Datsun Roadster Forum-311s.org

I have a 69’ 2000 and am fully restoring it. I’m trying to find a good option for the engine. I’ve seen the most common being the k24a2 and would definitely be open for a v-tech engine. I’m looking for something less than 3o years old, aluminum, has decent power around like 180-230 hp, and ok gas mileage. Oh and not that expensive under 2500. So is there a better option then the k24? Or should I just go with the K?

Also what would be a good matching transmission

I don't believe there are any competing engines in the price range, HP, or availability of the Honda K24 engine.
I've heard there is a company making transmission adapters, because the K24 only comes in front/all wheel configurations. Don't know the name of the company, but the KA24DE 5 spd is among the adapters they make.

I would vote KA24DE instead of going the Honda route.
Seems to meet all the desires / requirements, especially the budget. Also, not a science project, lots of well documented installs.

Agreed. Plus, it stays Datsun / Nissan, which is good and likely good for resale down the road...

K-Swap.
Meets all requirements you desire. Especially the power one

Everything you need to know is in Rob's build:
viewtopic.php?t=34575

FergO2k wrote: Mon Sep 16, 2024 10:58 am I would vote KA24DE instead of going the Honda route.
Seems to meet all the desires / requirements, especially the budget. Also, not a science project, lots of well documented installs.

The KA (and SR) are great engines, but to make a KA (normally aspirated) come even close to the same power range as the Honda K-swap that will cost many, many thousands.

One may want to review max torque and at what rpm to compare engines. Most driving is done at around 3000-4000 rpm... you don't spend a lot of time at 6500+. On say, for example the freeway, you may get more smiles from an engine that responds instantly at 3500 vs a higher HP engine that makes torque a lot higher in the range. I DO LOVE a high reving engine and think the SR20 with variable cam timing (Robbs?) was amazing. The biggest difference that I've enjoyed in my own (U20) motor with the cam and induction changes has been the apparent increase in torque above 3000rpm... the way the engine responds I often think I'm in 4th when I'm actually in 5th.

Looking forward to your build!

I've been fortunate enough to have driven many variations of swapped Roadsters, built one myself, s13sr20de. The following are my thoughts and opinions from seat of the pants experience:

Ted's s15det w/6spd is a beast. This set-up is a blast to drive, produces easily as much power as a modified Roadster chassis can handle, overkill for many...me included. Ted's s13det w/5spd also produces more than enough power, I preferred it's 5spd tranny for drivability. Ted also allowed me to drive his Honda K-swap car. It was a VERY well sorted car. I did not find it as much fun to drive. To enjoy the experience of the available power, the engine had to be driven to higher rpms and continuously so. When the valve train came into it's power band, excitement happened, just not as usable in everyday driving. The exhaust note was not as satisfying as the sr cars.

Alexi's ka24de car is great to drive. It has more low-end torque and pulls strong at lower rpms. Speeds are at a par to my s13sr20.

My s13sr20de is the 1st generation sr20. It is a total blast to drive. Very quick and smooth, rev above 4000-4500 rpm and she hauls up to 7000 rpm in a blink of the eye, triple digit speeds are a snap. Easily drives 80 mph and 30 mpg no matter how hard I push it. The Jim Tyler exhaust sound is exquisite.

Sr20 and ka24 engines are very well supported through aftermarket suppliers. There are many members in our community that can offer knowledgeable advice on these swaps, Michael "Spriso" is always ready to assist with sr20 swap parts and info. They can be built up to tremendous horsepower levels ie: Eric's 450+hp asphalt ripping roadster.

Probably can tell I'm a fan of the sr20 and ka24 Nissan swaps. I do not know of anyone that has done a proper conversion that regrets the time and effort they put into it.

Pat

I'd keep in mind convertibles are outlawed on drag strips for a reason
So bumping up the ponys 80 & > might not be the safest thing to do , how's CO
state inspection, I see it has to be inspected initially ,I promised not to harp on it , but I think you should hear the steering column was known as a death spear in the SCCA racing circles after 72 or 73 and many would not drive /race a 311 ( 2 days a year pro Datsun racers ...came to the dealership I teched at ,talked racing ,we put their cars on a lift checked it over )

Convertibles are not outlawed on drag strips. NHRA has requirements for roll bars/cages for convertibles.

spl310 wrote: Mon Oct 28, 2024 3:16 pm Convertibles are not outlawed on drag strips. NHRA has requirements for roll bars/cages for convertibles.

They were around here in late 70s 100%, it's not great for the sport when a guys body parts are on the track after loosing it I remember some trying to get them on the track , a full pro stock only, strip tube classy roll bar etc. a different matter

Delete

spl310 wrote: Mon Oct 28, 2024 3:16 pm Convertibles are not outlawed on drag strips. NHRA has requirements for roll bars/cages for convertibles.

100% correct!
Drag raced my roadster many times



Back on topic, OP have you decided on the engine swap?

Riverrinker wrote: Mon Sep 16, 2024 2:04 am Oh and not that expensive under 2500.
So is there a better option then the k24? Or should I just go with the K?

$2500 Will not get you a SR20 rwd motor and trans. You could get a CA20DET in that price range, but you would have to bump the pressure a little to get the desired hp.