Building a L18

[JDH6]

Hi all, I am looking to build a L18 for track use along with street use, i currently have a stock L16. I was wondering what you all would recommend the best route? What parts to use to make a solid L18, any advice is greatly appreciated!

[banzai510(hainz)]

get a L20 to start with

[d.p]

2 hours ago, banzai510(hainz) said:

get a L20 to start with

 

Lol.  Man I don't know how you do it after all these years on this site with the same open ended questions over and over.   I admire your patience.  

[Stoffregen Motorsports]

Use the L18 block and crank, and the L16 rods with some 87mm pistons = 1900 long rod.

 

What carb are you going to run? If a DGV, then I would use a 27C cam on a mildly ported head.

 

This setup will last forever and make good HP (probably 125 or so with a DGV) and is super inexpensive to build.

[banzai510(hainz)]

6 minutes ago, d.p said:

all these years

I find out start with a bigger motor and not build the same motor 2 times as I did.a L16 and L18.

L Motor do a L20 if given a choice.

a stock L20 with 40mm Mikunis might be just as good as this long rod matching up this and that and all you had to do is Bolt on the carb set, Bam your done

[datzenmike]

Get an L20B. If a track allows an L18 they'll allow an L20B. Basically the block is 2cm taller at the top and 25% larger displacement than an L16. 12% more hp than an L18. Cost exactly the same to build one over the other. L18 were only produced for '73 610 and '74 710 and 620 so not a lot laying around. It will cost a lot to get 10 more hp from an L18 where an L20B makes thet all day.

 

On a really good day they make...

 

L16........ 73 hp* 

L18........ 83 hp*

L20B..... 93 hp

 

*All three are in Net hp. L16 and L18 were usually measured and posted in Gross hp so old books and the engine tags may say higher than this. L20Bs were in '74 and up 610s, '75 and up 610s, 620, A10s, S10s and the first year ('80) 720 so plentiful as weeds.

[iceman510]

29 minutes ago, datzenmike said:

 If a track allows an L18 they'll allow an L20B.

 

Not necessarily true depending on with whom/ what class he plans to run, but OP did not elaborate, so your point may be correct.

[Stoffregen Motorsports]

I like the simplicity of the older block L18 with the sideways breather port. The 1900 is such a great motor, which revs freely and also has good torque. Vs the L20B, I would rather have the 1900. This motor could be built for the cost of pistons, machine work and rebuild parts.

 

And yes, if the OP is following any kind of rules, some groups will allow an L18, but not an L20B.

[JDH6]

On 9/27/2021 at 11:07 AM, banzai510(hainz) said:

get a L20 to start with

I need to run an L18 for racing

 

[JDH6]

On 9/27/2021 at 2:06 PM, Stoffregen Motorsports said:

I like the simplicity of the older block L18 with the sideways breather port. The 1900 is such a great motor, which revs freely and also has good torque. Vs the L20B, I would rather have the 1900. This motor could be built for the cost of pistons, machine work and rebuild parts.

 

And yes, if the OP is following any kind of rules, some groups will allow an L18, but not an L20B.

Hi, thank you for the input I need to run an L18 for racing, I plan to run some sort of sidedrafts webers or mikunis. how would you go about building the best L18 engine. Thanks!!!

[JDH6]

On 9/27/2021 at 1:23 PM, datzenmike said:

Get an L20B. If a track allows an L18 they'll allow an L20B. Basically the block is 2cm taller at the top and 25% larger displacement than an L16. 12% more hp than an L18. Cost exactly the same to build one over the other. L18 were only produced for '73 610 and '74 710 and 620 so not a lot laying around. It will cost a lot to get 10 more hp from an L18 where an L20B makes thet all day.

 

On a really good day they make...

 

L16........ 73 hp* 

L18........ 83 hp*

L20B..... 93 hp

 

*All three are in Net hp. L16 and L18 were usually measured and posted in Gross hp so old books and the engine tags may say higher than this. L20Bs were in '74 and up 610s, '75 and up 610s, 620, A10s, S10s and the first year ('80) 720 so plentiful as weeds.

It needs to be an L18 to race legally. Otherwise I would for sure get a L20B

[Stoffregen Motorsports]

17 hours ago, JDH6 said:

Hi, thank you for the input I need to run an L18 for racing, I plan to run some sort of sidedrafts webers or mikunis. how would you go about building the best L18 engine. Thanks!!!

