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(Not*) Mediocre 242

Bit of a disappointing time on the dyno for me yesterday. Here's some of dyno plots from yesterday with the Xona (red, blue, green) and one old run on the 7670 EFR (yellow) for comparison.

u3ja2qWl.jpg


The pull on the EFR was at like 65°F ambient, and yesterday with the Xona was like 90°F, so the Xona will be relatively down on power compared to the EFR. Max power on the EFR was 482 whp revving to 7300 RPM. Max power yesterday with issues on the Xona was 486 whp revving to 6300 RPM. The EFR torque comes on hard at ~4200 RPM and starts to taper down. The Xona torque is a little slower to peak, but once it does, is flat to redline.

I made a few pulls at 27 psi trying to burn some fuel to get my ethanol content up above 60%. No problems there, and made 450 whp. When I got the ethanol content up above 60% and boost turned up to 30 psi, I kept having some issue with my lambda sensor spiking lean right above 6000 RPM, which killed the runs, but made 486 whp at 6300RPM. Based on the lower boost pressure pull, I would think with a full pull at 30 psi I could maybe get to 500 whp with the Xona without changing anything. That's pretty disappointing to me since my ECU airflow calculations seem way off predicting ~70 lb/min of airflow. I need to dig into that a little and figure out why it's predicting so much extra airflow. I'm sure the questionable lambda sensor isn't helping, but I wonder if that's the only issue. Maybe my injector calibration data isn't quite right.

You can definitely feel where the Xona wants to be. There's a point where it almost feels like vtec is turning on as a significant power increase happens at higher RPM. That's likely just the compressor getting into the peak efficiency island and dropping the power requirement from the turbine. I really need to increase my engine VE so I can get some more mass flow, and/or up the boost a little bit to really take advantage of it.

npDcGCAl.jpg


I've been thinking about getting a KL racing T5 cam to replace the RSI stage 3 I currently have. I haven't pulled the trigger on it yet because I haven't heard about a ton of results on turbo cars, but I might now. A cam upgrade, 35 psi, and fixing my lambda sensor issue would hopefully get me to 600 whp. I think that will be my new goal.
 
@t8fanning whats been done to the head? 8v volvo engines are absolute dog turds when it comes to VE and it’s all in the head. If it’s an RSI ported head, there’s some gains to be had.
And the RSI cams are not extreme by any stretch of the imagination.
 
That's some good power! Either way I think Kenny did back to back dyno runs and even the ipd cam made more then the rsi stg3 iirc. i would almost be tempted to just get a Schneider regrind to your specs.
 
dl242gt said:
Quite significant power. That is awesome. I would also consider an enem K15 turbo grind for the kind of power you are looking to make.
Click to expand...
It's not bad, but definitely not what I want. I'll have to look into the K15. I'm pretty well set on the T5, but we'll see.

culberro said:
@t8fanning whats been done to the head? 8v volvo engines are absolute dog turds when it comes to VE and it’s all in the head. If it’s an RSI ported head, there’s some gains to be had.
And the RSI cams are not extreme by any stretch of the imagination.
Click to expand...
It's got 48/40mm intake/exhaust valves, RSI valve springs and chromoly retainers, and is ported. It's not an RSI port, and I'm not sure who did it, but it's definitely ported. I could/should probably up the RPM limit a bit too because it's definitely still making power up there. Probably not to 8000 for the sake of my valve springs, but at least 7500.

Yeah, I think I've just gotta get the T5 cam and buckets.

cosbySweater said:
That's some good power! Either way I think Kenny did back to back dyno runs and even the ipd cam made more then the rsi stg3 iirc. i would almost be tempted to just get a Schneider regrind to your specs.
Click to expand...
My issue is I don't have good specs. I don't really know what makes a good camshaft. People seem to like the T5 cam, and it's been recommended by a few people, so that's why I'm leaning that way.
 


