Jon Kaase SR71 Cylinder Heads

Pages 4-6 show you how much better they are than the P-51. Quite a bit. Kaase has told me they are very close to the Boss9. That’s why I bought a set instead of the Boss 9s. Kept my headers, intake, valve covers, etc… They are an amazing head for what they are. Kaase told me they are a real “over achiever”. I agree.

738drvr wrote:Pages 4-6 show you how much better they are than the P-51. Quite a bit. Kaase has told me they are very close to the Boss9. That’s why I bought a set instead of the Boss 9s. Kept my headers, intake, valve covers, etc… They are an amazing head for what they are. Kaase told me they are a real “over achiever”. I agree.

Thanks for the information!!

68formalGT wrote:

Lem Evans wrote:

rmcomprandy wrote:What most people don't realize is that the "out of the box" A460 platform is over 30 years old.

Many places have improved and still can further improve this head in many different ways so, the simple A460 power comparison is just not viable to make.

Sure enough. The A460 heads have not had the evolution of the SCJ/P51/SR71 program.

Maybe not yet but if and when the new A460 head is finished from Eliminator it might be a game changer for the A head limited rules platform.

Feb 2019 ..

Where is that updated A460 head ? it's been 4 MORE years ...... We could use it.


After reading this old thread, the SR-71 just might be the updated replacement for us "A" head guys.

Yes I know this is an old thread ,  
But

jonkaase wrote:OK,so I'm not a big airflow guy but here goes...

the intakes we have checked have been 430 to 465 at 28" on a 1020 Superflow bench. That is on a 4.6" bore flow fixture. The real good thing is they are about 400 cfm at .500" lift.

Exhausts are 305 with a 8" flow pipe. The exhaust is exactly the same on the outside of the head as the P-51. The difference is the window at the short turn is .250-.300 taller,  the bowl being deeper.

Does anyone know,  ^  are these out of the box flow numbers  ?  

They kick my new A-460 heads in the nuts out of the box. ....   The out of the box flow numbers for both new sets (two sets) I got since January have been garbage. Nowhere near the Claimed flow numbers.

Got me second guessing my choice ........  


The new heads are finally waking up. Flow is up and the airspeed is approaching 310 fps with a 2.375" valve, which is a hell of an improvement over my 35 year old Ford Motorsport A-460's at around 270 fps at 445 cfm with a 2.4" valve.

Work in progress.  We have more to go.

G-Code wrote:

68formalGT wrote:

Lem Evans wrote:

rmcomprandy wrote:What most people don't realize is that the "out of the box" A460 platform is over 30 years old.

Many places have improved and still can further improve this head in many different ways so, the simple A460 power comparison is just not viable to make.

Sure enough. The A460 heads have not had the evolution of the SCJ/P51/SR71 program.

Maybe not yet but if and when the new A460 head is finished from Eliminator it might be a game changer for the A head limited rules platform.

Feb 2019 ..

Where is that updated A460 head ?  it's been 4 MORE years ......   We could use it.


After reading this old thread, the SR-71 just might be the updated replacement for us "A" head guys.

Good question, I've heard that some have been delivered but as cast and needed to be machined.

G-Code wrote:Yes I know this is an old thread ,  
But

jonkaase wrote:OK,so I'm not a big airflow guy but here goes...

the intakes we have checked have been 430 to 465 at 28" on a 1020 Superflow bench. That is on a 4.6" bore flow fixture. The real good thing is they are about 400 cfm at .500" lift.

Exhausts are 305 with a 8" flow pipe. The exhaust is exactly the same on the outside of the head as the P-51. The difference is the window at the short turn is .250-.300 taller,  the bowl being deeper.

Does anyone know,  ^  are these out of the box flow numbers  ?  

They kick my new A-460 heads in the nuts out of the box. ....   The out of the box flow numbers for both new sets (two sets) I got since January  have been garbage. Nowhere near the Claimed flow numbers.

Got me second guessing my choice ........  


The new heads are finally waking up. Flow is up and the airspeed is approaching 310 fps with a 2.375" valve, which is a hell of an improvement over my 35 year old Ford Motorsport A-460's at around 270 fps at 445 cfm with a 2.4" valve.

Work in progress.  We have more to go.

470+ cfm touted on these ported SR71's.

https://www.facebook.com/photo/?fbid=3707384125945656&set=a.180287858655318

Charlie's Info.

https://www.429-460.com/t27343-kaase-sr-71-cylinder-heads

New 533 SR71 Street Build.

https://www.motortrend.com/how-to/533-ford-big-block-westech-dyno/

Like a lot have said on this message board there's a head for every purpose and if the SR-71'S could complete against what the brand X guys call a conventional head then Ford racers would have completely moved away from the A460's, but they haven't. The SR-71'S are a great head and where you have rules that make you have the ability to run a factory pattern, style, width intake then they are definitely the head to go with.

supervel45 wrote:New 533 SR71 Street Build.

https://www.motortrend.com/how-to/533-ford-big-block-westech-dyno/

1.38 hp per cubic inch? Whoever picked the parts for that thing needs to go back to the drawing board.

