Does any one sell the flat plane crank and cam for the LSx?

[This message has been edited by Rickady88GT (edited 06-03-2010).]

EDIT: Nevermind me, I read "plain" as "plain" when you meant "plane"

[This message has been edited by dobey (edited 06-03-2010).]

Rick,

This guy claims to have bought a LS flat plane crank for $750. You might find more info on the LSx Tech Forum.

http://www.ls1tech.com/foru...r-ls1-lm7-motor.html

Sounds like you have a new project coming up?

180 degree cranks are RARE. Maybe if they were allowed in Nascar they'd be more common on the street.

The firing order is different, so you'd need a cam to match, which is at least equally rare.

Trying to sound like a Ferrari, are we?

Thanks, I am just wondering how the LSx sounds with a flat plane crank or "den of snakes". The headers will take up massive real estate in the engine bay, so maybe if there were a commercially available 180 "kit", it sure would be different.

I have a flat plane crank in my Lotus V8. I don't consider this engine to be the best solution for a passenger car as there is a tendancy toward buzziness. It's not bad at all, but it's there. Keep in mind this engine only has an 81mm stroke. My car has bi-y iron manifolds and turbos, so the noise output has been somewhat stifled. The exhaust note is a hard, flat, smooth "roar". It is very free revving, and sounds really good from 6 to 7K RPM . Not that great below 6k.
A better solution. IMO, is a regular dual plane crank and the 180 degree headers, if you can possibly fit them in your engine bay..
You can search you tube for GT40s (180* headers) Ferrari F40s (flat crank) and Lotus V8s. I think some TVRs had an AJP engine with a flat crank. There's a Corvette in there that sounds particularly evil with the 180* headers.
A lot of people have contemplated the crank conversion route for SB Fords, and Chevies already, and usually they just give up as it not worth the money to be "different".
http://www.youtube.com/watch?v=6XnD4cfX4S8

quote Originally posted by Will: 180 degree cranks are RARE. Maybe if they were allowed in Nascar they'd be more common on the street. The firing order is different, so you'd need a cam to match, which is at least equally rare.

COMP will grind whatever you like in the way of a cam.

[This message has been edited by Isolde (edited 06-03-2010).]

I seen a flat plane crank for a Lt5 when I had one waitng in the wings ..tried to buy it but got outbidded ..of course the guy also had the cams but it was way out of what I was willing to pay. The crank was a work of art but it went for about 1400

edit
IIRC, the crank cost 5k to make

[This message has been edited by Erik (edited 06-04-2010).]

There used to be a C5 vette with 180 headers on utube... might be worth finding it to hear what it sounds like.
With the firewalls at work, I can't get to Utube to find it.

quote Originally posted by Isolde: COMP will grind whatever you like in the way of a cam.

On a BILLET core. No one's going to have a cast core with that firing order.

quote Originally posted by Will: Even building customer 180 degree headers from scratch is going to be cheaper/easier than building/tuning a flat crank Chevy, much less Ford, Mopar or other, and will give you the SAME results in terms of sound ...

there is always a bit of roughness in the lower rpms on a 90 degree v8 with 180 degree headers at least in all the examples I've heard on youtube and other sources. Most likely from a slight difference in primary lengths and of course the lopey cams they tend to run. Also they tend to sound deeper in pitch due in part to the longer primary lengths needed to reach a commom collector.
On my N* 180 degree headers I have kept the primaries to the shortest length possible ..around 28 inches, hopefully this will help me achieve as close to possible the Ferrari sound even though it may sound more like an F430 than a 360

[This message has been edited by Erik (edited 06-04-2010).]

quote Originally posted by Will: Even building customer 180 degree headers from scratch is going to be cheaper/easier than building/tuning a flat crank Chevy, much less Ford, Mopar or other, and will give you the SAME results in terms of sound and power. The 180 degree exhaust pulses allow the headers to work with smaller collectors, which increase mid-range torque without sacrificing top-end.

