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how to free up hp on stock a14


josh_t

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well since its seemingly so hard to get 20 horsepower, i should focus more on getting the 80 that i have to the ground. does anybody have an approximate price that i could find a good FS5W63a for? i can do the wiring for the interlock switch and i can get a clutch master cylinder new for a decent price. i would need a clutch pedal and a manual brake pedal since the auto pedal is wider. i have read that i can use the original drive shaft. is this correct? and datsun1200 says the starters differ from auto to manual. and is this true to all a14's where you have to grind the lip off of the automatic crank to put the manual flywheel on? http://datsun1200.com/modules/mediawiki/index.php?title=Manual_transmission_conversion scroll down you will see it

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imassuming that you dont want to cause youve ignored everyone thats suggested it but its true, if you want performance, swap a different motor in, will probably even be cheaper

 

 

I agree! I have a 81 210, swapped in the 5 speed and got the webber. Yes, you will feel a difference. What I should have done is just found a KA24E on CL and swapped that in there. I don't know about your year but for the tranny swap you'll need the pedal assembly out of a manual car, master and slave cylinders, flywheel, and manual drive shaft. I don't know about the starter issue, mine was the same. Good luck.

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That will take around $2500 worth of performance mods to get an A14 or A15 to 100 HP. The stock heads are only good for 85 HP.

 

Or just stick an 110HP L20B in it, no fabrication required. Fits in the B210 tunnel. Uses the stock B210 automatic driveshaft.

 

Yes if you fit lower gears in the back, that will improve accleration across the board. The only problem with that is 3.9 gears are the lowest they used in USA. NISMO used to sell lower gears, you might find them on Craigslist or eBay from time to time. I have 4.11 and it makes a big difference compared to 3.9. NISMO had 4.8 and 4.6 and 4.3 gears.

 

 

imassuming that you dont want to cause youve ignored everyone thats suggested it but its true, if you want performance, swap a different motor in, will probably even be cheaper

 

 

I agree! I have a 81 210, swapped in the 5 speed and got the webber. Yes, you will feel a difference. What I should have done is just found a KA24E on CL and swapped that in there. I don't know about your year but for the tranny swap you'll need the pedal assembly out of a manual car, master and slave cylinders, flywheel, and manual drive shaft. I don't know about the starter issue, mine was the same. Good luck.

Listen to these guys^^^. The A motor is great at what it was designed for. They are rugged, reliable, and economical. Cubic dollars is not always a great substitute for cubic inches. You will be money ahead to just do a modern engine swap (or even an L20b) to get the end result you seek. There are several well documented swaps that can be done on a relatively low budget. You can bore, stroke, squeeze, boost and inject an A14 but it will be very expensive and likely disappointing in the end. You will probably find more enjoyment in a car that starts every time, idles smoothly, gets reasonable MPG on regular gas, and doesn't require constant tinkering. It's your car and you can do whatever you wish. Most of us have been there and our experience might save you some headaches and expense. Keep us posted.

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i would love a ka or a vg in my car but i dont have the money or tools and i live in a subdivision and can't use the garage so that will get me in trouble. but like the original post stated i was looking for free or cheap ways to get a few horsepower. maybe its not gonna be the number i'm looking for but i want some suggestions on jet sizes so i can at least get a little better throttle response. i know somebody has to have re jetted a hitachi before. jets are cheap. and is there anything i can do to the secondary vacuum system to get i little more out of this carb. Don't tell me what motor i can put in it because i know what motors i want in it and none of them are an option at the moment and neither is swapping a 4 or a 5 speed into it.

 

Edit: if i could find a 4-speed around here for 60 that would be fantastic. but i still need to know about the drive shaft situation. and i haven't the slightest clue where to find a junkyard around ATL.

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Stock A12 carb is reported to be an upgrade. ggzilla can likely confirm or deny this. He is the man when it comes to A series knowledge.

 

i read in my chilton manual that they had bigger jets. thats exactly what i'm lookin for. now if i knew somebody who put a weber on their a12 i could get the hitachi most likely for free.

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i have a 76 b210 with an a14. it is an automatic as well. i was wondering what i can do to free up some horsepower for free or cheap. i already put a free flowing exhaust on it, advanced the timing 5 degrees, and all the emissions systems are off of it. i wasnt the one who removed the emissions parts though. is there anything i can do to get a few more horses with the dch 306 carb?

