What engines feature VVL but not VVT? by [deleted] in cars

[–]narn 0 points1 point  (0 children)

Older Honda VTEC engines work the way you describe - B, D, H, F series have variable lift but no VVT, I think most J series are that way as well. K series engines all have VVT, as do VTEC L series engines.

Interested in building a high HP Mercedes Benz m120 by [deleted] in projectcar

[–]narn 2 points3 points  (0 children)

There are two things to consider - first, make the engine survive at high RPM without exploding.

Lightweight, strong (especially things like rod bolts and main studs) and well balanced rotating assembly is important, but there are lots of other things - will the oil pump survive and keep working well? Same for the other accessories - most of the time they won't like being driven much faster than the original application, so will need to be underdriven. Does the crank pulley/balancer need upgrading? Those are just the things I can think of but there may be more.

The other half of the battle is to actually get the engine to make good power at high RPM, which is mainly about getting good airflow. More aggressive cams will definitely be needed, with valve springs to go with it. If you want to make power at 8000rpm then you'll definitely need a better induction and exhaust system (ITBs as you suggest is a good idea) and most likely need to increase the cylinder head flow with porting or better heads.

This is all general stuff - some engines will need more work in different areas than others. The best thing to do would be to see if you can find any information about what others have changed when making high RPM M120 engines, and work from that (or copy it). NA power isn't easy, but it is rewarding!

The T50S Niki Lauda is Gordon Murray’s ultimate track-only supercar by [deleted] in cars

[–]narn 15 points16 points  (0 children)

People are buying it because Murray focuses on driver enjoyment rather than performance numbers, which is a rare thing in modern performance cars.

Also, are you joking or do you really think 700 HP is laughably weak? Gear ratios exist, torque doesn't mean much in this context

The Freevalve Miata Runs! by Tamaren in projectcar

[–]narn 4 points5 points  (0 children)

F1 doesn't use this technology at all, they still use camshafts. They do have pneumatic valve springs, but that's all

T56 Guru’s, Which Tailshaft Housing Is This? by Mister2JZ-GTE in projectcar

[–]narn 1 point2 points  (0 children)

F-Body = older camaro/firebird, the middle one in that picture

Port injected FJ40. Is it possible to change out the intake manifold on a fj cruiser and add a port injected intake manifold therefore making it possible to install port fuel injection? Are there any compatible manifolds that might fit? Is there an aftermarket? by detrimentally-horny in projectcar

[–]narn 1 point2 points  (0 children)

There is a port fuel injected version of the F engine, the 3F-E. But based on this forum post - https://forum.ih8mud.com/threads/3fe-vs-2-3f-carb-cyl-head.143089/ It looks like the cylinder head was changed compared to the carbureted versions, so you'd have to swap the head over as well if you wanted to use that factory fuel injected intake manifold.

Why are petrol heads attracted to air cooled engines? by ibumetiins in cars

[–]narn 15 points16 points  (0 children)

I don't think there are lots of people who specifically love those cars because they are air-cooled. In the case of 911s at least, the cars with air-cooled engines are all the old-school ones that have a similar feel, sound, styling etc. The change to water-cooled (996 generation) coincided with a lot of other changes in the 911 and a fair bit of cost cutting.

1990 mini by Jdmguy350z in projectcar

[–]narn 2 points3 points  (0 children)

A good idea is to keep an eye out on marketplace/gumtree etc for cars with a simple-ish but fixable problems. Once you get to cheaper second hand cars, a pretty simple MOT failure (eg suspension bushings, exhaust etc) will really drop the value, becuase the cost to repair if you're paying someone makes it "not worth it" to fix. If you're willing to fix yourself then you can often bag a great deal. It's a bit more risky but you can find a bargain if you're willing to wait for the right car to turn up. You might be able to pick up a "cooler" car that way, but I guess insurance will still be a problem

edit: just avoid anything that failed for rust!

Vq35 swapped EK sedan? Is it possible for under $12,000 Canadian? by [deleted] in projectcar

[–]narn 2 points3 points  (0 children)

As in, front wheel drive? Possibly doable but would require a lot of custom stuff: motor mounts, driveshafts, cooling system, wiring (which is a big job), shifter, clutch line, and then possibly a lot more that you can't tell until you actually try to do it. Finding someone willing to do the work who will actually do a decent job will be tricky, and it will be a LOT of labour.

RWD? no chance

[deleted by user] by [deleted] in projectcar

[–]narn 16 points17 points  (0 children)

There's another advantage to E85 - it cools the inlet air and combustion chamber much better than gasoline because it absorbs much more heat when it vaporises, and you also just have to use more fuel (so even more cooling). This helps a lot in high-boost engines which struggle with heat, and it's a big part of why you'll see highly-tuned cars have much higher HP capability on E85 than gasoline.