If you're racing, you've probably got bore size limitations, but there are no rules on rods. If you need to stay in the .040" over range, get some custom pistons with the correct pin height to use L16 rods. That's the basic B Sedan or GT3/4 combination. I would knife edge the crank and have it nitrided & cryo treated, and depending on how much HP you need, you may or may not be able to run stock L16 rods. Carillo rods used to be the standard, but there are knockoffs now-a-days which are about half the price.

 

Back when I was building racing engines for a living, a fully built L18 GT motor could make 230-240 hp, but required lots and lots of maintenance. A typical B Sedan (or 2.5 TA) back in the day, made about 180-190 hp with an L18.

 

You will also need a big oil pan, which I think you can still get from the usual Datsun guys. I think Ed Pink is the one who makes them.

 

Most of the power and cost is in the cylinder head, with carburetion coming in a close second. The bottom end is cheap by comparison.

[JDH6]

1 hour ago, Stoffregen Motorsports said:

If you're racing, you've probably got bore size limitations, but there are no rules on rods. If you need to stay in the .040" over range, get some custom pistons with the correct pin height to use L16 rods. That's the basic B Sedan or GT3/4 combination. I would knife edge the crank and have it nitrided & cryo treated, and depending on how much HP you need, you may or may not be able to run stock L16 rods. Carillo rods used to be the standard, but there are knockoffs now-a-days which are about half the price.

 

Back when I was building racing engines for a living, a fully built L18 GT motor could make 230-240 hp, but required lots and lots of maintenance. A typical B Sedan (or 2.5 TA) back in the day, made about 180-190 hp with an L18.

 

You will also need a big oil pan, which I think you can still get from the usual Datsun guys. I think Ed Pink is the one who makes them.

 

Most of the power and cost is in the cylinder head, with carburetion coming in a close second. The bottom end is cheap by comparison.

Thank you, aiming for 180-190HP, I know some 510 race cars are making 230 out of an L18, not sure if they are bored or not. what all would you suggest for head work? and what head to start with?

[datzenmike]

Bottom end is built for strength, top end for power.

[JDH6]

35 minutes ago, datzenmike said:

Bottom end is built for strength, top end for power.

Whats the ideal topped setup for power

[banzai510(hainz)]

Most of us here dont know these awnsers as we dont race but try to just improve on basic L motor stuff on the cheap. we can by swapping some stuff around.

Stoffregen Motorsports  .    

would know more than most on cam selection valve train ect.. to get the best and most and really the COST to get this.

 

to get this 180HP really is HUGE cams and min 44 to 50mm carbs running top notch and a distributor setup that is rock solid.  (crankfire???)

[iceman510]

That is not a simple answer.  All the factors need to be considered together.

 

Piston shape/compression ratio

Camshaft specs

Carburetion and venturi size

Valve sizes

Spring specs

Porting

and on and on...

 

 

get the How to Modify your Nissan/Datsun OHC Engine book, and read it thoroughly.  Or hire someone to build you one.

 

 

[datzenmike]

Everyone comes here wanting 180-220 hp then find out it's $12,000 and settle for a Weber and loud muffler. Hey if you are hard core Stoffregen would be who to talk to. Power ain't cheap.

[iceman510]

Incidentally, if you are in PA, I am in Michigan.  I have lots of L engine parts, including some L18 parts, and some to make L16/18 hybrid (frankenstein) combinations.  If you need some things I might be able to supply them.  I am planning on getting back into vintage B sedan type racing, and may need some of them, but the car I am likely getting has an L18 and a L20B already.  Probably need to keep one L18 setup as backup.

 

Also have spare oil pans if you need something to modify/get modified (DP racing makes these).  Also heard of another guy, Armando's Racing Pans out of El Paso Texas, but I have never talked to him. 

[JDH6]

46 minutes ago, iceman510 said:

Incidentally, if you are in PA, I am in Michigan.  I have lots of L engine parts, including some L18 parts, and some to make L16/18 hybrid (frankenstein) combinations.  If you need some things I might be able to supply them.  I am planning on getting back into vintage B sedan type racing, and may need some of them, but the car I am likely getting has an L18 and a L20B already.  Probably need to keep one L18 setup as backup.

