Re: Jon Kaase SR71 Cylinder Heads

jonkaase November 5th 2018, 6:35 pm

Jon Kaase SR71 Cylinder Heads - Page 5 C12

This is with the Tunnel ram in Feb. Different set of heads with big Book billet carbs(2) It doesn't show it but the vacuum pump was running, probably about 18" Hg. Heads were the same SR-71's except I ground the guide bosses down somewhat. It was a MAX effort. Notice the power holds on even at 7900.

Carl November 5th 2018, 7:35 pm

jonkaase wrote:In the one picture you can see the Fel-Pro 1231 gaskets on the intake surface. I lost the gaskets that came with the manifold! But you can see why the SCj intakes would have a huge mismatch.

The AFR head intake ports are on standard port centers, which makes it easy to match intakes like the Torker II, Performer, Stealth, etc. to them.

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cobrakid8 November 5th 2018, 7:54 pm

That’s so awesome Mr. Kaase! Good to see some back to back testing on your own heads like that.

A few questions since I am sure it will be asked later. Any other changes to the motors besides just the heads being changed out? Like cam or anything else?

Also if you need any of these to be a test mule I am not a far drive away in the Nooga lol!

Congrats on some badass heads!

nitrous.f November 5th 2018, 10:49 pm

yea thanks mr kasse! now that you developed these heads and made over 1100hp with them, iam now looking at my a460 heads and saying what the Shocked

great build and keep um coming!
are these better than the a460 heads? let me know!

Mark Miller November 6th 2018, 12:28 am

jonkaase wrote:Lets start with the 521"
This engine came to us from Ford Motorsport in 1999 in the form of a CJ crate engine. We used it when testing the original SCJ heads that we sold to Ford. Then the P-51 testing followed by all the Boss 9 testing. It is the Finger in the Port engine that had all the videos done for my AETC presentation, as well as anything we have ever needed to run and punish. Then came all the SR-71 tests. It was a re-manufactured block when Ford supplied it. I would like to know the history of this block before Ford got it!
It is a 70 block with main studs and 8 lifter bushings. no fill. The bore is 4.390, (+.030")
Callies 4.3 crank, Lunati 6.8 rods, The cam is Comp 273-280, 109CL .460" lobe, 1.73 Comp rockers.
Pistons are Diamond shelf flat top with 1/16, 1/16, 3/16 rings. No gas ports. .020" deck clearance. It's all pretty tame stuff
Compression is 12.4

I was going to ask about the 521 with the P-51 so it's the short block that probably has over a 1,000 dyno pulls on it? Smile

Thanks for all the dyno charts can't beat the P-51 and SR-71 heads IMO!! :)Also what's the compression ratio on the 521 with the P-51 Heads,Thanks Smile

boss9coupe November 6th 2018, 10:16 am

Can't wait for round 2 of the SR-71 testing.. Awesome results i suspect..

Just to put some perspective on Jon's work on the Raised Intake port..

Jon Kaase SR71 Cylinder Heads - Page 5 45427210

Jon Kaase SR71 Cylinder Heads - Page 5 45442010

Jon Kaase SR71 Cylinder Heads - Page 5 45508310

windsor November 6th 2018, 10:19 am

I was going to ask about the 521 with the P-51 so it's the short block that probably has over a 1,000 dyno pulls on it? Thanks for all the dyno charts can't beat the P-51 and SR-71 heads IMO!! :)Also what's the compression ratio on the 521 with the P-51 Heads,Thanks

jonkaase wrote:Lets start with the 521"...Compression is 12.4

fordsrgrt November 6th 2018, 11:01 am

Jon, got a set of the SR-71 ordered, was wondering your thoughts on this cam 288/308 @.050 on a 114 and .480 lobe, thanks

jonkaase November 6th 2018, 1:10 pm

That is perfect if it is big enough and has compression

jonkaase November 6th 2018, 1:12 pm

Boss9coupe, those heads have some travel miles already!

glenevans November 6th 2018, 1:26 pm

Those heads look awesome! Thanks for the great product line (I have some P-51 heads, aluminum oil pump and rear main seal). Heads are ported and 2.30 valves

boss9coupe November 6th 2018, 2:19 pm

jonkaase wrote:Boss9coupe, those heads have some travel miles already!

