use of cobra 4v mod motor in GTD?

jimbo · 03-01-03, 07:03 PM

I don't know if this has been done. It was discussed earlier on in several threads. I think the general feeling was that these are MUCH larger in dimension than the pushrod engines, very expensive, aftermarket stuff is sparse compared with the pushrod engines, and at the end of the day they don't make a whole lot more power, if any. I am not aware of anyone on the forum who is dong this.

Howard Jones · 03-02-03, 12:14 AM

Jim just said it all. I have a GTD and I think I would bet money that a modular motor will not fit without a great deal of reengineering of pretty much the whole rearend of the car . The gearbox would turn into a project also! There is just no reason to do it other than if you really want to. IF you do then get a blown up one from the junkyard and see if you can make it fit. Try and keep the centerline of the crank as low or lower that the 5.0 motors. The GTD chassis mounts the motor fairly high as it is with a 302. Some of the really quick GTD's have done a lot of work to get the motor lower. You know these things cost a lot of money as they are without all the extra electronics, exaust system which itself would be a major project, chassis mods, gearbox fit,etc. One more thing, the height above the motor is very limmited also, Just enought for a Eldebrock RPM performer and a holly on a 302. With a very short airfilter I have about 3/8" between it and the rear windscreen.

journeymanjoe · 03-02-03, 12:57 AM

Anyone know of anyone who has put a 4 valve modular in a GT40, specifically a GTD? [img]images/icons/confused.gif[/img]

meat · 03-02-03, 09:35 AM

Well, a picture is worth a thousand words, and I've always used alot of words... [img]images/icons/grin.gif[/img]

Also, the exhaust ports appear to be at a radically wrong angle.

I'd love to see it done...But I'm not going to do it!

Your pal,
Meat.

jimbo · 03-02-03, 10:24 AM

Wow. I knew there was a significant difference, but the picture shows it more clearly than any description.
There are at least two GT40s running around with 4cam Ford Indy 256 engines in them, which isn't 4.6 liters but isn't that far off, either. In the one I saw, the heads were swapped side-to-side to put the exhaust ports inside the cylinder Vee, so the exhaust system does not look too much different from that of the pushrod engine car. There are a limited number of 4cam Indy engines around, though, and at 35-45K a copy there are probably better choices. I didn't hear it run, but reportedly the sound is memorable. Photos of Jim Toensing's 4cam GT40 are in David Hodge's book, I believe.

Ron Earp · 03-02-03, 10:56 AM

RF had some pictures of a 4.6L install in one of their cars at one point. A serach might turn it up, Robert indicated it was very difficult.

R

journeymanjoe · 03-02-03, 03:31 PM

Thanks guys! i just thought it might look pretty trick in there, thats all. when I do it I'll probably run a 347 anyways.
[img]images/icons/tongue.gif[/img]

M.B · 03-02-03, 05:15 PM

One of the ideas with the 4 cammer, was to have the exhaust in between the cylinder banks...

Several 4 valve modulars has been put into replicas.
Even a Swedish KVA has one..

1027 had a 4 cammer at some point..
103 also, but i think i recall it is changed to a more proper engine..anybody ?
109 had one at some point, might be out of it again..anybody ?
No car had one in the 60s..(GT40)
[img]images/icons/wink.gif[/img] [img]images/icons/wink.gif[/img] [img]images/icons/wink.gif[/img]

John Schneider · 03-03-03, 01:48 PM

Here's a lin to pictures Wayne Presley posted. Sure looks good! http://www.gt40s.com/cgi-bin/ultimat...c&f=1&t=000136

Hershal Byrd · 03-03-03, 02:07 PM

If you gotta try it be sure and wait for this new crate motor from Ford. Interesting
concept by Ford. http://www.allfordmustangs.com/artma...icle_111.shtml

Hersh [img]images/icons/smile.gif[/img]

journeymanjoe · 03-03-03, 05:45 PM

Thanks again for the replies guys! That Maserati looks great in there, I bet he got some grey hair trying to make his exhaust system! (have to remove exhaust every time valve lash needs to be adjusted, or just never rev it up, eh?)
[img]images/icons/grin.gif[/img]

journeymanjoe · 03-03-03, 05:50 PM

P.S. I wonder who made the adapter plate on that maserati setup and how in the heck did he set up the clutch to make up for the thickness in the adapter plate?
[img]images/icons/confused.gif[/img]

jimbo · 03-03-03, 05:53 PM

GT40 #103 had the 4cam Ford Indy engine when I saw the car in January of this year. The owner indicated that the early GT40 tubs had originally held Fairlane 256 CI pushrod engines, which mountings were similar to the Indy engines, so that the swap was not too difficult. Fitting the 4cam engine into a later tub would be harder. The car also sports its' original ZF transaxle. Interestingly, when it won Daytona in 1965, I believe it had the Colotti gearbox- maybe one of the few instances in which a Colotti held together long enough to finish- and win. [img]images/icons/shocked.gif[/img]

M.B · 03-04-03, 12:37 AM

Thanks for the info on 103, Jim !
So, then there is at least one out there with an 4 cammer..

Those "Fairlane" engines were actually early Indy engines..
Pre 4 camm etc...
They all are descendens to the "Fairlane" engine..
It was originally sold with the Colotti box..
ZF´s were not available before early -65 something.March-April ?
[img]images/icons/wink.gif[/img]

40 Bud · 03-04-03, 12:43 AM

If you like "unique" check with Bob Lacey at CAV. One of his customers installed a 4 cam Maseratti engine into one of the early space frame CAV's. I would love to hear more about it.

RD40866 · 03-04-03, 08:56 AM

Marco, right you are. The "Fairlane" series engine has the same derivation of cylinder block as the 255 4 cam indy engine. The ndy motor was never designed to be a torque beast, but rather to generate maximumhorsepower in a very narrow rpm band. It was never a "good fit", application wise for the '40. It did have a strong aluminum block with pressed in cylinder liners; one that allegedly was used together with the Gurney heads on many GT40s. Remember at that time Ford had no other aluminum block in production; it was the iron age in Dearborn.

M.B · 03-04-03, 01:53 PM

Latest 4 cammer even had Turbo....

1963 Indy engine (very early)
The Fairlane 260 was used as a basis.
Also because the developers saw the potential and it was also the engine nearest to the 4.2 litre limit (256.2 cubic inch)
Alu block
alu heads, basically like stock(design). larger valves etc..etc...
3.76 bore compared to 3.80(stock)
Same stroke....
Forged billet crank,standard rods,dry sump and the recently developed transistorized ignition.
180 exhaust, wich showed inproved extractor effect particulary beneficial in mide range torque.
Gasoline and webers proved in favour of carb/alkohol and hilborn injection.(desicions not jusp HP factors mind you..)
The pushrod engine were favoured over the twin cam heads at the time...
Problems that were taken care of:
Pistons
Head gaskets
Valve gear
Carbyration
Installation
48IDA, then 58”IDA”´s were chosed as being given best results
They got it running very well.
Some mods, got into production 289....
And into some 221, 260 mods too...
Even the Y blocks got some...
Then came
1964
Further developments(ongoing developments in detail took it place continously of course..)
Injection, 4 camm.
Very similiar to -63 blockcastings, from revised 289 fairlane patterns....

Up to date and further developments and mods resulted in the Late small block GT40 engines, TransAm tunnel ports, 302W,Boss 302s etc etc...
[img]images/icons/grin.gif[/img]