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3.1l 280zx..


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Guest Anonymous

I wouldn't bother. It'll be more power, but still not very much. And it will be VERY expensive. I'd drop in a 280 turbo drivetrain. Bolts right up, just a few electrical connections and you're good to go. That'll be the same or more power as a fancy stroker engine, but it will be cheaper and easier.

 

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Morgan

http://z31.com/~morgan/s30

http://carfiche.com

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I don't have a stroker, but I can pass on the info and general consensus I've heard from most of the people that do.

 

Going 2.8 -> 3.1 might net you 15hp and 15lbs/ft of torque. Ask yourself if you are willing to spend $2000? for that increase.

 

My advice is to go with a hot 2.8 setup. Take that $2000 you'd spend on stroking, and put it into a set of triples, and a port and polish. (coupled with the cam you were talking about) Add some headers and a 2.5" exhaust and you can probably see high 12 second 1/4 miles with everything else taken care of. (slicks, soft rear suspension, etc) I know of guys running hot 2.8's that run 12.2 seconds.

 

Honestly I think the money for the stroker is better spent on other upgrades. If you want power over 300hp do yourself a favor and go with a V8 or turbo setup... an NA 2.8 with over 300hp will probably cost you $15,000. (just a guess) And it will not be streetable at all!

 

Hope this helps a bit.

 

 

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"THE STREETS WILL FLOW WITH THE OIL OF THE NON-BELIEVERS"

 

Drax240z

1972 240z - L28TURBO transplant on the way!

http://members.xoom.com/r_lewis/datsun.html

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Guest Anonymous

what site does a good job of listing everyhing involved in beefing up the stock 2.8 engine? i dont want to switch to carbs because i love my injectors so much.

 

i talked to Motorports and they said the 3.1 would produce 300hp easily. but everyone else ive talked to said it would produce very little power, why is that? bigger pistons, crank, etc.. would make me think, more power.

 

im very interested in a cheap build up, but the 3.1 looked like the best way to go. other routs will be great! thanks.

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Motorsport actually told you that what liars . Although it may beat some 300hp cars it will put out 210-220max at the wheels if build buy a good shop . You will get a jump in HP from the kit, go from about 130hp at wheels to 190hp at wheels with the kit . I am partial to the 2.8 turbo, but the V8 option can't be ignored .

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Guest Anonymous

No way it'll make 300hp 'easily' 200 would be easy probably though. Get a 280 turbo drivetrain. Cheap and easy and fast.

Beefing up a l28 is a losing proposition if you want major power. If you want to buy an already beefed up l28 I just happen to have one! See here for details. It'll run you about the same as the stroker kit will.

Also be aware that you can assemble the parts used in the stroker kit from junkyards for MUCH less money. The hardest part to find is the ld28 crank(Diesel l28 engine).

 

 

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Morgan

http://z31.com/~morgan/s30

http://carfiche.com

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True assembling your own kit will save you cash. LD28 cranks aren't hard to find if you are willing to get them shipped to you. Check zcar.com's classifieds, there is almost always one for sale in there.

 

If you are really stuck on efi, then find yourself a L28turbo engine in good shape and swap it in. No fabrication necessary... (hehe, unless you do what most people do and install a ton of other stuff at the same time...)

 

As for websites with modifications, its hard to beat Bryan Little's site. http://www.mindspring.com/~blittl/ZGarage.html

 

Good luck!

 

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"THE STREETS WILL FLOW WITH THE OIL OF THE NON-BELIEVERS"

 

Drax240z

1972 240z - L28TURBO transplant on the way!

http://members.xoom.com/r_lewis/datsun.html

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Guest Anonymous

hi all, ive been looking at the option of turning my 2.8 into a 3.1l with the help of the Motorports 3.1l conversion kit, that would also involve a mild cam [3k to 6.5k] and some other parts to keep it healthy.

 

my queastions are:

how reliable will this be? i want to be able to take it out on the weekends and race it, i want it to be almost as reliable as a daily driver.

 

will it be enough power? how much? + supercharger ?

 

can i get smaller pistons so its not a full 3.1 but more like a 3.0? anything to make it more relable.

 

 

thanks very much.

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I'm biased - I really think the V8 is the way to go but... I've also driven a turbo 280ZX with nearly no mods...

