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enginehelp
enginehelp
6/22/20 8:26 p.m.

I am in the midst of planning a build with lotus europa body content and bonded aluminum elise/exige chassis content. Granted it won't happen for a while because of finances and such but I want to keep planning it. However, I can't seem to choose an engine. (Should note I am planning to use a 1st gen boxster transaxle) What I want in my engine, in ranked order, is

 

1) Most important, Specific power per pound and per liter

 

2) Character and soul, High revving, good sound, interesting and just soulful engine

 

3) drivable

 


My favorite options so far are:

 

KLZE V6 turboed with forged rotating assembly and ferrea head internals, ported heads, and cams to rev to 9.5k-10k:

Good: DOHC, cheap core engine, amazing sounds like an f1 car, very characterful, crazy specific power both per liter and per pound, CRAZY HIGH RPM!!!!!!!!!!!!

Bad: Not too drivable if drivable at all, 10k rpm, torque everest rather than torque curve, wide

 

1UZ-FE V8 turboed with forged rotating assembly, head work and porting to 8.5k-9k rpm, new cams: 

Good: CHeap core, DOHC V8, much more drivable than ^ yet still high revving, characterful, great sound, much better torque curve than ^, great specific power, cheaper to build than ^

Bad: Wide engine, pretty big overall, not the cheapest to build, less characterful than ^, less specfici power than ^

 

LS4 ported heads with new springs, forged rotating assembly with turbos, new cam

Good: CHeap core and cheapest to build, highest power, best power per dollar, most reliable, most compact overall, easiest to get, easiest to build

Bad: BORING, not very characterful, lowest revving, lowest specific power, heaviest

 

Those are the biggest but I had a couple other thoughts:

 

Taurus SHO v8, but can't really rev too high, was thinking maybe a head swap??

Coyote v8, probably the most sensible choice but most expensive core engine and expensive engine parts and kind of boring

Hayabusa, Crazy engine but it would be too taxing to have it in a car that will be driven hard IMO

VQ35, Great engine but kind of boring

 

What do y'all think I should go with?

captdownshift (Forum Supporter)
captdownshift (Forum Supporter) GRM+ Memberand UltimaDork
6/22/20 8:37 p.m.

KLZE or 4AGE

You're building something that weighs 16 pounds so torque isn't needed and thusly you won't need to rev it over 7k unless you're looking to have fun. You're also going to be driving something that becomes a casket from the first distracted crossover driver with 42" wide C pillars and 10" A pillars can't see you. Thus revs are your friend.

barefootskater
barefootskater UltraDork
6/22/20 9:01 p.m.

You may not get 8000 rpm from a boosted LS, and it may be played out, but $3-4K will get you a dead nuts reliable 800hp, without even trying hard. I don't care what it looks or sounds like. That's F U power in a car that light

enginehelp
enginehelp New Reader
6/22/20 9:21 p.m.

In reply to captdownshift (Forum Supporter) :

Well that is a very definitive answer, thank you so much. I hadn't given much thought to the 4age because cast iron inline four is not too alluring but I am kind og in love with the klze. Do you think it's worth it to build it to 10k or should I keep it around 8-9k

enginehelp
enginehelp New Reader
6/22/20 9:23 p.m.

In reply to barefootskater :

That's part of what makes this so hard, they are all so great in their own ways. But I'm f definitely not doing 800hp in a 800kg car, maybe 500, 600 at most but 1:1 hp:kg in an aluminum casket is simply too much. IDK though it's just so hard because it's a great engine....with ZERO character

Dave M (Forum Supporter)
Dave M (Forum Supporter) HalfDork
6/22/20 10:06 p.m.

In reply to enginehelp :

I dunno, I think zero character is taking it too far. It's common for a reason, and because it's common, and not high revving, we say meh. But I think an LS with an exhaust sounds good.

But then again, I don't think a coyote sounds boring at all...

Anyway, I'd think about putting something light and boosted in there, like an Ecotec.

enginehelp
enginehelp New Reader
6/22/20 10:28 p.m.

In reply to Dave M (Forum Supporter) :

Alriight fair enough it is taking it a bit far but it's nowhere near the character of the others

 

I am leaning closer and closer to the klze because it is exceedingly light and like boost

Appleseed
Appleseed MegaDork
6/22/20 10:48 p.m.

What about one of Toyota's 2ZZ? Lotus spins theirs to 8,500 rpm in the 2ZZ-GE.

enginehelp
enginehelp New Reader
6/22/20 10:59 p.m.

In reply to Appleseed :

I thought about it but it's a middling displacement i4 and I find it pretty boring. I don't really want to go with an i4, I know this is very arbitrary but IDK

codrus (Forum Supporter)
codrus (Forum Supporter) GRM+ Memberand UberDork
6/23/20 12:40 a.m.

