View Full Version : All input please auto to manual trans


badazz81z28
11-15-2003, 10:22:00 PM
I want a manual trans in my 78 I have a auto right now. What would be the best route to go ? I really want the overdrive gear. I want the best cost effective conversion what are your thoughts? I need the trans to handle a 475 HP 406ci. Anyone recommend a place to buy? Or would sticking with a auto be better?

1981coupe400ci
11-16-2003, 01:03:00 PM
if ya REALLY want a manual with an overdrive a T-56 6speed will do nicley, but without an O/D i'd go with a rock crusher... a built up 700R4 would do nice for a O/D auto trans

COPO
11-16-2003, 06:14:00 PM
Good stuff here 1st http://www.chevelles.com/techref/ftecref15.html

------------------
Mark
4spd Z28's owned '68,'71,'77new,'78new,'80new,70 still,daily driver 87 G/N.
Home Page on 1970 Z28
http://members.rogers.com/mlvd/

Todd80Z28
11-16-2003, 08:02:00 PM
My answer is the same as the last three times you asked this. http://www.nastyz28.com/ubb/wink.gif The T56 will work just fine, but if you intend to use 6th, make sure you don't go too wild on the cam (225*@.050" or less, IMO). Otherwise, it's dead weight, and you'd be better served by a 5 speed. Trouble is, the TKO has crappy ratios, IMO. The 3.27:1 is too steep, IMO. The gear spread is too wide.

I don't know why Tremec won't put together an overdrive for an engine on the "ragged edge." Something like- 2.97:1, 2.07:1, 1.45:1, 1:1, .74:1. Run that with a 3.42 rear gear, and you'd have the perfect 5-speed. In fact, if I could have gotten something like that, I'd have skipped the T56 in favor of it.

Todd

badazz81z28
11-16-2003, 08:32:00 PM
I dont know what the heck to do. I was thinking T56 a bit ago but Im no metals guy. where the hell am I going to get a crossmember for a T56 for a 2nd gen. of course the T56 has a hydraulic set-up from what I have heard it is a pain to get the MC and the pedal setup right. And the big one is I cant find a T56 anywere. I have found some on ebay but dam Im scared to trust someone on ebay for such a large amount of money and not know its true condition. With the rating only being 450ftlbs I was thinking of a TKO II but again I hear about the gear ratios. I dont know what to do I freakin hate autos with their converter slip and all the other crap that goes with a auto.I want a nice manual trans that can handle the power but be not such a azz pain to install

mjoc
11-17-2003, 07:45:00 PM
If you are using the TKO Ii am because when you lok at the ratios on most t56 it is a double over drive. Where a t56 is about $2000.00 you can get the TKO for about $1400.00 and you don't need to find a hydraclic clutch or conversion kit bolts right in....where a tko is very close to the muncie four speed with a .56 over drive. In my car with 3.55 gears and 28 inch tall tires, it means a 1700 rpm @ 165 mph and 178 at 5500 rpm.. and still pulling... my car redlines @ 6800..

badazz81z28
11-17-2003, 08:13:00 PM
so do you feel the gear ratios between 1st and 2nd are fine? the TKO is having good feelings for me

ReD-DaWg-OnE
11-17-2003, 08:50:00 PM
man... this makes me want one! where did you test that at? The speed.

<font face="Arial,Verdana" size="2">Originally posted by mjoc:
If you are using the TKO Ii am because when you lok at the ratios on most t56 it is a double over drive. Where a t56 is about $2000.00 you can get the TKO for about $1400.00 and you don't need to find a hydraclic clutch or conversion kit bolts right in....where a tko is very close to the muncie four speed with a .56 over drive. In my car with 3.55 gears and 28 inch tall tires, it means a 1700 rpm @ 165 mph and 178 at 5500 rpm.. and still pulling... my car redlines @ 6800.. </font>



[This message has been edited by ReD-DaWg-OnE (edited November 18, 2003).]

Todd80Z28
11-18-2003, 07:22:00 PM
I'm calling BS on 178mph in a ZZ4-motored '70. Unless you've got at least 100 more HP than that thing came out of the box with.

Dyno runs don't count. http://www.nastyz28.com/ubb/smile.gif

75Camario
11-21-2003, 11:59:00 AM
Yep, I'm with Todd on this one. I think you'd have to have like 700 HP to force a bull-nosed sled like a '70 camaro to go that fast, wouldn't you?

Sc0tt_again
11-21-2003, 03:47:00 PM
mjoc - I'm sorry dude, but someone's got to put up the BS Meter.

Your bio says you've done 182mph. I'd like to see that.




------------------
The Plan: Merlin 540ci/650hp, Tremec TKO II, Moser 12 bolt, 13" Baer Brakes, PST front end, L-88 hood, complete M&H wiring, Autometer dash, 17" Fikse FM5.
Taking a $600 car and shooting for mid 11's on the street.
ETA - 8/01/04

Todd80Z28
11-21-2003, 09:39:00 PM
I've personally had my car to 153mph (calculated based on engine RPM/tire size, adjusted with my real world fudge factor), and it was "troubling." I was able to tell that I was not exactly in control of the vehicle- the aerodynamics were. http://www.nastyz28.com/ubb/smile.gif Top of 5th, and that was all she had.

I'd like to do it again, but the road I used has become busier. There was quite literally no one on the three mile stretch we used at the time ('96), and we "cleared" it via cell phone and spotters. Nowadays, people actually drive on it. http://www.nastyz28.com/ubb/frown.gif

Todd

Chuck78
11-22-2003, 04:09:00 PM
I was able to get my 2.41 rear 235/60/15 TH350 305 78 to bury the needle going downhill with the wind behind me once upon a time, in my younger and dumber years. once I hit maybe 135, it started to feel pretty unpredictable. I might have hit 138 or so. Normally, on flat ground on a calm day, the thing would have trouble breaking 115 - simply not enough power to break the aerodynamic drag. It would just creep past that slowly. The stock 220 ft-lbs and 170 hp just couldn't do it.

------------------

------------------
'71 RS/SS396 project: B-body/1LE 12" ft & TransAm 11.1" rr disc brakes, poly susp., 1.25" WS6 ft & 1" adjustable rr sway bars / 4 speed nodular case wide ratio Super T-10 / 3.23 posi rear / 81 Z cold air induction / searching for an L78 402, otherwise my 406 sbc will take it's place

aero80
11-22-2003, 09:00:00 PM
I ran my 77 1/2 all the way to redline on the 605 fwy where it's 6 lanes wide, maybe 7. It was 100% empty of traffic... it was during the Rodney King riots, and there was practically no one on the freeway. The 427 hit 6500 and the front end lift got downright scary. That was with the stock 3.73s and the wrong tires. I was stupid to run Radial T/As that fast.
I figure the math at about a buck fifty-five, or maybe even a buck sixty. I dunno.
I'll never go that fast on slow tires again. I had forgotten all about the speed rating, just saw an opportunity and nailed it, and just kept on holding that pedal down.

I figure I'm lucky, not smart.

------------------
Aero80

[This message has been edited by aero80 (edited November 22, 2003).]