Actualy what I find confusing is in one post it states the LE2 is similar to the CC 306 (The cam I am running ) and you state it is similar to the GM 847. While the duration numbers are similar the lift is not. If there is some kind agreement between you and the cam manufacturer then I guess you have to stick with it. Good luck with your set up and I hope you make the times your lookig for.

 

thats what i think too, that 383 needs larger CC heads to really shine!

it will perform tho when the tune gets dialed in just not to a 383's capabilities!! 400+ on TQ and HP with excellent under the curver performance is my prediction!

good luck and keep us updated

 

455RWHP 470RWTQ
thats my guess, but I'm not familiar with the LE2 stuff, mabye I'm being too optimistic.
Remember guys, this is a M6 with a 10 bolt, expect good #s.

 

Actually the added cubes of a 383 have a high possibilty to hurt power more than they have to make power.

HP is a function of TQ and RPM as we know and the problem with RPM is that port volume cross section plays a big part in allowing the motor to breathe at higher RPM.

So a head that works well on a 350/355 at 6500-7000rpm is going to work at a lower RPM on a 383.

That's why you see big TQ gains on a 383 and the same HP numbers as a 350.

To quote another thread

Those cross section numbers like TQdrivenws6 states above are still big when you do a traditional W x H formula because you don't account for the corner radius taking area out of the rectangle. For instances with a 5/8 corner radius you will take out .084 from the area. So a 2.12 sq in like TQdrivenws6 states is closer to 2.04sq in in reality. Makes Peak HP around 6200rpm, and that doesn't even account for the intake manifold and it's cross section and effect on HP peak RPM.

BTW I think Dave is WAY high on his guess. Lloyd has some good heads but LT4 and AFR headed Hyd Roller LT1's don't make those kind of numbers.


Bret

 

I think #'s in the 415 RWHP/380 RWTQ area are about right. It is a 6 speed and these will be TRUE TQ readings as opposed to an automatic and NICE converter that will spit out some WILD TQ #'s. I do not feel the extra 33 cubes from the 383 are much of a HP difference. This usually just peaks about 200-300 RPM sooiner than a 350 and makes the #'s a lil fatter in the mid range from what I have found.

I think the real impressive part will be #'s from 3500 RPM on up and what the average is from 3500 to 6500. He has already told me that regardless of what the dyno says, the car is FAST and he is pleased. It is always fun to romp on it in 3rd gear and spin the tires, LOL.

He has ran a few fast cars including a 410 RWHP car and put "bus lengths" on that one so even if the dyno #'s are only 400 RWHP/370 RWTQ (I am guessing they will be higher though), he is happy with the way the entire TQ curve accelerates the car even with the current mail order tune. Just like everyone else with this set up has mentioned, he was amazed at the amount of low end and mid range power the car has and still pulls like it does up top. Making good peak HP #'s is one thing, making the car fast requires a good and FAT TQ curve so that the HP and TQ curve are in the RPM range that they will accelerate the car the best. This usually means sacrificing a few HP up top but as long as the car is fatsre, who cares. We should still see some impressive #'s from this set up.

After a few pulls and some more tuning, I guess we will see the real #'s are on Monday.

Lloyd Elliott
972-617-5671
NightTrain66@msn.com

 

Wow, this is almost identical to what my new setup is going to be. Only thing is I don't have a tb, pulleys, afpr, or electric waterpump yet(which will all be here before spring). Also I'm running a stalled auto vs your 6 speed. I'm VERY curious to what it puts down. Make sure you datalog it and retune the setup several times to get the most out of the mail order tune.

You will have to pump up the fuel pressure to keep the 30lb injectors under 80% cycle duty. Let me know what you got the fuel pressure set at and what cycle duty you are running if you can, since I'm considering keeping the svo 30's.

If the tune is great(which is debatable unless you've already datalogged....no offense Ion, but it just doesn't get great the first time usually), it should do 420+rwhp no problem. BUT, peak rwhp means NOTHING.(my old setup peaked at 389rwhp but ran the times in sig) It's all about the torque curve.

My car should be on the dyno in a few weeks with this almost same setup, with a great tune and a stalled auto. Then I'll be getting some track times. I'm hoping to beat my old best(see sig), but on 255/50/16 drag radials this time.

 

The tune has been datalogged and it looks pretty good, but we will see for sure tonight on the dyno. I have this feeling that work is going to take forever today...

 

I'll be there to verify the numbers He gave me a ride in the t/a about a week ago and it was damn fast, time for a 9" and et streets

 

A Ford 9" or a 12 Bolt eat some hp/tq away?

 

Yup

 

I put out 390rwhp on 7 1/2 cylinders with an LE2 H&C package (One bad lifter). I am going to say 430rwhp.

 

405

 

I'd say around 417rwhp/400rwtq with a FULL tune on the stock 10 bolt..I made 390rw/390tq on Mail Order tune through a 12 bolt...More importantly speaking though, the car drives like a dream..Car drives like stock but it has 390rwtq on tap when needed Maybe oneday I will get a full tune and get the FULL potential out of my car..for now Im happy tho

Cody

 

Was your converter locked for that run?

 

I'm guessing peak 420/435 rear wheels. With a nice flat as a board torque curve that begins to taper down around 4500 rpm.