Jump to content

1981 Datsun 210 A15 Turbo Build Questions


floyd17

Recommended Posts

Hey guys, been a while since I've been on here, but I've got plans for the car back in gear and a lot of parts. Planning to build my A15 with an h89 head (question: should I get the H89's cam as well?), dual DCOE 40's (which I have), and a Mercedes twin turbo (which I also have), I also have to track down a h190, or do you guys know how well a ford 8.8 rear end from a mustang would fit under the car? Also considering different year pistons? I've heard the pistons for the A76 head have a shallower dish than for the economy head. What do you guys think? My goal is to run in the solid 13's in the 1/4, and be fairly decent around a track. As always, pics to follow soon! She's in the air now, just rebuilt the transmission.

Link to comment
  • Replies 16
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Planning to build my A15 with an h89 head (question: should I get the H89's cam as well?)

 

Cams are cut based on engine size more than head designation. For the most part all the of the A14/A15 cams are identical. 

 

And turbos don't care much for big cams. 

 

 

dual DCOE 40's (which I have), and a Mercedes twin turbo (which I also have

 

One moderately sized turbo and one carb would be better. Blow-through or draw through? If draw through, one big SU or one DCOE would be ideal.

 

Proper headwork will be a lot more important that head selection or cam selection. You will need HUGE ports to flow that much air/fuel. 

 

 

I also have to track down a h190, or do you guys know how well a ford 8.8 rear end from a mustang would fit under the car? 

 

You will need flared fenders and high positive offset wheels. That's a very wide axle for this car. 

 

Ideally, get one from an Explorer. That gets you disc brakes and an LSD, then have it narrowed it a bit to fit. 

 

 

My goal is to run in the solid 13's in the 1/4

 

I would adjust your goals and shoot for mid-to-low 14s. 

 

Making that much power from an A-series will be extremely difficult, and you will be breaking transmissions on a very regular basis. 

 

 

Also considering different year pistons? I've heard the pistons for the A76 head have a shallower dish than for the economy head. 

 

You don't want shallower dish for a turbo. To make the kind of power you're asking for, you'll need a fairly low compression, around 8:1 max. 

 

 

 

The old man disclaimer: To make this kind of power with carbs and an A-series will be very difficult, bordering on impossible. If you're intent on using an A-series, be thinking about fuel injection, not carbs.

 

The second old man disclaimer: You're about to spend several thousands of dollars and possibly hundreds of hours to basically make less power than a mild SR20DET would. 

 

 

 

And as I say a lot, "because you have it" is the worst possible reason to do anything.   ^_^

  • Like 2
Link to comment

Cams are cut based on engine size more than head designation. For the most part all the of the A14/A15 cams are identical.

 

And turbos don't care much for big cams.

 

 

 

One moderately sized turbo and one carb would be better. Blow-through or draw through? If draw through, one big SU or one DCOE would be ideal.

 

Proper headwork will be a lot more important that head selection or cam selection. You will need HUGE ports to flow that much air/fuel.

 

 

 

You will need flared fenders and high positive offset wheels. That's a very wide axle for this car.

 

Ideally, get one from an Explorer. That gets you disc brakes and an LSD, then have it narrowed it a bit to fit.

 

 

 

I would adjust your goals and shoot for mid-to-low 14s.

 

Making that much power from an A-series will be extremely difficult, and you will be breaking transmissions on a very regular basis.

 

 

 

You don't want shallower dish for a turbo. To make the kind of power you're asking for, you'll need a fairly low compression, around 8:1 max.

 

 

 

The old man disclaimer: To make this kind of power with carbs and an A-series will be very difficult, bordering on impossible. If you're intent on using an A-series, be thinking about fuel injection, not carbs.

 

The second old man disclaimer: You're about to spend several thousands of dollars and possibly hundreds of hours to basically make less power than a mild SR20DET would.

 

 

 

And as I say a lot, "because you have it" is the worst possible reason to do anything. ^_^

 

Thanks for your VERY thorough and informative response. That helps a ton. I really don't think I'm gonna have to spend that much money on it, because most of the work I'll have left to do is fabrication work, being that I have lots of parts laying around. And as far as fabrication I have recourses to get done cheaply or myself.