Yes Jon, Thanks to you and your team..came through in better than new condition..the only problem i'm having is Big Bad Boss Hemi.. is real pissed off about some new kid on the block.. invading on his Turf Evil or Very Mad

glenevans November 6th 2018, 4:39 pm

What size pushrod have you been using on the SR-71 heads? Are they drilled for 7/16" p-rods? Thanks

ED468 November 6th 2018, 9:46 pm

Really nice to see the FORD guy have a better conventional head to compete with them Chevy Boys so called conventional heads Cool

Mark Miller November 6th 2018, 11:58 pm

windsor wrote:
I was going to ask about the 521 with the P-51 so it's the short block that probably has over a 1,000 dyno pulls on it? Thanks for all the dyno charts can't beat the P-51 and SR-71 heads IMO!! :)Also what's the compression ratio on the 521 with the P-51 Heads,Thanks

jonkaase wrote:Lets start with the 521"...Compression is 12.4

He said the 521 Short Block with the SR-71 Heads was a different short block than the 521 P-51 Short Block but I guess they both could be 12.4:1 Compression,Thanks:)

Mark Miller November 7th 2018, 12:00 am

boss9coupe wrote:Can't wait for round 2 of the SR-71 testing.. Awesome results i suspect..

Just to put some perspective on Jon's work on the Raised Intake port..

Thanks for those pictures it shows the big difference between the SR-71 Head and the factory cast iron castings!! Smile

boss9coupe November 7th 2018, 8:01 am

Thanks for those pictures it shows the big difference between the SR-71 Head and the factory cast iron castings!! Smile

[/quote]

Your welcome a CJ, SCJ, P51 etc..would of been a better comparison i just didn't have any lying around..as you know same low port location just bigger port opening..

BigBlockRanger November 7th 2018, 12:04 pm

Fantastic info. It's so great that Jon will come here and share his work with us regular guys.

The streetcar inside me wishes these types of tests were sometimes done with compression ratios more suited for use with pump super unleaded.

HorsinAround November 7th 2018, 4:30 pm

I just wish these would have been ready when I was ready to buy heads. Looks like I'm stuck with the crappy old AFR 315's. Very Happy

Dave De November 7th 2018, 6:34 pm

I am fortunate to have bought a pair of these a few weeks ago before they will be sold out and the waiting line begins.
I will be able to compare them on the track against my old P-51's and SCJ's where I have track data on my 580 cube motor. Both were altered but the SR-71's will be as received out of the box. They should be set up in a few weeks but the tracks are closed until spring. I may haul the car south to satisfy my curiosity.

BBFTorino November 7th 2018, 11:56 pm

Dave De wrote:I am fortunate to have bought a pair of these a few weeks ago before they will be sold out and the waiting line begins.
I will be able to compare them on the track against my old P-51's and SCJ's where I have track data on my 580 cube motor. Both were altered but the SR-71's will be as received out of the box. They should be set up in a few weeks but the tracks are closed until spring. I may haul the car south to satisfy my curiosity.

The streets of Oklahoma are always open!! Very Happy

Dave De November 8th 2018, 12:34 am

BBFTorino wrote:
Dave De wrote:I am fortunate to have bought a pair of these a few weeks ago before they will be sold out and the waiting line begins.
I will be able to compare them on the track against my old P-51's and SCJ's where I have track data on my 580 cube motor. Both were altered but the SR-71's will be as received out of the box. They should be set up in a few weeks but the tracks are closed until spring. I may haul the car south to satisfy my curiosity.
The streets of Oklahoma are always open!!

No data for that option.

Dave De November 8th 2018, 12:58 am

The stud bosses on these heads seem to be higher than the P-51's. This makes the rocker trunnion closer to the base of the stud where its going to be stronger from side loading. Push rod lengths are much longer at 9.400 and 9.450.

Piston valve relief clearance
My Diamond piston reliefs were cut for modified P-51's with 2.300" diameter intake valves. The valves on the SR-71's are 2.375" where I expected interference. I checked the clearance to find that it has .160" radial clearance in the relief. This tells me that the valve centerline is closer to the piston center than the P-51 head. Those of you that have pistons with reliefs for SCJ/P-51's with 2.25" valves should have less clearance to something around .130" which is acceptable clearance where you wont have to cut the pistons. But you need to check it to make sure.

jonkaase November 8th 2018, 8:38 pm

Jon Kaase SR71 Cylinder Heads - Page 5 Ddd10

The 598 getting ready for dyno test. The heads were cut .045 for a little over 16:1 compression. New cam in, 287-312, 115CL. .483 lobe with Comp 1830 stud rockers. The lobes are super smooth to run rpm with the steel valves. I changed to the belt drive so I could move the cam around easily.( after picture was taken)

jonkaase November 8th 2018, 8:41 pm

Jon Kaase SR71 Cylinder Heads - Page 5 Ccc10

One hour ago.

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