texas94z

After reading about the straight 8 engine, the design died off was because of the the physical length. Manufactures couldn't fit a straight 8 into a modern cars. They were used in luxury and sports cars for 50 years. Lets say GM ditched the V8 design and adapted the straight 8 design for the LS Series. The main benefit of a straight engine is the limited torsional vibration. That means better bearing wear and less friction. Straight engines run very smooth and have a smooth acceleration.

Would a straight 8 LS Series engine outperform a V8 LS Series engine?

Also don't argue about disadvantage of length and weight.

battousai

iTrader: (3)

well, most straight 6's have more torque than their v6 cousins, so I think that would mean even more torque for the I8's.

1989GTA

Sure, it could be done quite easily. However because of the packaging it won't be. You could lay it over a little and that would create some interesting intake and exhaust situations that you cannot do with a V8. One thing would be exhaust pipe pairing.

1 FMF

iTrader: (1)

where did you read about straight 8's ?
wiki has a lot of decent info on inlines from I-4 on up, the info under the I-5 is probably the most revealing.

would a straight 8 outperform a v-8 disregarding weight and packaging, I think so based on having a common exhaust manifold for all 8 cylinders so you can take more advantage of exhaust tuning. You also get even firing pulses per revolution opposed to uneven firing pulses of a 90 deg V-8.

I don't think a straight 8 would have less torsional vibration than a v-8, it would have more because the crank is twice as long. A straight 8 however is more balanced than a 90 deg V-8 in regards to 1st and 2nd order harmonics since the crank throws balance each other out. Whether the crank length and vibration would matter I don't know, the 90-deg V-8 has heavy crank counterweights, and an inline-4 which is probably more common has 2nd order imbalance and both can go many miles/hours so I don't think it's that big a deal regarding durability.

the thing is though, if you're thinking about changing the common 90-deg (cross plane crank) v-8 design for something better, yes an inline-8 is one way to go.
But there is the single plane crank v-8 that's used in race motors where the crank throws resemble that of an inline-4 crank, so it has 2nd order balance problems but the evenly spaced firing pulses allows for better exhaust tuning and it doesn't need crank counterweights so it has less crank mass and can accelerate faster, hence the use of it in race motors I suppose would mean it performs better than the crossplane v-8 crank so why not go with a single plane crank?

In regards to going to an inline-8 over a v-8, consider a v-12 is inherently balanced on 1st and 2nd order, it has 4 more cylinders over an 8 cylinder hence better output, and is 2 cylinders shortly than an inline-8.

theone61636

They kind of explored this idea a few years ago with the LL8 4200 Vortec Inline 6. Made 291hp 275ft-lbs. I would imagine an 8 would make quite a bit more torque very low in the rpm range.

There were some people who modified them...

Need_a_Camaro

iTrader: (27)

Where do I get that setup for the wifes Trailblazer?

Hemi2Slo

An inline 8 would certainly make more torque, but I would think that the horsepower would suffer do to the inline cylinders being less energy efficient, as with an inline six. However, a V10 or V12 LSX motor would be incredible.

Or even a W configuration. I believe that its BMW that makes a W12 configuration motor. It has a near flatline torque curve

94transbird

That is Bugatti with the W16. I think they have a patent for it too

gringo dfw

My BMW had a I6. Although horsepower was lacking the nearly 300ftlbs of tq was amazing

ScarabEpic22

iTrader: (1)

You're quoting the stock HP/TQ numbers for 06-07 I6s, the turbo one you pictured makes 400/400 hp/tq and was only ever installed in 1 02 TrailBlazer. Dang shame GM never let anyone with EFILive/HPTuners read the PCM, we're screwed when trying to tune for boost.

As for an I8, that would be interesting. Maybe for a coupe/truck with a long nose it would fit?

94transbird

Inlines are notorious for their torque. Look at the Jeep I6, that thing is used in all sorts of big tire applications.

And since a Fbody has such a long nose I think someone could squeeze it in.

LoudGM

iTrader: (12)

Straight 8's are gay as hell, maybe if you talked to your friends more you would know that already!!!!

PS: thanks foe ignoring us Sam

Koncrete

iTrader: (3)

Actually it's Volkswagen that has it...

Awake455

Wow, all the trouble of twin turbos and all they were able to get was 37% more power? I know it's not intercooled which hurts the big numbers but damn.