 

On the note of EFI, could I rip the computer, sensors,and throttle body off of another 1.5l motor (maybe a Toyota or Nissan) retrofit them on the A motor and run efi that way?

 

 

Planning a draw thru setup as far as the turbo.

 

Again, thanks. Pics shorty :)

Link to comment

If you are really serious, this is going to cost you money and more research.  I think you better do your research first. You can't run an intercooler with a draw through set up. You're going to need forged pistons if expecting to boost over 10 PSI. Stock pistons are good for about 8 pounds of boost. I would hold off on the H-190 or 8.8 because the engine won't last long enough to matter.

Link to comment

If you are really serious, this is going to cost you money and more research. I think you better do your research first. You can't run an intercooler with a draw through set up. You're going to need forged pistons if expecting to boost over 10 PSI. Stock pistons are good for about 8 pounds of boost. I would hold off on the H-190 or 8.8 because the engine won't last long enough to matter.

That's why I came here, so I'd know what I'm getting into, and have a starting point for my research. I may do a blow thru, which one is likely to make More power? Draw thru is easier to tune with carburetors right? And with efi, either draw thru or blow thru is equally difficult/easy?

Link to comment

Theoretically 50% increase in power. Probably over 100 hp. You can safely use stock hyper-eutectic pistons then, but you really do need a good ignition retard.  If blow through, you will need a variable pressure fuel pump to push fuel into the carb against the boost and you can use an inter cooler although for 8 PSI you won't gain all that much. EFI isn't a simple as that. These systems are simple and can't supply much more than stock displacement requirements. A 1.5 liter at 8 PSI will 'look' like a 2.3 liter engine for fuel needs.   

Link to comment

Theoretically 50% increase in power. Probably over 100 hp. You can safely use stock hyper-eutectic pistons then, but you really do need a good ignition retard. If blow through, you will need a variable pressure fuel pump to push fuel into the carb against the boost and you can use an inter cooler although for 8 PSI you won't gain all that much. EFI isn't a simple as that. These systems are simple and can't supply much more than stock displacement requirements. A 1.5 liter at 8 PSI will 'look' like a 2.3 liter engine for fuel needs.

So as far as getting enough fuel to efi, I need a strong fuel pump, and injector(s) able to push enough fuel so that the mass air flow sensor can tell the CPU to dump

More gas as the RPM's increase and the turbo spools?? Or is that not a correct assumption?

Link to comment

Pretty sure the EFI delivers a little more than what the engine will ever need at full RPM power. A turbo will ram like 50% or more air in, a condition that the maker would never assume it would ever do and build for. For this you would need your own system that you can program.... like Mega Squirt.

Link to comment

I'm expecting 7-8 pounds of boost.

 

Then expect mid-16s. Maybe lower if you put the car on a fairly serious diet. To go as fast as you want, you're looking at 20+ pounds of boost. 

 

Side note: An A15 on 7 pounds of boost will be fairly comparable to an L20b with a mild cam and some SUs. And with some judicious junkyard scrounging, that's a bolt-in swap. 

Link to comment

I really don't think I'm gonna have to spend that much money on it, because most of the work I'll have left to do is fabrication work

 

I was mostly talking about head work. I have over $1k in my head with just port work, (maybe $3k+ in the whole engine) and I'd be amazed if it makes over 110hp. That's without a turbo...

 

gallery_102_398_1483045161_34314.jpg

 

 

 

 

Project car math: It takes twice as much money and take three times as long as whatever you have budgeted.   ^_^

Link to comment

Then there's the law of diminishing returns. First 10 hp cost $100, next 10 costs $350, the next $1,200 the next $4,000. If you just have to have an A series engine you are going to have to rev it up. Theoretically a doubling of RPM doubles the HP. To keep this together you are going to have to add strength and that ain't cheap either. Or get a larger displacement engine that makes more power at lower speeds.

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.