Loose, what does GM run (plugs) in these bullets?
Loose, what does GM run (plugs) in these bullets?
Loose those numbers hp/lbft are at what rpm?
759NRNG wrote: Loose those numbers hp/lbft are at what rpm?
Hp @ 5490 and torque @ 4298. The torque number is interesting because with the stock wastegate, boost only started at 4000 rpm but now it starts around 2700 rpm. I can't wait to see what it actually feels like on course. As for plugs, GM uses AC Delco plugs that are $25.00 Each, so there is something special about them.
L, the stock specs show 295lb/ft @2400r's for the LHU....iffen I were as dedicated a cone annihilator as your self, I think I'd want massive doses of low end grunt without all the upper rpm drama. Am I not grasping the tune versus boost scenario for this exercise....sorry I'm looking at this like an oil burner (diesel).....massive lb/ft at stupid low rpm.
In reply to 759NRNG:
That is interesting. I may be mistaken but I think hp is measured and torque is calculated (or vice versa) and the formula is horsepower x 5252 over rpm. The higher rpm for torque might be the result of having a tune that produces so much more power than stock and a redline raised by 700 rpm, I'm not sure. Here is a picture I took of the graph and keep in mind that it was misfiring pretty badly at high rpm
[URL=http://smg.photobucket.com/user/loosecannon/media/MGB-GT/IMG_9999_zpscdyvhwlv.jpg.html]
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I have made a lot of changes since the last time I drove the car. Lower control arms, front sway bar, floor, engine, fuel system and oil accumulator are all changed or new and the way this season has gone, I was really nervous about all of it working together. I took the car out on an unused road and did some hard acceleration, turning and braking and it felt great. I think the smoke is because oil is getting drawn through the air/oil seperator and sucked into the engine. When I got home I changed it back to the way it was routed last year so I think that problem is solved. I feel a lot better about the car now. The handling is so sweet and I didn't even mess with suspension settings, I just drove it. I also tried to get the inside rear tire to spin but couldn't, but the road wasn't as grippy as the concrete in Lincoln so we'll see about that. Oh yeh, I also had a new adjustable wastegate in it with the .8 bar (11 psi) spring in and was under the impression that this meant that it started to open at 11 psi-nope, turns out it starts to open at 4 psi and is fully open at 11 psi. I swapped that out when I got home for one that starts to open at 11 psi and is fully open at 17 psi.
loosecannon wrote: In reply to 759NRNG: That is interesting. I may be mistaken but I think hp is measured and torque is calculated (or vice versa) and the formula is horsepower x 5252 over rpm. The higher rpm for torque might be the result of having a tune that produces so much more power than stock and a redline raised by 700 rpm, I'm not sure. Here is a picture I took of the graph and keep in mind that it was misfiring pretty badly at high rpm [URL=http://smg.photobucket.com/user/loosecannon/media/MGB-GT/IMG_9999_zpscdyvhwlv.jpg.html]
Dynos measure torque. HP = TQ x RPM / 5252. There's more in it. No way peak HP comes in under 5,000 RPM. Clean up your spark issues and I'm betting peak HP is somewhere between 5,500 and 6,000 with all the boost. By the way, it could be the boost pressure is "blowing out" the spark.
In reply to Jerry From LA:
I hope you are right. I put stock plugs back in and gapped them to .027" and it showed no signs of misfire during the road test. I can't wait to try it with the new wastegate spring.
I pulled the Verano engine apart today and just as I predicted, the rings lands are shot, probably from too much boost
[URL=http://smg.photobucket.com/user/loosecannon/media/MGB-GT/IMG_0115_zpsy2wqd5kp.jpg.html]
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And that missing land is in the oil pan?
In reply to 759NRNG:
Seems to be little pieces in the filter, oil galleries and mesh screen of the cam actuators
Are the block and crank salvageable ?
In reply to 759NRNG:
The crank looks mint and I'll know about the block once I measure the bore. It's not an engine you want to bore over because the walls are too thin. ZZP has blocks if I need one. I have a shifter kart for sale and if it sells, I think I'm going to get some good parts for this one.
Ring ends butted?
Horsepower is a mathematical calculation used by salesmen to impress farmers. It worked so well we cant get rid of it....
Jerry From LA wrote:loosecannon wrote: In reply to 759NRNG: That is interesting. I may be mistaken but I think hp is measured and torque is calculated (or vice versa) and the formula is horsepower x 5252 over rpm. The higher rpm for torque might be the result of having a tune that produces so much more power than stock and a redline raised by 700 rpm, I'm not sure. Here is a picture I took of the graph and keep in mind that it was misfiring pretty badly at high rpm [URL=http://smg.photobucket.com/user/loosecannon/media/MGB-GT/IMG_9999_zpscdyvhwlv.jpg.html]Dynos measure torque. HP = TQ x RPM / 5252. There's more in it. No way peak HP comes in under 5,000 RPM. Clean up your spark issues and I'm betting peak HP is somewhere between 5,500 and 6,000 with all the boost. By the way, it could be the boost pressure is "blowing out" the spark.
