1968 ???- 302 "off the line" acceleration

[daveS]

I tried out a J code CS GT yesterday that I am working a deal on. Its got the original carb on it. I noticed that off the line (from a dead stop), it does not really jump up and chirp the tires (which is what I was expecting).

I brought this up with the seller. He told me he had a "Holley made for Motorcraft" carb on the car previously and told me it was a lot quicker off the line. He offered to put it back on but it was leaking gas out of the floats, so he put the original back on. The transmission is newly rebuilt so I don't think there is an issue there.

Is there a kickdown mechanism or something that might not be kicking the car into first gear ?

Could it be that secondaries are not opening ?

Could it be just a mellower carb ?

With the orignal 4 barrel carb, was this car more of a cruiser or did it come from the factory able to "chirp" the tires from a dead stop ?

In general the car cruises nice.

Any thoughts here ?

Thanks !

-Dave

 

[teamlo]

The J code 302 was rated 230 horsepower. It's no barnburner! Back in the day, owners and the automotive press complained that the S-code 390 4V was weak, I can imagine the J-code is a step back from that even. If the car is not equipped with the GT equipment group, you're likely dealing with a 2.79 or 3.00 rear end ratio at best (GTs would likely have the 3.25). If the car has the stock Autolite 4300 4V and it's not tuned just right, well that is another matter as well, from what I am told.

Incidentally, I just had a J code engine built for my '68 GT. Basically stock with the exception of a Comp Cams 289 Hi-Po cam (hydraulic version) and roller rockers. I'm running stock exhaust and an Autolite 4300. It will hopefully be running on Sunday and I can't wait to drive it.

Terry

 

[robert campbell]

I agree with Terry. With 2.79 or 3.00 gears it is not going to smoke the tires! Even with 3.25 gears, it is not a race car by any means. If it runs good and cruises fine, then my guess it is just fine! The carb could have a stumble or flat spot that inhibits off the line performance, but that is correctable. Not a reason to distrust the engine.

Rob

 

[case12]

I had a 289 with 4 barrel intake and mild cam, automatic, and it still didnt jump off the line. It was a nice sewing machine motor - ran great and sounded good. I then went to a 2200 stall converter and 3.89 rear end.....some improvement, but not the 'smoking tires' I was looking for. I finally dropped in a 302 stroked to 347 (360 hp, 411 ft lb torque), and now I can create smoke like the spaceship Columbia taking off :grin:. A stock 289 or 302 is a good, fun reliable small block - it needs beafing up and other changes to get the low end torque you were hoping for....my two cents :smile:. Casey

 

[Midnight Special]

...I guess it depends on what you want to achieve. To me - chirping and spinning tires is a huge waste of time. My J code will only do that if I power brake slightly, but when you want to go - it goes! 0-60 times or standing 1/4 mile would be a better measure. Mine has 3:25s and stock Motorcraft 4v....

 

[robert campbell]

...I guess it depends on what you want to achieve. To me - chirping and spinning tires is a huge waste of time. My J code will only do that if I power brake slightly, but when you want to go - it goes! 0-60 times or standing 1/4 mile would be a better measure. Mine has 3:25s and stock Motorcraft 4v....

Tim,
But then there are people who love to "inhale the smell of Firestones"!!!! Just got my 1/2 inch in diameter smaller pulley for the "supercharger" and the methanol/water injection is due next week!!! From 8 pounds of boost to 12 pounds of boost!!! I bit more fine tuning!

Time to obliterate tires!!!! You tube here I come!!!

Rob

 

[Midnight Special]

Tim,
But then there are people who love to "inhale the smell of Firestones"!!!! Just got my 1/2 inch in diameter smaller pulley for the "supercharger" and the methanol/water injection is due next week!!! From 8 pounds of boost to 12 pounds of boost!!! I bit more fine tuning!

Time to obliterate tires!!!! You tube here I come!!!

Rob

...Indeed Rob! My son TJ is among them! Just check out how our driveway resembles an airport runway ;-) and the pine needles along the edge (sans bleach) that give "omnipotence" to a straight six! You and Casey however, have to try as hard NOT to chirp as we "stockers" who try TO....

