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pierre2212

Nissan a14 motor reaching 100kw

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Hi Guys i am new here on this Forum from South Africa.

I am building a Nissan Champ think it is called the b140.

i am rebuilding my engine to reach an output of 100kw to the wheels.

I am going N/A for this project.  

i do have a stoker kit for the A15 motor so i was thinking swapping the A15 crank and conrods and head over to the A14 block. I do have a 278 degree split cam( freaking nasty little cam)

what else can i do to reach 100kw? still on its stock carburetor. I was also thinking about boring out to 77mm piston size

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100Kw is.... over 134 hp!!!!  Is that even possible without a turbo?

 

Well the stock carb has to go. Individual throttle bodies or motorcycle carbs.

 

Longer stroke will reduce your red line from 8k down to 7.5K although it does give you 100cc extra displacement.

 

Definitely a header of some kind on a balls to the wall build like this.

 

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i know its a lot 😄 , yeah i am thinking about going to ITB's later on tho. Will it help if i do a stroker kit and a overbore on same engine? .Would just like to know if it is possible n/a otherwise i will try some turbskies

 

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Just increasing power 50% is a formidable and formidably expensive undertaking. 100% increase is optimistic. Longer stroke will limit how high you can rev to make HP but it does increase power at below that. There are other members that race the A series an can comment on this.

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A full race A14 will achieve about 160 hp at around 9500 rpm, so 135 with a street driven A15 is not going to be realistic. Not saying ti can't be done, but you're pushing the limits of driveability.

 

I've only ever built a couple A15's, mostly A12, A12A, A14 motors, but I am wondering how on earth you would fit an A15 crank and rods in the A14. The deck height on the A15 is so much taller. Even with a custom piston, and a de-stroked crank, it seems tight. Has anyone done it?

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Can always try to fit the a15 internals into the a14. See i would want to kbow if it will be possible or should i rather safe the money and time and get me a sr20 or 4age? Maybe 100kw was a bit optimistic 🙈

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The A15 and A14 use the same block with a deck height of 204.1mm, the A14 uses a 77mm stroke with a piston pin height of 32.5mm and the A15 uses a 82mm stroke with a 30mm pin height. They both use a 76mm bore.

 

As to the original question first I will share this; my so called race motor makes 99hp at the wheels. It uses a ported GX head with 39mm flatslide carbs, 278 cam, headers with 2 inch exhaust and 11.90-1 compression. It's streetable but uses 100 octane fuel. While the motor will run at any RPM it's happiest above 4500rpm and doesn't really make power until 5500 rpm.

 

Realistically 110hp at wheels is probably the turning point. 

 

A b140 makes all of 80hp at the crank stock (55-60 at the wheels?) so getting one up to 85-90 at the wheels is a huge improvement. 

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Will it possible to use the a14 pistons on the a15 crank and condrods? Because my a15 has a deeper dish in and my a14 has a slightly dish

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On 8/2/2018 at 6:56 PM, Tom1200 said:

The A15 and A14 use the same block with a deck height of 204.1mm, the A14 uses a 77mm stroke with a piston pin height of 32.5mm and the A15 uses a 82mm stroke with a 30mm pin height. They both use a 76mm bore.

 

 

 

A14/15s use the same rod length so yes.

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Pierre you will not be able to use the A14 pistons with the A15 crank because the pistons  will be sticking up 2.5mm above the deck. Not the previously mentioned piston pin heights, due to the 5mm longer stroke of the A15 Nissan decreased the piston pin height 2.5mm. You can mill the A14 piston down of course but that would likely lead to piston failure.

 

 

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Yup the rods are the same but the stroke is longer. Should have finished my coffee before posting.

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So here are some options to get the compression up.

 

Custom pistons; this is what I did. $600 for forged JE pistons with rings.

 

The standard A15 pistons come in a 6cc and 10cc dish and the head gaskets standard have a 1.2mm crush thickness. You can get a GX head gasket with a .8 crush thickness and a Nismo one with .6 crush thickness. Both available on EBay. Bprojects is on EBay (there a Japanese company that specializes in A-series stuff for Sunny models) You could get 6cc dish pistons and the thinnest gasket, I believe that will take you to 10-1 compression or close to it.

 

Honda pistons come in 76mm with flat tops / near flat tops; I can't remember if it's the D15 or B16 but you can look it up on the Internet. They Honda piston uses the same 19mm pin as the Datsun.

 

You can use Mazda MX-5 / Miata 78mm pistons, the small end of the rods will need to bore to 20mm and the piston tops milled flat. The issue with this solution is the compression ratio may be rather high for a street car. I don't know what head you're using, they vary from 29cc to 32cc combustion chambers and you would need to use one of those online compression ratio calculators.

 

DO NOT, DO NOT mill the head to get the compression up; this causes all sorts of issues with push rod lengths and rocker arm geometry. One of my cylinder heads has had 2mm milled off it and due to that I've had to fly cut deep notches into the forged pistons as well as make shims for the rocker shaft pedestals, as well as mill some of the pedestals. I have to mix and match the modified parts to get everything correct when every I fit different cams. It was a  pain to sort, luckily I have a machinist friend who's able to make these little custom bits. It's one thing to do it for a race car but quite another for a street car. 

