I was wondering, all of these ferrari's and lambo's and F1's and CART cars all have low displacement V8's. How hard would it be to build a Small Displacement (3.2L or below) LT1, would it be possible? Would you have to get a different block to do it? I have always wanted to do something like this, Small displacement v8 with a Turbo. Maybe it's a stupid idea, but I think it would be cool.

 

Beyond the obvious questions of why you'd want the size and mass of an iron block V8 if all you're trying to do is create a 200 CID engine, and why you'd bother to turbocharge such a creation after artificially limiting its power potential...

3.2 liters would be about 200 CID (~197). To arrive at that using an LT1 block with a stock 4.00" bore, you'd need a crankshaft with a 2.0" stroke.

2.0" stroke * 4.0" bore * 4.0" bore * 8 cylinders * 0.7854 = 201 CID.

If you had to clean up the block with a 0.030" overbore, you'd end up with a 204. No such crankshaft exists, to my knowledge, at least not in a V8 configuration with a 1-piece rear main seal, so think custom-made billet crankshaft. Think $$$.

In such an engine, a normally "long" 6.0" rod would give you an extreme piston compression height of 2.025" (with a stock 9.025" deck), so you'd want a set of 6.5" rods to cut compression height down to ~1.525" and reduce the piston weight. Once again, everything would have to be custom made. More $$$.

At that point, you've got a bottom end that theoretically could turn 10,000+ rpm without breaking a sweat (piston speed in fpm = stroke * rpm / 6 = 3,333 fpm @ 10,000 rpm), but you're limited to a pushrod valvetrain with fairly large valves that you have to control. Solid roller is a given, but the spring pressures required to control the valves at that rpm would be extreme. Basically, you'd have an "F1" bottom end, but with an NHRA pro stock top end that required frequent rebuilds.

Bottom line, if that's what you want to do, the LT1 is the wrong platform to start with, and for the money spent, you could go the opposite direction and radically increase your power potential with more cubes and less rpm, especially if you plan on using forced induction.

 

It was theoretical on the LT1, but what block would be optimal? Is there any way to build a motor like this without spending an outrageous amount of money? I actually had no intentions to do it with an LT1 or putting it in a Camaro, I just used the LT1 as an example. Would a 3.2L V8 have any strong points? I love the way the CARTS and F1's and Indy cars sound, and Ferrari's. I've never seen anyone build a low displacement V8, which Is why I started this thread. Everyone always goes with Big Blocks and Big cubes, I've yet to see a tech article in any magazing building up a Small , small v8, is it because there is no point in it? Maybe I'm just being rediculous, but at least I asked. lol

 

Ah, and why would you say a turbo would artificially limit the power? do you think it would be a big breather?

 

If almost any racecar sanctioning body would allow more displacement, everyone wold jump at doing it. It takes BIG, make the HUGE money to get 900+ NA hp from a gasoline burining 183 cube engine. It also takes a power peak around 18,000 and more than 19,000 red line. See F1. Of course they are going from V10 to 2.4 L (146 cu. in.) V8 for 2006, so here goes the money again!

Some of what sounds so cool is the number of exhaust pulses you hear per second. (Hz). 400 Hz for a 6000 rpm V8, and 1600 Hz for a 19,200 rpm V10.

A Top Fuel dragster is 560 Hz at speed, but there is so much EXTERNAL combustion going on in the headers (along with the INTERNAL) the noise and pressure is unbelieveable.

You can achieve some of the neat sound by careful design of exhaust systems not only in how the firing pulses are mixed, but by which frequencies are attenuated and which are let thru. Ferraris, whether V8 or V12 sound like a Ferrari. I think they use flat (180 degree) cranks in their road V8, but 180 degree headers on a 90 degreee crank V8 can be made to sound a lot like that.

As for building a tiny pushrod SBC, Smokey spent lots of years doing that for Indy, I believe.

