Boss 429 Retrofit from Kaase

[John Casey]

Something of interest for you big block guys in today's Hemmings e-Weekly:

Performance

Jon Kaase introduces Boss 429 retrofit kit

Jon Kaase has designed a complete kit to turn a production Ford 429/460 engine into a Boss 429-style hemi.photo courtesy Jon KaaseFord’s Boss 429 hemi was a loaded weapon intended for the NASCAR arena and aimed squarely at its cross-town rival, Chrysler. Unfortunately, Ford only constructed enough consumer versions to satisfy NASCAR, making them exceedingly rare, and as a consequence, highly valued.

Seeing the potential of Ford’s design and recognizing the lasting appeal of the Boss 429’s visual impact, noted race engine builder Jon Kaase has designed all-new components to create what he’s dubbed the Boss Nine Hemi retrofit kit. The kit is intended to fit on a standard Ford 429/460 Lima-style 385-series V-8 without requiring any custom machine work.

The key to the kit is the aluminum cylinder heads, which have revised ports and combustion chambers along with relocated spark plug locations, to enhance airflow and increase combustion efficiency. A new rocker system has also been devised in conjunction with W.W. Engineering to eliminate the potentially troublesome offset design of the original Boss; Manley valves designed for big-block Chevy engines were utilized to maintain parts availability while avoiding the costs of custom pieces. Similarly, the Boss Nine heads are mounted using stock 460 gaskets for the heads and the intake and exhaust ports; it also retains the stock 429/460 oil drain-back holes.

Kaase’s intake manifold is also revised, though it will fit on Ford’s stock Boss 429 heads. Those revisions allowed the new intake to make 50 more horsepower than Ford’s NASCAR single-plane manifold and 100hp over the stock dual-plane manifolds used on production Boss 429 Mustangs. Kaase’s manifold is offered for 4150-style carburetors or for 4500-series Dominator units.

While he was at it, Kaase also designed a new oil-pump housing for the 429/460 to eliminate the factory pump’s tendency to crack. The crowning touch for the Boss Nine Hemi kit is a pair of stock-appearing rocker covers. To see and learn more, go to www.JonKaaseracingengines.com.
- By Terry McGean

[stack]

cool I would love to have that. Can't even imagine what it costs

stack

[gt40tt]

Originally Posted by stack

cool I would love to have that. Can't even imagine what it costs

stack

Suprise,they are not really to bad.
$6000 for complete heads with rocker arms and valve covers
$700 for the manifold
A tad smaller than a DOHC mod engine and good for 7 to 800 hp with no huffer
Great eye candy under any hood

[stack]

That is rally not that bad of a price. Does that include the cams?

stack

[gt40tt]

Originally Posted by stack

That is rally not that bad of a price. Does that include the cams?

stack

This is not an overhead cam engine,it is a Ford Boss 429 hemi engine.
Only 1 cam required in it's usual place ,in the block.
But it is not included,however,Comp has some good grinds for Boss 429's

[2FAST4U]

That is one wicked engine in a Cobra. Whose is that?

[JayP]

gt40

Have you already made the jump? or those just comparison photos?


Now where would I put those - the spyder or the 70 Cougar hmmm....

THANKS for that link.

[gt40tt]

That image of the Boss 429 engine in the Cobra is off the Club Cobra site.
And,no I have not built one except in my dreams.
I did get a ride in an original 427 Cobra back in 1969 about 2 months after I had purchased my Boss 429.The dealer that had it wanted to give me 3500 in trade after I had just paid 5200 for the Boss.
When I finally get around to building one I would love to put a Boss 429 under the hood.
Maybe I should get together with FF5 for a prototype deal !!!!!

[SC210Ford]

I have a stock 460 I can get my hands on. What else would I need to make a Boss 429 besides these heads and a cam?

Would a stock bottom end hold up and is so what kind of numbers would it make?

[2FAST4U]

You would need to change out the pistons, rods, crank, and get an intake manifold. A two-bolt 429/460 block is good for about 700 HP.

[stack]

wasn't there a 429 sohc motor?

stack

[2FAST4U]

No. A 427 SOHC engine that was designed in the early 60's

The 427 "Cammer" was based on the 427 side oiler FE engine and was quite unique.

