first thing i did was buy a how to modify your L series...full of helpful stuff in it and full of info. pretty much is a step by step, i had a very good u67 head for high comp, the biggest cam grind you can get from a standard cam, flat top forge pistons(ka24 pistons) ka24 crank and much more. Would have been an easy 150hp but never got dynoed. But if you wanna go good you will need to make those points go bye bye, you will need to spend the cash on an electric dizzy. will ned an electric fuel pump and reg to match either dcoe40's or 45 to make sure they have there much needed pressure at all times.....and will need a dogleg gearbox as it will last

h89 head on a l20b?

sorry i meant u67...hehe my bad

Engines from the factory are rated at the flywheel, never at the wheels. So a stock L20B was 110 HP right from the factory with a single Hitachi carburetor.

To make 150 HP (at the flywheel) you need twin 45s. 40s will not do it without the expensive work previously referred to -- or a turbo!

The Datsun U20 engine (also 2-liter) had a factory 150HP option, which was basically twin 44 mikunis instead of twin hitachi 38s + a higher RPM camshaft. The basic performance difference between U20 and L20B is the cylinder head design, hence the need to choose a good cylinder head.

V91 versus U67 cylinder head. Dunno.

219 and N04 were the SSS heads. Nissan competition sold the U06 as an SSS head. Dunno if those are the ones you want on an L20B, but for L16 & L18 are the good ones.

210 and N21 are the common heads and are OK, but not a great hi-RPM choice.

A good L-series head works just fine when done right. Just do minimal bowl work and port matching (not fully ported) and have to rev it up (cam and springs) to make 150HP. And let it out with 2.5" exhaust. Use 9.5:1 or 10:1 compression.

Oh and it won't work without the right cam. All this work is estimated at $2000-$2500 USA for the L20B.

A stroker 2.3 L20B (L cylinder head, but using Z-series block) makes 150HP -- at the wheels, so higher at the flywheel -- using similar components.

Also note that a stock junkyard KA24DE makes over 150HP flywheel with zero mods.

2500 in parts alone is expensive for NA where he can use a Z18et
setup or go Draw through turbo which is cheaper and has more potential
with stock rebuilt bottom end. L series are mostly bullet proof and wont
need to go over 6500rpm to make 150hp ate or 150hp atw.

DIY
Log style manifold 250-400 aud, NOS equiv non ball bearing T28 or T3
direct from Japan 600 aud or rebuilt prob 400-500 aud, SU 150aud,
pipe work $150, DIY H2O inj $100 + tuning.

Turbo Parts alone 1000-1500aud or the cost of twin 45 carbs.
You can also find some turbo kits S/H for under 1K aud on Ozdat.com

Unfortunately a ka24 is too big in most states where the SR isnt and
all pollution engines.

Brett I went in robs ute with your old motor and it didnt do much for the effort and money you put into that motor

If my ute doesnt go better than robs ill put my ca in

OK I have to ask: What is the intended use for your UTE, street driver, Track car you can still drive on the street etc.

I've found with all motor projects whether 2 stroke street bike, tow vehicle etc figure out what you want it to do and worry about the numbers later. What suspension and brakes are currently on the car now and what gearbox are you using? 150HP Ute with stock brakes and suspension won't be much fun.............it will feel twice as fast as it really is but it won't be fun. You can probably get 190HP out of the motor but without a close ratio gearbox the car will be constantly off the power band at the worst moment.

Figure out what your budget is $500 or $5000 and go for a broad based approach for a street car. You should be able to get 135-140HP pretty easy with a flat torque curve. Motor building is pretty straight forward, you just need to build it up as a matched set. I.E. don't fall into the trap of over carbed under cammed. IF your budget only allows for a 32/36 DGV carb then go with a moderate cam etc. If you can go with 10-1 compression, DCOE's, head with the ports cleaned up and matched exhaust you'll likely be way happier than if you went after that last 10HP but gave up drivability.

Case in point I have two Vintage MX bikes a 76 YZ125 and a 77 CR125 Elsinore: you can turn faster laps with the Elsinore but you're working twice as hard and the slightest bobble and will instantly drop 2 seconds a lap...........the Elsinore makes 3 more horsepower. I'm in good enough shape that I can still run 5K, on the YZ I can go flat out for 5 laps (15 minutes) but on the Elsinore at the end of lap 5 I'm spent, sure I've gone slightly faster but the fun factor takes a big hit. Sure I could train more but again, this is supposed to be fun.

Sorry to be so verbose but get the L series book, figure out what your budget allows, forget the "number" and then get the best set of parts (head, cam, porting carbs) for your system.

Tom

well jesse i think the only reason it wasnt fast was because of rob not my motor....plus you have to realise the last person who had it before him....and also not having the electric ignition really didnt help it