If i remember correctly from a old Road & track mag the boss 429 ran a tenth better than a 71 demon/duster 340. like 14.40 to the 340's 14.50's. they were not very fast for the engine cid to weight!!

Maybe it was the size of the ports that killed the velocity and thus the VE? I mean check out the size of those ports

They were huge, still a slow car in stock form for cid to weight, But i'd love to own one !!

Boss 429's are cool engines, the first Boss 429 Mustang (an orange one nearly identical to the one pictured racing)was a slow toad. The owner and I traded cars for a day (mine was a 67 Hemi Belvedere 4 speed). To say the Boss 9 was "weaker" than the Hemi would be a huge understatement, in fact the cars owner didn't want to give me the Hemi Belvedere back!

The next one I drove had been "breathed on" a bit but still looked and ran stock for the most part, bigger cam, no smog pump, and some intake work made a BIG difference.

It ran more like a Hemi, quite fast.... not exactly stock but looked it to the average guy and it was much more fun to drive!

Engine same car

Kaase has some sweet cylinder heads for these now that totally rip. Best part is, the stock intake and exhaust manifolds and vc's fit.

The problem ford had with the boss was it was a detuned nascar motor. With the big valves and ports ,small cam smog equipment it had no low - mid range for street driving. To help they took off the 780 cfm holley and put the 735 cfm off a 428 cj. That helped but did nothing for the bad rap the motor was getting in the hp department. A friend of mine that was a engineer at fords at the time had a boss and was very dissapointed what they had done to the combo. He took his apart and put more compresion in it better cam and headers and 4.30 gears and the car was a hole new animal.

I always liked the Boss 429---that & the 427 SOHC motor. They were 2 of Ford's really good ideas, IMO but they were never street motors. even the racers back in the day gave up on the Boss & in early P/S went back to the SOHC motor as it performed better & was a true hemi-head design.
I have a buddy that was all hot for building a Boss 429 recently & after some discussion, research & evaluation he's building a SOHC motor instead. (personally I'm certain I'll still beeat him with my Hemi )

I raced a few back in the 70's and had no trouble with my stock 440 Charger R/T running hi 13's. They were good matches for 383 mopars and 396 Cevelles. If that 429 is a numbers matching car, I'd take it home and watch Barett-Jackson.

Something I read/was told/fantasized/programmed with when abducted by aliens:
The whole deal was the 7 liter thing in NASCAR, the GM 427, the Mopar 426, the FOMOCO 429, all with these ungodly huge ports would have easily fed a 500 inch plus motor and made all kinds of ponies, but the limit was 7 liters.
Was this a beer dream, or do I make sense?
C

thanks for the compliments guys.

scott is that boss 9 in the spokane area?

the mustang ran a 13.06 on that pass. it was however running 12.9s most passes. it was really hot the air was 4500+ feet. im sure its a mid-low 12 second car on the cost in good air. he says its basically stock with a little bigger cam and headers and 2 4 barrels.

Check out Jonkaaseracing.com. Jon is producing new boss heads, intakes and valve covers. Neat thing is they bolt right to a 460 block and use standard 460 head gaskets. He stuffed a 598 version in an 08 Stang. Check out the website.

Hey Scott, are them pics from a car from the Reno NV area. I knew of one there in the mid 90-s, looks like the car...I think it sold for like 225k????

Clearly very cool cars that anyone would be proud to own.

Mid 12's for what most Ford guys consider a super car is not impressive.
I read a statement that I'll never forget in one of the hi performance car magizines back in the late 70's or early 80's.
The writer wrote. When it comes down to muscle cars Ford never really did get it together.
I agree.
I had an original 70 440 cuda in the early 80's. The car was a daily driver and still ran high 11's.
Did you ever see how small the ports are on stock 906 heads.
My friend had a 427 Chevelle with square port heads. The ports were so large it looked like you could put your fist in them. I could never understand why his car was slower than my cuda. Now I know a little bit more about head flow and I understand why.
In my town Mopars would always suprise in street races. Many Chevy's would disappoint but Ford wasn't even in the game.

those P-51 heads are no slouch either.
http://www.popularhotrodding.com/tech/0906phr_big_block_ford_engine/index.html

Good looking road runner.

"Of coarse, I talk to guys like this, and hear them talk about track numbers, this will run that, and that would never run this...
They personally have never took anything down the track, ever."
Reminds me of a young guy pitted by us one time, first time at the track with his 70 Olds Cutluss 455, He said "I don't understand it, My car runs 11's on the street by here it only runs 14 flat?" I said, How do you know it runs 11's on the street? "Cause I beat guys whose cars run 12's! all the time!" LOL

Boy this beings back things from the past. I Had a buddy that just had to have a boss 429 in the late 70's at the drop of a hat we off looking at cars not just Mustangs but anything hemi cars 6 pack cars any thing HP . Boy we looked at a few of then around the NW. And Boss 429's not many of them where in one piece. most of them had other motors in them. And the ones that still had the motors with them. Most of them had spun rod bearing what a POS looking rod Ford put in the Boss 429's. yes we found fair number of hemi cars with the same troubles. One of the fixes that some of the old time machinists told me about was that they off set ground the crank and used Hemi rods in them. I was told that with added C I and a cam and headers that the boss 429's ran real good not the 14 & 15 second cars I saw at the time. I went to woodburn onetime in mid 80s to race my 69 Hemi Super Bee and a guy showed up with a B9 car and said that it ran real hard and thinking it would run in the 12's he made 2 passes in the low 15 and left. Greg last time we talked a few years ago you had just gotten your 66 hemi car together how does it run. Ken