L16 build, head advice

[obrut]

I picked up a complete L16 last year that "ran a few years ago and was rebuilt".  I opened it up and checked all the rods and mains, pulled the head and checked the cylinders and everything looks great.  The bearings look new and if it had a carb it probably would have fired right up.  I bought this so I would have something to put in my car while I gather all the parts I want for a L20B that I have that needs a full rebuild. 

 

While reading the how to book I was impressed with the BRE L16 engine build in the beginning of the book and though I could do something similar.  I measured the bores and they all measure within spec.  I put a wanted add on the forum and bought a set of L24 flat top pistons.  I bought a set or ARP rod bolts and plan to have the rods reconditioned and balance the pistons and rods.  Then hone the cylinders, put new rings on the pistons and put them in the L16.  I have a set of DCOE 40s and cannon intake, new hooker header (yes I've read all the opinions on this) and L18 cam that I'm going to use on the L16.

 

So I'm trying to decide which head to use.  I have a stock 210 that came on the engine that is ready to go with new seats and guides.  This head has been milled and measures 4.20, so this will help raise the compression.  I also planned to open the intake ports up to match the cannon intake and un-shroud the valves and eyebrow the block.

 

I also have an open chamber A87 that has the 35mm exhaust valves and has never been milled.  Using this head with the open chamber will reduce the compression but will have better flow over the stock 210 head.

 

My 510 is not a daily driver, I will be running 93 octane all the time, I'm not worried about mileage - at all and I'm a little familiar with side draft webers and the time and patience to tune them.

My question is,

port and un-shroud the 210 head and use the L18 cam and I should have about 9.3 compression ratio give or take depending on how much I eyebrow and un-shroud or

gasket match clean up A87 head and use the L18 cam and have about 8.5 compression ratio but potentially better flow and larger valves

 

I've searched and read and I know the L20B is the better engine to start with.  This is what I have and these are the parts I already have and that's what I'm trying to use, thanks for the help.

 

 

 

 

[datzenmike]

L16 stock bore with flattops and 210 head milled 0.48" or lets round to 1mm.  I get 9.9558 compression.

 

 

L16 stock bore with flattops and open A87 head. I get 8.8 compression.

 

 

The L16SSS and the L18SSS did use flattops but flattops alone do not make it an SSS. To be an SSS engine you need a closed chamber 219 or later 912 head* that can take advantage of the large quench area produced. Open chamber heads will only receive an increase in compression. It also requires an SSS cam. The closest thing to the SSS cam is the one used on the L20B with a 0.413" lift. It might have been used on an L18.... maybe.

 

* This head had monster 1.5" intake ports and larger 1.65" intake valves. In comparison the 210 head's intakes are 1.25" and 1.50" intake valves. I would set this rebuilt head aside or sell it and go with the A87.... which can easily be milled down some more if you like higher compression. While it has a similar intake port it has larger 1.65" intake valves and will breath easier. A U67 would be even better with 1.375" intake ports and it already has an L20B cam in it..

 

 

[Stoffregen Motorsports]

As I've said before, the casting number V912 is a very rare head. Not the best head ever, but a casting produced by Nissan as a replacement head meant to go to builders with the intention of porting them. So in stock configuration, it's a pretty good "SSS" head, but with small ports meant to be ported by the end user.

 

Yes,  Nissan corporate built some cool race parts back in the day. 

[obrut]

Thanks for the replies, the L18 cam I have measures out to 0.412" lift so its probably the same is a L20B.  I must be doing the calculations wrong when I check compression.  I get 9.6 on the L16 flat tops and 210 head and 8.5 on the L16, flat tops with A87.  Looks like I'm off by .3 on both, I'll go back and check again.

 

I'll have to pull the A87 apart and check the seats and guides.  This head already has the L18 cam in it that I want to use and has the larger exhaust valves.

 

 

[datzenmike]

My compressed gasket thickness is 1.2mm. The piston actually rises 0.1mm above the deck so this makes the combustion volume just over 0.5mm smaller and the 210 head is 38.5cc minus the 1mm milled off volume which is 5.4cc removed. You may have used slightly different numbers.

 

The L20B cam has two square nodules in the middle, one on each side. 

[obrut]

I used 1mm off as 3cc removed, the cam does have the nodules in the middle on both sides.  I call it a L18 cam because the A87 and cam came off a L18.

[datzenmike]

83mm pi R² X1 = 5.4cc This is missing combustion chamber volume and quite a lot. That's 2mm of chain slack added. (well within chain adjustment) or add shims under the cam towers.