I'm not sure if this is a fair comparison with your setup because your shooting for much higher RPM powerband than I am but the results were obvious to us. The RSI cam does make good power but its much higher up in the RPM band. I would guess that if you ran the IPD cam / K15 cam but retarded a few degrees you would see some decent gains.
I don't know your exact goals but considering the transmission that your running I don't think overall powerband is going to be such an issue for you and peak power might be the ultimate goal. Ether way I think this build is awesome and hope to see some videos of this transmission / engine combo soon.

-Sam
 
RoadRacer4Life said:
I'm not sure if this is a fair comparison with your setup because your shooting for much higher RPM powerband than I am but the results were obvious to us. The RSI cam does make good power but its much higher up in the RPM band. I would guess that if you ran the IPD cam / K15 cam but retarded a few degrees you would see some decent gains.
I don't know your exact goals but considering the transmission that your running I don't think overall powerband is going to be such an issue for you and peak power might be the ultimate goal. Ether way I think this build is awesome and hope to see some videos of this transmission / engine combo soon.

-Sam
Click to expand...
That is definitely interesting. I wish I knew more about about camshaft specs and their effect on powerband and torque. If my engine reflects the same torque gains yours did, that would be significant. I do wonder if they would carry over though.

This car is mostly just fun for me to build. I'd like to see 600 whp, because I want to be able to properly test and show off the turbo. But really it's just a fun street car I can surprise people with.

I hope to take some videos soon, but I'm trying to improve the shift quality a little bit before I do, and I got distracted by getting ready for the dyno and some other things I'm trying to make for it.
 
t8fanning said:
It's got 48/40mm intake/exhaust valves, RSI valve springs and chromoly retainers, and is ported. It's not an RSI port, and I'm not sure who did it, but it's definitely ported. I could/should probably up the RPM limit a bit too because it's definitely still making power up there. Probably not to 8000 for the sake of my valve springs, but at least 7500.

Yeah, I think I've just gotta get the T5 cam and buckets.
Click to expand...
A couple of questions for you:
Are you using the RSI dual spring or single spring kit? If it's the duals, you should be able to rev to 8k without issue.
Do you have any pics of the chamber and port work? I've seen a lot of very shrouded OS exhaust valves, and they can flow worse than stock.

I'm not sure what valve clearances you're running, but you can tighten up the valve lash and gain a fair bit of duration which would help the top end power. Going as tight at 0.006" IN and 0.008-0.010" EX should be fine. Bonus: the motor will sound less like a sewing machine at idle.
 
Here is the page with the K15 turbo cam about halfway down the page. https://enem.se/produkter.asp Enem lists the powerband of their cams in stages. The V15 for example is a stage one cam. The n/a version of the K15 is listed as a stage 3/4 cam. One reason I point out this cam is it's the most aggressive cam that still works with the stock cam followers. Hank Scorpio used it in his build long ago.
 
culberro said:
A couple of questions for you:
Are you using the RSI dual spring or single spring kit? If it's the duals, you should be able to rev to 8k without issue.
Do you have any pics of the chamber and port work? I've seen a lot of very shrouded OS exhaust valves, and they can flow worse than stock.

I'm not sure what valve clearances you're running, but you can tighten up the valve lash and gain a fair bit of duration which would help the top end power. Going as tight at 0.006" IN and 0.008-0.010" EX should be fine. Bonus: the motor will sound less like a sewing machine at idle.
Click to expand...

I'm using the single spring kit. I always forgot to take pictures with the head off, but here's one picture of the combustion chamber. Maybe it was RSI porting, I just don't know.

AKeELTFl.png


That's good to know. When I swap the cam, I'll tighten up the clearances to that spec.
 
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dl242gt said:
Here is the page with the K15 turbo cam about halfway down the page. https://enem.se/produkter.asp Enem lists the powerband of their cams in stages. The V15 for example is a stage one cam. The n/a version of the K15 is listed as a stage 3/4 cam. One reason I point out this cam is it's the most aggressive cam that still works with the stock cam followers. Hank Scorpio used it in his build long ago.
Click to expand...
The K15 turbo cam has a significant amount of lobe separation, pretty much the same as the RSI stage 3. My exhaust setup has very low backpressure, so I think I can afford some overlap to get some more low end torque. That's why the KL T5 cam is interesting to me.
 
yea they will probably know i mean if you want to stick with stock buckets and just get a thicker shim its just a matter of some machine work on the valves and bases of the buckets. im excited to see it make 600whp!!!! :D
 
t8fanning said:
I'm using the single spring kit. I always forgot to take pictures with the head off, but here's one picture of the combustion chamber. Maybe it was RSI porting, I just don't know.

