Home Built Dyno/Junkyard Turbo 350 Help

[ka67_72]

I've built a water brake dyno and have a junkyard turbo 350 on it. This is my first experience with a dyno so I have no idea of what I'm doing. I have a mild 350 on that's proving to be way more mild than I'd like it to be. The motor currently has a 600 cfm 4160 on it to break it in. Exhaust is blowing through the turbo but it's running N/A for now.

350 4 bolt .030 over
Scat cast steel crank
Forged Procomp rods
Probe 12.5 cc dish forged pistons
Comp Turbo Cam, http://www.compcams.com/Company/CC/c...?csid=131&sb=2
291 Double Humps, 1.94 int, cleaned up and port matched. Valve guides are a little sloppy.
Performer intake, port matched
MS-II running ignition only for now.
Rams Horn cast iron manifolds
2-3/8" OD stainless crossover
Single HX-55 turbo

I made a few pulls at part throttle standing next to it before my throttle cable arrived. It made around 400 lb-ft between 2000-4000 rpm. I hadn't done a good cal on my load cell, but it was only off about 10lbs. I then installed new springs and set the timing to match the Megasquirt. I started at 36 degrees at WOT. It was making 250 lb-ft. I've slowly increased timing to 42 degrees and it's making a peak of 360 lbs. I have an advance timing light and it agrees. Do I add more timing or is there something going wrong with the distributor. The plugs all look fine. I currently only have the data logged from the MS and torque, RPM, and two egt's at a time from the dyno. I just pulled the cam. It looks and measures fine. It's now back in and degrees out good straight up.

Here's a video. In the second pull I accidentally shut off the water. It doesn't normally make that much steam. The setup is about as junkyard as it gets.

http://www.youtube.com/watch?v=JqEvsUcbPSY

Thanks,
Kevin

[min301]

Remember, things will change drastically when you boost it.

N/A those heads will want more ignition, they are inefficient.
Boosted, the timing will need to be backed off.

[ka67_72]

I've been very tempted to stick the EFI on it and start adding boost. I've never had anything with an actual turbo cam before. I've just run small N/A cams. I'm hoping the issue is the restrictive exhaust and lack of overlap. I was running these heads with other internals and cam in the car before. It was 9.7:1 and I had the timing in the upper 40's and it ran great until it broke a piston and all the top rings on the driver's side. Other than the broken parts, it didn't show any signs of detonation. I also had this top end on an N/A 327 in my 67 Chevelle for years and it ran great.

Thanks,
Kevin

[min301]

Talk with Scott Clark , he can add alot of information with the MS.

[TC]

Talk with Scott Clark , he can add alot of information with the MS.

That would be DieselGeek.........

[dieselgeek]

First off, that's a badass setup and I want to hear more about it!!

Second, as long as the timing light shows close to what your MS believes for timing, and you've tested it at both low and medium/high RPM, then you are good to go. I see it gets very rich at the end of the pull.

So is the question "why did I lose a bunch of torque" ? I don't see anything in your log that seems strange, but I am curious what battery voltage is doing during the pull - not bouncing around too much hopefully?

I am super interested in the homemade dyno setup, I know a few others here would be as well!

-Scott

[65RHDEER]

Way cool dyno, like Diesel said tell us more we all need a dyno in the garage.

Looking at your uploads on YouTube you have a few interesting thing going on .

.

[JeffMcKC]

I cant tell colors well, but it looks like it started to build intake vacuum on the pull, this means its restricted like to small of carb. Thats also why it went rich

[JeffMcKC]

First off, that's a badass setup and I want to hear more about it!!

Second, as long as the timing light shows close to what your MS believes for timing, and you've tested it at both low and medium/high RPM, then you are good to go. I see it gets very rich at the end of the pull.

So is the question "why did I lose a bunch of torque" ? I don't see anything in your log that seems strange, but I am curious what battery voltage is doing during the pull - not bouncing around too much hopefully?

I am super interested in the homemade dyno setup, I know a few others here would be as well!

-Scott

And more about your dyno!!!

[seanm]

Running the turbo without the cold side connected can overspeed the turbo and cause failure. Trying to cram all the exhaust through the turbine is a definite choke point.

[ka67_72]

AFR was dropping down to the low 11's in the video but hat was because of timing. The plugs were fouling and I was blaming the worn guides. I want new heads but I think these should be enough for this project. With the timing at 42 it's reading in the low to mid 12's and the plugs are happy. I can add some kind of restrictor to slow the turbo. I have the exhaust running through the turbo and then through a large muffler I made out of a 40 gal water heater in an attempt to not disturb the neighbors. So should I just keep adding timing until it starts to fall off?

Thanks,
Kevin

[ka67_72]

Here's the log with voltage. The gauge you were seeing almost bottoming out in the video was AFR.

Thanks,
Kevin

[Cyclone03]

Your beating your head against the wall trying to do anything above 3000 rpm at WOT blowing through the turbo.
Running the cold side open will kill it too as said above.I did that on an SVO Mustang way back when.I didn't clamp the hose in place after a hard run the turbo squeked to a stop.

[DanStokes]

I'm a retired dyno guy (I did both chassis and engine dyno testing for the EPA and wrote a comprehensive dyno article for HRM back in 2000. Squirrel has a version he can send you electronically if you're interested.

Anyhow, LOVE to know more about the dyno. The PAU looks like a commercial unit as does the software, judging by the displays. Am I on the right track?

A quick safety note - I wouldn't put anything important radially in line with the dyno. Anything that fails (even just a belt) will fly off in an unpredictable radial direction and I'd hate to see that pretty Jag get dented or worse!

A guy here in town has a Stuska that I don't think gets used much, if at all. I keep lusting after in it my heart (Jimmy Carter). No clue if he'd part with it but I sometimes think of waving a $1K bill under his nose. Of course, that's $1K no longer available to build the race car......

Dan

[ka67_72]

Dan,
I would like to see the article.

My brake is made from 53 pieces of 3/8" and 1/4" steel I had laser cut out. I tried brazing but ended up welding it all together. I'm using an MS-II for some data logging, a Futek load cell, an Opto22 Snap system pieced together off ebay, and a few homemade circuits for the rest. Excluding the Megasquirt, I have $1050 in it and have a bunch of tubing left over. The Opto is currently logging torque, rpm, and two egt's/thermocouples at a time. I want to collect more data but the Opto stuff is expensive new. The brake leaks a little water on occasion, but I placed the bearings away from the $3 shaft seals to protect them some. I didn't know how the water would behave in it so it has fittings everywhere. My intent was to recirculate the water through some radiators to avoid using a large water tank. Right now I'm running off one water hose.

Short of a block wall or steel plate, what do you think would be adequate to stop any ejecta from the motor? I definitely don't want to damage anything else if it lets go. I have it boxed in to cut down on the noise and hadn't even considered something as simple as a belt being an issue. I'll be sure to point it away from everything from now on. I know it's not very Bangshifty but this motor is out of the Jag.

Thanks,
Kevin