 

 

 

 

i would love a ka or a vg in my car but i dont have the money or tools and i live in a subdivision and can't use the garage so that will get me in trouble. but like the original post stated i was looking for free or cheap ways to get a few horsepower. maybe its not gonna be the number i'm looking for but i want some suggestions on jet sizes so i can at least get a little better throttle response. i know somebody has to have re jetted a hitachi before. jets are cheap. and is there anything i can do to the secondary vacuum system to get i little more out of this carb. Don't tell me what motor i can put in it because i know what motors i want in it and none of them are an option at the moment and neither is swapping a 4 or a 5 speed into it.

 

Edit: if i could find a 4-speed around here for 60 that would be fantastic. but i still need to know about the drive shaft situation. and i haven't the slightest clue where to find a junkyard around ATL.

 

No money tools or space means you had better stick with a good tune up and live with it. If this is your daily driver switching to a standard is a major operation in itself and again " no tools or space" is only making plans that much harder. The easiest way to swap in a standard is to have a complete parts car right there and switch the parts over. Here's some things needed or to consider:

 

Clutch and brake peddles including the clutch peddle pushrod, all springs, nuts ,bolts, clips, switches. Clutch master (new is best) Master to slave hard and flex line to clutch slave. Clutch slave (new is best) Slave pushrod. 4 or 5 speed transmission... must include shifter, knob, rubber dust boot, clutch arm and attaching clip and release bearing collar (if these do not come with the tranny you must find them also). A pilot bushing (new) installed in the end of the crankshaft. A flywheel (may need resurfacing).A clutch disc and pressure plate (new is preferable here) A matching release bearing for the release bearing collar (definitely get a new one, often the correct collar is included with the clutch set) Transmission mount to body. Sometimes an auto will work or can be reversed and used but this needs some research. Drive shaft. You need one that fits your car/transmission choice or yours shortened and balanced. This will get you started and I may have missed something, but even one thing missing could prevent this swap from being completed.

 

Have you thought of renting garage space from a neighbor? Trade for cutting lawn, yard maintenance???

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well there is the slight chance that i could get away with swapping the tranny here since i did just do all that work on my diff the beginning of this week. that made a big mess and nobody even gave me a dirty glance. but it still would be a huge task. i will probably wait until i'm attending uti mooresville to do a tranny swap. i would have no shortage of tools and i would have 20% off at the on campus napa store. plus the lovely added benefit of a lift. that would save me some cramping.

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A KA swap can be done for as little as $30 and a lot of hard work. It is a total bolt-in if you find the right parts. The only fab needed is simple mount plate driling.

 

 

some suggestions on jet sizes so i can at least get a little better throttle response. i know somebody has to have re jetted a hitachi before. jets are cheap. and is there anything i can do to the secondary vacuum system

 

I haven't heard of anyone who has re-jetted a Hitachi, although it should help pick up some throttle response. This is because the Hitachi is small, smaller than the engine it is on. It is undersized for good throttle response and maximum fuel economy. So everyondy sticks a larger carb. Sometimes you can find a Weber 32/36 for $50, such as at Pick-N-Pull or from a buddy who's selling one.

 

Don't use an A12 carburetor. Well, if you can find a 1973 carb in good shape it will do. The A12 carb is slightly smaller. The 1976-on carbs are jetted very lean for emissions, so putting fatter jets in it will work work just as well (assuming the carb is not worn out).

 

Hitachis don't have vacuum secondary except 1981-1982 models.

 

Once you swap out the auto and swap in a 4-speed, it's going to feel like you doubled the HP.

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i was thinking it did have a later carb swapped in there since the alternator was from an 81. there is a time stamp on the side of the carb with a 1 in the middle. so i have an 81 carb, alternator, and i'm hoping thats it

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Just go get yourself a 310 H89 head with matching intake/exhause manifold, put on a Weber 32/36 and get the matchbox distrubuter and call it good. Parts are easy and cheap to find. Makes a world of difference and keeps reliability if your good at carb tuning.

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What is the code printed on the carburetor? It should say DCH306-xx. What is the xx?

 

5919.jpg

 

my carb doesnt look like that. i looked at some pics of a dcr 306 and thats what it is. i'm kinda not happy about it since 76 was the year with the most power. 81 was a lot lower even considering it was an a15

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i know. but how easy is it to swap a carb vs a transmission? plus i know a guy who races dirt track cars up in tennessee and they have a pony car class which is 99% of the time a 2.3 ford mustang stripped down with a roll cage and 350+ hp the 2.3 cam stock with a holley 5200 which is a weber 32/36 dgv licensed to holley. all the parts are weber. so i can probably get one for free from him since he knows people.

