how's my compression

[99 gst spyder]

cylinder 1 is 130
cylinder 2 is 150
cylinder 3 is 150
cylinder 4 is 150


i did a wet test on cylinder 1 and it gave me 190

82k mile on motor

should i be worried?

 

[killer_eclipse]

what motor is it you are working on?perfect is 178 and service is 133 on a 2g
and 164 is perfect and the service limit is 121 but for it to jump that much on a wet test is kinda weird did you do the compression test correctly was the engine up to normal operating temp?

 

[99 gst spyder]

what motor is it you are working on?perfect is 178 and service is 133 on a 2g
and 164 is perfect and the service limit is 121 but for it to jump that much on a wet test is kinda weird did you do the compression test correctly was the engine up to normal operating temp?

it is done with my 6 bolt 91 talon awd turbo.it did jump alot on wet test. the service limit is 120 for a 1g turbo. i went for a drive around the block before i did the compression test. it's fully warm. there was little oil on two of my spark plugs too. idk why.

should i be worried driving it with that compression?

 

[killer_eclipse]

well i would be about the oil on the plugs honestly its all up to you 150 isn't terrible the one with 130 is kinda a concern if it were me i would start preparing for a rebuild....

 

[99 gst spyder]

should i be safe with the compression though. not looking foward for rebuild. what can go wrong with bad compression? can blown head gasket cause any of these?

 

[TheGreatGSX]

I wouldn't personally worry about a rebuild, I've heard of several people under the service limit on every cylinder and the car lasting another 100k miles. I don't believe a blown head gasket could cause one cylinder being lower compression, I believe it would be the cylinders piston ring. (Someone correct me if I'm wrong) Because the oil will form a temporary seal.

If you were to check anything, I'd check the piston ring on that 1 cylinder, I wouldn't worry about the others. Any problems with the car other than this?

 

[99 gst spyder]

I wouldn't personally worry about a rebuild, I've heard of several people under the service limit on every cylinder and the car lasting another 100k miles. I don't believe a blown head gasket could cause one cylinder being lower compression, I believe it would be the cylinders piston ring. (Someone correct me if I'm wrong) Because the oil will form a temporary seal.

If you were to check anything, I'd check the piston ring on that 1 cylinder, I wouldn't worry about the others. Any problems with the car other than this?

all my spark plugs are bad. all four have hole on top of them. suppose to be flat. you can twist it open. little oil in numbers 2 and 4 plugs. car bogs alot at high boost around 5k rpm causing my o2 dump to pop very loud.

 

[ed_dogg23]

Drive it dude. Ive put 20k on my 1g with #1 120, #2 120, #3 100, #4 120. It runs good still. Oh and the car has 125k.

 

[biker_joe89]

You are definitely not going to get the performance you would with the better compression. But if you are not that worried about it. It will likely still hold for a long time. I am running 150 135 150 150 in my 93 right now and have been since I checked it in december last year. Still very reliable, and running strong. Plan to get this summer out of it and be putting a built 6 bolt in it next winter.

I believe it would be the cylinders piston ring. (Someone correct me if I'm wrong) Because the oil will form a temporary seal.

That is correct

 

[TheGreatGSX]

all my spark plugs are bad. all four have hole on top of them. suppose to be flat. you can twist it open. little oil in numbers 2 and 4 plugs. car bogs alot at high boost around 5k rpm causing my o2 dump to pop very loud.

Have you replaced your valve cover gasket recently? I had that issue when I first bought mine and the valve cover gasket was the culprit, I'd replace that, get new plugs, check for boost leaks, how much boost are you running?

 

[99 gst spyder]

it sound good that i'd still be able to drive it like that. good to here. yeah i'm going to replace the head gasket and arp head studs and all spark plug on it. the one in there now are shot badly.

maybe valve cover gasket to. maybe spark plug gasket are shot too that's why i have oil in my spark plugs. do you think so?

what spark plugs do you guys recommend? thinking of ngk bpr7es or bpr6es.

i just recently put in a 16g and tubular manifold in the car. so i'm guessing running stock boost. usually 16g waste gate are set at minimum 10 psi. here is a weird thing though. i have a boost gauge in and did 2nd gear pull. the meter went all the way up to 20 psi then i stop that gas. not sure why. can i add a boost controller to lower the boost? or do something to the waste gate?

thanks for everyone's input.

today i encounter something new. i did a wet test yesterday on cylinder 1. is the oil suppose to stay in the cylinder?

today i install some brand new ngk bpr7es in. it smoked blue like crazy on cold start up then slowly turns white when it warmed up. it has this small idling problem too. i got the laptop hooked up and drove it regularly. i'm getting up to 6 counts of knock retard just driving it regularly up to 3500 rpm. (only). so i stop driving it. remember i have coil on plug too if it makes any differences on the gapping. oh i did gap them to .028. anyone please help me out.



the old spark plugs were gap to around .034-.040 but they are messed up.