Z/28 vs. Tunnel Port 302

[2112]

https://www.caranddriver.com/archives/1968-tunnel-port-ford-mustang-vs-chevrolet-camaro-z-28-archived-comparison


Lots of good pictures

[Wedgeman]

Great Article...

[roddster]

  I know I have that magazine.  I don't remember, did the Tunnel Port toss the rods or what?

[shelbydoug]

  I know I have that magazine.  I don't remember, did the Tunnel Port toss the rods or what?

At 7,000rpm it shouldn't have. That was a four bolt C8FE Boss 302 block, or what became a Boss block and the problem with that engine was that the power band was up over 8,000 rpm to make it pull under race conditions.

In fact I think the number was 8,200+...gaboom!

[fthlflyer]

Reviving an older thread to ask a question: Does anyone know what the extra breather and tube on the Mustang's passenger's side (behind the battery and next to the solenoid) goes to?

Thanks

[crossboss]

  I know I have that magazine.  I don't remember, did the Tunnel Port toss the rods or what?

At 7,000rpm it shouldn't have. That was a four bolt C8FE Boss 302 block, or what became a Boss block and the problem with that engine was that the power band was up over 8,000 rpm to make it pull under race conditions.

In fact I think the number was 8,200+...gaboom!

No, not really. No engine failures on this one. This is a real Tunnel Port experimental engine:
"Well, yes, this is your regular 12.5 to one compression ratio, dry deck, tunnel port 302," allowed Ford Man still a bit defensive from the tire discussion. "How many do ya want?" Man, just the name tunnel port makes us stand at atten­tion. It's really a simple idea but only Ford had the initiative to do it. Instead of trying to crowd the intake ports between the push-rods like everybody else, Ford just made the intake port as big as they pleased and then ran a little tube down through it for the pushrod to move inside of. A great idea. This particular 302 had a fairly tame (by race standards) camshaft and a dual-point distributor without the benefit of transistor ignition. An 8-quart road racing oil sump finished off the package."

[crossboss]

Also as noted in the article, the Camaro was the better street car, and Mustang was the better race car.

[FL SAAC]

Thanks for sharing

[shelbydoug]

Reviving an older thread to ask a question: Does anyone know what the extra breather and tube on the Mustang's passenger's side (behind the battery and next to the solenoid) goes to?

Thanks

It depends on who set up the engine which I doubt seriously could be called stock.

It may be a breather for the oil pan. At some point in the development of the Boss 302, the valve covers were using drain back tubes to the pan.

Oil sump pressures are a significant consideration on all engines and a crossover between a race and a "street" engine, that factor can be tricky or just a little controversial.

Race engines in the day were just vented to the atmosphere. Today if you can get it balanced correctly, 10-12 inches of vacuum to the pan helps seal the piston rings to the tune of something like 25hp. That requires a closed venting system which depending on the kind of racing you are doing can be difficult to balance correctly but is doable.


As far as the rev limits and the grenading tendency of the Tunnel Port engine, since I wasn't there in the day, I have to rely on the press reports and reviews of the time commenting that "the drivers" claimed there was no power in the T/P until about 8,200 rpm's at which "every single" Ford assembled engine blew.

It isn't an argument on my part, just a comment on why "the race teams" claimed the entire season was a wash.


One thing that I was looking for in the pictures that I didn't notice was the serial number stamping into the car, i.e., whether or not it showed  the D engine code.

As far as I know, which again is not first hand and subject even today as controversial, how many "genuine" D T/P cars were manufactured and how many were just restamped Shelby T/A cars to comply with the rules.

I personally kind of doubt anyone would take seriously that the number produced would  comply with the minimum necessary.


Thinking back on reading some of these types of review articles, I seem to remember "some" mentions, here and there, of reviewers questioning why "these street looking tires" would feel so sticky to the touch and why they all seemed to have an extra "S" in the molded in identification number?

At some point someone mentioned special test tires made by Goodyear that had soft race rubber compounds. Interesting to review now that seemingly no one talks about them anymore and certainly no one these days talks about having them "re-manufactured"?


All in all, a very interesting artifact article of the day but anyone is going to have a really tough time convincing me that both of these cars are not "factory 'ringers' ".

The quote about the Mustang Tunnel Ports by the "Ford Guy". "of sure, how many do you want" is typical smoke screen stuff of the era.

Even suggesting that either of these cars somehow came directly off of a production assembly line is just plain ludicrousness.

