1JZ engine build +parts recommended

[celica77]

yeah no im aware of the diff upgrades etc. i run a complete modified hilux diff 3.7 lsd in my ra23. its a tad overkill for the power output of the 1ggte. but i find over kill is better than not enough and risking breakages. i will be putting the same difff into the ra28 its like a 8.5 inch 30 somthing spline unit from memory. strong as. and yea. the ra28 is getting the works. all the pannels have come off including outer rear panels for rust treatment. sill repair etc. it will have the engine bay in appropriate areas seam welded. run a compelete half rear roll cage. strut braces etc. modified tailshaft etc. and yep defs plan on running a R154 gearbox and exedy sports twin plate clutch. ive learnt alot with the 1ggte ra23. the 28 will be even better.
that stuff is all sussd. im just not familiar with the 1J motor so thats the real info im chasing along with the turbo selection.
by the end of it i truly feel i will be able to say ill own one of the very few truly rust repaired RA28 examples in the country. all spot welds removed. all panels off including rear panels down to bare shell and repaired.soda blasted. sand blasted. new sills etc. cage, all wheel disc brakes everything... with bog only being used to achieve body lines not fill holes HAHAHAHHA

JAK: yes ive heard about the ARP rod bolts. and yes defs will invest in some. still curious about the wastegate selection. 38mm or 50?

[jeffro ra28]

by the end of it i truly feel i will be able to say ill own one of the very few truly rust repaired RA28 examples in the country. all spot welds removed. all panels off including rear panels down to bare shell and repaired.soda blasted. sand blasted. new sills etc. cage, all wheel disc brakes everything... with bog only being used to achieve body lines not fill holes HAHAHAHHA

JAK: yes ive heard about the ARP rod bolts. and yes defs will invest in some. still curious about the wastegate selection. 38mm or 50?

LOL, my ra28 had no rust to start with, i have gotten inside the sill panels and all seams with mirrors and torches and still no rust, there are a few getting around, just not many

Yeah, Jak is in the money with the 2jz valves, a very worthy option if you are going to have the head off and doing some head work here and there.

Do not get mixed up with ARP2000 rod bolts and the standard type replacement rod bolts that ARP also offer.

A tial 44mm gate is also a worthy option, should one become available to you.

[Brendan-m2]

Hi mate, just thought I'd let you know on my experiences as thus far, I'm running a GT3582R with a Trust 50mm external gate running 23PSI. From what I have experienced I truly must admitt I find the wastegate struggles to hold open being so big (Wastegate is on softest spring setting), In my personal opinion I would go for the 38mm.

As for turbo selection I drive my car everyday and I couldn't be happier with the response from the GT35, it really is a great tutbo for a 1J (I start to see boost around 2500-3000 RPM).

On the note of cams, if you are going to go down the path of a GT35 I would strongly suggest getting a set of 264 Degree cams just to bring the best out of the turbo, if you decide to go for a GT30 I wouldn't bother.
In respects to the two turbos having driven 1J's with both I find the GT35 is a better choise as at the end of the day you arn't pushing as much boost for the same power.

As for injectors I'm using a set of HKS 540CC Injectors and they seem to suit my needs faily well, but for that added safety I would suggest going something along the lines of a 650CC injector, seeing as the cost is not really that much more.

And lastly what are you looking at in respects for fuel? I'm running a Walbro 255LPH and shortly I will being putting a Bosch 044 external in as well.

Anywho hope I was of some help

[jak]

yeah be careful as you can go to big on the cams. gas motorsport 2j was ran 6's with a gt55 and only 272's. There are alot of people that are using the 264/gt35/1j combo and seeing good results.

depends if you use a surge tank or fuel cell but a single 044 will handle that nicely. If using a standard tank a walbro will be ample for a primer.

Cheers
Jak

[celica77]

hey 264/gt35/1j combo with a 38mm gate seems to be the go so far. As it will offer more down the track also if i choose to persue more power. yeah ive always been a fan of aiding horsepower with boost. Id rather achieve the HP goal using less boost than purely relying on it. and yeah cheers guys all your help so far is much appreciated. turbo specs confuse the crap out of me.yeah fuel wise im thinking of running very similar to what i do on my 1ggte ra23. Pre pump to a 2L surge tank then with a 500HP + rating external highflow pump to the motor. i think i have a VL turbo one or some crap on my RA23. Although instead of 2 external pumps i might modify the existing RA28 tank to house a good internal pre pump to the surge tank.
with the injector option. is there a direct replacement 600cc+ for the 1JZ or is an aftermarket fuel rail with injectors in order? also whats the impedence on the 1JZ? that crap confuses me also.

[Brendan-m2]

yeah be careful as you can go to big on the cams. gas motorsport 2j was ran 6's with a gt55 and only 272's. There are alot of people that are using the 264/gt35/1j combo and seeing good results.

depends if you use a surge tank or fuel cell but a single 044 will handle that nicely. If using a standard tank a walbro will be ample for a primer.

Cheers
Jak

Sorry should have stated I will be putting a 2L surge tank in with the 044.
In regards to cams from what I have seen 264's are the perfect combo'd cam for a GT35 turbo, not to small and not to big but just right.