 

Also have spare oil pans if you need something to modify/get modified (DP racing makes these).  Also heard of another guy, Armando's Racing Pans out of El Paso Texas, but I have never talked to him. 

For sure will reach out to you if I need some parts, thank you!

[JDH6]

1 hour ago, banzai510(hainz) said:

Most of us here dont know these awnsers as we dont race but try to just improve on basic L motor stuff on the cheap. we can by swapping some stuff around.

Stoffregen Motorsports  .    

would know more than most on cam selection valve train ect.. to get the best and most and really the COST to get this.

 

to get this 180HP really is HUGE cams and min 44 to 50mm carbs running top notch and a distributor setup that is rock solid.  (crankfire???)

Thank you

[JDH6]

5 hours ago, datzenmike said:

Everyone comes here wanting 180-220 hp then find out it's $12,000 and settle for a Weber and loud muffler. Hey if you are hard core Stoffregen would be who to talk to. Power ain't cheap.

I fully expect it to cost more then 2,000, I wanted to just see some recommendations on what people do. Sadly power is not cheap...

Edited October 1, 2021 by JDH6

[datzenmike]

Spend what you can on the head. Re-grind your old cam but when you get around 0.480" valve lift the valve springs are close to stacking so to go more you will need new springs and retainers and lash pads. If you have an L18 complete they came with A-87 heads. There are some over size valves. Ports are not huge on the A87 but you can grind them out or use a U67 which are slightly larger ports and valves to begin with. The L16 cast iron exhaust is good to around 150 hp but some L18 manifolds only 'look' this the originals. For spending only $2,000 I don't think headers are gong to be needed and spend the savings on something else. Good side drafts are $1,600 I think. I got a set of R-1 Yamaha motorcycle carburetors and made my own manifold. Each cylinder has it's own 1.5" or 38mm carburetor. $100 for the carbs and probably 2 to 3 times that finding out what not to do to make the intake. Intake materials only came to $40-$50 it's trying stuff that didn't work that cost a lot. Definitely get an EI (electronic ignition) distributor. If rebuilding the engine try to find L18 flattops to boost the compression. Flattops and open chamber head  is around 9.

[JDH6]

28 minutes ago, datzenmike said:

Spend what you can on the head. Re-grind your old cam but when you get around 0.480" valve lift the valve springs are close to stacking so to go more you will need new springs and retainers and lash pads. If you have an L18 complete they came with A-87 heads. There are some over size valves. Ports are not huge on the A87 but you can grind them out or use a U67 which are slightly larger ports and valves to begin with. The L16 cast iron exhaust is good to around 150 hp but some L18 manifolds only 'look' this the originals. For spending only $2,000 I don't think headers are gong to be needed and spend the savings on something else. Good side drafts are $1,600 I think. I got a set of R-1 Yamaha motorcycle carburetors and made my own manifold. Each cylinder has it's own 1.5" or 38mm carburetor. $100 for the carbs and probably 2 to 3 times that finding out what not to do to make the intake. Intake materials only came to $40-$50 it's trying stuff that didn't work that cost a lot. Definitely get an EI (electronic ignition) distributor. If rebuilding the engine try to find L18 flattops to boost the compression. Flattops and open chamber head  is around 9.

I believe I misspoke in the previous comment, I fully expect it to cost more then 2,000. Thank you for the reply with info for a cheaper build. What would be the ideal setup for an L18, I know it will cost a lot, that is okay with me. I am just trying to learn what all I need so I can start searching for the parts. What head would be best? Mods to the head? etc 

[Stoffregen Motorsports]

14 hours ago, JDH6 said:

I believe I misspoke in the previous comment, I fully expect it to cost more then 2,000. Thank you for the reply with info for a cheaper build. What would be the ideal setup for an L18, I know it will cost a lot, that is okay with me. I am just trying to learn what all I need so I can start searching for the parts. What head would be best? Mods to the head? etc 

I assume you're building this for vintage racing, and depending on which group you're running with there are more and less strict guidelines ad to what parts you can use. Some groups will allow 1980's GT4 style cars, while others want 2.5TA or BS style cars.

