Boss 429 passenger, nascar heads?????

[3906pack 10]

Does anyone know the diff between Boss 429- passenger heads, and the nascar versions. I know the intake ports are diff. in size and apparently nascar are better for street driving so I am told. But are the valve covers, valve train, etc all different from the other? Does the O ring in the head pose a problem today on the pass. :whistling: I am going to start piecing a Boss engine together with a real nice boss block that I bought and would like to know these things before I get into trouble. This is not a real boss car project so period correctness doesnt realy matter. I want to build a nice street engine for later. Thankyou and hope I didnt ask any stupid questions.... Danny

[sixty9cobra 10]

Boss heads are huge. The spark plug is in the valve cover they are quite differnet. The othe 429 heads (385 series as they call them) look more conventional like clevaland heads. look at this

http://www.theoldone.com/boss429head/Latest_BOSS_head.jpg

 

 

Im not so sure the block is the same as a 385 series. Dont mix up a 429 cobra jet and a boss they differ in price by a few extra ZEROS IN THE PRICE.

 

http://cgi.ebay.com/ebaymotors/NOS-BOSS-429-NASCAR-Mustang-C9AE-B-head-pair_W0QQcmdZViewItemQQcategoryZ33621QQihZ012QQitemZ220216198489QQrdZ1QQsspagenameZWDVW

 

http://cgi.ebay.com/ebaymotors/1969-Boss-429-Mustang-Refurbished-Heads_W0QQcmdZViewItemQQcategoryZ33617QQihZ007QQitemZ170203691204QQrdZ1QQsspagenameZWDVW

http://cgi.ebay.com/ebaymotors/NOS-BOSS-429-NASCAR-494-CAN-AM-Holman-Moody-alum-block_W0QQcmdZViewItemQQcategoryZ107063QQihZ012QQitemZ220216506793QQrdZ1QQsspagenameZWDVW

[3906pack 10]

I may have not made it clear enough but I meant the difference between Boss 429 passenger car- 1969 70 street heads, and the Boss 429 Nascar racing- Holman Moody. Sorry for the confusion.....Nice engine by the way

[69boss429 106]

Does anyone know the diff between Boss 429- passenger heads, and the nascar versions. I know the intake ports are diff. in size and apparently nascar are better for street driving so I am told. But are the valve covers, valve train, etc all different from the other? Does the O ring in the head pose a problem today on the pass. :whistling: I am going to start piecing a Boss engine together with a real nice boss block that I bought and would like to know these things before I get into trouble. This is not a real boss car project so period correctness doesnt realy matter. I want to build a nice street engine for later. Thankyou and hope I didnt ask any stupid questions.... Danny

 

Your timing is great,if you can wait a couple of months Jon Kasse is working on new Boss 429 heads that will fit most any 385 series block and use head gaskets instead of O rings.

These new heads can use stock manifolds and valve covers and he has dynoed a 429 cu in engine with 10.5 comp on pump gas at 778 HP.

What are you putting this engine in?

The stock heads and Nascar heads will fit on any Boss 429 block and the rockers will fit either,but the Nascar rockers are a different ratio and the valves are larger.

I wish Jon had brought out these new heads before I rebuilt my 1969 Boss,I would have put the original stuff on the shelf,stock O rings alone cost about 1200.00

[3906pack 10]

The Kasse heads will use boss 429 covers? This sounds great whats happening. Amazing power out of low comp. Your car is absolutely gorgeous. Thankyou. Where did you get this info from?

[FallujahMedic 10]

OOOOHHHHH!!! Does this mean that I'll be able to have Boss 429 Nascar Heads (or a reasonable copy) for my dream 588 cu in from Flatlander Racing?? Imagine the numbers.....oooohhh!:biggrin: So much torque to light up the tires in all the gears of that 6-speed:tongue:

[69boss429 106]

The Kasse heads will use boss 429 covers? This sounds great whats happening. Amazing power out of low comp. Your car is absolutely gorgeous. Thankyou. Where did you get this info from?

 

The Kasse heads are Boss 429 heads that Jon redesigned but will take stock Boss 429 valve covers(or Blue Thunder repros),and he will be making intake and valvetrain as well.

Look for Jon to run one at this years Motor Master Competition.

 

And,when Jon ran them on a 521 he was able to pull 902 HP with 10.5 comp and pump gas.Torque was over 700 ft lbs,a tire melter for sure.

[Mach1NH 10]

Any idea when these will be available?

 

Quite honestly, this is something Ford should have offered years ago.

 

John

[3906pack 10]

Has anybody heard of the Tod Miller heads out of Iowa, boss 429?

[sixty9cobra 10]

look here

http://www.dscmotorsport.com/asp/products/content_cylinder.asp?SubCat=9&GroupID=2

[3906pack 10]

wicked looking engine you have there, do the rear wheels hook up on that buggy? hahahahaha Thanks for the links. Last weekend at the Ford swap meet in Ohio, I bought a 1969 429 boss block in very nice shape, with nascar caps, standard bore. I guess im heading in the direction to change my 69 stang into a boss 9 powered car. My fasback is originally a smallblock, with a bigblock now. But what the hell. Ive heard that the shock towers are available. $3000.00 Any body heard of experimental engines in Brighton, Michigan?

[69boss429 106]

Boss 429 stock shock towers

[69boss429 106]

wicked looking engine you have there, do the rear wheels hook up on that buggy? hahahahaha Thanks for the links. Last weekend at the Ford swap meet in Ohio, I bought a 1969 429 boss block in very nice shape, with nascar caps, standard bore. I guess im heading in the direction to change my 69 stang into a boss 9 powered car. My fasback is originally a smallblock, with a bigblock now. But what the hell. Ive heard that the shock towers are available. $3000.00 Any body heard of experimental engines in Brighton, Michigan?

 

Why even have shock towers,if it's not an original Boss 429 cut the towers out and give yourself some room for the headers.

Even with the unique towers on a stock Boss 429 they are a PIA to work in.

[3906pack 10]

Wicked looking tarmac shredder you have. Appreciate all the good info. Seems you been around the block a few times with boss stuff. Have you heard of the new boss magnesium repo covers being made soon?

[3906pack 10]

Just recieved my boss 9 engine stroked to 514 keeping the standard bore with the Tod Miller heads built by Shotgun Hemi Parts in Detroit by Eric Simone. Runs on pump gas 10.5:1 made 594 bhp @ 6000 rpm. with 640 lbs of torque. Decided to go with hydrolic roller bumpstick, so im limited to 6000 rpm. Thats ok with me for the street...The T.Miller heads are in the engine masters competition and are currently ahead in the points. Kasse still has to run his engine yet. Thank god all these goodies are still made in the USA.....

[stangme428 33]

WOW thats sweet!!! cant wait to see more build pics and the finished product!!:punk:

 

Just recieved my boss 9 engine stroked to 514 keeping the standard bore with the Tod Miller heads built by Shotgun Hemi Parts in Detroit by Eric Simone. Runs on pump gas 10.5:1 made 594 bhp @ 6000 rpm. with 640 lbs of torque. Decided to go with hydrolic roller bumpstick, so im limited to 6000 rpm. Thats ok with me for the street...The T.Miller heads are in the engine masters competition and are currently ahead in the points. Kasse still has to run his engine yet. Thank god all these goodies are still made in the USA.....