 

If you're NOT interested in the V8 then yeah certainly go for the turbo 2.8. If that's still not enough power after you've done the exhaust, played with the turbo, and tweaked the computer then consider upping the displacement. I'm not sure what hi PSI 280 turbos are running but the drive I did in a wounded one hit about 12lbs and it felt pretty nice. Heck, maybe you could even swipe the motor out of an early turbo 300ZX :-) The cost of doing a stroker motor right off is probably not going to yield the performance you want as everyone else has said. Maybe try to find one already built being bought instead of doing it yourself - zcar.com has them up for sale once in awhile.

 

Forced induction is the best way to find power that I've seen so far short of NOS. The rush when boost hits is addictive and it makes all sorts of really nice sounds...

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Engines are essentially air pumps. Fuel and air mix to give you power. The more fuel and air you can get into the engine the more power you make. Having more displacement usually means the engine is capable of ingesting more airfuel - thus more power.

 

V8s don't make massive power via boring anymore than your motor will make much more with a 10% increase in displacement. A 350 stroked and bored to 383cubes makes more torque, a little more power all things equal, and usually won't rev as high. However to build a 383 doesn't cost much more than a good 350 so I'll take the extra power while I'm at it.

 

So, you want lot's of power. You're going to have to get that air in there some kind of way. Wild cams and massive compression will do it but driveability will go away, so will MPG, forget emissions, and maybe even have to buy race gas. Yuck!

 

So, MY favorite way of getting more power out of a mild engine is to force feed it. Your friend's turbo was an automatic and probably running stock boost - it was slow for a reason. Ever take a ride in a hopped up Buick GN? Can you say faster than a 'vette and carrying MUCH more weight? From 231 cubes! 14lbs of boost on an engine means it's eating DOUBLE the air that it possibly could naturally aspirated. It'll do this with a mild cam, normal compression, and decent driveability! There's lot's of ways of force feeding a motor, including NOS, but with the Z there's tons of turbo motors sitting in boneyards for cheap - not taking advantage of that is crazy! If an early 300ZX turbo motor would drop in then that's what I'd do else go for a 2.8 turbo.

 

Pick your poison - high strung and finicky or boosted. Not enough power? Turn up the boost - so long as you've got fuel to go with it you're in business. Most folks who've lived with high powered turbo cars love them, you really ought to try driving one.

 

As for V8s being heavy and fat - wake up. A V8 Z done correctly will have as good if not better weight bias, handle as good, and make 400+hp without breathing hard. Take that 14lbs of boost and cram it into a 350+ cube V8 and compare the power output to doing the same to a smaller motor. Guess which one is probably making more power and torque? It's all math and it's all about air and fuel - both engines live by the same physics despite what the Honda guys seem to think (smile).

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Guest Anonymous

well, ive thought about the 300zx conversion because i have a 300zx na engine and tranny but i looked at the stock specs and its close to the same as the stock 280zx engine, and everyone else said it was a waste of money.. that left me 1 option, rebuild my motor. i dont want turbo, i personaly dont like turbos and my friends 280zx turbo automatic was slower then piss.

 

1) i want to rebuild my engine to be the fasest i can get it, without adding a turbo, but keeping it where i could add a turbocharger later.

 

2) i dont want to buy something premade or anything with an AMERICAN engine inside of it, nissans are fast and dont need some big bulky v8 inside it smile.gif

 

3) heres the question.. how do i build my engine to be the fastest it can? if the 3.1 upgrade will only give me 40more HP ? then what will yeild about 250ish HP? im still puzzled why overboring the engine and beefing everyhting to make it a 3.1 will only produce very little horsepower. last i heard that v8's that get overbord to be huge always produce lots more power. but im not mechanic and dont know these things..

 

what can i do to make my na produce alot of power? keep in mind i dont want CARBS, and it has to be done to my stock 280zx engine, i can change anything.. money is almost no option.

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Guest Anonymous

The stock 280zx non turbo fuel system won't provide enough fuel for anywhere close to 250 horsepower. You'll be doing good to get just barely over 200hp from it.

You'll have to get carbs or do something about the injection(expensive!).

You need to decide if you're gonna put a turbo or not on it before you build it. You can't just slap a turbo on later and expect good results if you built the engine to be used without a turbo.

 

 

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Morgan

http://z31.com/~morgan/s30

http://carfiche.com

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Morgan is bang on. You have to decide what you want now. Adding a turbo later to en engine designed for a non-turbo application really isn't the best/most reliable way to do it.

