Your ideal powertrain swap? - Page 4 - Fuel Economy, Hypermiling, EcoModding News and Forum

cosmick · 09-11-2016, 10:03 PM

Quote:

Originally Posted by freebeard

Who has the Elio?

I count 6 posts in 16 minutes. You can hit the edit button within five minutes of posting with no penalty.

ADHD, sorry.

freebeard · 09-12-2016, 01:46 AM

S'okay.

Did you get the part about Elio hasn't shipped product?

serialk11r · 09-12-2016, 02:30 AM

Quote:

Originally Posted by cosmick

The boost pressure has little to do with lag. Being a 1.6L you want all the boost pressure the engine can hold. Choose accordingly. GM's 2.0L Ecotec can be built to 1200 horsepower.

In some sense you're right. With a supercharger, when you hit the throttle the supercharger will be flowing slightly more air than it does at steady state full throttle (full boost), quickly pressurizing the plenum.

However that pressurization takes a few tenths of a second depending on how big the plenum, throttle, and supercharger are. For 0.1-0.2 extra seconds the engine will be building torque, and that is perceptible lag.

With turbos, it's even worse. I have driven the FA20DIT turbo engine in the WRX and a BMW N20 powered car before, and it takes half a second to a full second before you stop feeling the boost building. I prefer the crisp, responsive throttle of an NA engine even if it means less power.

I don't really need high horsepower, I have a < 1 ton MR2 Spyder which at 190hp is already pretty fun. I think the sweet spot is somewhere in the low 200s. I only pick a 1.5-1.6L engine because it frees up space in the engine bay a bit and fits in with the spirit of this forum (fuel economy), otherwise I would have said Honda K24, which will do 300hp naturally aspirated.

cosmick · 09-12-2016, 08:34 AM

Not quite. Lag is time between putting your foot in it and feeling acceleration. Turbo lag is time waiting for any boost pressure in the intake ports. While it may take an extra tenth to get the extra pressure, you don't need full boost to feel the result. Having driven a mid 90s Z28 with a rear turbo, I can say that a quarter second of lag is no problem, and speccing the turbo itself and the tubing sizes is far more important than how far the turbo is from the engine.
I readily admit that 500 rwhp is more than enough for a 3500 pound car on public roads, but it does NOT matter how many mpg it does if it isn't fun to drive. Anyone who thinks 200 is enough has never driven 500.

Gasoline Fumes · 09-12-2016, 10:12 AM

Quote:

Originally Posted by cosmick

Anyone who thinks 200 is enough has never driven 500.

I drove a Jaguar F-TYPE yesterday. 500+ HP is incredibly fun, but I think 200 is more than enough!

Ecky · 09-12-2016, 10:42 AM

I raise your 500HP, 3600lb car one 500HP 1800lb car:

https://youtu.be/vOBL62GTR_I

^ I probably wouldn't want to own one though. I'm somewhat surprised to see as many all-out performance swaps being suggested here; I have a hard time accepting giving up a lot of fuel economy in the name of power. Any swap I would seriously consider wouldn't give up much in the way of economy, and preferably would improve in both.

cosmick · 09-12-2016, 02:32 PM

The guys with 600- horse turbo 4s arent getting any more mpg than the guys eith 600-horse turbo LSx V8s backed by T56s. Bumping the LSx to 900 hp is easy, and wont break it, and affe ts neither mpg at cruise, nor emissions. The 4 cylinder guys cant honestly make such a claim. So why not jump on the LSx bandwagon? Mpg doe s nt matter if it isnt fun to drive, every single mile you drive it.

Ecky · 09-12-2016, 02:37 PM

Quote:

Originally Posted by cosmick

The guys with 600- horse turbo 4s arent getting any more mpg than the guys eith 600-horse turbo LSx V8s backed by T56s. Bumping the LSx to 900 hp is easy, and wont break it, and affe ts neither mpg at cruise, nor emissions. The 4 cylinder guys cant honestly make such a claim. So why not jump on the LSx bandwagon? Mpg doe s nt matter if it isnt fun to drive, every single mile you drive it.

I have a blast driving my 67HP Insight. Horsepower isn't the only thing that makes a car fun.

freebeard · 09-13-2016, 01:08 AM

http://www.thesamba.com/vw/forum/viewtopic.php?p=8046668&sid=6d40e5383c52370667c871 027cc31096#8046668

This is a 25hp VW engine case that's been bumped from IIRC 1125 to 1578cc. Machined for Porsche valve train parts with Deano's reproduction Okrasa dual-port heads. I forget what the turbo is from.

What'd that get him (Darrel Vittone)? 151.4mph in the flying mile at Mojave, CA. I like the rear bumper extensions.

Also Jay Leno had a BMC Mini with a BMW motorcycle head on a recent yesterday's episode.

https://www.youtube.com/watch?v=baB9CjOmwWc

Frank Lee · 09-13-2016, 01:42 AM

Quote:

Originally Posted by Ecky

I raise your 500HP, 3600lb car one 500HP 1800lb car:

https://youtu.be/vOBL62GTR_I

^ I probably wouldn't want to own one though. I'm somewhat surprised to see as many all-out performance swaps being suggested here; I have a hard time accepting giving up a lot of fuel economy in the name of power. Any swap I would seriously consider wouldn't give up much in the way of economy, and preferably would improve in both.

Me too. After all, going fast and getting caught are very expensive these days. 100+ mph is a FELONY in my State. I can do that in my stock Tempo.

And if I do decide to engage in felonious behavior I'll do it on the V-Max. Why drag 3000 lbs of tin and plastic along with if I want acceleration and speed?