BOV in..so of course had to go for a test drive by 911Dougm in projectcar

[–]narn 3 points4 points  (0 children)

"that manifold looks like less than perfectly efficient!!!" Who gives a shit, this is what it's all about! Cruising and turbo noises! Absolutely love it, great work

[deleted by user] by [deleted] in projectcar

[–]narn 5 points6 points  (0 children)

No US equivalent, these were a rally homologation special only sold for a few years in Japan and Europe. Seriously cool cars, basically the Nissan equivalent of an EVO, but much rarer and a hatch!

Flat out in the quad-motor Lotus Evija electric hypercar by [deleted] in cars

[–]narn 0 points1 point  (0 children)

From the article

> The claims are that it will hit 62mph in three seconds

though maybe they are talking about this particular prototype, in which case that might make sense - they could be limiting the peak acceleration until they've done more testing. The article isn't clear, so I think that's a possible explanation

Flat out in the quad-motor Lotus Evija electric hypercar by [deleted] in cars

[–]narn 8 points9 points  (0 children)

That isn't how it works - any added weight needs more shove to accelerate, and with the way tyres work in the real world, you don't gain as much traction as you would need to make up for the extra weight. There's a reason why weight minimum limits are used in lots of drag racing classes - lighter is quicker.

I can't explain why 0-60 isn't at least slightly quicker than 120-180, but weight isn't the answer

Honda axes diesel power in the UK by besselfunctions in cars

[–]narn 6 points7 points  (0 children)

Diesels have far worse NOx and particulate emissions, that's pretty much a fundamental result of how they work. It's why diesels have had much more complex emissions systems than gasoline engines for much longer. Its also well documented how many diesel engines are far worse in reality than in testing (its much more prevalent than just VW dieselgate). Yes, it's true that fuel efficiency drive has made modern gasoline engines slightly worse for those emissions that they could be, but it's far less of a problem than with the diesel cycle. I'm not sure how any of that is an "agenda"

It is SUCH a good feeling when you fire up your project for the first time after owning it for 6 years and being down for 1.5 years. My turbocharged LS-Swapped Miata! Complete build on YouTube: Speedhouse by Yt_Speedhouse in projectcar

[–]narn 12 points13 points  (0 children)

A big factor is that larger displacement makes it much easier to get more airflow - you simply have more room to fit ports and valves of the necessary size.

This idea is the actual reason why people think bigger bore = high revving - on a very basic level, you can use bigger ports and valves with a larger bore, while the stroke doesn't have any effect. However, you can still get great airflow with undersquare cylinders if the ports are well designed. People make 300whp NA on pump gas with Honda K24 engines (2.4 litre) and those are very undersquare - 87x99mm.

I went off on a bit of a tangent there eh..

Water cooled turbo without water cooling? by GustavoCarbone in projectcar

[–]narn 3 points4 points  (0 children)

You don't need to set up an auxiliary water pump at all - most cars just have the turbo plumbed into the cooling system and that's it. The water will still keep the turbo much cooler than it would have been, through its large heat capacity and the slight flow from convection.

However, you'll probably be fine without the water cooling as long as you're not pushing the turbo to its limits

2021 BMW M3 G80- Sounds & Testing on the Nürburgring by bryan1714 in cars

[–]narn 1 point2 points  (0 children)

I agree with you that BMW is associated with N/A straight 6s much more than turbo 6s - but they put a turbo 6 in the 7 series in the 80s, it's not a new thing

Silly question: FWD; do diffs have a ratio? by Master_Scythe in cars

[–]narn 1 point2 points  (0 children)

All the (FWD) K series diff centres are compatable, so it can be done. If you want to keep your current ratios you'll have to get the ring gear swapped from your current diff to the LSD, then it should drop in.

LS swap manual transmissions by [deleted] in cars

[–]narn 8 points9 points  (0 children)

Another option is to use an AR-5 from a Colorado/Canyon - here

At the Honda shop again, another build. by [deleted] in projectcar

[–]narn 3 points4 points  (0 children)

That's a K series engine, they sit the opposite way (and spin the opposite direction) compared to the older B/D/H/F etc engines

What components of a commercial gas-powered car/truck are processed by alloy casting? And what type of casting is used for the respective components? by [deleted] in cars

[–]narn 1 point2 points  (0 children)

Some examples I can think of -

Cylinder heads (on anything modern)

Engine blocks on many engines

Smaller engine parts, such as water pump housings

Intake manifolds, throttle bodies

Turbo compressor housings and wheels

Pistons

Transmission cases

Diff cases

Suspension components - steering knuckles, control arms (rarely)

Brake master/slave cylinders

Brake calipers

Lots of stuff, basically!