Has anybody tried the LE4 cam in a full weight 383 M6 with 3.42s and a light flywheel, for street driving? Or have similar experience?

As it turns out, that's what I'm building. I planned & built my 12.5:1 setup specifically to run the LE3 cam, for a fat torque curve and great streetability. However, I was informed today that I will need to run the LE4 instead. I'm not too happy about that, but hopefully it can still be the torquey street car I'm looking for.

I drive the car to work, frequently in heavy traffic, all summer. So, any thoughts on driveability with this combo interest me greatly.

 

Why do you NEED to run the LE4?

 

Where are most of these set-ups putting down 450rwhp? How many of these LE2's run 11.20's all day?

 

Why run only a 3.42 gear with a high revving setup?

 

javier and lloyd himself are running 11.20s.....

 

Err....

Lloyd is in the 11.50's and I've hit a best of 11.37 so far...

Unfortunately there are not as many low 11 second LE setups as there could be... and I'm not aware of LE2 cars in the 450 rwhp range.

Just being honest...

All that being said, I do love my setup.

And I agree, 3.42's with an LE3 or LE4 are a terrible idea. If I had a 6spd I wouldn't think of anything less than a 4.30 gear out back with those cam choices.

 

oh, my bad, i thought u 2 were both lower than that. The way i read that, is that most LE3/LE4 setups were in the 450 range, while most LE2 setups were in the 11.20 range

 

I am still 11.50/11.40 range but that aint bad at over 3700 lbs and 85-88 degree temps. Some night time track runs will help and it might be November before I see 11.30/11.20's. This Texas heat and humidity is AWEFUL until then.

Only a few LE3/LE4 s in the 450 RWHP range but there was a guy a few weeks back that made over 460 RWHP with LE2 heads and cam. Pretty good for mid 230 duration hyd roller and 561 castings.

The 383 is limited so much by these LT1 heads that the LE3 and LE4 cam still make TONS of TQ down low. The cubes and extra compression helps alot compared to the same cam in a 355.

 

If your heads flow around 260'ish on the intake (with manifold installed) and 200'ish on the exhaust I'd recommend a CompCams 3015/3111 on a 112 lobe sep (108/116).

Will work fantastically will taller gears (numerically lower... like a 3.07 in an auto or 3.45 in a M6) while making good vacuum. Peak power will be be down by ~10hp (compared to an LE2) but you'll have much better torque below 5000rpm. The hp/tq averages between the two end up the same.
You will lack the crappy idle (which for some reason is universally loved and equated with "bad *** power") but your driving experience will be enhanced.

It's the best compromise I've been able to come up with for a 350/383 and decently ported LT1/LT4 heads.

EDIT: I don't want people to think I'm attacking Lloyd or Brett. Their stuff does what they claim. But I want the forum members to be realistic in their goals as well and am offering my opinion based on experience (I've run an LE2 heads/cam combo for 2 years). I'll bet over 90% of you would be thrilled with an LE2 head/LE1 (or 1.5)cam combo. Remember, it's all about compromise.... You can go fast and hardly lose driveabililty or you can go really fast and start looking for a trailer rather than drive 2 hours to the track.

 

My LE3 doesn't have a "crappy idle", nor is it a trailer queen. Hell I still drive it to work on occasion.

 

Context my friend.
Is your idle set below 1000rpm? No problems with the A/C kicking on at idle either, I imagine.

Everyone has their set of standards. Mine are probably a bit different than yours. No one is better than another.

 

I have a cam between an LE1 and LE2, the idle is set at 800, and it idles fine with the ac, it never comes close to dying at idle, it idles smooth as hell, well it lopes but it doesn't search for the idle at all. Maybe you should find a new tuner.

 

Same here with the 847, its all in the tune

 

My idle is below 1000 rpm, not sure on the a/c yet, haven't recharged it yet to test.

 

Auto guys shouldnt give any input on cam surge/roughness You guys got tq converters to eat it up.