Too bad the Thor's went away. I always thought they had a place. Banned too much?

https://www.motortrend.com/how-to/604-inch-ford-big-block-dyno-test-westech/

supervel45 wrote:Too bad the Thor's went away. I always thought they had a place. Banned too much?

https://www.motortrend.com/how-to/604-inch-ford-big-block-dyno-test-westech/

Get the C&C Pro 18 head, pretty much the same thing

G-Code wrote:

supervel45 wrote:New 533 SR71 Street Build.

https://www.motortrend.com/how-to/533-ford-big-block-westech-dyno/

1.38 hp per cubic inch?    Whoever picked the parts for that thing needs to go back to the drawing board.

That's what I kinda thought at first. 9.7/1 compression and a 255 at .050" intake, hydraulic cam and not much lift, it maybe in it's realm.

I think it's more of a pump gas cruiser, weekend warrior deal.

And 2.5" valves are hard to argue with.

https://www.mbellc.com/a460-bb-ford

https://www.facebook.com/100064868490772/videos/799757940622941/
^2021 Video

Availability and Economics is all. That's were the SR71's shine to most now, I believe.

68formalGT wrote:

supervel45 wrote:Too bad the Thor's went away. I always thought they had a place. Banned too much?

https://www.motortrend.com/how-to/604-inch-ford-big-block-dyno-test-westech/

Get the C&C Pro 18 head, pretty much the same thing

Give me a minute as I go outback and shake $10k off the money tree.   lol

Those heads are awesome, but i wonder where the lower end of their application lands  IE: Cubic inches and RPM band.

supervel45 wrote:

G-Code wrote:

supervel45 wrote:New 533 SR71 Street Build.

https://www.motortrend.com/how-to/533-ford-big-block-westech-dyno/

1.38 hp per cubic inch?    Whoever picked the parts for that thing needs to go back to the drawing board.

That's what I kinda thought at first. 9.7/1 compression and a 255 at .050" intake, hydraulic cam and not much lift, it maybe in it's realm.

I think it's more of a pump gas cruiser, weekend warrior deal.

it made good trq ,but the HP not so much. That's a lot of head for that lower RPM engine, even at it's size.

68formalGT wrote:

Good question, I've heard that some have been delivered but as cast and needed to be machined.

Would like to know the changes made

Did you see Glen's SR71 552, G-Code?

It's one of the best stock 2 bolt block, standard parts build's I have seen around here and a single carburetor to boot. Very economical for the HP also, is what I was getting at.

https://www.429-460.com/t28926-dyno-tomorrow

Charlies 1137HP SR71 Deal is in here also.

https://www.429-460.com/t28929-dyno-overlay

The A460 heads have the cast tunnel ram going for them, like I have said before.

G-Code wrote:

68formalGT wrote:

Good question, I've heard that some have been delivered but as cast and needed to be machined.

Would like to know the changes made

Valve angles closer to 351 Clevlands and more rotation of the valve to help unshroud the valves. Eliminator had some on display at PRI a few years ago with a fact sheet.

68formalGT wrote:

G-Code wrote:

68formalGT wrote:

Good question, I've heard that some have been delivered but as cast and needed to be machined.

Would like to know the changes made

Valve angles closer to 351 Clevlands and more rotation of the valve to help unshroud the valves. Eliminator had some on display at PRI a few years ago with a fact sheet.

That could make for some serious gains. That would really piss me off if they come out in the next few months .....  lol

I wish I could read the Info sheet.

Get on it guys ....

Just buy them for the hell of it, if he still has them.

https://www.racingjunk.com/heads/184429609/blue-thunder-thor-heads.html

G-Code, is that any better?

rmcomprandy wrote:

G-Code wrote:

68formalGT wrote:

Lem Evans wrote:

rmcomprandy wrote:What most people don't realize is that the "out of the box" A460 platform is over 30 years old.

Many places have improved and still can further improve this head in many different ways so, the simple A460 power comparison is just not viable to make.

Sure enough. The A460 heads have not had the evolution of the SCJ/P51/SR71 program.

Maybe not yet but if and when the new A460 head is finished from Eliminator it might be a game changer for the A head limited rules platform.

Feb 2019 ..

Where is that updated A460 head ?  it's been 4 MORE years ......   We could use it.


After reading this old thread, the SR-71 just might be the updated replacement for us "A" head guys.

Is IDT still selling heads ... after them and Eliminator split...?

Not that I've seen

68formalGT wrote:G-Code, is that any better?

Much better.  

Thanks

It says nothing about raising the port, or altering the floor on either of them to make for a better short turn.   Rats
That would be helpful. Changing that push rod pinch is certainly a winner and that would eliminate the turn before the short turn, so the floor would be more balanced.

New A460 head progress.
Last night on the flow bench we saw 450 cfm with a 2.320" valve through a 3.47" CSA  =  311 fps.  0n a 4.50" bore.

Got the flow to mellow out through it's rough section  @ .750" - 800" lift where it wants to get unstable.

We hope to maintain the smoothness and flow percentages  with a 2.380 valve. ... Work in progress