 

As for your displacement question, look at it this way. You have a 2800cc engine and you add 300cc's making it 3100cc's. You've increased the displacement by around 10.7%... a 50% increase in power from that with no other changes isn't going to happen.

 

You want EFI, understood. About the best thing you can do will be to open up the intake and exhaust as much as you can, and get something to add more fuel. (bigger injectors, adjustable pressure regulator)

 

I'd go with a 60mm TB, get a turbo afm, or a early 80's BMW 530i afm (swap the guts with the one you have, the beauty of these are that the bore is way bigger) Headers, 2.5" exhaust, more fuel pressure, turbo injectors. Throw in a hotter cam... that's about it, oh, port and polish too. Will you see 250hp? I can't really say...

 

Remember one other way to get your car to feel like it has more power, lighten it!! Don't underestimate the effect of removing 100lbs of dead weight. (the driver! LOL, just kidding)

 

Good luck.

 

 

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"THE STREETS WILL FLOW WITH THE OIL OF THE NON-BELIEVERS"

 

Drax240z

1972 240z - L28TURBO transplant on the way!

http://members.xoom.com/r_lewis/datsun.html

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If you are really intrested about a 3.1 and want big HP talk to Hoover he is selling a Rebello 3.1 . I am pretty sure this one is et up for a turbo application . With the right turbo and engine managment 450-500hp at the flywheel can be obtained . There are a rare few that can push 250 hp out of a 3.0l, half of those are not street drivable . A turbo 2.8 pushing 250hp will be way better on the street than a 3.1l pushing 250hp .

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First, Let me welcome you to HYBRIDZ.Org, home of the Datsun ALTERNATE Powertrain swaps....GET My drift? Hope so...

 

If you don't want to put a BULKY V8 in your car, thats fine... However, I'd recommend doing LOTS of research before you spend any money on a L series stroker.. the guys here on this site are 100% correct. Force feed your motor and be happy. I did manage to get close to 250HP out of a non asperated L6 with an aftermarket set of injectors, custom regulator and a Hi Po pump and custom TB. However, strokers are another matter. They are way to expensive and not much bang for the buck... Turbo it and you will be much happier... As for getting enough power out of a Datsun power plant to make you happy... I have done tons of research on that as well... You can make a safe 400HP out of a turbo L series motor if you do the bottom end right, but getting into the 500HP range is where you will hit the wall as far as breaking things in the bottom end without getting seriously expensive. What do you consider fast or enough?

 

Don't know where you live, but my car (Until I took it off the road Friday night) just recently hit 155mph at less than 3800 rpms and was rock solid, brakes very well and will sling you out of the passenger side window if you don't have a seatbelt on... I have atleast one member here who can attest to how fast and how well balanced a "Bulky" v8 can be... The next natural question would be "Have you even ridden in a V8 converted Z?" But I digress....

 

Welcome..

 

Mike

 

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"I will not be a spectator in the sport of life!"

mjk

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Guest Anonymous

Yes i have ridden in a v8 powered 240z and yes it is fast.. i do enjoy the v8 swaps but do not want one for my car [never the less its what most people recomend]. i was hoping to be able to build up my 2.8l to a good amount of power..

 

do you have part #'s for the injectors and other mods youve made? i realy liked the idea of a "kit" like the 3.1 from MS because it usualy includes everything you need to get the job done, ive never seen anything like that for the 280zx so its been hard for me to find what mods i should perform.

 

i also dont want a turbo, like i said i dont want the turbo lag.. and untill the supercharger kit that someone posted about is made it looks like im going n/a .

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If you have a stock engine as it is now, why not start small and work from there? You have flat top pistons and a P79 or P90 head on your engine now... Find an N42 in good shape, and swap it on. Run only 92+ octane and get it in tune, and you're on the road to more power. Most of the high performance 2.8's I've seen use this combo.

 

As for a kit, you're really better off to make your own, since then you will know exactly what is going into it.

