Twin cam head for the L6 from Derek at Datsunworks

[Ineptitude01]

On 6/6/2021 at 4:04 AM, Derek said:

The only footage other than my car and 005 is the dyno pull that ZCC did.

https://www.instagram.com/p/CMKqD5BHwrr/

 

Holy MOLY. I thought I was going to be able to live without one of these heads, but now I'm looking around for stuff to sell on eBay. Sheesh! Thanks a lot, Derek! 🥴

I think I asked before, but it sounds like nobody has done any forced induction yet? I'd be damn curious to see what a stock bottom end with a nice modern turbo could push through that head.

[Derek]

1 hour ago, DuffyMahoney said:

Tioga knows his stuff.  

He sure does. 

1 hour ago, DuffyMahoney said:

The whole setup looks great Derek!

Thanks Duffy. Now I'm trying to figure out if I can make it work on my VVT setup.

[Derek]

7 minutes ago, Ineptitude01 said:

I'm looking around for stuff to sell on eBay. Sheesh! Thanks a lot, Derek! 

 I told you guys before don't blame me blame Tony D. I think that has a nice ring to it.  Like an orange juice commercial. 

 

7 minutes ago, Ineptitude01 said:

I think I asked before, but it sounds like nobody has done any forced induction yet?

Not yet. It's a pretty pricy head to blowup. 

Edited June 7, 2021 by Derek

[AydinZ71]

4 hours ago, Derek said:

 I told you guys before don't blame me blame Tony D. I think that has a nice ring to it.  Like an orange juice commercial. 

 

Not yet. It's a pretty pricy head to blowup. 

Yeah I think your bang-for-the-buck on this head is NA. Once you are going forced induction, you can boost more to overcompensate the shitty flowing L heads. Clearly the DOHC will make more power at less boost, but I think the sexy factor is making big power in an NA application for road racing. Just my opinion

Edited June 7, 2021 by AydinZ71

[HS30-H]

42 minutes ago, AydinZ71 said:

Clearly the DOHC will make more power at less boost, but I think the sexy factor is making big power in an NA application for road racing.

 

What class of road racing?

 

As far as I can see, a head like this isn't legal in any class where it would be competitive.

[Derek]

38 minutes ago, HS30-H said:

As far as I can see, a head like this isn't legal in any class where it would be competitive.

 

Is there a class it could even run in at all? If so how much horse power would it need to put out to be competitive? I'm not into road racing so I have no clue.

[AydinZ71]

4 hours ago, HS30-H said:

 

What class of road racing?

 

As far as I can see, a head like this isn't legal in any class where it would be competitive.

True  At least not in SCCA. Can’t run it in ITS, EP. 

 

Not sure about the rules in Vintage racing. I have always had trouble finding the comprehensive rules for that.

 

Still, I believe there are some exhibition track days, hill climb, time attack, etc. 

[AydinZ71]

3 hours ago, Derek said:

 

Is there a class it could even run in at all? If so how much horse power would it need to put out to be competitive? I'm not into road racing so I have no clue.

@HS30-H is right. You wouldn’t be able to run this head on any of the classes in SCCA that run in “nationals”. Still, there are other regional road racing and vintage series races that have looser rules. More on the exhibition side, without a trophy 😂

 

Even for exhibition racing, the “cool” factor of running a DOHC L-series would get a lot of attention. 
 

HP needs would depend on the track, but given EP runs an L24 w/ SU’s, I think you will have plenty of power! The EP L24’s are in the 230-260hp range, but the torque band is limited to the higher RPM’s and typically run a redline 8-8.5k. No expert here, just spent a lot of time asking question from those who are. 
 

What I would be most excited about with this head is the potential for a broader torque band, and higher peak torque. The valvetrain will need to be super stable to run those high RPM’s though. You could test it on a block with pauter rods and forged pistons with valve reliefs, if you were interested in “stress testing” the head well past the OEM redline. 

 

 

[Jeff]

17 hours ago, Derek said:

 

Is there a class it could even run in at all? If so how much horse power would it need to put out to be competitive? I'm not into road racing so I have no clue.

I don't know about being competitive, but it can run in the NASA Super Touring classes.  It's all about power to weight with brakes and suspension pretty much wide open.  I imagine it would compete in ST2 or possibly ST1 depending how much wheel horsepower it's putting down.  Time Trials run the same rules and I currently run TT3 in my 2014 SS Camaro, mostly at Sebring but I was just at Daytona a little over a week ago.  It's a fun group and they are nation wide.

 

Here is the form, it's stupid simple.  Classification Form

[Leon]

I was going to suggest NASA ST but it would be a tall task to make a Z competitive against GT3's and Viper ACR's. Not saying it can't be done but... anyway, we've gone way off topic on this fantastic thread.

Edited June 8, 2021 by Leon

[bradyzq]

@AydinZ71, with the VVT on the intake cam working, the torque band should be stupid wide.

 

I'm curious to see a dyno plot comparo with VVT tuning, and without, but I guess that is a ways off... 

[Derek]

Well If I ever get my 3.15L built I'll have some numbers but the the motor that is currently in it there is no reason to dyno it.

[madkaw]

11 hours ago, Derek said:

Well If I ever get my 3.15L built I'll have some numbers but the the motor that is currently in it there is no reason to dyno it.

