61 replies to this topic

[Struggler]

Just as an aside, I have used a steel cased corona 4 speed before with great success. It was behind a supercharged and later turbocharged 308 in an LX. I often used to drop the clutch in top gear from a standing start. It never complained. It uses all celica ancillaries such as bellhousing, speedo cable, tailshaft etc so conversion parts are easy to get. The shifter is in built so no problems there, it even comes up close to the standard hole. As they are so robust there are heaps of them at the wreckers, expect to pay up to $80 for a good one. The majority of them have done little or no work as they were behind 4cyl engines in grandparent vehicles. I wouldn't hesitate to use another.

JMHO.

[TerrA LX]

I think there are two main types, early; no proviso for shifter, bolts to floor, and late (early to mid 70's and on) with shifter bolted to side of extension housing.
Early might be more suited if you prefer not to mod your tunnel but the later style is more reliable as the early ones tend to hook the shifter up with motor flex sometimes.

[TerrA LX]

Corona box is the 4 speed version of the Toyota steel case 5 speed if you want to know what they look like. Only difference is its missing 5th gear it the extension housing is where it lives so it is not as fat there.
Same length and same shafts so you need everything just like putting a Toyota (Celica) 5sp in.

[LhMusL]

This corona box is sounding like a great cheap box for mid-high hp, and its relativly easy to set up. What do they shift like?? What clutch were you using struggler??
Is this just another example of Toyota massively over engineering there gear boxes if they were originally desiged for a 4 banger.
Its interesting that they are so stong seeing that the 5sp boxes even though are good, wouldln't think they could take that kind of abuse. Would this be due to only having 4 gears instead of 5 leaving more room for larger gear sets???
Keep the info coming!!

[Struggler]

The clutch I used was a one off, Hilux or similar pressure plate and a paddle disc (ceramic on one side, copper on the other).

Yes they are the same looking as Celica 5speeds. The celica box is weak in the 5th gear, this usually fails first, taking everything else with it.

They shift fine, just like any jap box (getting new shifter bushings is relatively easy).

They do have straight cut gears, this makes them super strong, but a little noisy (I couldn't hear it over the engine though).

V8slrtorana, I will keep you in mind if I need any bellhousings.

[LhMusL]

Thanks struggler, So there the same looking as a Celica 5sp but are they the same internally just with the overdrive gear. If so would it be better to get the 5sp and just not hammer it in 5th???? and drag and race in 1-4????? Or are they Helical?? (non straight cut) in the 5sp therefor not being as strong???

[LhMusL]

Bump

[Struggler]

Sorry guys, I didn't realize I left you hanging !!

All Toyota boxes have straight cut (or as close as straight cut as possible) gears

Yes I believe the Corona 4 speed is the same as the CAST IRON (not alloy split case) 5 speed Celica box. The problem is that the 5th gear is an afterthought. 1600 Celica's break the overdrive cruising at 100 kmh, imagine what a 308 would do to it !! By all means try the Celica 5 speed but beware !!! All the Celica 5 speed boxes I have seen fail start off with a 5th gear failure, then all the broken bits get caught up in the good gears and ruin the box.

Like I said earlier, I used a Corona 4 speed behind a supercharged, then turbocharged 308 for over a year without any problems. This included many standing start, 4th gear burnouts (yes - put it in top, rev it up and dump the clutch from a stand still). I wouldn't hesitate to use one again. These boxes are quite popular in Rotary drag racing circles (as someone else has already pointed out) due to their availability and strength.

Yes, first gear is quite low (lower than a 6cyl M20) at 3.58:1, first and second gears are slightly lower than the Celica 5 speed, third and fourth are the same (same as V8 M21 as well).

John, you are correct, the disc was Hilux based, pressure plate was Holden based, sorry for the confusion.

Hope this helps.

[LhMusL]

THanks for all that struggler
Who would you recomend for Bellhousing, Hydr clutch setup, X-member etc
CRS, Dellow still do them, got Mal Wood looking into it. All around the same price, just wondering who to choose!
This is of course if i can't get one on ebay

[LhMusL]

ALso what year corona's have these boxes??? and what is the code: T40, T50, W40, W50.
Not having to much luck finding one at the moment, anyone know somewhere in Vic who would have one? If not ANYWHERE were i can get one
Also read somewhere else that they have 2 shifter positions, might go the further forward one as then i might still be able to use the bench seat?

[LhMusL]

bump

[Struggler]

Try V8slrtorana first and keep it in the forum. Failing that CRS or Dellow.

Never had a problem finding a box. Most wreckers don't keep them as they are not popular (they never fail!!). Find someone wrecking a 4cyl (jap engine, NOT starfire) Corona with a steel case 4 speed and help yourself. There are complete cars on eBay for $100

I am unaware of two different shifter positions. This may be true but I only ever came across one.

Hope this helps.

[LhMusL]

Thanks guys is this one??
E-bay Kit

Looks like its got most of the bits i need, but prob go a better clutch, anything else i need??
Cheers v8slrtorana what bolt pattern are your belhousing to suit? Think i need turbo as i'm looking at 304's to put it behind.