How's it going? Its been a while.

So I've got this dude. He has a K24 that has the following.

13.1:1 Compression on an 87x99 shelf setup
RBB head 4 Piston Pro TSX'd
DTR Header
4 Piston K600 Single Lobes on Ferrea Rollers(Cam gears degree'd by 4P)
Skunk2 Ultra Intake Manifold w/ 90mm TB
Ignite Red E85

I made my way a few hours from home to a dyno location in Central Indiana to tune it. The results were ok. We did what we can but it didn't reach his goal of 300whp. Shortly after driving it he came to realize that the single lobe setup wasn't for him. He originally didnt plan on street driving the car much but things changed and now his target was to gain some midrange back while trying to eclipse his 300whp goal.




Here is what it made with the existing combo. It was tuned on a newer style DynoJet in about 45-50 degree weather. We were unable to get a run vs. RPM, well we can. I just have to ask for it.

The power was decent and the car was fast, just lazy down low. As to be expected by a small displacement setup on single lobes with no VTC.


Fast forward a couple months. He scored a set of Pro Jay 62mm ITB's. It was a gamble if they'd work or not for this combo. So we tested them out.


Included is the same run vs. speed. My RPM pickup is starting to take a **** on me so ignore the RPM spikes please.



This is what it looked like under the valve cover.





Also as far as variables outside of the ITB change. It's a different dyno (still a dynojet set on STD) but it was 28 degrees outside and my dyno room was 53 degrees, we were forced to go onto pump e85 vs. the ignite red it used to be on, and obviously months apart from when we tuned with the ultra. I still count it as a gain though.



Next up is to see if VTC does anything vs. the locked intake cam gear. The cams were degreed by the handsome guys at 4Piston. We threw in a PND gear and tried to use a VTC limiter pin. That **** didnt work. I Removed the pin and went back to work. I kept the VTC limited to 35 degrees since we didn't have the ability to clay for V2P. The change from 30-35 in the mid was minimal anyhow.


Again, included is a run vs. speed because of my wonky *** RPM pickup.




Ultra 2's installed and ready to go. The exhaust gear is degree'd per manufacturer specs.

VTC did what we all assumed it would. It woke up the midrange a little and we were able to squeeze a hair more up top. Next was to try a 3 lobe camshaft. Its pretty obvious that even a stock camshaft would rock out over a single lobe on the low end. We chose a set of Skunk2 Ultra2's. It seemed like a good fit for the combo for our initial 3 lobe testing.


The peak torque is highlighted on these runs. The tuning had to stop at about 90% completion due to a broken starter. I was finishing the touch ups on the midrange with VTC and fuel. I don't feel like there was a whole lot left on the table, just a little bit of smoother phasing. It made over 200 ft lb's by around 4600 RPM's, so that was pretty sweet, but it didnt peak out on torque as good as the K600's.





The overlay shows the K600's rocking out from 5200 to 7200 and the Ultra2's taking over after that. The 3 lobe magic did its thing downlow making nearly 50whp and 50 ft lb's down low. The next plan of attack will more than likely be either a Pro156, but more than likely a Pro163. After that we may try another set of cams to see how it does on top of a higher flowing head.



Thanks for reading. Thanks to Tyler for the opportunity.

Check out our FB link in my signature below and follow up on Instagram under MikeySpec to keep up with some of the random testing and data and pictures of my cat.

 

Great testing and write up Mikey! I'd like to say on behalf of the community, as well as myself, thank you for sharing your results with us. Always a treat to see 1st hand results from someone reputable and unbiased. I'm sure this will help some guys pick parts a lil better when building a similar setup. 👍

 

May i ask you if you was running pump 93 gas on that compression what afr would you have aim for?

 

Fasho Fasho

pump e85, measured around e65 currently from this pump.

 

Great stuff as always Mikey. Thank you for sharing!

 

 

awesome test thank you mikey

 

Need me some ultra in my life

 

thanks as always for the testing, bet this thing is a blast to drive.

 

Awesome as always Mikey. This makes me want to build an all motor K24 so bad. 300whp never seemed so easy...

 

Great post, we need a lot more of this here in the forum. It's nice to see people who actually test stuff and try things out, makes for great entertainment and knowledge. Thanks.

 

Power seems a little low for having a ported head, no?

I would expect this set up to make 340-350whp

 

As far as I know, there's not a lot of people who make good power on RBB heads. Ported or not it wont make jam like a PRB. Anything over 325 on a mild 99mm is solid IMO. We'll probably get there pretty easily after a head swap and allowing a hair more compression at the same time.

But yeah, power seemed down. So we tested stuff to try and find it. That's kind of the point of this.

 

4piston's ported tsx head is not their heavy hitter. They recommend it for stock to mild k20s.

 

Yeah, I agree with Mikey and doood, you need a "Pro 163" from 4piston for mid 300's and up.

 

This is a 87x99, stock tsx port, ktuned big tube header, full exhaust and DC 4.5 car on pump e85

 

I thought that setup was a RBC head at 13.7:1? Either way, its beastly. I personally make more power on RBC heads than RBB's and still have yet to see RBB heads make good power. Stock cast for stock cast(RBC vs RBB swapped) on a stock k24a2 bottom end using Cartel 3.2's i saw as much as 12whp up top with no other changes.

Another change we plan for is to put on a stock thickness HG on this setup to bring the compression closer to the 13.5-13.7 ballpark instead of the 12.8-13.0:1 that its at now.

 

Hi, I know it's an old thread, but I have the same combo
k24 / k20
IM ultra centerfed tb 80mm
sk2 ultra 2 cams
currently I have cr 12.5, it is only used at pump gas 93.
my question is to pump gas with ultra 2 cams would be better cr 12.5 or 13 ?? what was your max ignition in wot with cr 13?