 

It's been theorized the 210 head was designed for the L14 and was just easier to use on an L16. It's ok for a stock engine but a bit restrictive if modifying.

 

 

[banzai510(hainz)]

Don't waist your time and money,just drive the L 16 and put the money in the L20 instead of the L16 no matter what the How to Book used to say.

I have L16/18s and wish I started with L20s instead.

 

Edited March 6, 2019 by banzai510(hainz)

[datzenmike]

The How To Book is for extracting as much from the L16 as you can for racing. This includes extreme measures and expense for fractions of a hp that added up can be the difference between winning and loosing. Struggling to copy this on a stock car is almost a waste of time when you can just throw in a stock L20B for an extra 20 (ish) hp. So Hainz is right in a way and this is a reality check.... Now if you are just doing this for the fun of doing it (and bragging rights) then this is the best reason, but don't expect too much.  

[Stoffregen Motorsports]

Look on the back of the cam, there should be a stamping, either A, B or C. The cam should also have a casting number in along the length of the cam. The best stock US market cam ever was the U20 B cam.

[obrut]

I was referring to the stock l16 they performance tuned on the dyno.  I think they changed to flat top pistons and a SSS cam but stilled used the stock intake and carb.  I think the number was 105.2 hp before he had to stop.

 

I'm not expecting a lot and it is more to have something so I can drive for now and just for fun.

 

I'll check the cam tonight to see which one I have, thanks

Edited March 6, 2019 by obrut

[datzenmike]

 The L16SSS used a diferent head and intake with dual SUs. You won't get anywhere near 105. And 105 was probably when engines were rated in gross not net HP. My '76 L20B say 110 hp. In reality it's closer to just over 90.  

[Stoffregen Motorsports]

Back when we were racing ITC, and I was building engines for a living, our blueprinted stock L16's with Weber DGV, Nissan Motorsports header and 2.5" exhaust were cranking out 120-125 hp on Rebello's engine dyno.

[datzenmike]

You can increase your output by 15 hp just by using his dyno. 

[obrut]

I checked the cam last night and I did not see A B or C on the back of it.  I think I'm going to use the A87 head on the L16 and put it together.  I already have all the pistons, ARP bolts and gasket kit and now its only going to cost me the price of reconditioning the rods.  I'm not really shooting for a HP number I was just using the how to book as a reference or ball park.  The book says they used a stock L16 not a SSS and then added the SSS cam and flat top pistons.  I assume they are still using the stock head but maybe I read it wrong.  Regardless I'll have an engine that runs and I can at least drive my 510, thanks guys.

 

 

[banzai510(hainz)]

if motivated I would maybe portmatch the weber carb(ADAPTER) to the manifold. maybe open up the intake ports. run less valve lash.

Illinios is flat maybe try a 38/38 weber.

Edited March 8, 2019 by banzai510(hainz)

[obrut]

2 minutes ago, banzai510(hainz) said:

if motivated I would maybe portmatch the weber carb(ADAPTER) to the manifold. maybe open up the intake ports. run less valve lash.

Illinios is flat maybe try a 38/38 weber.

 

I was going to throw on some DCOE 40s and cannon manifold that I already have.... no rising sun hood though

[datzenmike]

23 minutes ago, obrut said:

 

 .... no rising sun hood though

 

Well there's a 5 hp loss right there... 

[DHale_510]

On 3/6/2019 at 2:09 PM, datzenmike said:

You can increase your output by 15 hp just by using his dyno. 

 

I ran backups with Rockwell's chassis dyno to Rebello's engine dyno back in the day. Several motors, Pinkie's 217hp 1800 and Bluebird's 285hp V8, but never an ITC nor my ITS Z motor. They agreed.

The 15hp statement seemed to come out of the midnight MOFO meadows BS sessions at Shasta.

I was never able to find anyone that could backup the MOFO meadows claims, nor even anyone that tried. It seems the northwest water has odd effects sometimes....

Dennis

[datzenmike]

I'm just trollin' ya.

 

Even if out (fill in w/e plus/minus amount) hp it's a great tool for tuning and points you in the right direction.

[Stoffregen Motorsports]

I wasn't going to react. Your trolling was ineffective.

[banzai510(hainz)]

sidedrafts are fine!!!!!! esp 40s for a daily driver

love see a photo of this car

 .

Edited March 8, 2019 by banzai510(hainz)

[datzenmike]

1 hour ago, Stoffregen Motorsports said:

I wasn't going to react. Your trolling was ineffective.

 

You were who I was after. 

 

[Stoffregen Motorsports]

Douche...

[datzenmike]

 

Wow that's high praise but I never got that far with women.