;-))

 

[daveS]

You guys are an awesome resource. Thanks.

The motor purrs like a kitten, passes just fine and idles real nice...has a nice throaty V8 sound with flowmasters on it. I just recall driving a '66 GT coupe with a C4 & 289 + Holley 4bbl that "lurched" a bit more than this car....but maybe my memory is getting fuzzy .

The car really drives solid with all new front suspension and rebuilt tranny....smooth and solid enough for a road trip.

Cheers
-Dave

 

[Midnight Special]

...Sounds like a real sweetheart Dave! My J-code is the same as yours, Flowmasters in all. There are many unseen variables that can set these motors apart which aren't always apparent at first, but that doesn't mean there are flaws, especially with what you're seeing.

A high school buddy had a '65 coupe, 289, 4v, 4-speed that ran good & sounded REAL mean with a (God knows what) cam...but it could hardly pull itself out of bed! Conversely - My oldest son had a stock 302 2v rebuilt in a '69 coupe that smoked tires all day! I played hell keeping up with him in in a GT390 while chasing him home one day!

Rob can go on for hours on specifics, I'm sure, but if your 'J' is like mine - it will only spin a little at launch, but hang on! You'll be amazed how quick you get to 100!!

 

[teamlo]

I had a buddy in high school who had a '70 Maverick with a 302 2V in it. I am certain the engine was all stock. I swear that was probably the second fastest car I've ever ridden in. It was very odd, but the thing just flew.


Terry

 

[Mosesatm]

If you want to spin the rears in a big way I've found that nearly unused 20-year old Goodyear Eagles have no desire to hook up when pulling onto a busy highway with traffic barreling down. They just spin and spin!!!! I think it's time for new tires.

 

[Midnight Special]

I had a buddy in high school who had a '70 Maverick with a 302 2V in it. I am certain the engine was all stock. I swear that was probably the second fastest car I've ever ridden in. It was very odd, but the thing just flew.


Terry

...My first speeding ticket (January 1977) was in my friend's (mom's) Maverick! I flew to Torrance, CA to meet up w/ him to shoot pictures of trains... I was driving while he was shooting - 90 mph on the way to Barstow! The cop was real mad, but became compassionate and reduced the ticket to read "65" along with a stern lecture. I guess he figured we were more stupid and pathetic vs criminal...

 

[nfrntau]

Smokin party!!!

My first ticket was exhibition of speed.
Driving my sisters 69 Mustang 302, smoked them across an intersection. I was 16 at the time, Dad was maaaaad

 

[daveS]

Cool..thanks Midnight Special !

Here are a few pictures of the car....

 

[hookedtrout]

Based on the trailer with a hard top on it, looks like you might be a Jeeper as well? Nice CS.

Cory

 

[tomcwarren]

Looks like this one from Ebay:

http://cgi.ebay.com/ebaymotors/ws/e...00322930288&ssPageName=ADME:B:WNA:MOTORS:1123

Didn't sell at $19.600. Dave - do you mind telling us what you paid?

BTW, what is that color? Appears to be a bit 'oranger' than CandyAppleRed. Looks nice, though.

Tom

 

[Mosesatm]

Wow, look at that option list!

Are those original '68 headrests?

 

[daveS]

Based on the trailer with a hard top on it, looks like you might be a Jeeper as well? Nice CS.

Cory

No..no Jeep for me. The guy selling me the car has a Jeep...the pics were taken in his driveway. I'm getting the car shipped to me....should be here Tues or Wed. :grin:

-d

 

[daveS]

Wow, look at that option list!

Are those original '68 headrests?

Yep ! :grin:

 

[JohnnyQuest515]

Gorgeous car! If I remember the hp numbers back then were gross, now they are base on SAE net which are more realistic.

I would just check out the car and make sure everything is okay:
Fuel filter
Fuel Pump
Air Filter
Carb setting
Exhaust leak
TuneUp: distributor/coil/plugs
Basic stuff.

You might have a messed up spark plug!

Plenty of parts to make it go mo-faster if you want.

Enjoy!

Randy