521 w/ a crown turbo L18

[fisch]

Not mine (I wish!) But here's a very cool '72 521 w/ a l18 w/ a crown turbo.

 

Anyone have experience with these turbos in their truck? Good? Bad?

 

Here's the descrption.

 

"1972 Datsun 1300 P/U with Crown turbocharged L18 sucking through Weber 45 sidedraft, rebuilt 5-speed, 3.'70 rear ratio,bed and body very straight, very quick."

 

I posted the ad I found in the for sale section, but thought it might be a good discussion for here.

 

Here's the link.

 

http://www.oldcartrader.com/ocdetail46197.htm

 

 

 

 

[fisch]

And for the sake of discussion here are Mike's insights on the gears. Hope you don't mind Mike, I'm learnin' here!

 

"Don't understand the 3.70 gears. The stock 4.88s would get 'into' the turbo way quicker. Even the 4.375s from an L16 would be better. Got the o/d 5spd to make up for it.

 

The 521 has the lines for two tone. Not sure if the 620 would look right with it's lower line that arches over each wheel well."

[Bleach]

3.7 is too tall

4.11 or 3.9 would be good if it is actually tuned well for midrange power. Carbbed turbos rarely are all that powerful.

[Cruzn620]

i wanted to see pics of the actual turbo set up. looked like a clean truck though, probably worth the 3k price tag.

[fisch]

Here is a shot of a crown turbo setup, out of a car. This doesn't look like a 4 banger though.

 

[Cruzn620]

damn websense is blocking photobucket...i'll look at it when i get home. thanks for the link!

[fisch]

Found more info on the subject here. And a photo of a crown turbo in a car (L16 I think).

 

http://www.newprotest.org/projects/510/turbo_L.pl

 

Photo:

 

[Fineline]

The crown kit was a cast iron adapter that bolted to the bottom of the stock exhaust manifold and horse shoed it to a turbo flange. They used Rajay turbos which for the time (late 70's?) were good tech but by todays standards are out of date. The kit basically came with an adapter, turbo, manifold hat, and carb mount to mount the carb before the turbo hence the name "draw through". These systems can not be intercooled so they are fairly limited in how much power they can produce. People have used h2o or methanol injection to get more power with some success but definately out of date with modern fuel injection.

[Cruzn620]

holy crap that was a lot of info...i'm really glad i abandoned my idea to turbo my L20 at this point. there is pretty much no way of getting 350hp out of a carb + turbo set up at our displacement levels

[fisch]

The crown kit was a cast iron adapter that bolted to the bottom of the stock exhaust manifold and horse shoed it to a turbo flange. They used Rajay turbos which for the time (late 70's?) were good tech but by todays standards are out of date. The kit basically came with an adapter, turbo, manifold hat, and carb mount to mount the carb before the turbo hence the name "draw through". These systems can not be intercooled so they are fairly limited in how much power they can produce. People have used h2o or methanol injection to get more power with some success but definately out of date with modern fuel injection.

 

Awesome info fineline! So they are not up to snuff by today's, but how much better are they over a stock setup? Would you see a satisfying performance difference.

 

To me this setup has a cool old school vibe to it. Which makes it interesting. But I am weird like that. This could be a neat way to get a little more pep out of an L16-L18?

 

Not that I am pursuing this! I gotta get mine down the road with what I have first!

[kiznook]

you can make power with carbbed turbo L series...

 

Keith L. - 247.8 HP @ nnnn RPM ' date=' ??? Lb-Ft @ nnnn RPM

Car - 1973 2 door

Engine - L20B, U67 head, Schwitzer 3LD-229/0.87 Turbo, Weber 32/36 DGV, 3" Exhaust, Cam is a proprietary Specialty (secret) grind, BP9ES plugs, 14 psi manifold pressure,

Fuel - VP C-16 (turbo race fuel with 6% lead, rated at a whopping 117 (MON) octane!!!) for the dyno, but normally it's "only" 100LL fuel

Transmission - '72 - '76 non-US z-car 5-speed, also Nissan Comp "close ratio overdrive P/N 32010-N3130"

Differential - 4.625 R180 LSD

Tires - 21.5" tall 13" diameter rim (Panasports)[/quote']

 

from this thread

[djmoreron]

wow, this truck is very close to me.

 

so how do you cool the old school turbo if its not intercooled?

[Bleach]

you can make power with carbbed turbo L series...

from this thread

 

well, you 'can' but its not a good method. Seems fishy to me and geared super low. Also, he did 3rd and 4th gear pulls but doesn't know for sure which one that was.

undersized tires, 4.625 rear, and maybe a 3rd gear pull? Please... you never do a 3rd gear pull on a dyno. You use whatever gear is closest to 1:1 ratio

the torque numbers are greatly exagerated with lower gearing like that, and horsepower is torque over time. basically, I don't even believe it with those "dyno" results. an SR20DET at 14psi runs about 250whp

[Cruzn620]

i'm with bleach! also, 250hp is 100hp under my goal and he's having to use VP race fuel!!! i think the KA24DE swap and about 15psi is going to get me near 300...i can use NOS to make up for the rest. but that was some really good reading!!!!

[Fineline]

wow, this truck is very close to me.

 

so how do you cool the old school turbo if its not intercooled?

 

You dont have to intercool the intake charge for a forced induction setup. Supercoolers and turbos alike were non intercooled for years. Some still are. Non-intercooled setups are limited in the boost they can safely produce though. It all comes down to keeping the fuel stable before ignition. The higher the abient temp of fuel the less stable it is therefore detonation or pre-ignition. This is muy malo in a forced induction motor. Especially one with cast pistons as in the L motors.

 

Even a draw through carburated turbo making 7 pounds of boost or so is going to make more power than stock. The problems with the Rajay turbos was there "lag" time. They wouldent spool up untill 4000-5000rpms or so depending on the motor so you were close to redline by the time you were making good power. You can overcome this a bit by widening out the lobe center on your cam to create more exhaust backpressure or upgrade the turbo. Modern compressor and turbine design allows a turbo to spool up and make boost much lower in the powerband.

[DISLEXICDIME]

i have an engine air box for my turbo set up i am putting together so i can intercool my carb set up.

 

here is my buddy's old l16 carbed turbo car pushing 12 pound's of boost let me tell you it was scary fast http://www.cardomain.com/ride/549284/3

[datzenmike]

you can make power with carbbed turbo L series...

from this thread

 

i have an engine air box for my turbo set up i am putting together so i can intercool my carb set up.

 

here is my buddy's old l16 carbed turbo car pushing 12 pound's of boost let me tell you it was scary fast http://www.cardomain.com/ride/549284/3

 

Keith's set up is a blow through with intercooler. Modified 32/36 Weber carb-in-a-box, methanol injection, and 10.5 to one compression.

[DISLEXICDIME]

I have the same blow through intake and exhaust manifold that keith started out with.

 

 

Keith's set up is a blow through with intercooler. Modified 32/36 Weber carb-in-a-box, methanol injection, and 10.5 to one compression.