Shouldn't there be a rotary on the list?

 

enginehelp
enginehelp New Reader
6/23/20 12:46 a.m.

In reply to codrus (Forum Supporter) :

Ahhh there probably should, hadn't thought of that because of all the terrible things I hear about them- Terrible fuel mileage, terrible reliability, difficult to work on etc. However, Re-Amemiya did a really nice one. WHat do you think?

frenchyd
frenchyd PowerDork
6/23/20 3:32 a.m.

In reply to enginehelp :

I'm an old school kinda guy. I love the idea of a Cosworth Vega or a Olds Quad 4. But I'd toss away the EFI  and go mechanical fuel injection.  Then use a Kinsler Dial-a-Jet  to select gas, E85 w/60%  alcohol, 85% alcohol,  premium,  race gas.  
I suppose you could do that to a solid 1/2 dozen 4 cylinder 4 valve engines.  

captdownshift (Forum Supporter)
captdownshift (Forum Supporter) GRM+ Memberand UltimaDork
6/23/20 8:54 a.m.

F20C plus boost should also be strongly considered

enginehelp
enginehelp New Reader
6/23/20 10:07 a.m.

In reply to frenchyd :

I think you've won the coolest competition, that would be insanely awesome and terrifically impractical, and I love it. Unfortunately I'm not the biggest fan of those engines for modern usage but it would be insane

enginehelp
enginehelp New Reader
6/23/20 10:08 a.m.

In reply to captdownshift (Forum Supporter) :

You're right. Ugh I now have even more choices haha

bobzilla
bobzilla MegaDork
6/23/20 10:15 a.m.

Don't make me say it. 

EDIT: just got to the "don't want an inline 4". Oh thank god. I didn't want to be the one to suggest a Kswap. that makes my soul cry a little. If I had one. Silly soulless gingers. 

 

enginehelp
enginehelp New Reader
6/23/20 10:44 a.m.

In reply to bobzilla :

See those are all sensible, practical engines - 2zz, kseries, b18, b20, f20, f22, but I just, arbitrarily, find them so boring and not fitting for what I want. That's why I love teeny tiny 2.5l v6s and such

oldeskewltoy
oldeskewltoy UberDork
6/23/20 11:58 a.m.
enginehelp said:

In reply to bobzilla :

 That's why I love teeny tiny 2.5l v6s and such

go with the tiny V6... it really seems like that is what you really want to build... and as this is a project... you need to keep motivated... so build what motivates you

 

bigdaddylee82
bigdaddylee82 UltraDork
6/23/20 12:17 p.m.

Build a high compression, B5254S, with ITBs.

 

The BTCC Volvo Omega cars were 2.0l, spinning up to 8500 RPM, and getting close to 300 HP.

 

I think technically the BTCC engines were based on the B5204FS, but I don't think you're likely to find one in North America, assuming you're in North America.

enginehelp
enginehelp New Reader
6/23/20 1:22 p.m.

In reply to bigdaddylee82 :

WHat an engine!!!!!  I5? Now that is interesting, low displacement, characterful, interesting, high revving, and pretty powerful. More choices ahhh!!!!

captdownshift (Forum Supporter)
captdownshift (Forum Supporter) GRM+ Memberand UltimaDork
6/23/20 1:47 p.m.

In reply to bigdaddylee82 :

I also don't think they did that on pump gas or E85

Tom1200
Tom1200 Dork
6/23/20 1:51 p.m.

I love inline 5s they make a great noise.

The 4AG is hard to pass up as they can be built into full on Formula Atlantic engines making 260hp. Dial them back and the car might actually be streetable.

enginehelp
enginehelp New Reader
6/23/20 3:10 p.m.

In reply to captdownshift (Forum Supporter) :

Well yes but with low compression and some turbochargers it could probably make similar power with e85 or pump, I'd have to do more research

enginehelp
enginehelp New Reader
6/23/20 3:12 p.m.

In reply to Tom1200 :

I've never heard an i5 irl but online videos they sound brilliant. And it'll fit in the europa engine bay and it's a bloody beautiful engine.

 

I will pass up the 4AG lol, I cannot commit to an iron block i4. I have a hard time committing to any i4 but certainly not iron block

I wouldn't talk you out of the KLZE, that would be high on my list and the end result could be awesome!

On the 4A-GE note, many folks dismiss them as "heavy" iron blocks....they are actually very light when compared to lots of other smallish inline fours, for example, when in similar states of dress, they are lighter than either the Nissan SR20DE or the Honda F20C...and they love to rev! I'd still go KLZE V-6 for your project, but I had to jump in on the 4AG discussion.

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