using a Big Block vs Small Block

I'm looking into using a BB as I've been offered a servicable original 427 side oiler.
Are there any major issues I should be aware of if contemplating using a Big Block ?

for example:
- Will a 427 BB still mate to a ZF gearbox ok ?
- will the ZF be up to the job ?
(I think trying to get a hewland is out of the question)

I have read that the extra weight from the big block makes it more practical to use a small block motor most of the time. I just want to evaluate my options before I jump in or out of this 427 though.

Cheers,
John.
 

Ron Earp

Admin
Some companies do not support mounting of the Farm Engines in the GT40. However, you can definitely do it since they do fit and all replicas have a somewhat similar structure. The ZF will work, and it should be good for the power since they are commonly used in this application.

Jerry Jansing has one in his Roaring Forties GT40, and there are others running around too. But, considering you can get 427+ inches from a Windsor stroker, in a smaller, lighter package, the FE is sort of redundant. IMHO of course.
 
John! I would have used a G50 box instead of the ZF because none of this boxes will stand if you are going to race. But as Ron suggested it will work if you are careful and not jumping off the cluch at 7000Rpm, warm tyres. Dont push to hard on low rpm. Also if you consider the cost you will get a G50 for less than syncrorings for ZF and why waste money.
today the ZF is hard to get and I spoked to a guy that has 2 boxes for sale but they need some care since the guy has shotblasted them and painted them in silver. Some people does seam to destroy more than renovating but that is my oppinion. Anyway I found another box so if you need one I can pass you the contact of the shotblasted ones. But as I said they did not look fresh from outside and check them properly inside because they are expensive to renovate. I had one 15 years ago and it was pretty worn in the ring and pinion. We are doing a side project in making the 4.22 and 3.7 ring and pinion for the ZF but it does not have high priority.
 
the 427 is a heavy powerful engine so Ford designed its own T44 transmission because nothing else was capable to withstand the torque.things has changed now maybe but take a lesson out of this.
 

Howard Jones

Supporter
I think that if you find out the weight difference between a alum head winsor and a iron head 427 it will make the choice for you.

Think power to weight ratio.
 
I think you will find for similarly configured engines (aluminum heads and intake) that the weights are not that different. As I have noted many times, take a look at the 452 CI FE here at 503 lbs:
427 FE

Versus the 351 based 427W here at 467 lbs:

427W

Both were measured on the same set of Longacre scales. The 427 FE does fit in a CAV GT as seen here:
IMG_0201.JPG


The FE engine is slightly heavier (36 lbs) and more expensive to build, but can be built to larger displacements (~50 CI larger) because of the extra deck height and bore spacing.
 

Ron Earp

Admin
But, for the money on the FE you could have an aluminum Windsor Dart block, get more displacement, and a bigger weight difference.

R
 
I'm taking my CAV to Kinetics next week to install a 510" all aluminum FE tunnel port. I'm using the ZF 5 speed trans axel and Kinetics says that I can break it almost at will, however this is the combo I wanted and I don't plan on racing it. That pic of the 427 engine in the GT40 is very cool. Personally having a GT40 with a small block is like having a girlfriend with small breasts, its OK but big ones are more fun, Wayne
 
Wayne, what a classic statement /ubbthreads/images/graemlins/grin.gif

Well, the deed is done. I have brought it.
Its an original side oiler on original bores (not rebored) with original heads.
Now I need to go do some digging to decide what state of tune to take it to /ubbthreads/images/graemlins/tongue.gif

I accept the ZF may be weak, but as said there aren't many other options. Getting hold of a T44 or a 600 box is not really an option as they are so rare/expensive.
Goran, I have a lead on a couple of ZF boxes already, but thanks for the offer of the info for that shotblasted one.
I'd be interested to hear what sort of money they want for it (via pm if you prefer). If they fall through I'll give you a mail.
I will consider a G50 box, but ideally I'd like the car to be as original as it can be. I know the ZF was used initially with the 427s, even if it did break a lot...
I also assume the G50 will break quite easily, just be cheaper/easier to repair, right ?

That picture is superb. If you have any more of the 427 in a mk2 please post them /ubbthreads/images/graemlins/wink.gif

Cheers,
John.
 
Why not consider the 4 speed Porsche 930 turbo box (3.3 litre '78-88)? Reputedly unbreakable and fairly cheap. The t-44 was only a 4 speed box (recased toploader internals) so its in keeping with the Mk2 ethos. There was a thread showing a repro t-44 box recently; that might be available as well.

Colin Artus
 
Colin,
I do recall seeing the thread about the repro t-44, but also thought there were only a limited number of them being made and they were all accounted for. I'd love a t-44 or LG600, but I doubt I'll get one.

I'll have to investigate the 930 box. Is it a better choice than the G50 strength wise ?

Assuming I build the engine to give ~550 to 600 bhp and a similar figure for torque, what is my best choice for strength / availability ?

Goran,

the ring and pinion thing. Is this to better match the gear ratios to the 427 ?
What sort of money do you expect these to be, and available in what sort of timeframe ?
I notice your signature says you have an LG600. Is the ZF your after for a different engine to the 427 ?
Or is the 600 box for sale... /ubbthreads/images/graemlins/smile.gif /ubbthreads/images/graemlins/smile.gif /ubbthreads/images/graemlins/smile.gif /ubbthreads/images/graemlins/tongue.gif
 
John

Everything I've seen/read says the 930 is stronger than
the ZF or G50. The question is whether you can live with 4-speeds. The MK II's were geared low so they could reach
220 mph...but that gearing would be a dog for most street
work.

MikeD
 
I hate to pipe in to continue on the trans issue - but I seem to recall that RUF had come up with a 5spd version of the 930 4spd. Supposedly they added a fifth gear and had all the ratios spaced properly. Anyone recall such a thing? No doubt it wouldn't be cheap since RUF has always taken a money-be-damned attitude, but their stuff is the cat's ass if you still like porsches.

Mitch D
 
The RUF boxes are a good bit different, and probably very expensive. They atleast have longer shafts, and different castings.
 
I have a new T44 that I might sell, started to out in my CAV but it is to expensive for a kit car. Also just bought a new tennant tub for speculation and might let the tub and T44 go as a set. Kenetics says the porche 50 gear box is strong, but a bitch to make work with frame cutting, fabricating linkage, etc. Kinetics number is 734 595 7593, ask for Chris, ex Roush people, never to busy to talk to you, Wayne
 
John, if you are getting a standard bore side oiler, sell the block. They will go for 5500 to 6000US. Robert Pond will sell you an aluminum block capable of going to 4.310, looks identical to the iron sideoiler for 4500US. You have a better product (FE's like to run hot because of the thin cylinder walls), sell the crank and rods go with after market billet crank and rods, will look original, you will have a better engine, save a little weight, Wayne
 
Any info on the Ford GT trans? Looks big and heavy to me, but I bet it can take lots of torque (Saw a writeup with a Ford GT doing 10.8 1/4 mile runs). Now that takes torque and HP considering it is over 3200 lbs.
 

Ron Earp

Admin
Was that the same one in MM&FF? They did a good job there and didn't even get into the possibilities of turning up the boost with a pulley!
 
Ford GT transaxel is a Ricardo 6 Speed. I was offered one out the back door of Ford for 35K. Don't know if that is a fair price or not, Wayne
 
John on Ebay #7979594265 is a Pond aluminum block you can get a description of what it is. We big block people with farm tractor engines are out numbered we got to stick together, Wayne
 
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