Not all dynos measure torque. Inertia dynos measure HP. However, that's a Mustang dyno and they do measure torque and calculate HP. The reason that graph looks weird is that the x axis is time and not RPM. That's usually done when the ignition pickup (that's used to measure RPM) isn't working and the dyno operator doesn't want to take the time to perform an engine RPM to roller speed calibration.
loosecannon wrote: I pulled the Verano engine apart today and just as I predicted, the rings lands are shot, probably from too much boost [URL=http://smg.photobucket.com/user/loosecannon/media/MGB-GT/IMG_0115_zpsy2wqd5kp.jpg.html]
That looks like classic detonation damage which may have been from too much boost or too much ignition time and/or not enough fuel for the boost.
APEowner wrote:loosecannon wrote: I pulled the Verano engine apart today and just as I predicted, the rings lands are shot, probably from too much boost [URL=http://smg.photobucket.com/user/loosecannon/media/MGB-GT/IMG_0115_zpsy2wqd5kp.jpg.html]That looks like classic detonation damage which may have been from too much boost or too much ignition time and/or not enough fuel for the boost.
+1.
One other note- that black smoke in the video looks like it's running REALLY rich- not oil. Are you taking engine data when you are driving the car?
And the reason I ask- DI engines have this really odd phenomenon of pre-ignition at very high loads. While the physics are similar to other PI of old, this one tends to set up what some label as Mega Knock- and that does a number destroying engines. And seeing that many OEM's put different, hardened, materials on the first ring land- it's pretty common across all of us. That particular failure looks very much like Mega Knock- I've seen that a few times from experiments. Although, ours had holes eroded in the sides of the piston- so it was farther than you took it.
Anyway, I'd talk to the ECU tuner to see if you can record while driving, and that can be used to feedback info to them.
As for the power data- that torque curve should be pretty flat from 2500 up to 4000-5000rpm, not a single peak like that.
alfadriver wrote: As for the power data- that torque curve should be pretty flat from 2500 up to 4000-5000rpm, not a single peak like that.
The x axis on that graph is time not RPM
APEowner wrote:alfadriver wrote: As for the power data- that torque curve should be pretty flat from 2500 up to 4000-5000rpm, not a single peak like that.The x axis on that graph is time not RPM
Thanks for the clarification- looking again, the light blue line in the background is engine speed. So the same thing still applies.
alfadriver wrote:APEowner wrote:Thanks for the clarification- looking again, the light blue line in the background is engine speed. So the same thing still applies.alfadriver wrote: As for the power data- that torque curve should be pretty flat from 2500 up to 4000-5000rpm, not a single peak like that.The x axis on that graph is time not RPM
Yeah, even with the weird graph format it's obvious that there's something not right with the way the engine is running.
The next time that dyno is used it would be good to take the time to calibrate the roller speed to RPM. Just looking at peak numbers only tells a small part of the story. The shape of the curves is also important.
We ran that engine out of fuel on the dyno the day before it finally let go. The mechanical pump was failing and we didn't catch it in time. It was run lean and overboosted so no surprise that this old motor let go. I do often datalog while driving around and everything looks fine on the logs.
Went out for a Test N Tune on the think strip of asphalt we call an autocross site. Right out of the trailer the car felt better than it has ever felt. I adjusted the brake balance a couple of clicks but that's all I needed to do. The smoke was completely gone and there was lots of power. After a few back to back runs the engine got hot enough to start spitting out the overflow so I just packed up and went home, but I am thrilled with how the car felt. I suspect that my new routing of the coolant hoses has caused air to get trapped there so I will address that this week. Here is a video with the engine data on the right. And Yes, I know my driving is crap, I am way out of practice and am losing time through some bad habits picked up in karting
Boost coming on below 3000rpm ??
In reply to 759NRNG:
Yes, depending on conditions it has had 5 psi as low as 2800 rpm
My overheating issues seem to be something deeper than hose routing. I carefully routed hoses to mimic the stock routing and purged the system of air but when the temperature came up, pressure in the cooling system would pop the 21 psi radiator cap. I tried different caps, I checked if the water pump was pumping and I pressure tested the cooling system (it loses half a psi every 2 minutes). The major concern is the air bubbles that come out of the coolant when the engine is running, a sign of a bad head gasket or a cracked head. I have an extra head so I'm going to put new springs in it and install.
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