[SR71]

Stack - are you perhaps thinking about a 427 sohc?

[JayP]

here's a good illustration of 427 SOHC note timing covers...

http://www.supermotors.net/articles/...sue01-a2-1.php

[gt40tt]

Originally Posted by 2FAST4U

You would need to change out the pistons, rods, crank, and get an intake manifold. A two-bolt 429/460 block is good for about 700 HP.

You could actually use the stock crank and rods but pistons would need to be replaced.
And,yes to a new intake from Kasse

[Rob Burton]

I have been following Kaase's progress on these heads for some time. He has a standard bore and stroke block with forged internals. He put these heads on it with his intake and got over 900hp out of it with a single carb.

[SC210Ford]

Originally Posted by gt40tt

You could actually use the stock crank and rods but pistons would need to be replaced.
And,yes to a new intake from Kasse

So If I rebuilt the bottom end with forged pistons and bought these heads and intake, and a cam I'd have a sweet Boss 460, (Sweet probably isn't the word for it)

possible power plant for a '33 roadster

I would have gone with a new cam heads and intake anyway.

[gt40tt]

Originally Posted by SC210Ford

So If I rebuilt the bottom end with forged pistons and bought these heads and intake, and a cam I'd have a sweet Boss 460, (Sweet probably isn't the word for it)

possible power plant for a '33 roadster

I would have gone with a new cam heads and intake anyway.

Ultimate eye candy under any hood.

[SC210Ford]

you guys are going to get me in trouble!

[Sinatra Fan]

That would make a sick motor in the 33

Makes you go hmmmmmmmmmmmm

[Bigblockbandit]

I have an original boss 429 crank and rods sitting in a 429 block with DOOE heads on it right now, the dream has alway been to find a set of Boss heads to put on top of that motor and drop it in my pickup truck...

[KC Wildcat]

gt40tt - not sure about ultimate eye candy, but certainly up there. Not sure anything beats a cammer (427SOHC), but nobody is going to be ashamed of the big boss. I get goose bumps thinking about it.

[fastmerc]

Nice stuff!!!! BUT, if you are not a racer or a dealer......you go hungry!

Sounds like response is good to his new stuff...but he's playing "Boss Nazi" in terms of whom he will sell too........

SO, be prepared to buy from someone that will add a mark up.......

Steve

[JayP]

foolish on his part if true - hot rod market would love those engines

Im dreaming about retrofitting my 70 cougar with that engine and tube front end.

[John Aldrich]

I don't know about seperate parts, but Kaase sells crate motors direct. He said the complete engines start around $25,000.
John

[jjo]

fastmerc- you are incorrect. Kaase will sell any component you need. I just finished my engine and they went the extra mile to provide the components I wanted the way I wanted them. They did all machine work, I did the assembly. For those of you interested in Boss 9 performance, here is an excerpt from a post I made on the other Cobra site a week ago:

Dropped off the Boss 9 at the Kaase shop Friday AM and Jon called late Saturday with the results:

980 hp between 6600 and 7000 rpm
~ 815 torque

All natural, pump gas.

This is a 600 cid Ford 385 series engine with Kaase Boss 9 heads and intake - as cast, no port work, aluminum block, and a single four barrel carb. The cam is not an all out quarter mile cam, but is substantial and not appropriate for a long road trip.

John Owen

[JayP]

OMFG

Those are great numbers...

[fastmerc]

jjo,

How long ago was this that you purchased your parts??

It was about 3 weeks ago that I talked with this guy, but I truthfully don't know exactly when he called Kasse. Could be a relic deal.....before Kasse started receiving good mass quantities.....I'll tell him to try it again!!!!

Thanks!
Steve

[jjo]

Brief update on my Boss 9 progress

Kaase called yesterday evening while driving home - He had been playing with the newest version of my BOSS 600 on the engine dyno. The same basic engine as the 980hp pump gas version described above, but runs on unleaded race gas and has substantial head modifications and porting - still a single FB carb

The results?

1,088HP at about 6800 rpm

I think that will be enough for now - time to get back to the chassis construction so I can drive it someday....