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1jz Vs Rb25 An Unbiassed Opinion


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Guest carasky

Arh will i trully get an unbiased opinion on this?

how do these 2 engines compare for

1/ The ability to get max HP from a stock block

2/ Durability

3/ Fuel consumption.

I have driven a mildly worked 1JZ and was very impressed with all the above.

I am looking for a light car that has this conversion but they are not plentiful.

there seem to be a lot more RB25s around so I was wondering how they compare.

I realise you will be all toyota lovers here and wanna shoot be for such a heathen question, but maybe there are some out there with the knowledge?

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1JZ wins on points 1 and 2... loses on point 3. If you're worried about fuel consumption you shouldn't own a sports car... so therefore 1JZ > RB25 :D

I've seen a couple of AE86's now with 1JZ, but god knows why you'd wanna put such a nice engine into a bucket of rust and bolts. 1JZ swaps into ceffy's are rather common overseas, but locally 1JZ into cressida is king. If you have about $20,000 buy a JZX100 Chaser, if you have about $15,000 buy a JZX90 Mark II, both come with 1JZ's and are fairly nimble.

I know a couple of guys in NSW running 1JZ's in silvia's and the workshop I'm with (driftline in campbellfield) is currently putting a 1JZ into a 180sx ute (roof chop).

no shit... plus you don't need a huge turbo as its a pretty light car... classic looks (no plastic or fibreglass)... add a chin spoiler (old school style) and some wide rims with plenty of dish and your done... all whilst still having enough room in the engine bay to smuggle small Mexican children... or smack... you know whatever floats your boat

zoom did a 1jz 260z...

I would go a 1JZ if i could, i compare the 1J to the rb26, not the rb25 :P torque, bulletproof etc.

I own an RB25, and it is an okay motor, heaps of aftermarket support(where the 1J lacks compared to the 2J) but there is a reason i am pushing my GF to put a 1J in her supra... even the 7M isnt a bad thing*runs*

-Ryan

:)

I've seen a couple of AE86's now with 1JZ, but god knows why you'd wanna put such a nice engine into a bucket of rust and bolts. 1JZ swaps into ceffy's are rather common overseas, but locally 1JZ into cressida is king. If you have about $20,000 buy a JZX100 Chaser, if you have about $15,000 buy a JZX90 Mark II, both come with 1JZ's and are fairly nimble.

the AE86s are light where as the chasers are heavy

its all about power to weight ratio.

less weight = more acceseration, braking and corners from a physics point of view.

i know the chaser would be a much nicer drive being new but the lighter car will perform (if setup correctly IE good suspension and brakes) you know what i mean.

Kev

Yeah well...

i am going a 1jz with a sigma.. lol early next year so watch out for the stealth GSR.. my mechanic just did a 300kw cresida 1jz conversion the front end lifts off the ground and the rear bar dropps a couple of inches it was great..

the AE86s are light where as the chasers are heavy

its all about power to weight ratio.

less weight = more acceseration, braking and corners from a physics point of view.

i know the chaser would be a much nicer drive being new but the lighter car will perform (if setup correctly IE good suspension and brakes) you know what i mean.

AE86 also sports a solid rear axle, piss poor breaks, horrible rear suspension geometry... plus you'd be hard pressed to find an 86 that doesn't creak, groan and shudder like its about to shed panels on you. The chassis twists on most of them more than that rear suspension.

I used to have an AE86 which I was building for track work... with a 160kw CA18DET i'd have the same power to weight ratio as a 300kw GTR. The bloody thing felt like a deathtrap every time I stepped in it even with an 8 point rollcage. Its just antiquated, steering's all oldschool, the shifter's not high up, just little things that add up.

i am going a 1jz with a sigma.. lol early next year so watch out for the stealth GSR.. my mechanic just did a 300kw cresida 1jz conversion the front end lifts off the ground and the rear bar dropps a couple of inches it was great..

A Sigma, man my Misses had one and at 140/km the car feels like every panel is about to fall off!

I wish you good luck on your project, I hope you get alot of enjoyment and pleasure out of your pride and joy. But what you are proposing would make very entertaining drive and more than likely a car that actually reqires alot of driver skill to control on the track.

I hope you find a engine choice that suits your needs. I look forward to seeing the finished project, because I think been taken for a spin in it would really show off what you are trying to do.

ive owned one VVTi 1JZ, 3 RB25s and 2 RB20DETs.

Go the 1JZ. Good solid power, strong bottom ends.

The RB has the advantage of a good note and loves to rev hard. 1JZ are a little Lazy when revving, and dont like revving too hard anyway, and dont have that RB howl.

Its up to you, they are both good engines, just ones more durable and smoother than the other.

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