[98SVT - was 06GT]

I know I have that magazine.  I don't remember, did the Tunnel Port toss the rods or what?

Titus/Bucknam won out of the box at the Daytona 24 hour. They were 64 laps ahead of the second place Penske Camaro. Porsche prototypes were 1-2-3 at the finish and Titus stuck the 4th over the line Mustang right in their "ad photo".
Titus popped the first engine in race 3 - After Titus didn't win race 2 Ford had demanded that SR (SR = Shelby Racing Inc - Since mid 67 CS was no longer an independent Ford backed company but a contract race team working under Ford's dictates) not even open the engines and run them as received from Ford. If you remember this is the same stunt that Ford pulled in 1965 when they demanded SA swap their engines for Ford built ones just before the start of LeMans - head bolts failed. They took a failed TP engine apart and found it still contained casting sand. One failed on the pace lap. The onsite Ford engineer accused Titus of intentionally over reving the engine. Titus grabbed him and stuffed his head through the drivers window and pointed out the tattle tale on the tach was at 4,200....
After RPM limits by Ford that were to low to win any race and 4 failed engines Titus told CS at race 12 he would not be back for 1969. In typical CS you can't quit you're fired style Titus ended his driving for CS. Ironically Titus bought Jon Ward's Camaro AS car for the final 68 race - they swapped body parts to make it look like a Firebird but had little other prep time - the engine blew.
Interesting - Sam Posey as the test driver. He is who CS was speaking about when he made his comments about rich kids buying rides rather than coming up through the ranks.

Link to homoligation papers - https://historicdb.fia.com/car/ford-mustang-1968-gp-ii-302

[pbf777]

Also as noted in the article, the Camaro was the better street car, and Mustang was the better race car.

     This was the greatest magazine comparison test ever! The next best was the '65 Pontiac 2+2 vs. Ferrari!

     But at the time, for those with automotive familiarity, it really was solely entertainment, as all concerned understood that that as was being presented was not probably representative of what was in the showroom.   And although the Ford certainly appeared the more exotic  , which was understandable when one considers that period of Ford's racing history and the products they had developed to that point; but don't think that GM showed up unprepared.  After all, consider that the DZ-302 engine basically shared the same engine block (same bore and deck-height of 9.025") as that of the 327 and 350 cu. in. engines, but with a 283 crank-stroke swap for the reduced capacity.  So, particularly since the article did reference how much more "street friendly" with greater lower R.P.M. torque that the GM product presented (as I recall), do you suppose they showed up with only a 302?   

     Yeah I know, the article stated that they "checked 'em" (P & G ?), but racers have been cheating past that for decades, you think the GM engineers couldn't have figure it out!   

     I dunno................ But remember it's just entertainment, just don't get to serious about that which we'll never know.   

     Scott.

[tesgt350]

Reviving an older thread to ask a question: Does anyone know what the extra breather and tube on the Mustang's passenger's side (behind the battery and next to the solenoid) goes to?

Thanks

Possibly to vent the Oil Pan Sump?

[Royce Peterson]

I think it's typical of Ford to make only a couple of examples while GM makes thousands of them and sells them to anyone. Granted the Z28 was never a hot seller but compared to the tunnel port 302? Or even the Boss 302? The Z28 might be from GM but damn! It was a great car.

[shelbydoug]

Reviving an older thread to ask a question: Does anyone know what the extra breather and tube on the Mustang's passenger's side (behind the battery and next to the solenoid) goes to?

Thanks

Possibly to vent the Oil Pan Sump?

I've seen weirder stuff then that. We will never know though exactly what the thought going on with it was. I've never seen anything quite like that and there isn't anything else that needs venting.

Mountain motor experiment maybe?

Personally I think that the cross over tube from valve cover to valve seen on the B2 T/A cars that was adapted from the NASCAR boys engine
builds is strange as well but amongst the simplest to deal with.
I should add that those things have open breathers on them and will spill on road race set ups.

The current use of a closed vent and a scrapper tank is good thinking but I don't know the issues that it has with any kind of endurance racing.

I use that set up and find mine mostly full of water with oil droplets mixing with it. It's a really yucky mess to clean out.

[fthlflyer]

I agree and suspected it to be a crankcase vent of some type, but that seemed excessive with dual breathers on the valvecovers. Blown alcohol motors don't need that much venting. . .

I'm wondering if Ford didn't use something off the parts shelf from a truck or industrial application. . .