Down on Power After Head Intake Swap
DA was likely similar same track, maybe hotter, but that would not make a huge difference.
I just measured temps at the exhaust header. I could not perceive a big difference bank to bank when idling. All were about 230F 5/6 were about 250F but I think that is just because of tight packaging there. I would expect the difference would be quite noticeable if a cylinder had an issue. Anyone know how much difference is significant?
I just measured temps at the exhaust header. I could not perceive a big difference bank to bank when idling. All were about 230F 5/6 were about 250F but I think that is just because of tight packaging there. I would expect the difference would be quite noticeable if a cylinder had an issue. Anyone know how much difference is significant?
When I raced micro-sprints it wasn't uncommon to see 10-30 degrees difference at idle and around 50-80 degree spread just after a race but this was also a carbed setup on methanol. I didn't use it so much as tuning tool but it was just a quick way to see if there were any obvious problems. I also use it to help diagnose a engine with a miss or dead cylinder/ check cooling system and so on.
TECH Regular
Joined: Sep 2013
Posts: 403
Likes: 15
From: Dundee, MI
DA was likely similar same track, maybe hotter, but that would not make a huge difference.
I just measured temps at the exhaust header. I could not perceive a big difference bank to bank when idling. All were about 230F 5/6 were about 250F but I think that is just because of tight packaging there. I would expect the difference would be quite noticeable if a cylinder had an issue. Anyone know how much difference is significant?
I just measured temps at the exhaust header. I could not perceive a big difference bank to bank when idling. All were about 230F 5/6 were about 250F but I think that is just because of tight packaging there. I would expect the difference would be quite noticeable if a cylinder had an issue. Anyone know how much difference is significant?
I only had time to pull one plug... that plug looked good. Only potential issue is the plugs are TR6 gapped to .035, I see that 0.05 to 0.06 is recommended. So when I pull them to check I'll regap them to 0.055. Anyone have experience with a big power drop with a small gap?
Seems to be hissing from the back on the intake, I may have a vacuum leak. Vacuum is 12 at idle. I'll likely pull the plugs, pull the intake and pull the valve covers. If no trouble found I'll head to a experienced tuner.
Seems to be hissing from the back on the intake, I may have a vacuum leak. Vacuum is 12 at idle. I'll likely pull the plugs, pull the intake and pull the valve covers. If no trouble found I'll head to a experienced tuner.
TECH Regular
Joined: Sep 2013
Posts: 403
Likes: 15
From: Dundee, MI
I only had time to pull one plug... that plug looked good. Only potential issue is the plugs are TR6 gapped to .035, I see that 0.05 to 0.06 is recommended. So when I pull them to check I'll regap them to 0.055. Anyone have experience with a big power drop with a small gap?
Seems to be hissing from the back on the intake, I may have a vacuum leak. Vacuum is 12 at idle. I'll likely pull the plugs, pull the intake and pull the valve covers. If no trouble found I'll head to a experienced tuner.
Seems to be hissing from the back on the intake, I may have a vacuum leak. Vacuum is 12 at idle. I'll likely pull the plugs, pull the intake and pull the valve covers. If no trouble found I'll head to a experienced tuner.
A leak
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Verdad Gallardo I think there is a reason that many posts you never find out the resolution to the problem. Because it is something stupid. My problem appears to have only been a shitty mechanic (me). I found two plugs were only finger tight, oops. I expect this is my only issue, I think maybe the hissing I could hear was exhaust escaping thru the plugs.
Biggest difference during my test drive was mid-range grunt. Guess I gotta hit the track again.
Biggest difference during my test drive was mid-range grunt. Guess I gotta hit the track again.
UPDATE
Two loose plugs was the issue, car was running great. I found out the hard way that I must have had a leak between the injectors and the intake as well.
My car is always garage kept. This weekend it was outside and rained very hard. I have noticed when I wash the car the cowl leaks water right onto the engine. So, when it rained very hard right onto my engine rain water leaked into the #6 cylinder through the lower injector o-ring. When I went to start the car the next day it hydro-locked that cylinder and destroyed the starter. Tonight I pulled the plugs and it still won't turn over. I think I have broken a piston. I'm ready to pull the head, tomorrow... SUCK
Two loose plugs was the issue, car was running great. I found out the hard way that I must have had a leak between the injectors and the intake as well.
My car is always garage kept. This weekend it was outside and rained very hard. I have noticed when I wash the car the cowl leaks water right onto the engine. So, when it rained very hard right onto my engine rain water leaked into the #6 cylinder through the lower injector o-ring. When I went to start the car the next day it hydro-locked that cylinder and destroyed the starter. Tonight I pulled the plugs and it still won't turn over. I think I have broken a piston. I'm ready to pull the head, tomorrow... SUCK
Dude that sucks hard. You might be lucky it never fired. When I hydrolocked my 97, it actually fired, made a god aweful cracking sound, and oil spewed all over my driveway. It blew a hole in the block the size of a baseball
Thanks, it really does suck.
Pulled it apart last night and the piston is fine. The rod must be bent cause TDC is lower than it should be and the engine won't rotate a full cycle, the rod must be hitting something. If I bent a rod seems like the force was pretty extreme and I may have damaged something else that may not be possible to see.
So I'm just weighing my options right now.
Pulled it apart last night and the piston is fine. The rod must be bent cause TDC is lower than it should be and the engine won't rotate a full cycle, the rod must be hitting something. If I bent a rod seems like the force was pretty extreme and I may have damaged something else that may not be possible to see.
So I'm just weighing my options right now.
The rod is probably hitting the very bottom of the cylinder wall. IDK if its worth it to you to drop the oil pan and try to get that piston and rod out and see the cylinder condition or if at that point, you're just thinking to swap the short block.
The two loose spark plugs does explain a lot - and probably was responsible for being 80 down on power. Shame you never really got to measure it.
The two loose spark plugs does explain a lot - and probably was responsible for being 80 down on power. Shame you never really got to measure it.