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81 was a lot lower even considering it was an a15

Makers used to quote engine hp numbers, even going so far as to remove the alt, flywheel, water and fuel pumps and using special gas to boost the numbers. They were eventually forced to use rear wheel hp numbers which includes all frictional and accessory losses and is better for comparison. This amounts to about 18% differences.

 

 

 

Swapping to a manual will give you more performance than all those parts will.

 

 

Yes

 

i know. but how easy is it to swap a carb vs a transmission? plus i know a guy who races dirt track cars up in tennessee and they have a pony car class which is 99% of the time a 2.3 ford mustang stripped down with a roll cage and 350+ hp the 2.3 cam stock with a holley 5200 which is a weber 32/36 dgv licensed to holley. all the parts are weber. so i can probably get one for free from him since he knows people.

 

Carb isn't going to make that much without a cam change

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i do know that they changed to rear wheel and net power instead of gross flywheel power but that changed after 71 in the us. if you look at the power from 76 to 82 there is a slow decline of about 2 to 3 horsepower per year thats not an 18% change. so they did lose power gradually because of emissions and economy concerns. i know i need a manual but unless you are going to pay for the parts and give me a place to work on it then it isnt happening. Realistically, i can do a carb change because that carb is very tuneable and all i would have to do is buy or make an adapter plate. And i cant do a motor swap for the same reasons as the tranny swap. I never claimed massive gains from the carb swap anyhow. It would be more of a reliability upgrade since all the trouble i have with this engine is carb related.

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They have not changed to rear wheel HP ratings. It is still at the flywheel for every major car manufacturer.

 

Like Mike says, they used to remove things from the engine, then rate the gross HP. Since 1971 or so they have to leave the engine as-installed and rate it (net HP). So it is more accurate. However it is up to the manufacturer to rate it, so sometimes they fudge higher or lower.

 

The reason 1981 A15 is lower HP is because they tuned it for mid-range HP. It uses a cylinder head with medium size ports. It is in fact the same head they fitted to A12 in 1981. So a carb and cam won't restore it to 1980 high-RPM power levels.

 

A Holley 5200 is a licensed design but does not use Weber parts. The jets for example are different. But it is a good carburetor, pretty much the same as the weber 32/36.

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They have not changed to rear wheel HP ratings. It is still at the flywheel for every major car manufacturer.

 

Like Mike says, they used to remove things from the engine, then rate the gross HP. Since 1971 or so they have to leave the engine as-installed and rate it (net HP). So it is more accurate. However it is up to the manufacturer to rate it, so sometimes they fudge higher or lower.

 

The reason 1981 A15 is lower HP is because they tuned it for mid-range HP. It uses a cylinder head with medium size ports. It is in fact the same head they fitted to A12 in 1981. So a carb and cam won't restore it to 1980 high-RPM power levels.

 

A Holley 5200 is a licensed design but does not use Weber parts. The jets for example are different. But it is a good carburetor, pretty much the same as the weber 32/36.

 

well i have an h72 head which was a regular size oval port compared to the h95 which was small oval port head used on all 81-82 usa engines regardless of size. They also changed the carb from a dch to a dcr for those years, so my guess is that the carb is mismatched and probably degrading my performance to a certain degree.

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I doubt that. The carbs have similar jetting. The 1981-1982 carbs is more precise than the earlier ones. However it is common for 10 year old carbs (let alone 30 year old) to have broken diagphragms and leaking throttle shafts. So changing the carb may make a difference, but not because it is the "wrong" carb.

 

I'm running a 1980 A14 carb on my 1972 A12. It is leaner, but runs better than the worn-out A12 carb it replaced.

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I doubt that. The carbs have similar jetting. The 1981-1982 carbs is more precise than the earlier ones. However it is common for 10 year old carbs (let alone 30 year old) to have broken diagphragms and leaking throttle shafts. So changing the carb may make a difference, but not because it is the "wrong" carb.

 

I'm running a 1980 A14 carb on my 1972 A12. It is leaner, but runs better than the worn-out A12 carb it replaced.

 

i have never had this pos carb running properly and i have rebuilt and cleaned many carbs successfully. it is mosty due to a cruddy gas tank making any gas i put in it turn brown and it smells awful. i have cleaned it out twice. i tried using an external tank from a small engine so i know i'm getting clean gas but it has never ran "just right" IMO. maybe it is worn throttle shafts or leaky gaskets. i have recently cleaned out the gas tank with left over gas and a half gallon of mineral spirits and pea gravel. it did remove a lot of small chips of varnish and a small amount of rust. and there is a really bad coating job that is peeling of but 90% of it is out of the tank now. i havent put any gas in it yet since i dont want to waste my time if it is still nasty in there.

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