AKeELTFl.png


That's good to know. When I swap the cam, I'll tighten up the clearances to that spec.
Click to expand...
Not to be rude, but those valves are shrouded AF. I'm almost certain a well ported stock valve head would out flow those.

Here's a 48/40 setup I did after another shop F'd up the head.

https://flic.kr/p/2mEk1u2
 
cosbySweater said:
yea they will probably know i mean if you want to stick with stock buckets and just get a thicker shim its just a matter of some machine work on the valves and bases of the buckets. im excited to see it make 600whp!!!! :D
Click to expand...
They also have solid buckets with lash caps that I'm thinking about. Since I'll be in there. It's probably worth the extra setup hassle.

culberro said:
Not to be rude, but those valves are shrouded AF. I'm almost certain a well ported stock valve head would out flow those.

Here's a 48/40 setup I did after another shop F'd up the head.
Click to expand...
It's not rude to me. I didn't do the work, and I haven't tried to change it at all. I wouldn't be surprised if a good port outflowed what I have. I've seen some Erland Cox combustions chambers and it looks similar to what you have done. I probably should get it ported properly. I just don't especially want to pull the head and wait. Maybe in the winter.
 
t8fanning said:
The K15 turbo cam has a significant amount of lobe separation, pretty much the same as the RSI stage 3. My exhaust setup has very low backpressure, so I think I can afford some overlap to get some more low end torque. That's why the KL T5 cam is interesting to me.
Click to expand...
The K15 turbo cam has split lobe separation that is still less than a n/a cam. The higher number lobe separation like 112 degrees is lower overlap than say 109. The K15 is using 111 intake and 115 exhaust so it should be good for your high power application. The turbo V15 uses 112 degrees while the n/a version V15 is 109 degrees more overlap for the n/a cam.
 
I switched up a few things and am finally happy enough with my transmission to post some results. Here's a video. It includes a short low boost (20 psi) pull. Please excuse the rattles and screwdrivers in the passenger footwell.

@RoadRacer4Life here you go ;)


I removed the HTG GCU and converted my setup to be controlled by CanTCU (https://www.canformance.net/). CanTCU uses a stock BMW TCU in the gearbox and essentially translates outputs from the ECU to what the BMW TCU can understand. This is different than the HTG GCU control method which takes full control of the solenoids in the gearbox. I could never get the HTG shifts to a point where it felt comfortable, reliable, and safe to drive on public roads.

Shifts with CanTCU are awesome. They're smooth, fast, and reliable. We had to adjust the shift points slightly in the BMW TCU as it was limiting me to 6500 rpm in manual mode because that's what the 2016 BMW 750i my TCU came from was programmed to do. Now that is fixed I can go all the way to my rev limiter. I also have BMW drivelogic modes (Eco Pro, Comfort, Sport, and Sport+) as well as some other BMW drive modes (Drive, Sport, Manual). It feels great and is working exactly like I hoped it would.

I've got the Motec dash displaying drivelogic mode, drive mode, and gear. You control P/R/N/D and drivelogic mode with the 6 button keypad right below the shifter. You can only see the top bit of the keypad in the video unfortunately.

CanTCU relays blip/cut requests from the TCU to the ECU, and Motec handles the blips and cuts. The cuts maybe need a little softening at low throttle inputs, but the blips feel pretty good in general.

The only complaint I have about the setup now is that I don't have a simulated clutch pedal. CanTCU currently doesn't support that for 8hp transmissions. It's a small price to pay for reliability and smoothness in my application though.

I think I might try to get my torque converter modified for higher stall in the winter. It's a diesel torque converter and really is too tight for my application. I've thought about getting an 8HP50 torque converter but I'm not sure if the clutches in my 8HP75 one are stronger or not. I need to do a little more research.
 
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