 

I typed out a good reply yesterday, but I don;t see it here. Wonder what happened to that...Anyway. Cost-wise, a fully prepped race engine costs in the neighborhood of $6k-$9k, with roughly $3k each into the bottom end, the cylinder head and the intake/carburetion. 44PHH Solex or Mikuni carbs are the most accurate vintage carbs, and can be purchased from guys like Mike Malone or Rebello or Ermish. Mike Malone build very nice carbs, which look better than new when done. You will also need an appropriate intake, like the rare BRE intake or Datsun comp intake, which are both very expensive. Troy Ermish is now selling custom, CNC'd billet long runner intakes that are very close to the Datsun Comp intakes. I believe he sells them for $600. Weber side drafts are also an option, but everybody expects to see Solex/Mikuni carbs on a vintage 510.

 

There are about four different cylinder heads you could use, A87, 219, V912 or even a U60. Any of these heads are going to need massive amounts of work done to them, and not just in the porting. The chambers need to be fit to the piston domes too. A large race cam and a sturdy valvetrain round out the package. Expect to replace valve springs every four or five races, or even at the track if you break one from an over-rev.

 

Everyone thinks the bottom end is the least important piece of the puzzle, but that's absolutely not the case. I mentioned earlier knife edging and nitriding the crank, possible custom H-beam rods (Carrillo) are both good insurance against failure. Custom pistons withe pop up domes will give you the roughly 12:1 CR, but as mentioned, they come "rough" and need to be fit to the combustion chamber and possibly cut for piston to valve clearance. The block should be o-ringed and the crankcase should be ground and prepped. Bearings need full grooves, with enlarged oil holes and clearances meticulously set. If you're going to use a distributor for spark, you'll need a brass drive for the crank, as the steel ones break under the stresses of racing.

 

I would not attempt your first engine build here. There are so many areas that can cause headaches or failure if overlooked or mis-measured. Full disclosure here, I worked for Dave Rebello for a decade building engines, and I do recommend them to build yours. Yes, there are other competent Datsun engine builders out there, but Rebello has built the winningest Datsun L motors for decades. You could also have them build you key parts, like the cylinder head, block machining and crank prep, and assemble the engine yourself, but for the couple thousand you may save going that route, it may not be worth the effort. Once you have a custom built engine, you could always do the rebuilds yourself, but I even advise against that simply because rebuilds are not very expensive (assuming you don't break anything on the track).

 

As far as Mike's suggestion to use motorcycle carbs and a stock exhaust manifold, due respect Mike, those parts will not fly on a vintage race car. For everyone I know, vintage racing is as much about the car as it is about the racing, and again as much about the people you race with. You have to at least try and build it era-correct.

 

Troy Ermish makes a very nice stainless header for about $600, or save a few bucks and buy his mild steel header. Both of them are near copies of the Datsun Comp headers of yore. A 2.5" exhaust will be required too, with or without muffler (mufflers actually work better than an open pipe, at least that's been my experience). And then there are other pieces like the correct distributor (Mallory tach drive being he coolest, and can be modified to use MSD internals for reliability), crank dampers, valve covers, water pump pulleys, etc that all lend to the overall effect.

 

Really, what it boils down to is how correct do you want the car to be? If you're into it for the vintage vibe, spend some time on the phone and scour the classifieds for the cool vintage parts. We haven't even discussed the trans or differential yet, and those can be quite expensive too. Should you be lucky enough to find a close ratio direct drive 5 speed and R180 limited slip, expect to shell out another $6k or more for those.

 

I've had some super rare Datsun race parts and there really is nothing cooler than the OG stuff. When I got out of the Datsun world, I sold everything I had to Troy for a lump sum. I had over 11 legal size pages of parts, ranging from an NOS finned aluminum 7 quart oil pan with the part number sticker still on it, to a pair of carbs that were actually on the #35 BRE 510, to NOS DD 5 speed rebuild parts, magnesium 13x7 Libres, R160 and R180 LSD diffs plus tons of other hard to find parts. I almost had my hands on a one-off oil to water heat exchanger that BRE used in the '70s, but I couldn't afford it at the time. Do I miss Datsun racing? Yes, but I will never own another 510. As Thomas Wolfe said - "you can never go home again", which is why I'm now building an Austin Healey Sprite to go vintage racing...