - go for a tial, depending on how big the turbo is, and whats the lowest amount of boost you want run determines the size of the wastegate. Larger the wastegate, ables to clear more gases, allowing lower boost control. You should be fine to run a 38mm gate at 0.6/0.8 on a 3071/76.

If im intending to run a bar of boost would you say id need a bigger wastegate then?

With the prop, once the engine and box are in the engine bay and bolted in, measure from the end of the box to the diff - simple as that

This is actually a much better way to measure this, sorry for my retardedness haha!!

I do believe that the tacho will be slightly out from what it should read, but you can buy dakoto signal change thing, this will allow it to read correctly.

So the tacho may be out but with the plugs, would the same plugs be used behind the odo or since ill be using the RB wiring loom are the plugs different? sorry if this is a retarded question just obviously i havent got the skyline at all apart yet so not sure.

I have just used the stock r33 mounts - they were in good condition so no need to change them.

Did you need to modify these in anyway as ive read something about extending them or something :S ??

As you are going for a greddy inlet, get a fmic for the s14, you will just need to change the silicone hoses and a little bit of modding to get them onto the greddy inlet/turbo.

SO get the full kit for the 14a other than the hotpipe and then have it modified once its ready to be fitted, sounds like a good plan to me!

Thank you very much again for answering what was probably some very stupid questions! are you around the area again anytime soon mate id like to have a look at yours properly

[dave_harman1990]

Alllllllllso, with the s13 Koyo rad, do you need to buy a new uprated fan for this or keep the original? and what brand or link would you recomend for this pleeease?

[danb]

You should be ok with a 38mm wasegate.

No, get the engine and box in, measure the length from the back of the box to the diff - that tells you how long it needs to be, no scientific calculations required!

Im not too sure on the tacho, im sure it all connects just doesnt read correct due to different speed sensor - i wouldnt worry too much about this - just use a sat nav for speed until this is sorted.

the only mount that needs modifying is the gearbox one, a bracket needs to go from the existing bolt holes on the gearbox mount to the new ones - around 3-4" bracket - once its in, you will see its very easy!

I have fitted a koyo with my conversion, cut awayu the slam panel, and have mounted it with the viscous fan and also the cowling and mounted a slim line (ebay 12" fan) to the front of the radiator.