Why not ? Wouldn’t at least be a base line ? 
I know its a bit of a PITA to coordinate and cost $ , but inquiring minds want to know

[Derek]

It's not a good platform. And it won't matter how many caveats I put out there on how tired the motor is or the lack of compression ratio etc etc the internet truth will be "that Datsunworks head only made XX hp". My butt dyno says it is faster than a SOHC but not by much since the CR is way way low. Probably in the 9:1 range.  If I needed the data I would do it in a heart beat but I don't. 

[supernova_6969]

Hi Derek.

It`s been a while (time wise) that we've seen some form of an update in production.  

I'd be curious to see a breakdown of all the heads you`ve made and what happened to them.

 

for example 

 

headd 001- - prototype, scrapped

headd 002, prototype, in my car

head 003, vvt prototype, scrapped.  

head 004 - client was dynoed on a 3.2 to xxx hp..

head......

*****note that all these are made up!!!! 

 

something like that.  maybe including the future plans, like how many heads have been ordered and are "in production".

 

thanks!

 

s

[Derek]

As it stands I have been paid for 10 cylinder heads. The only ones that are actually running and drivable is SN001 which is mine and I have over 7K miles on it, SN005 has over 10 K I think and SN010 which is in a Zcar Garage/Rebello build. Probably not to many miles on it but the word I got on that one was the owner was very happy. That car is a 3.15L I think. They haven't released the Dyno numbers at this point for whatever reason but I was told it was very impressive. Here is a link to an instagram video they posted of it on the dyno and then a short blast on the street.

https://www.instagram.com/p/CMKqD5BHwrr/?utm_source=ig_web_copy_link

 

Rebello currently has 3 heads they are doing builds with. At the moment I'm in production on 5 more heads and three of those are spoken for. So that will put the sold units up to 13.  The lack of available HP data is troublesome but that isn't stopping sales. I think people who have the means to get one of these can see the potential based on published CFM numbers as well as the fact that it's Honda valve train. 

[DuffyMahoney]

6 hours ago, Derek said:

As it stands I have been paid for 10 cylinder heads. The only ones that are actually running and drivable is SN001 which is mine and I have over 7K miles on it, SN005 has over 10 K I think and SN010 which is in a Zcar Garage/Rebello build. Probably not to many miles on it but the word I got on that one was the owner was very happy. That car is a 3.15L I think. They haven't released the Dyno numbers at this point for whatever reason but I was told it was very impressive. Here is a link to an instagram video they posted of it on the dyno and then a short blast on the street.

https://www.instagram.com/p/CMKqD5BHwrr/?utm_source=ig_web_copy_link

 

Rebello currently has 3 heads they are doing builds with. At the moment I'm in production on 5 more heads and three of those are spoken for. So that will put the sold units up to 13.  The lack of available HP data is troublesome but that isn't stopping sales. I think people who have the means to get one of these can see the potential based on published CFM numbers as well as the fact that it's Honda valve train. 

The fact Zcar won't release data is so strange to me.  Why the hush hush?!

[Ineptitude01]

6 minutes ago, DuffyMahoney said:

The fact Zcar won't release data is so strange to me.  Why the hush hush?!

 

Given the amount of "dyno drama" that poor Rob has had to endure, my understanding is that it's now up to the owner to share information if they want it made public. For instance, two guys in the Roadster community - Will and Alvin - had a sort of "not entirely friendly" rivalry over whose car could make more power. Will runs vintage race, so original U20 hotted up by Rebello and only era-appropriate mods. Alvin runs an SR20, which is one of those controversial things in Roadster-land due to the frame cutting required to fit it.

My dumb ass accidentally got in the middle of it when I took my Roadster with the Lou Mondello "R23" stroker to ZCG for a dyno day. Since I'm friends with both Will and Alvin, I thought it would be fun to challenge both engines at the same time, y'know, "haha, what if an R16 made more power than either of your cars?".

It turns out that it was a whole can of worms, and I wish I'd never said anything. In the end, Rob was willing to plot my run against theirs on the shop computer, but on the condition that I didn't take any pictures or share the comparison. He emailed me my own dyno results to do with as I wished, but obviously I wasn't allowed to take Alvin's or Will's.

[DuffyMahoney]

2 hours ago, Ineptitude01 said:

 

Given the amount of "dyno drama" that poor Rob has had to endure, my understanding is that it's now up to the owner to share information if they want it made public. For instance, two guys in the Roadster community - Will and Alvin - had a sort of "not entirely friendly" rivalry over whose car could make more power. Will runs vintage race, so original U20 hotted up by Rebello and only era-appropriate mods. Alvin runs an SR20, which is one of those controversial things in Roadster-land due to the frame cutting required to fit it.

My dumb ass accidentally got in the middle of it when I took my Roadster with the Lou Mondello "R23" stroker to ZCG for a dyno day. Since I'm friends with both Will and Alvin, I thought it would be fun to challenge both engines at the same time, y'know, "haha, what if an R16 made more power than either of your cars?".

It turns out that it was a whole can of worms, and I wish I'd never said anything. In the end, Rob was willing to plot my run against theirs on the shop computer, but on the condition that I didn't take any pictures or share the comparison. He emailed me my own dyno results to do with as I wished, but obviously I wasn't allowed to take Alvin's or Will's.

I still think this engine deserves this data to be made public. I actually thought the engine was in Robs own car?  

[rturbo 930]

1 hour ago, DuffyMahoney said:

I still think this engine deserves this data to be made public. I actually thought the engine was in Robs own car?  

Agreed. And I really don't understand the secretiveness for anything outside of a competitive environment, which this is not. You would think he would at least tell Derek, the manufacturer of the head, what the numbers are.