I keep on thinking about building a new engine for my turboed 180b I have about 140rwkw out of a stock l20b bottom end with a stockish A87 head running about 0.6 bar. t25

If building a new motor what would you do. How much power would you expect?

Either your dyno reads high or your quoting flywheel kw's (or RWHP) with such low boost and a t25.
Anyhoo, to answer your question:
Not enough to justify the expense. Apart from nostalgic reasons id go twin cam all the way thesedays.
With a std cam and mild port job on a U67 head i only got around 165rwkw out of mine using a hiflow rb20/25 turbo at 21psi.
Compare that to fj's and sr's that are internally std and are punching out around 180-200rwkw, its a no brainer...

great advice above,

port velocity becomes less important, and boost is a measure of restriction not flow. the L series heads have great velocity due to port shape but just cant flow a great deal of CFM due to bowl shape/size.

As Nick says, the twin cam is the better way to go. more square cm of available space to push air through will mean more power for the same boost level. FJ CA SR is the way o go if you want to add boost.

cheers!

Just drop compression and up boost for more outright power but id date say 145kw on low boost would have great off boost response,making it more fun to drive.

Don't go chasing power at sacrifice of driveability on street

So leaving it the way it is mught be the go then... turbo lag is none existant atm

do you have any picks of your set up? would love to see it.

Is this Mark's old 180b? A light blue one?

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120Y 4DOOR SEDAN SR20DE WITH ITB'S

http://datsun1200.com/modules/newbb/vie ... post494892

I'm not to sure how my turbo set up is going to go but I've opted for high compression low boost. I've got an air research original draw through turbo with a 9 psi external wastegate with a 45 dcoe weber infront of it. Turbo's going onto a 9:1 l18w with a w53 head with huge ports and combustion chamber work I'm thinking I will have to reduce the came size once it's running. And honestly I'd be really happy with 180whp. But if you want big power like everyone's said go twin cam.

This sounds familiar, I hope the blue beast is still going strong!
I built this car and can confirm it certainly made 145ish kw at the tyres..
whatever you do, don't drop the compression! Its a good little combo and there is nothing to say it wouldn't love some more boost, use the megasquirt to control the Wastegate add some e85 and post the results, I wanna know how it performs!
how is it going aside from the gearbox issue anyway?
Mark.

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1975 Datsun 180b - EFI turbo L20b Sold

Yes this is Marks car, Been up in Far North QLD driving a truck back next week will have to take some more pics a post them.

Cars still going good. Doesn't get out and about often enough, Bluebird box seams to be holding together for me. Got some R32 bakes ready to bolt in and an Nismo LSD sitting ready when I get some CV's Made up.

Mark made wonders with the drivablity of the car and I won't change a thing unless I can keep it that way

Its been ages, and after 2 year finally got time and motavation to get the old girl going again.

will try and get her back together tomorrow

http://ozdat.com/forum/viewtopic.php?f=62&t=32113

good turbo L series doesnt need big hp
these engines shine in torque spread
with excellent mid range very fat curve

She Back together now
Had some problems getting fuel to the injectors, with some fire luckily didn't do much damage

here it running
https://youtu.be/53HfDACojrI

Good to see the old girl back in action.

_________________
120Y 4DOOR SEDAN SR20DE WITH ITB'S

http://datsun1200.com/modules/newbb/vie ... post494892