My Hair Brained L16T / SSS idea, advice please

[Tom1200]

A friend found a rusty  4 door 510 with a L16T/ SSS motor (could be L18) and allegedly the guy just wants it gone.

 

So my hair brained idea is to replace the  A12 & A15 motors I've been running in my vintage race 1200 with the L16.

 

Background: My A12 is making 78-80hp at the wheels & the the A15 makes 99hp at the wheels. On both motors I use GX head with the ports cleaned up and 39mm flat slide carbs. The A12 uses he stock GX  cam and the A15 is using a Delta 278 cam .420 lift 278 duration. I rev both motors to 8100.

 

Regardless of whether the motor is L16 or L18 I'd simply clean up the ports, add a mild cam and call it a day. 

 

There are a couple of issues with this plan:

 

I run very low gearing, the stock A-series bottom end will rev to 8500rpms and I have no idea what sort of RPM the standard L series bottom end will tolerate. I'd need to rev the L series to around 7500.

 

I'd want this motor to produce around 110hp at the wheels without having to do a huge amount of modifications beyond a cam & mild porting and this may not be very realistic. I could adapt a manifold to fit the flat slides from the A-series.

 

Any and all thoughts welcome.

[datzenmike]

It may just be an ordinary 510 but with an SSS intake and SUs that came over on an import engine. A real SSS engine will have an original 219 number head. Just look along the bottom edge of the head above the block between the #1 and #2 spark plugs. If it's a stock 210 head then just a vanilla 510 with side drafts.

 

For engine ID look behind the dip stick handle on the flat boss on the top edge of the block.

 

The 219 is a closed chamber head with 1.5" intake ports and worth a lot even if only as rebuildable. The L16SSS also had flattop pistons, but you will find out when the head comes off

 

All L series blocks have 5 large main bearings and are bulletproof.

 

L16 about 70 hp. The L16SSS is 100 PS or 98.6 HP Red line for a 73.7mm stroke is 8,300 RPM (I've heard the SSS has a fully counter weighted crank)

L18 about 80 hp, The L18SSS is 115 PS or 113.4 HP (also has flattops and 219 head) Red line for a 78mm stroke is 7,800 RPM

 

KA24E main bearing compared to an L16,18 or L20B. Wrong the one on the left is the L series.

[iceman510]

Tom, in what class/sanctioning body do you race?  Is this engine swap legal?

 

L-series can handle 7500 RPM, but I would probably not do it on stock valve springs and components. I ran my L16 to that level when I had my vintage 510 race car.  Upgrading the rod bolts and some polishing and shot peening are probably in order, especially if the rods happen to have the early smaller 8mm diameter rod bolts. Upgrade to ARP or at least the Z/later L motor 9mm bolts.

 

Standard L16 cranks are not fully counterweighted either.  I have not heard of that being a huge issue at club level racing.  There were 6 bolt fully counterweighted Nissan Comp cranks, but rare and hard to find.  I have some spare cranks if you are interested and decide to go this route (not comp cranks).  

[Icehouse]

^What he said.  If the class allows a 1.6L run a SR16VE.  revs high and will run forever in stock form.  

[Tom1200]

I run with VARA; with the A12 I'm running in C-sedan, with the A15 I get thrown into VARA's GTL class.  In GTL I can run up to a 2.0 motor as long as I meet the rule set for a recognized sanctioning body.  The Australian IPRA rules allow for  everything from SR20 to L series engine.  The only reason I'm thinking about this is I can get the motor cheap...…….like $500 cheap.

 

The L16 is also fairly light and at the level I'd run it would probably do OK on pump gas.

 

Before anyone says put the money towards a newer motor note that I've switched to running my 87 Novakar Formula 500 at VARA so the 1200 will likely see more track day duty than actual vintage racing.  I love the 1200 but from a speed point of view it's no comparison

 

[datzenmike]

The L20B is more or less a stroker L16. The crank throws are longer so 7K red line, and the block is 2/3" taller. It weighs about 25 pounds more than an L16 and it DOES have a fully counter weighted crankshaft. 

[Tom1200]

Understood on the L20 but the fit starts to get really tight in a 1200. Realistically the head if it is truly the 219 SSS head is where the value is, if the motor is not a SSS I will be walking away from it. I don't even know what trans is in it yet  so that's a consideration as well.

 

 

[Icehouse]

Our L series lasted less then 3 hours from fully rebuilt to hole in the block.  Our SR has lasted 3 years of 4 weekends a year 16 hours a weekend of endurance racing.  It blows my mind how many hours it's spent a 6000-7500 RPMs.  Dollar to hour the SR is so damn cheap!  A K20 might be the best option.  They are mega cheap and plentiful.  I'm just Nissan biased.  Or even get a Sentra SR and convert it to RWD.  

