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This thing will be back on the same chassis dyno at engine power systems on Wednesday. I did finally drive it with the tune from before rebuilding, just added some boostane for safety. It rips.
Stay tuned for part 2 but in the heat
I want to put my new motor on an engine dyno. Just to have a comparison and do a little break in before installing it in the car. Where'd you go for that?
I hope to be at 700HP. The heads are flowing over 400cfm on a 4.070" bore... God knows what they flow on a 4.185" bore. Pretty similar cam spec to your build. Using a ported FAST Med-Length runner. So I might not be able to keep the RPM up the same but might pick up a little midrange.
I went to Dimond race engine in Hammond Louisiana . He also did all my machine work and assembled shortblock.
2 things I don't know how much it effects hp on the dyno but he doesn't have that air duct that comes from outside but did have doors open.
He did tell me if I had a big filter or a velocity stack it would have read about 20 higher.
Also water temp was 120. He feeds it from garden hose and never goes to full temp. Oil temps hot though.
We made 18 pulls ,its broke in nice for sure
Well I cancelled the dyno for tomorrow. Drove the car and it has a misfire since relocating the coils and the valve covers are leaking way more when I run it hard.
I asked Geoff if he would be to upset if I cancelled since I dont want to waste either of our time.he said no problem so tomorrow I'll be changing the valve covers and pulling plugs to see what they look like. Go through the valve train and check adjustment.
Other than the miss at wot, it actually drives good. Transmission feels solid and converter drives efficient. Lock up at 75 only dropped 200 rpm.
Will reschedule when all is good and I'll do street tuning on it first.
If you do not see anything you think you might need to slightly close the gap? Cylinder pressure might be blowing out the spark
I did have #1 plug wire not getting a good connection and when I pulled the plug it was wet.i changed that one with some spares I had.
Went and drove after and its much better but very lean. It has boostane in the tank and I've read boostane leans the mixture.
Plan for tomorrow is change all the plugs and set gap at .036 and add to the ve table so its rich then dial it in from there. Changing the valve covers before driving again and while off im going to check valve lash
Yeah. I ran 055 gap and closed to 035. But you already thought of that. I just could not figure any other reason you would have a misfire since you paid so close attention on your build.
What coils do you have? I have a buddy with an ls3 c5z with 100k miles on it. Out of nowhere with a small cam the thing started to reek at idle - like mosquito fogger level - where it was very clean burning before.
Pulled the plugs and one was wet, and one was completely fouled with buildup.
Put a set of late model coilpacks on it and immediately the smell went away and idle is stronger.
When you look at the plugs, where is the plating burned back to on the ground strap? You want it burnt right to the middle of the bend. If it is too close to the tip the plug is too cold, and if it burning back toward the threads it is too hot.
I wouldn't jump to a heat range 7 straight away unless the engine is showing you that it wants a colder plug. A swap from a TR6 projected to a BR7 non-projected tip is a double whammy... There are TR7 projected tip plugs as well that might be a better intermediary. Ready in corvette forum there's a lot of back and forth about plug type, and what works. Kind of muddies the water when people with boost jump in the topic.
That said, I bought some coil packs from Pantera EFI, and I'll be running Iridium plugs for the first time on my next engine. I want the strongest idle I can get with the stupid ~30 degrees of overlap I'm going to have.
What coils do you have? I have a buddy with an ls3 c5z with 100k miles on it. Out of nowhere with a small cam the thing started to reek at idle - like mosquito fogger level - where it was very clean burning before.
Pulled the plugs and one was wet, and one was completely fouled with buildup.
Put a set of late model coilpacks on it and immediately the smell went away and idle is stronger.
When you look at the plugs, where is the plating burned back to on the ground strap? You want it burnt right to the middle of the bend. If it is too close to the tip the plug is too cold, and if it burning back toward the threads it is too hot.
I wouldn't jump to a heat range 7 straight away unless the engine is showing you that it wants a colder plug. A swap from a TR6 projected to a BR7 non-projected tip is a double whammy... There are TR7 projected tip plugs as well that might be a better intermediary. Ready in corvette forum there's a lot of back and forth about plug type, and what works. Kind of muddies the water when people with boost jump in the topic.
That said, I bought some coil packs from Pantera EFI, and I'll be running Iridium plugs for the first time on my next engine. I want the strongest idle I can get with the stupid ~30 degrees of overlap I'm going to have.
I have 30 degrees overlap as well. It was idling beautifully so I think new tr6 will be fine, maybe I should try the iridium model
TR6IX is what you want if you want to try the iridium fine tip electrode. There's no downside to them other than a little more cost. It is a fine tip electrode that will run better at idle and light load where you have a lot of dilution from the cam overlap.
Unlikely to see any difference in performance under load.
06-09-2019, 04:23 PM
