As many of you know, ZZPerformance has been pushing to find the limits of the LNF. I installed a prototype ZZP turbo upgrade last spring, but quickly maxed the fuel system. As others had found, 400whp is pretty much the limit. I decided to go back to the stock turbo until we had a fix for the fuel system. We ported the cylinder head, which significantly increased HP at the same boost level. Unfortunately, the max boost we could push from the stock turbo decreased so much that we saw very little HP gain overall. Next, we set a goal to hit 11s on the stock turbo. Within a couple months, I hit an 11.99 at US131 Motorsports Park in Martin, MI. We met our goal, but the stock turbo was maxed. This setup put down 338whp. One day while taking voltage readings from the fuel pressure sensor, an idea popped into my head. I decided to alter the signal being sent to the ECM to trick the ECM into raising the fuel pressure. We put together a simple device to decrease the voltage and the car ran very rich. We decided to make a dyno pull. The result was promising- the WOT air fuel had dropped from mid 12s all the way to high 9s. We backed off the voltage drop a bit and then tuned in the fueling. This mod gave us less than 10whp on the stock turbo, with a peak of 345whp(sae), but we knew it would be much more valuable on turbo swap cars.

The next step was to install the latest prototype ZZP turbo swap. This kit included a Bullseye/Borg Warner S256 extended tip turbo. With the fuel pressure mod in place and now able to take advantage of the ported cylinder head, we quickly surpassed 500whp. On 110 octane, and fuel pressure increased to more than 3400psi, I made a best pull of 530whp sae at 27psi. At 23 psi, this setup was good for 11.40s at nearly 127mph in the 1/4. However, I felt that a smaller turbo may be better suited for daily drivers while still offering 450whp potential. We decided to test out the S252 extended tip turbo and set it up with a smaller exhaust wheel for quick response. We also decided that it would be best to re-install the stock cylinder head to more accurately set up a mail order tune for our turbo swap kit. While the motor was apart, we took the next step to thoroughly examine the internals.

This is what we found-

All four connecting rods were bent. Ouch. We are currently working with two top name connecting rod manufacturers on a cost effective solution. We are also planning to sell forged pistons, likely from JE. While my motor is apart waiting on upgraded rods and pistons, we installed the stock shortblock from one of our parts cars as well as the original stock cylinder head.

Next, I contacted Vince from Trifecta about teaming up on our ECM file for our turbo swap kits. He agreed and set up a base file for us with adjustments made to the fuel pressure tables. We currently have the max fuel pressure set at 2800psi. On paper, this showed potential for approximately 60whp gains over stock fuel pressure. This would allow us to reach our goal of 450whp on the S252et turbo.

Initial dyno testing has been successful. I started out with 110 octane for a safety margin while experimenting. After a few pulls, I was able to put down 457whp at 23psi. This pull pushed the limits of the fuel system once again. After the tune was complete, I drained the gas and switched over to 93 octane. Unfortunately, it is undesireable winter blend 93. After a handful of pulls, the best run was 425whp at 22psi. I believe we should be able to achieve 435-440whp once we get the cam tables dialed in and add a little more boost. These are uncorrected dyno numbers. While we normally post corrected numbers, actual HP numbers are more relevant when discussing fuel system limitations.

Here are the dyno charts-


I still have to work on the ECM boost control. A slight boost fade will allow more power through the midrange without maxing out the fuel system in the higher RPMs. While testing multiple boost levels at multiple RPMs, I pushed boost into the mid 30s at 3700 RPM. This resulted in a torque reading of over 500 ft lbs! Furthermore, at 29psi, this setup surpassed 400whp at less then 5000 RPM.

Thanks for reading this long post. I will have more updates and pics soon…

 

wow, so basically an S252 and Tuning would put me around 415hp??

 

nice

 

someones up late hahaha. cant wait to see everything come out!

 

way to go ZZP!!!!!

 

So I have to ask, what is it gonna cost, preliminary prices of course, and when is it going to be up for purchase?

And one other thing... have you guys thought about an e85 tune, here in boise a lot of the higher hp cars such as evo's and supra's and things are all on e85 and if I were to invest in such a kit, I would love to have the option to be a part of the e85 army here in boise.

 

Thank you ZZP for pushing our cars further! Love to see a vendor really trying to see what our cars can do. I'll definitely be watching for your internals to become available!

 

you know what can be learned here, instead of bickering back and forth about which vendors are better, etc... THIS is the way **** gets done... great job on both ZZP and Trifectas part on this

 

pretty bad ass man.
I have to say, you guys do some sick work there. that's pretty nuts on the rods, but a bent rod is better than one hanging out the side of the block,
hit up Pauter, they make some pretty bad ass rods for a semi decent price. Just send em a stocker to get measurements from and I'm sure they will get em made for you no problem. best is those things are good to over 350hp per cylinder (0verkill of course, but better than nothing). billet 4340 ftw

 

Damn boys. That is sick. Keep us updated and keep pushing that thing.

 

Nice information and while perhaps not up to that type of abuse, it is a testament to the stock rods that they didn't suffer a catastrophic failure. Are you still altering the signal from the pressure sensor on the rail or only with calibration adjustments in the tune?

 

wow didn't think the cintered steel rods would bend, figured they would break.

 

So the rods bent at 500hp+ they should be fine for guys only wanting 425hp. great work ZZP looking forward to that intercooler your working on and this turbo kit of course.

 

Dang I want an lnf so freaking bad I can taste it! Nice wok guys! You have really made a name for yourselves, at least in the cobalt scene, in the past 2 years.

 

I wonder if the rods bent on the run you did that went to the a/f of 9.....causing mild hydro lock. Isnt there a theory that some of the other pistons had popped from being too rich, and they weren't close to a 9 a/f ratio.

 

that's some good stuff. is that the stock rod? correct me if I'm wrong.

 

great work guys keep up the progress

 

9's afr won't hydro lock a motor. lnf is direct injection and they don't like rich afr's.

 

damn subd

 

nice work

 

500 ft lbs in the mid range!

So how was it running with the bent rods? Did you notice knocking or strange noises?

This is amazing work overall. I wish you guys supported the kappa platform, but i think i'll trade my cav for an LNF cobalt soon enough

 

Billet would be sweet, but maybe not so great for cost reasons.. Maybe a good forged H-beam would be a good less expensive solution?

 

eh they will still cost around the same in the beginning. custom rods aren't the cheapest thing. I had em in my motor when it blew and they came out still looking brand new lol.
I paid $865 shipped for a set of custom rods from pauter, not going to get too much cheaper with a forged rod maybe in the $550-$650 range setup since it's not really going to be a big seller in the aftermarket world

 

Nice work guys!

 

Well, I guess hydrolock wasnt the correct wording, but I wonder if the bent rods are connected to the rich afr.