3.1L L28 HP question
 

what Hp and torque can I expect from a
N/a 3.1 L28 with a very wild cam and 45mm triple webers, out to a 2.5" exhaust.

Has anyone hear done this to thier 240z? If you have how do you like it?
what do you like about it?what do you not like about it?

I am debating with myself over the 3.1 L stroker conversion, and the L28ET (280zxturbo) conversion.

The turbo it seems has to run FI for best results. I have always drooled over the sight of triple webers though.
I have never owned a turbo car so this turbo stuff is new to me.

I am looking for a good daily driver car+weekend race car.
If any one has had any experinece with
these conversions. I'd like to know roughly how much you will abmit the coversion would cost and any thing that you had to replace. (gas tanks, fuel pumps, gauge calibration, ect.)

Unless you have some prejudice against turbos like I once had, or have some class rules to obey, go turbo.

Hot stroker cars can dump 250-300HP. There is a 314 HP or so car, that is 13.5:1 compression and has a fairly large cam, and does not put out torque anything like a turbo car will, and no way will it get MPG like one either, expect maybe 10 MPG from what I've heard with tripples. Tripple cars also dont have chokes in the ones that I've seen, they are not going to be startup friendly.

You'd be in for more money with an NA stroker versus a turbo, unless you want to go nuts on the turbo setup. I got my turbo car for $150 with 70k miles on the clock, rear main looks new. I like injection myself, and once you learn how turbo cars work they can be run on pump gas and make great all around power. Stock torque peak on the NA L6 is around 4400 RPM, very peaky compared to a turbo car which should pull peak torque around 2800 RPM. Much better for all around driving IMO.

Plus, we are going to compare about 10 MPG to 26-30 MPG with a turbo car depending on your gearing of course, run a 3.54 rear with a turbo unless you can find a 3.36 :) Which one is better for a street car? I think it should be obvious.

Thanx a bunch,
I think its starting to make sense to me that turbo is the way to go.
The difference between 10mpg and 20+mpg is enough for me.
You also say there is a significant difference in torque, that pretty much seals the deal.

Now I have a lot of reading to do so that I can research this turbo stuff more.
i have located an L28ET in a junkyard close to me. However it belongs to the owner of he junk yard I know the car, I hope he doesn't change his mind about selling me the engine.

Definately a difference, the only way to make HP from an NA car is to end up making the setup more efficient, and to make it breath more - because it will need it, since to make power you will have to install a larger cam and rev it up.

Turbos make awesome torque which is one huge plus in thier favor, you can maintain a nicely driveable street car but still have power up top and in the middle with a turbo car, and if you stay out of the big boost you will still get good MPG. A local guy hits about 26 MPG average with 3.54 rear gears and 50PSI fuel pressure instead of 34 stock, so feeding it more fuel and still knocking down awesome MPG.

I learned the most about cars on an FI vehicle, and there are a billion reasons to prefer it over carbs for me. Sure there is more wiring but it is all worth it to me in the long run, I just dont like carbs at all. If it was a stock vehicle then SUs do fine and still bang down good mileage, if going for power though I want FI to maintain streetability overall as well as gas mileage which to me is part of a street car, especially when gas costs so darn much.

why not a 3.1 turbo? haha.. someone was selling a 3.1 turbo engine on IZCC for $7000 brand new....

I'd suggest the turbo engine over the stroker N/A... much more streetable.

BTW 40DCOE carbs have choke.. I have a 40DCOE on my '73 620 and not only does it have a choke, but it works very well

How much power
 

I am doing the exact same except I am staying with injection. My mechanic is very good with Z,s and says I should expect between 270 and 300 hp NA. I have to do a lot of creative adjustment to tha AFM and the throttle body.
I will let you know how irt goes.

I just thought I'd share this e-mail I recieved from top end performance about the issue:
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"The Turbo route is DEFINITELY NOT less expensive although you can make a
lot more power...
N/A on Pump Gas (91-92 Octane.) you can make 280-290 HP with triple 45
DCOE carbs, good exhaust and ignition.
That is doing a High Compression Big Bore L28 with the L28 Stroke
(Forget the Diesel crank stroker thing..They don't rev up well and
really limit the HP..) A LOT of head work, proper cam, etc...

We can offer a complete package with the engine and ALL the external
pieces needed to bolt into your car and make that level of HP....

If you can give us a call and we can hash out the details...

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Comments?(though they have already been made)
I am planning on spending about 5-7 grand on my engine swap. I guess I better call and see just how much more
expensive this turbo thing is......
I read this some where...
fast + good=not cheap
fast + cheap=not good
cheap+good=not fast

Thanx for your input,
Ernie H.