C3 383 + Torque Converter/Tranny ideas

[phantomjock]

Grumpy - Got a BIG Question or 2.
First I'll be away for 6 months - so there is time for me to order parts, get supplies and thoughts in order -- and think about my MODS.
I picked up a 383 from a local builder - here's the "Engine Analyzer" details. Haven't done a real Dyno - but he input all the parts (minus real exhaust etc.)


My tranny is a 200-4R.
I've sent my rear end off for a rebuild and and a new gear set - 4.11 (proposed--your thought -- please)...

One of my questions is:
1. The ""mix"" of Torque/HP curves - the rear end (as proposed) and the idea of a street(not daily driver)/Drag/Autocross application. I'd expect that there might be some transport time - ie driving to events - so that's why I was moving to the 4.11.
The rear end rebuild starts later this week - so there is time to pick gears still if you have a good/better idea for me! SO the rear end Gearing....

2. The other Big $$ question is the Torque Converter. Looking at the "Engine Analyzer Curves" -- leaves me wondering at the 3 "knees" at 2500/3000/3500 for torque. So if I want real Kick in the pants - do I go 3000+ - but with some driveability consider 2500 -- or keep the 2200 I have now! (Bowties Step/level II)

If you need any of the engine details this may help:


My plan is to get all these bits and pieces started so when I return from deployment - I can get my car built!

Ýou have a heap of info on the pages of this site and I can guarantee - IT will be a daily read for me --

Thanks and Cheers - Jim

 

[grumpyvette]

whats your car weight ?
and whats the tire diam.?
(ID need to know to do final calculations)
whats your main goal for the car?
will it be used mostly for transportation?
how much highway driving do you do?

read thru the links and sub links, theres really a ton of good info

btw The 200-4R Gearing is 1st 2.74, 2nd 1.57, 3rd 1.00, 4th .67
every choice is a compromise in some area
you generally divide 10.5 by the first gear ratio, of your transmission to find a ball park on the correct rear gear ratio, (provided your tire diam. is in the 24"-27" range, and youve got an over drive top gear ratio)

http://users.erols.com/srweiss/calcmph.htm

then take your over drive ratio and rear gear times your tire size and try to cruise at about 2400-2600rpm, at 70-75 mph in od top gear, like many cars in your case thats a 3.90:1 as the closest ratio, but 3.73 would be a better choice if you do much highway driving, with a 3.73:1 rear gear, youll pull a bit lower rpms in cruise mode than a 3.90:1 rear gear ratio
remember the GOALS are both explosive acceleration from a dead stop, and when passing at highway speeds and a reasonable cruise rpm, that falls in your engines power band...keeping in mind your rarely going to spend long stretches cruising with a car like this, so you generally don,t use od gear much

read thru these
viewtopic.php?f=71&t=555

viewtopic.php?f=71&t=1715

 

[phantomjock]

Thanks Grumpy!
Now I've got my homework assignments -- it will be easier to get through than the entire site.

Regarding the goal(s) of EXPLOSIVE Acceleration from a dead stop AND passing -- you're spot-on.
I'd expect to do the limited OD use - but would be occasionally driving to other locations.

Enough of my "blather" I'm to the BOOKS!
Thanks - Jim