Original Road Car Engine specifications

Ron Scarboro

GT40s Supporter
Supporter
Is there a resource that would outline the parts included in a GT40 road motor if I were going to try closely replicate the original specifications?

It was listed in Ronnie Spain's book at 380bhp for a 289ci in a Mark I

I'm looking for
Cam specs
Head specs
Alternator parts numbers
Etc...

I've tried to search, so if there is a thread for this a link would be appreciated.

Thanks,

Ron
 

Ron Scarboro

GT40s Supporter
Supporter
I think the first thread has lost a lot of the attached pics.

Graham, thanks. They somehow found 109HP from the 271 on the HiPo engine.

I figure heads and cam had to be involved.

Anyone know the cam grind?
 

Scott Calabro

Supporter
Is there a resource that would outline the parts included in a GT40 road motor if I were going to try closely replicate the original specifications?

It was listed in Ronnie Spain's book at 380bhp for a 289ci in a Mark I

I'm looking for
Cam specs
Head specs
Alternator parts numbers
Etc...

I've tried to search, so if there is a thread for this a link would be appreciated.

Thanks,

Ron
Ron,

Sorry, I can't speak to original specs but my 289 made 385 HP on the inertia dyno with 4 into 1 headers. It must be somewhat of a similar spec. I used...

11/1 static CR
Holman & Moody C30Z solid cam
Crower cool face lifters
Ross flat pistons
5.4 Rods
Stock 66 289 crank in a studded and main girdled block that also had a valley girdle.
High press/volume OP
Moroso RR oil pan
Studded Eddie RPM heads with 1.5 roller rockers
Eddie WP
4 Spanish 44 IDF's

The car weighed 2120 lbs fueled and was a rocket.

http://m.youtube.com/watch?autoplay=1&v=CiY0reGwuzo
 
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Scott where could i buy the Holman Moody C30Z cam from? I am also looking at a original build using a 302.

Cheers
Dave
 
Is there a resource that would outline the parts included in a GT40 road motor if I were going to try closely replicate the original specifications?

It was listed in Ronnie Spain's book at 380bhp for a 289ci in a Mark I

I'm looking for
Cam specs
Head specs
Alternator parts numbers
Etc...

I've tried to search, so if there is a thread for this a link would be appreciated.

Thanks,

Ron
I think with modern cam profiles and cylinder head technology you could have the same horsepower without the harshness of a race spec motor. Nostalgic cam grinds are exactly that.

Bob
 
I had an period Gt40 engine some years ago (Alan Mann) and the spec was this; HiPo block and crank (with grooved mains), HiPo rods with TRW hi comp forged pistons (12:1), ported heads with 1.9/1.6 valves, 'Le Mans' cam, 48 IDAs and Aviaid pan. This is pretty close to the spec Shelby used for his customer race engines.
 
I think the first thread has lost a lot of the attached pics.

Graham, thanks. They somehow found 109HP from the 271 on the HiPo engine.

I figure heads and cam had to be involved.

Anyone know the cam grind?
The "race" engine developed 380 bhp but the road car engine was quoted at 335 bhp (as per the road car sales brochure). I think it is likely to have been closer to 305 bhp.

Cam was the standard Hi-Po one.

Regards,


Graham.
 
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This might help you.....

Andy
Andy- thanks for that pdf,--it has specs I haven't seen in official Ford docs.

They give 375 HP with the Le Mans cam and later in the upgrade portion reference a block with 4 bolt mains in the center 3 positions. The part number given for the block is not the standard casting code, just "375063-S". A bit further the doc. mention a crankshaft with revised weights, part nr.. 377436-S". I thought that the Boss 302 was the first 289/302 with a 4-bolt mains block and that the only difference in the HiPo crank was that it was checked for hardness. Did Ford come up with a precursor to the Boss 302 block and a special 289 crankshaft and use different part number designations for them? JacMac?
 
Gentlemen,

The 4-bolt 289 block is XE 136505. It's lineage is the 255 Indy motor, the XE 136505, 1968 302 Tunnel Port, 1969-1971 Boss 302.

The book 'Ford Small Block V8 Racing Engines', Chapter 5, by Des Hammill covers mechanical specifics of MK I GT40 engines. Very informative.

(Perhaps a colleague more computer saavy could refer an easier link.)

It 'Googles' easily.

Steve
 

Attachments

That article raises a few questions?
The bob weight for balancing is listed at ~760 grams and info for flywheel balance factor shows 9.8 oz / in @ 180° 26'... if that is correct then the counterweights must have been heavier or piston/rod assy much lighter...... mind you all this data could be a 'moving target' as development took place first & paperwork later in many cases.
 
Ford Motorsport with the latest Boss 302 block, Dart in alloy or Iron, Mitchell, couple of Asian based versions, plus a few others, choice is much better than it ever was back in the 60/70's last century.
 
Lew florence cobra team driver for 1.5 years told be he had (on occasion) a 289 hi-po with a racer brown cam, modello heads and a mickey thompson stroker crank. The displacement came out to 340 cubes. He blew one up at Bridgehampton. The car was yellow #66. He said they found pieces of piston in the carb after the tear down. This engine had an additional set of springs and plates on top of the lifters under the intake manifold to help things stay together at 9,000 rpm. The inside bottoms of the cylinder walls were notched 3/4 of an inch to clear the rods. It was o.k. to cheat unless you got caught! I had one of these engines for about 20 years. It was in a c/gas front engine dragster. 1964 289 block. I sold/traded it to a friend in the early 90's who still has it in a box.
 
Gentlemen,

The 4-bolt 289 block is XE 136505. It's lineage is the 255 Indy motor, the XE 136505, 1968 302 Tunnel Port, 1969-1971 Boss 302.

The book 'Ford Small Block V8 Racing Engines', Chapter 5, by Des Hammill covers mechanical specifics of MK I GT40 engines. Very informative.

(Perhaps a colleague more computer saavy could refer an easier link.)

It 'Googles' easily.

Steve
I can see no difference between that block and the 302 boss block I have here, aside of the screw in core plugs its identical. Its obvious from the picture where the boss engine was conceived. The big advantage this would have over any sportsman or svo block would be its weight , I weighed my boss block and its as near as makes no difference the same as a stock 302.

http://www.gt40s.com/forum/gt40-tech-engines-induction-exhaust/40865-engine-weights.html

Bob
 
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