 

 

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"THE STREETS WILL FLOW WITH THE OIL OF THE NON-BELIEVERS"

 

Drax240z

1972 240z - L28TURBO transplant on the way!

http://members.xoom.com/r_lewis/datsun.html

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euro280zx, Well you have an ear full, or should I say eyefull of information and opinions. Everyone here will vary on what makes a perfect HybridZ. The main focus isn't always what makes the most hp, but to improve peformance in any area from the stock platform. Beware of any manufacture/seller's claim to big hp. Big figures will make them more $$. I'd say some of our experienced 6 cylinder Z builders have given more realistic figures for obtainable hp. Ask yourself what is going to suit your needs, how it will be driven, how tempermental a powerplant you want. Generally the higher the hp with small displacement, the more difficult and streetable they become. High compression, and big cams only work with good gas and very limited high rpms. You've stated your desire to keep the base engine and fuel injection. You prefer foriegn to domestic powerplants. Sounds like you know pretty well know what makes you happy. Keep researching and listen to those that have been there. I've seen a early Z with a turbo and nitrous hit over 132mph in the quarter! I'm sure it took a lot of cash, but I can only think he was smiling as big as the rest of us.

JS

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Euro, as Mike stated, this site is the place to yak about alternatives and if a 3.1L is what you want, then go for it.

 

HOWEVER, I need to throw in my $.02, FWIW. Before you make any decisions, you must have goals. How will the car be used? How fast/quick? How much hp/torque is it going to take? What is it going to cost? Do not shell out $$$ and discover later it is not enough.

 

You made a couple of statements that obviously did not come from first-hand knowledge. The uninformed continue to equate engine displacement with physical size. Because a 5.7L V-8 is more than twice the displacement of a 2.8L L-6 does not make it bulkier. If by bulk you mean size, then that is dead wrong. There is a motorcycle that I am beginning to see more of on the streets of FL called "The Boss Hog". It is powered by a SBC and it just continues to amaze me how really compact an SBC is. If by bulky you mean heavier, that is correct but easily offset by it being placed lower in the chassis and BEHIND the front wheels of Z. The result is equal or better F/R weight distribution than with the L-6.

 

As for turbo lag, I wont get into a long dissertation. The 2 primary reasons people have turbo lag are: the wrong size turbo, not unlike an NA engine with a "top-end" cam and long gering and (dont laugh) bad exhaust leaks before the turbo. Turbo lag is an old wives tale that is slowly dying out as evidenced by the increasing number of V-8s that are dropping superchargers and going to a properly configured turbo setup.

 

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Scottie

71 240GN-Z

http://www.mindspring.com/~vscott911/gnz.html

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OK, lets get down to business, I think Euro280zx knows where we all stand on being touchie/ feelie about our respective builds..

 

Scottie makes a real good point. Make a plan for your car and stick to it. Had I gone the route I currently have, instead of changing mid stream so many times in the past, well I would have been much happier personaly. However, since you want to keep it all L6 Nissan, and you recognize the limitations of your powerplant (Not to say you won't be able to get serious HP out of a L6, You can.. just not cheap..) lets talk about what you plan to do with the car... Do you plan to Autocross, lap days on a road course, quarter mile duty, or just running around town spanking hondas? What are your intentions for the car... Now, if you have flat top pistns and you have a P79 or P90 mechanical head, I'd not get rid of it. They flow better than the N42. I Would however plan to shave that P90/ P79 head, shim the cam towers, and put the right cam in, get the right custom fuel rail and injectors, adjustable regulator, and upgrade the ignition system. Also, and in my opinion this is key to any performance Z, Get shorter gears in that car. 3.7, 3.9 or 4.11 with a 5 speed would certainly help with launches and autocross duty as well.

 

I'll let others talk about injectors and part numbers since I didn't keep the info when I got rid of the cars and those motors back in the mid/ late 90s. You can get about 230-250hp with 10-10.5:1 compression, enough cam, enough fuel, and enough exhaust...BUT it will be finicky and you will spend some serious bucks. First thing I would personally do is get the NISMO crank and rod bolt set, as well as a good set of total seal rings, and nismo head bolts. I'd get a performance prep on those rods, and if you can afford it, run good aftermarket pistons and have the head completely redone. If you can, upgrade to larger valves like the ones sold at Arizona Zcar. Now, look at the list of parts I just recommended... The machine work alone is gonna cost you about $1500 - $2000. That is serious bucks not including the hardware to build with. However, this is in my opinion a better way to go than the L6 stroker option.

That is a start... come on guys lets kick this one around a bit... what did I miss, and what have you guys been doing with these things lately, as I haven't built a serious L6 since 1996.

 

Mike

 

------------------

 

"I will not be a spectator in the sport of life!"

mjk

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