If you want the "sound" build a 3 inch stroke 5.0 L SBC to turn near 8000, and plumb it with 180 degree headers, and tune out the lower exhaust frequencies. You'll get about 530 Hz and the "ripping canvas" snarl. It won't be cheap, and it won't necessarily be fast, but it will sound COOL!

OK, one other way. Find the smallest V8 DOHC engines you can, and bolt a pair of them end to end, with a 45 degree difference in TDC. At 7500 you'll have 1000 Hz.

 

Then what would you be using it for, and what would it go in?

All OHC engines, and most with more than 8 cylinders. Start with an OHC platform and consider adding cylinders.

Not really. For the same money you can increase cubes and power potential, and that's generally what people are interested in, especially with an OHV platform where rpm is somewhat limited, and in relatively heavy street cars.

The only legitimate reason to destroke an engine is if class rules dictate a displacement limit. That's why Chevy made a 302.

The turbo wouldn't. Artificially limiting the displacement you could be filling with the turbo would. Why turbocharge 3.2 liters when you could turbocharge 6.5 instead?

 

Thanks for answering, the reason I asked was mainly just beacause I'm bored, and the weather is ****, so I'm dreaming. And it's never a bad day to learn something new. Thanks!

 

i don't care for certain sounds. some ferraris (to me anyways), sound like they run out of breath in the upper RPMs. This car is a BRM v16. i guess 16cyl at 12000rpms does some good. the only problem is that the car would misfire and turn off at high rpms, i think they changed the engine regulations before they got to figuring out what was wrong with it. too bad, cause it was a really strong engine.
ear candy:
http://gpl.krej.cz/mp3/BRM%20-%20loud%20pass.mp3
http://www.auto.bme.hu/autosport/mot...M_V16_Mk_2.mp3

 

Damn , that motor sounds so bad ***.

 

Just a "for the record" thing here...

The best chevy for revs, an I mean in a "stock-ish" situation; was the 302.

If you wanted to do a small displacement, high revving chevy; you would want to start there in your planning.

But as the others have said...
With the relatively low cost, large displacement options available to you, you should just go that route. And if you wanted to build a small turbo motor for big HP, you would actually be well served to begin with one of those 3,000hp capable blocks from... I think it was T/A...?

 

I you wanted a high revving SB V-8, that would be a good candidate for the nearly mythical Arao 4-v heads.

Rich

 

It all sounds fun in theory, but there is little reason to destroke a motor IMO. There is always more power in more cubes, plain and simple.

Sometimes there is a point of dimishing returns, but it is alot like a function with a maximum value. If you destroke it too much, you lose cubes and if you stroke too much you run into money and strength problems.

So there is middle ground where you need to find where you can have a balance between RPM, stroke, boost, money, and reliability...

If I were to get the most power possible out of a SBC, I would get a decent stroker (~434 CI on a tall deck) and throw some boost at it. You could easily hit 8k rpm on a solid roller and at 20 PSI make some sick power that a 3.2L couldnt even touch... the powerband should be a given.

Then again, never forget...... fast, reliable, cheap (pick 2)

 

Yes, Smokey spent tons of time and effort into making that little engine work. Nothing ever transpired though. He was extremely frustrated with the whole thing. When it did run great, it was spot on, but didn't last long.

-Shannon

 

I have always wanted to build a variety of engines just for the fun of it really, even if I don't end up putting them in cars.
On the subject of small V8's, what I'm planning to build next is the old buick/rover 215ci. 3.5 litres (or more 3.9, 4.5 or even 5, but these engines cost more) all aluminium (300lbs complete) and have great power potential with reworked heads. I saw a 2500lb car running high 8's with a 3.6 litre example with seriously reworked stock heads. Plus the blocks are stroooong. I figured I might build one and eventually drop in in a fiero - imagine a fiero thats even lighter, has better weight distribution and about 350hp, that'd be nice.

 

http://www.radicalextremesportscars....iven/index.php

Basically its hayabusa heads on a custom built v8 block. For you that dont know, the hayabusa is a 1300cc suzuki motorcycle that hauls ***.