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[daretobedifferent]

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Edited July 13, 2023 by daretobedifferent

[gav240z]

I've driven a 3.1 ltr L-series 240z with about 250-270HP at the flywheel and it was pretty rapid. Fast enough for most, with the right gear ratio's not much could touch it, not even most modern turbo stuff.

 

Since you have a 240z, I'd be inclined to keep the original engine. Non turbo they are super reliable and hard to break. They are also relatively fuel efficient all things considered.

 

But to each their own.

[PB260Z]

Gidday

 

What sort of budget you looking at for the Engine and related works ?

Will obviously make a difference to how far you take each engine and thus the results you will get.

 

Just my 2c worth.

 

And yes I have driven a couple of the options on your list

Edited August 26, 2015 by PB260Z

[C.A.R.]

Hey guys,

 

I've finally acquired a 240z project car, and I'm having difficulties figuring out what engine I'd like to put in the car. I've only owned first generation MX-5's, with my current MX-5 producing ~ 130bhp and weighing ~ 980kg. It's definitely slow on the straights but I don't find myself complaining when I'm driving around some windy roads. Therefore my goals for the 240z are:

1. Weight: <1000kg

2. Power: ~250bhp

3. Reliable: Able to handle abuse well, without causing too many issues.

4. Most of all, fun!

 

I'm not too concerned with originality, I'm more concerned about the driving characteristics of the car.

 

So I'd like to know your opinions on the differences in the driving dynamics (handling affected by the change in weight of the car) between:

1. L28 standard

2. L28 stroker builds (3.0, 3.1, 3.2 ...)

3. L28et

4. SR20 or FJ20 (N/A or Turbocharged)

5. RB20,25,26,30 (N/A or Turbocharged)

 

Please comment only if you've driven at least 2 of the above configurations for a comparison.

 

Keen to hear all of your responses.

 

Edited August 26, 2015 by Lurch ™

[peter mc]

A 350hp L stroka is so fast its hard to believe. I have driven every combo you have put up.. 3.3 and 3.4 are still my favorite

[260DET]

Something like a SR20 will give you a better than stock weight balance and help you reach your overall weight target too. I used to have a FJ20ET engined 260 which was about 50/50 but the FJ is a bit heavy and parts are getting hard to find so the SR would be my choice, to suit your criteria.

[PZG302]

For a road registered 240 that has the interior trim and keeping it under 1000kg, your dreaming. My race 240 was 960kg and it went to a serious session at Jenny Craig, I could have gotten another 10kg or so going to 'glass hatch and redo the wiring, but not much more.

 

The car was a stripped racer built to 2B rules so had an injected L28.

 

For 250hp, whether at the flywheel or rear wheels, for most engine combinations it will be expensive, for L series, budget at least $10k for a full rebuild depending on your base, my last freshen up was about $7k for the motor and another $3k for other bits and bobs that needed doing, that gave me 200hp at the wheels on the dyno used to tune the car, was good for 62 seconds around Lakeside on old slicks well passed their used by date on a 40 degree day.

 

For a road car, I would be looking at a mild L28, either on injection with an aftermarket computer, or on triples, but rather than out and out power, chase torque, my race motor was built by rally cars and had a very fat and broad torque curve so the engine worked from about 3500 to 6800rpm and pulled better than a 14 school boy. Unless you have deep pockets, I wouldn't worry about a stroker or conversion.

 

And spend a decent of money on quality suspension and brakes parts to make the car handle and stop, this will make it a better car to drive.

 

I have yet to have this proven wrong to me:

" If you want to go seconds faster around a track, spend your money on suspension and brakes.

If you want to go tenths faster, spend it on the motor"

 

[dat2kman]

Go the SR20 DET, with mild bolt on mods, and aftermarket ecu.

Set it well back.

Sort out suspension spring rates to allow for less weight over nose.

Plenty room to V mount intercooler and radiator.

[daretobedifferent]

Thanks for the responses guys. So far an L28 stroker build is definitely on the top of the list. Period correct, and as far as I know, an L28 swap does not need any form of engineered cert to get it registered. SR is definitely a nice swap, but swapping out a 6 banger for a 4 is a little bit disappointing (still on the list though).

 

@PB260Z: At the moment, I'm budgeting 15k for the engine, box, loom and cooling system. But in all honesty, I'll spend what is necessary as I go. If the budget has to turn to 20k, I'll just have to extend the build for another year to accommodate for that extra 5k.

 

@PZG302: With the weight of your race 240, is that with a full-cage? and is that a wet/dry weight? If its impossible to get it down to 1000kg with a daily-able interior, then I'm not too fussed, but getting it down to a low weight is ideal in my opinion. And not to worry, MX-5 owners know all about quotes like these;

 

" If you want to go seconds faster around a track, spend your money on suspension and brakes.

If you want to go tenths faster, spend it on the motor"

 

seeing as we don't have power to begin with.

[PZG302]

Mine was 960kg ready to go on the track with full cage and met the rules of 2B Marque Sports cars. The only other car i have seen lighter had some very scary work done to get the weight down, certainly not a car I would to have a crash in.

 

My standard Na6 gets around lakeside in 66's, so a well set up suspension is worth more than big power. i get passed by most down the straight, but get back passed them around the back where balance is more important than power.

[pauly_adams]

if you had a tight budget idd go L28et, for around $3000-3500 you can make 250hp with no problem (mine puts out 200+ rwkw at 12psi) the torque will break everything though gearbox, diff axels etc. if you have the money I would go L33 stroker made by peter mc you will get a awesome torque curve and good power

[dat2kman]

If you are interested in a complete new ready to assemble L29, that will spin to 8000, comprising of forged longer rods, short height forged pistons, knife edged crank, steel lightened flywheel, BHJ balancer, small diam ( less inertia) clutch assy, blck hot tanked, cleaned, fully machined, new cylinder head with all new valvetrain component, billet cam.

I am ok to sell at my cost price.

No induction/exhaust,, but go see Stew Wilkins for those.

[d3c0y]

"If you want to go tenths faster, spend it on the motor"

"If you want to go seconds faster around a track, spend your money on suspension and brakes buy an Evo."

 

 

Fixed.