 

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Thought I would resurrect this topic. Since Pierre is from South Africa and others might have some input I'm wondering why we can't get parts for these old engines and transmissions here in the states. The A series Datsun engine and 60 series transmissions were being offered in new Nissan's in South Africa  only about 10 years ago and I'm sure parts are still available there but why not here???

 

Kurt

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The last A series was in the 210? about 36 years ago. We've moved on to more larger more fuel efficient lower pollution engines. There's no market for new parts.

 

No one want to buzz along at 70MPH. Cars are safer and heavier and have to pollute less. An A series just can't cut it.

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6 hours ago, datzenmike said:

The last A series was in the 210? about 36 years ago. We've moved on to more larger more fuel efficient lower pollution engines. There's no market for new parts.

 

No one want to buzz along at 70MPH. Cars are safer and heavier and have to pollute less. An A series just can't cut it.

Hey watch it pal, my little A12 motor buzzed along at 65-70MPH last weekend on an almost 800 mile round trip to a Datsun show.

 

Sometimes slow is the way to go.

 

(above to be read in sarcasm font)

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😄 I was referring to 'them' or today's driving culture. They want high speed option loaded cars that have to have air bags and ABS with power everything and back up cameras. Try cramming all that shit into a B-310 that doesn't even have EFI. If there were parts, you're would not be as unique. I agree on the parts availability though. I love my Datsun, it's like having a Hudson, Packard, Studebaker.... they just don't make them any more. Not exactly like having a Pontiac or an Oldsmobile though. 😄

 

As they get older, keeping one operational will present even more difficulties. Rule #1.... NEVER throw anything away no matter how used or broken. Rule #2 ....  constantly watch out for available parts and grab them, then Rule #1 applies.  Rule #3 learn to do your own fabrication/work/repairs. Rule #4 Be aware that a GM or Toyota part may do the same job as a Nissan one or can be modified to. When it comes to vintage car ownership anything goes to keep it on the road.... NOT like today's cars.

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I've owned a few A powered vehicles, and I agree with Mike. Though plenty of fun to drive, the buzzing does get to you after a while.

 

My A12 made 100hp, and was totally capable of keeping up with modern traffic, but it did buzz.

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I say let him do it. Sometimes people Ask for opinions and yet they are hard up already in making it happen. 

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On 10/13/2018 at 8:06 AM, datzenmike said:

😄hey get older, keeping one operational will present even more difficulties. Rule #1.... NEVER throw anything away no matter how used or broken. Rule #2 ....  constantly watch out for available parts and grab them, then Rule #1 applies.  Rule #3 learn to do your own fabrication/work/repairs. Rule #4 Be aware that a GM or Toyota part may do the same job as a Nissan one or can be modified to. When it comes to vintage car ownership anything goes to keep it on the road.... NOT like today's cars.

I follow these rules very closely and it is working out well and saves me a lot of money.

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Hey guys I didn't ask if these engines are relative today only why I can't get parts in the US while these engines were fitted new in South African "Bakkis" just 10 years ago. I like to swap them into other extinct vehicles. Namely, MG Midgets and AH Sprites. What makes them relative to those vehicles is the fact that they FIT a small rear drive vehicle and have a nice Datsun 5 speed behind them, again, designed for a REAR drive vehicle. Sure a 4AGE would be fine and has been done but try to find one of them now days and their 5 speed REAR drive transmission. Fact is that anyone wanting to drive something small, fuel efficient [my A15 powered Midget regularly exceeds 40MPG and kicks A on any BMC powered Midgets], rear drive and just fun is scr*wed now days. 

 

So I hope others will ask the same question, perhaps of Nissan. WHY can't we get parts for these vehicles when I'm sure they can be had in South Africa.

 

Kurt   

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We got the Z18 for part of 73 and all of '74 year it was used on the Australian 720 in the 80s. Different parts of the world got different parts and engines and sometimes for longer. Shipping something like a 5 speed from SA wold be a nightmare without relatives there.

 

On 10/18/2018 at 12:02 PM, captain720 said:

I follow these rules very closely and it is working out well and saves me a lot of money.

 

Many years ago I grabbed a set of '84 Maxima struts. (free) Had no need for them as I had had a 620 for years. Figured someone might want them..... and 6 years later I put them on my 710 I didn't plan on ever having. 

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Right Mike. Its my understanding that SA is sort of a failed state and any financial dealings there are risky. Don't have a relative there so I am out of luck.

 

Still can't figure out why I can't get the parts I need from Nissan when I'm sure they can!!! Maybe just a line on a reputable dealer in SA. I buy parts from England regularly and they often arrive quicker and with comparable freight to domestic ordered parts. Can't see that freight cost would be a factor.

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I few years ago I needed some non US spec Toyota parts, and Toyota USA, though capable of getting them, has a policy against that. So I simply googled Toyota UK and literally did the blind pointer on a map thing and picked. Why the UK? Because they speak English. I don't speak Japanese, though I tried through an online interpreter to not much success.

 

I do business with a couple Australian companies, and the transactions are seamless and simple. Could these Datsun (Nissan) parts be sourced out of Australia?

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