Do you have a link to a site that has a formula or theory for 180 headers that I can use to think about when I am bored? I would like to use some type of custom header on my LS4 when I convert it to a 6 speed. It might as well sound different than other LS4's.

quote Originally posted by Rickady88GT: Do you have a link to a site that has a formula or theory for 180 headers that I can use to think about when I am bored? I would like to use some type of custom header on my LS4 when I convert it to a 6 speed. It might as well sound different than other LS4's.

since the ls4 firing order is 1-8-7-2-6-5-4-3 you would want 1,7,6,4 to share a common header collecter and 8,2,5,3 to share one as well since they are 180 degrees off in firing order from each other. So you would pair up the 2 outer cylinders primary header tubes on one bank with the 2 inner cylinders primary header tubes on the opposite bank into a common collector. The tough part is making the primary tubes equal length within the constraints of the space availible. Otherwise you will have exhaust scavenging disparity and a rough sound which negates from the whole purpose of using 180 degree headers in the first place.

It would be interesting if you didnt want to go through all the trouble of building them but to instead incorporate an x tube into the exhaust if its a true dual which is supposed to help balance and scavenge the exhaust pulses as well as make it sound more smooth pulses like 180 degree headers do without near as much labor involved as building a custom set of 180 headers

Finally here is an example of an LSx engine with 180 degree headers to inspire you
http://www.youtube.com/watch?v=UxnYj1cSsWo

[This message has been edited by Erik (edited 06-05-2010).]

OK, that is a start but what about pipe diameter, length, collector size. How long of collector, merged, tapered blended?
Would it be a goal to just get the pipe as short as possible?
Could the pipe be to short?
Lots of things I don't know about hearer design but I want to learn.

I am looking at under 7,000 red line and under 400 HP. (thinking about building up the LS4 to an LS6?)
That is why I would like a crash course in header design.

quote Originally posted by Rickady88GT: OK, that is a start but what about pipe diameter, length, collector size. How long of collector, merged, tapered blended? Would it be a goal to just get the pipe as short as possible? Could the pipe be to short? Lots of things I don't know about hearer design but I want to learn. I am looking at under 7,000 red line and under 400 HP. (thinking about building up the LS4 to an LS6?) That is why I would like a crash course in header design.

For a start, here is a nice little calc to help you out for primary size and collector size length based upon your rpm, c.i. and cam timing exhaust event http://www.wallaceracing.com/header_length.php

Do you want higher pitch like a Ferrari? If so I would tend to choose pipe diameters smaller and shorter. If I was going to run an LSx under 7k rpm I would most likely choose a 1 5/8 primary with a 2 to 2/12 in collector short maybe 8 inches at most if space allowed but really need to know the exhaust valve opening degrees BBDC to formulate a total primary length which probably would be in the low to mid 30 inches. It will ultimately be a compromise since you will have to be able to reach from one side of the engine to the other side and that sucks since Ferrari primaries are shorter ..just look at an F1 header to get an idea although they run in the very high rpm range

Also you are at a disadvantage since the LS4 is quite a bit more displacement than a typical high rev small displacemt flat crank v8 which tends to lower the tone of the larger displacment engine. Look at how a 4.3 Ferrai v8 sounds as compared to a 3.6 Ferrari although both sound wonderful I would want the higher pitch of the 360 over the F430. I expect my 4.6 N* with 180 degree headers to sound more like the 430 because of this but that is not really a bad thing, it's just a compromise that you have to deal with with 180 degree headers

A merged collector would be the best for performance but are higher cost than a simple formed collector

I would simply google 180 degree header, header design and find out as much as you can. There is some good info on some forums who have discussed this at length

[This message has been edited by Erik (edited 06-05-2010).]

The primary pipe dimensions will be the same with standard of 180 degree collectors.

The 180 degree collectors will be smaller than the conventional collectors and thus make more mid-range torque due to collector velocity.