[1JZ.747]

interesting how every one says the 2j intake valves are bigger as brian crower lists them as the same size 1j and 2j and the valves i just ordered confirms that.

this thread is pretty on the mark with the suggestions, i ran a paul stanek 45mm when i had a to4r and it was great. boost control on the 6boost manifold, check with what kyles suggests, he does pretty good package prices

shane

[Brendan-m2]

hey 264/gt35/1j combo with a 38mm gate seems to be the go so far. As it will offer more down the track also if i choose to persue more power. yeah ive always been a fan of aiding horsepower with boost. Id rather achieve the HP goal using less boost than purely relying on it. and yeah cheers guys all your help so far is much appreciated. turbo specs confuse the crap out of me.yeah fuel wise im thinking of running very similar to what i do on my 1ggte ra23. Pre pump to a 2L surge tank then with a 500HP + rating external highflow pump to the motor. i think i have a VL turbo one or some crap on my RA23. Although instead of 2 external pumps i might modify the existing RA28 tank to house a good internal pre pump to the surge tank.
with the injector option. is there a direct replacement 600cc+ for the 1JZ or is an aftermarket fuel rail with injectors in order? also whats the impedence on the 1JZ? that crap confuses me also.

With injectors I have seen direct replacement 800cc injectors for 1J's so you should be able to find a 600cc injector to fit no problems. As for impedance if your going aftermarket computer I wouldn't worry about that to much as the computer will take care of it.

[jak]

I just compared the 1j and 2j valves as im using them in a 4a build.

these are just rough measurements.

1j ex 30mm
1j in 32mm

2j ex 29mm
2j in 33.5mm

You can only go 1mm oversize on 2j head but im not sure about the 1j. I will go and do some testing. The valve stems are the same length so that isnt an issue.

I dont know of any particular injectors off the top of my head, but i have seen plenty of direct replacement injectors for the 1j up around 600-800cc.

EDIT: 2j valves look like they will fit nicely in a 1j head, and the 2j inlet valve is definatly bigger than the 1j as it doesnt seat in the head.

Cheers
Jak

[jeffro ra28]

Jak, why only 1mm oversize on 2j head?

interesting how every one says the 2j intake valves are bigger as brian crower lists them as the same size 1j and 2j and the valves i just ordered confirms that.


shane

Hmm, Maybe BC made a boo boo, a few reliable sources have said that the 2j inlet valve is bigger then the 1jz. I can measure stock 1j valves, anyone got 2j valves lying around?


Oh and whilst we are on this topic. Has anyone got the .050" lift timing events of HKS cams?

They say 272, 264, 256 etc degree's duration, but do not specify at what lift duration this is.

Anyone ever doctored a set? Would be interesting for comparison purposes.

[jak]

Well i think u could get 1.5mm in there, but basically much over 1mm and it protrudes past the face of the cylinder head.

did some research and found on lexstreme that the 2j inlet valves are 33.6mm across the face.

the 1j does have the bigger exhaust valve tho.

Cheers
Jak

[jeffro ra28]

So long as the valve does not go beyond the diameter of the fire ring of the head then its not a problem.
Valve seats can always be sunk deeper.

The only things limiting the physical size of larger valves is when the valves connects with its partner or the opposing valve when on TDC overlap (intake valve connect with exhaust valve) or the cylinder bore.
Not that im saying the biggest valve is best just that i find it hard to believe that a 2jz chamber will only accept up to 1.5mm oversize valves.

[celica77]

ahh ok yep sweet dont think ill go an aftermarket fuel rail then if i can get direct replacement injectors. yea i defs will run an ECU. what have ppl found to be good on the 1J? i have wolf v500 on my 1ggte. i dont think its the best though. still have massive cold start issues and its seen ages on a dyno and still i feel is rich. anyways.
so will the HKS 264 degree cams 9mm lift intake and exhaust cams fit in the 1J head without other mods needed? ill run adjustable cam gears to to try move the curve to where id like it more suited to the street. yea i will talk to kyle when i get closer to doing this. i had one of his manifolds for my 1ggte. but decided to scrap the single turbo idea on the 1ggte. he is extremly helpful. yeah ill ask his opinion on the external gate....
i dont think ill bother with the 2J valves. i might just get the head acid cleaned. and not bother with the porting.

[jeffro ra28]

It as advisable that you upgrade the valve springs for use with 264 cams. that is pretty much it.

[Smokey228]

Hey man, just found this thread now...

I made 400whp with a stock 1j, stopped tuning cause i ran out of map.

But if you go some cams and some headwork, you'll make the same power and it will just drive alot better... (this is what i'll probably do next or if a hg goes)

But for wastegate, and spring choice, you want to be able to control boost with gate rather then bleed valve, so if you want to run 17psi (like me), then run a 17psi spring (like me, who is yet to see and downfalls or bad spikes)...

Also, the 6boost mani is fark off effcient, and alot of ppl say run the biggest gate you have room for. There is no downsize in having a oversize gate, its only going to help boost control, so if you can go a progate 50mm or a tial 44mm, as they are both well sized and compact in design. Avoid the china spec ones, as even the 38mm ones are retarded big

If you upgrade cams, upgrade springs and ensure your valves are all good and the clearances if your going to port or flow your head a well matched, it'd be fail to go to all that trouble and take a short cut there...

Bottom end i wouldnt bother touching, hypo77 made 580hp (on the grape vine) despite the belief of 520hp with stock bottom end and just cams and gears + 3540 with 1.06 rear... Also running lots of boost... It blew, but i think it was either failed rings, or it munched a valve...

It was an unopened wrecker motor though, so thats still a big claim!

Cheers,
Jase