300 rwkw n/a?

[four-cam-man]

hey guys
got a mechanic building a 1uz for us. He reckons it should put out 240 rwkw, ithas forged pistons full porting to the heads, blueprinted, balanced, billett cams, rod bolts etc. Any info about getting it to 300 rwkw+ would be great

Cheers
mark

 

[Pro]

lots of CR, lots of overlap, lots of lift and individual throttle bodies will get you close.

a judicial bottom end balancing (like better than normal) will help it rev harder more reliably.

but 250rwkw out of an NA engine is a pretty good in anyone's opinion. 300 definitley isn't impossible, but will be hard.

i think tuned lenght inlet runners and exhaust headers will be mandatory and may make more difference than you realise.

 

[400ZED]

That is real keen.
not the cheapest way to make 300rwkw.
i would expect you would need to leave no stone unturned. like larger valves. and many mods as a stock motor will only accept 370' lift with out changig stuff. possible maybe but that is a hell of a lot out of 4 L

 

[Pro]

i dare say one of the supercharger kits available on here and an M90 would be the "easiest" way to 300rwkw.

 

[Peewee]

I doubt an M90 would get 300rwkw. It would run out of puff.
An MP112 would do it.
Bang for buck a twin turbo will do it on a last 9psi or so, providing the turbo's are still well within efficiency range.

100rwhp/L (NA) is a big ask and driving the motor at lower speeds will be dog.
I sure hope this isnt a daily driver.

 

[Pro]

you're prob right, you know. MP112 category there.

my pair of TF035's will be pushing 9psi...

 

[Peewee]

Make sure you have a good cooler....

And keep that tranny cold too.

 

[Peewee]

Oh, and seriously, ditch Delco.
Get Autronic or something like that.
It will be sooooooo much cheaper in the long run.
I am glad I didnt use it.
Delco has its merits, cost of product, and cost of tuning definately isn't one of them

 

[four-cam-man]

Thanks guys, the car is a weekender, transmission is r154. Built for circuit racing and hill climbs and registered for an odd weekend run in the sun.A mate has already made me a sticker for the rear, looks like the original- says "HSV - I just whipped one"
This is a project thats got way outta hand. But its cheaper to go forward than back (yeah right)
Don't want the supercharger or turbo option. (pondering..............)

 

[400ZED]

be diffenernt stick with the Na.
good luck to you

 

[Pro]

hey there's merit in high horsepower NA engines - but it's just easier these days to turbo/supercharge something to get it.

not to say it can't be done, it's just not the norm.

and after all - we all want something different, dont we?

the great thing about NA mods are, you can add a supercharger later!

and Peewee, yeah the tranny has a large alloy cooler and tiptronic controller that shifts in 0.5sec. torque convertor slip is greatly reduced from factory spec.

no intercooler yet - considering water injection till i get a good A2A made. i have a 13B turbo core coming soon, so i'll get another and make a 1 big one out of 2.

and yes - i'm considering an Autronic. the V8 Poopercars use them so they have to be reliable.

 

[MikeMan]

I would say that using a 3UZ bottom end with the 4.3L capacity would help.

Go for an individual runner conversion with a GOOD ECU. (MOTEC or Autronic)

Kelford Cams in Christchurch, New Zealand have a range of cams available including a full race profile or two.

 

[SCV8]

Get the heads done by someone who knows, and then use some tapered individual intakes that start out at 60mm, and taper down to 45mm, total length about 12 inches from the valve. The taper from the 45mm throttle bodies down to the now 40-something mm intake port should be done in the last 2-3 inches of manifold runner before the port entrance. Might be nice to extend the divider that's down inside the port up into the intake runner as well.
Some equal length, long tube tri-Y nice headers would be good too with 35-36mm i.d. tubing at the start, 60mm secondaries.
You're going to need to rev to over 7,000 rpm to get the numbers you're mentioning, but will have plenty of midrange torque still if you tune for this rpm and not much higher.
Some surface fire plugs like those on the V6 Tacoma trucks would help a tad too.
That's what I would do anyways.
If you really want to go nuts you can have a custom 180 degree crank made from some good steel, custom cams, dry sump...