[Tom1200]

All I ever seem to find in SR20s is either FWD or turbos.  A turbo motor puts me in with V8s

[carterb]

NA RWD SR20's are not easy to find anymore - you are right.  And they are expensive.  But expensive is relative.  And building and re-building a race motor that is on the edge to match the same factory output as the SR20 will surpass the cost very quickly.

 

--carter

[Tom1200]

Carter keep in mind my "race engines" are about 60% of an actual race engine. I'm getting no less than 5 seasons out of an A-series motor. IF I ran an SR20, I'd run it bone stock.

[Stoffregen Motorsports]

When I was racing ITC and working for Rebello Racing, our blueprinted L16s were making 120hp at the flywheel. That was a stock blueprinted motor with .040" over, a U20 cam, a shaved TK head for about 10:1 CR , re-curved distributor, Nissan Motorsports header with 2.5" exhaust and a Weber DGV on a A46 intake manifold. The usable rev range topped out at about 6200 rpm's.

 

A SSS head (with big valves) and a cam would likely bump the HP up to about 130. Add higher compression pistons and you're getting closer. More mods than that and you're getting into GT specs, albeit very early GT. I do remember dyno-ing other builder's GT4 engines and seeing as little as 150hp (flywheel). Top GT4 L16 engines get into the 230hp range, but only last a few races before they need a freshen up.

 

If you don't have a couple thousand bucks to spend on the L16, I would stick with the A motors you run.

 

Funny thing is, when I was young, I thought there was nothing better than an L series motor. Truth be told (and a couple decades later) I have warmed up to the SR20 engine. I don't like how they look in the vintage engine bay, but they are definitely a better motor and could get you the desired HP very easily.

Edited December 5, 2020 by Stoffregen Motorsports

[datzenmike]

1 hour ago, Stoffregen Motorsports said:

When I was racing ITC and working for Rebello Racing, our blueprinted L16s were making 120hp at the flywheel. That was a stock blueprinted motor with .040" over, a U20 cam, a shaved TK head for about 10:1 CR , re-curved distributor, Nissan Motorsports header with 2.5" exhaust and a Weber DGV on a A46 intake manifold. The usable rev range topped out at about 6200 rpm's.

 

 

Ahhh the infamous Rebello dyno. Sounds a little ambitious adding 50 HP with only a L20B cam, a 32/36 and some compression.

[Stoffregen Motorsports]

Whatever.

 

If you didn't have a Rebello engine, you didn't win a race.

[datzenmike]

 

 

Winning is still winning.

[Stoffregen Motorsports]

A lot went into the blueprinting process. Finding the right small bolt rods and crank for the lightest rotating/reciprocating assembly, meticulous setting of the bearing clearances and thrust, dialing in the cam to the thousandth of an inch, knowing which way to pull or push the intake manifold to ensure best port alignment.  It isn't just one big mod that makes the power gains. It is tons of little ones that add up.

[Tom1200]

 

On ‎12‎/‎5‎/‎2020 at 1:15 PM, Stoffregen Motorsports said:

A lot went into the blueprinting process. Finding the right small bolt rods and crank for the lightest rotating/reciprocating assembly, meticulous setting of the bearing clearances and thrust, dialing in the cam to the thousandth of an inch, knowing which way to pull or push the intake manifold to ensure best port alignment.  It isn't just one big mod that makes the power gains. It is tons of little ones that add up.

    

I was hoping you would chime in. It is the little things; a proper valve job is worth 5-6hp on my A-series. Just cleaning up the ports added almost 10hp to an otherwise stock A12GX motor. Half a point of compression is worth 3hp. I'm probably giving up 3-5hp on my A15 by just slapping bearings in it and calling it a day rather than being anal about the clearances.

 

Ironically with an SR20 in the car I would be in the same catchall class that I am with the A15 or L series engine. If all I did was clean up the ports and install a free flowing exhaust on a SR20 motor it'd likely be making 140-145hp at the wheels.

 

Thanks for the input...……….sounds like I should just leave it with the A-series as the mildly tuned L16SSS is only going to be about a 10hp boost over my mid-level tuned A15.

[Stoffregen Motorsports]

I haven't been here much lately. I found a Sprite forum and have been lurking around there. But I know where you are coming from. A friend of mine who writes for offroad magazines keeps bringing up the subject of having me build him a 3 link suspension for the front of his crawler, but we always come back to the same conclusion - it works just fine with the leaf springs, so leave it alone. Sometimes that's the hardest thing to do - just leave it alone.