Convert Trans to 4 Speed or 700R4 Automatic?

[bobbyd38]

Hi,
I have a 72 Chevelle Malibu that I plan to make into a 454 SS Clone/Recreation/RestoMod. Currently it has a crap Olds 403 in it, and a TH350, w/ a column shift. I want to swap in a new Crate 454 and Tranny, with a Console Floor shifter. I am undecided whether I want to convert to a 4 Speed Manual (possible C41) or an Automatic 700R4 w/overdrive. I would go for either, and my deciding factor is Labor/Time & Money.

Either way I have to add a new/refurbished console, rewire Neutral & Backup light switches, and restore the column to (No Shifter Lever) normal. At first glance it looks like I have to buy/add a lot of parts to go the Automatic route, and if I go the Manual route I have to add a clutch pedal/linkage etc.

Has anybody ever done either of these swaps, and if so could you please share your experience? If you have done both, which conversion would be less in Labor/time and money?

Thanks for your time,
Bob D.

[highlandlake]

Bob,
I've never done a four speed conversion, but I think it'll cost about the same as an auto conversion. Because finding the pedals, Z-bar, and a decent new or rebuilt shifter and matching transmission would take a fair amount of both time and money. The auto conversion has some small advantages, such as the smooth shifting and fuel economy you'd get with the 700R4 overdrive. But the new or new-looking console and horseshoe shifter aren't cheap. One advantage the four speed would have is that they seem to add more value to a car than an automatic. Nothing is more fun than revving the engine at a light, or catching 3rd with that much power.
Either way, you're looking at four grand plus to do either choice. Maybe more if you have all the work done by a pro. Maybe someone else here has a better estimate of the time and money for either or both?

[406Elcamino]

Awe come on 4 speed it. Be different. Besides a 700 isn't going to last long behind a 454 if you are hammering the gas hard often.

[mdcamaro]

Year One has all the stuff you need for a 4 speed conversion. You need to weld a plate for the Z-bar on the frame. A Muncie uses the same cross member and drive shaft.
http://www.fortesparts.com/ has conversion kits for Tremeric 5 speed overdrive.

[406Elcamino]

The bracket bolts onto the frame not welded. You can also find the pedal kits on ebay. Helped a kid at work do his not too long ago. Hardest part is working under the dash. His came with instructions on where to drill the hole in the firewall for the rod coming off of the clutch pedal.

[mdcamaro]

The factory welds the bracket. You can bolt on if you trust it.

[406Elcamino]

It is not welded on. It is shown in the assembly manual that it is bolted on. The holes are in the frame for the bolts.

[OZBIRN454]

It al depends on what you want to do with it. The 4 speed if driven nicley will bring better gas milage then a Auto for in town use. The 700r4 uses almost 35 horse power to drive it where the 4 speed is under 10. I have seen this in many of Dyno test at work. If you want a highway car the 700r4 will be better on gas but with a 454 I asume it will have some ass in ityou will want to race around town little tire smoking lets face it four speed is the way to go. If you plan on seriously racing the 700r4 will be most consistant.TCI has a nice 700r4 built to hold 450 horse pretty simple to hook up for about 1300+ a torque converter oh and you will need some sort of TV cable with a 700r4. I have seen alot of 700r4 if built right hold up to where a turbo 400 wont. 700r4 if built right can take alot of abuse. They had lots of problems with the factory ones thats why the bad rep.With all this said I always prefer a m22 munci rock crusher trans they a costly but take so much abuse and hold up.

[justinp01]

I just put a 4-speed in my automatic chevelle. It is very easy, just buy the $200 dollar pedal kit from ground up and get a clutch fork, bellhouse, flywheel and a clutch setup. The trans mount and the driveshaft are exactly the same.

A 700r4 cannot take the torque from a 454, a muncie can but you want to go with a M21 (~2.20 first gear) if you are going to pull up to the line with slicks on. But I have seen a Muncie case crack with a 454 chevelle and slicks coming off of the line.

Bowtie overdrive's sell 700r4's that they claim can handle 500 horse, but my uncle had one on a 502 and he blew the tranny 2 times (second came with warranty).

What you really need is a 5-speed tremec.....