need theory help

[kridgley]

Hey all:

Corvette's been running real nice - started thinking about more power, now that I am starting to have the money and time to do it. However I wanted to do this in stages, not everything at once to help out with money. I currently have an L82 with the TH-400 and 2.73 gears ... not very quick.

Here's what I was thinking:
3.73 gears for good low end
new TCI tranny - streetfighter series look good -- change from 3 to 4 spd th-400
Gear Vendor under/overdrive (for better cruise rpm's)
ZZ4/355hp or ZZ383/425hp
maybe a supercharger - but prob not -- 425 is plenty for street.

I dont intend to race spectacular 1/4 miles or anything - I just want the corvette to stir up trouble a little trouble

In steps, I will probably do the gear swap and tranny swap first. Then do the engine swap later. So asking the experts - is this an ok plan of attack, what should be changed, and what would you change (within this price range)??


Any feedback if helpfull feedback


Thanks, Kevin

 

[AKRAY4PLAY]

your plan is good, but a little expensive for your goal. i like the GV overdrive with TH-400, but since you are planning on keeping hp down around 400 you may want to considder the 200R4 tranny. it will save you about a grand, give you four forward gears and is a direct bolt in swap. as for motors, the ZZ4 is a great off the shelf power plant. since you want to pay in stages, why not build your own motor slowly over time as the budget allows?? i like big displacement small blocks. best of both worlds, small block weight and big block power. rear gears are a function of engine torque and tranny gearing. once you settle on where your torque curve is the rpm band, and what tranny you plan on having, rear gears are an elemental calculation. generaly speaking the 3:70's are a great blend of performance and ecconomy with the 200R4 tranny.

 

[kridgley]

would you suggest any sources for building a good powerfull motor from scratch? Sounds like it could be cheaper, and more fun.

 

[KANE]

new TCI tranny - streetfighter series look good -- change from 3 to 4 spd.....
In steps, I will probably do the gear swap and tranny swap first.

I'd go with the tranny and rear end first!! Sounds like you are headed in the direction I'd go first!!

 

[AKRAY4PLAY]

would you suggest any sources for building a good powerfull motor from scratch? Sounds like it could be cheaper, and more fun.

i like small block 400s. they are a little hard to find and have a few quarks to attend to, but the rewards are well worth the extra trouble. i would look around for a 400 two bolt main block. check junk yards and old-timer motor shops. the sixties and early seventies motor head dudes usually have a block or two laying around. since you want to keep power down and make a very streetable combo, the 400's torque curve would be an ideal platform to build from. you can run just about any tranny and/or rear gear combo and still have a great car. the other option is a 383. there is probably 10,00+ ways to configure a sb chevy motor, but the 383 and 400/406 options are very common. naturally the parts kits are lower priced from mass production as well.
pricing for a strong reliable 383 or 400:
$1000 for rotating assembly, pistons-rings-crank-rods-bearings
$1200 for a nice set of heads, i recommend AFR 195's for this build
$1000 for intake, ignition, ARP bolt/stud kits, cam, water pump, timing assembly, gaskets, oil pump, oil pan, etc.
$600-$1000 for machine work on block. line bore cam/crank, bore cylinders, deck cylinders, install deck plugs, thread lifter valley for vent tubes

so for about $4000, you can get a 425-450hp 400sb that makes 500-550tq and does not need to rev over 5800 rpm. granted you will need to do some block prep like grinding flashing, opening oil returns, brushing and washing, clearence the rods and assembly work.

a little disclaimer to keep in mind!! if you plan on or even entertain the thought of going over 450hp and 550tq, you need a stronger tranny, and better internal parts in the motor. a propperly built 200R4 is maxed out around 525tq. with a beefy motor your idea of a TH-400 with a GV overdrive is the strongest option available. i like over building things because i hate broken parts and cool old cars that can't roll down the road under their own power. as for the internals of the motor, the balance job and choice of parts determines how high you can rev and how much torque it will take before grenading. nobody builds a 1000hp small block and puts a cast crank in it. feel free to pm or email me if you are interested in some of the 383/400 combos i've built and/or researched. Brian