How are these compression numbers?
#1
How are these compression numbers?
I'm gonna get a Jspec and the numbers sound pretty good.
It had 85 psi on front and 95 on back.
I know 95 is great but the 85 is borderline right?
I saw some other thread about how low comp engines put out lower numbers but this is around what my GTU was doing.
It had 85 psi on front and 95 on back.
I know 95 is great but the 85 is borderline right?
I saw some other thread about how low comp engines put out lower numbers but this is around what my GTU was doing.
#4
I've heard 95 isn't bad.
Especially since I'm getting a S4 Jspec.
I'm doing a NA-TII conversion so I need the long block before I can rebuild.
I also don't have the money right now to rebuild. I plan to get it rebuilt in around 2-3 months when I will have money again. You think these numbers would last for atleast 2-3 months.
Especially since I'm getting a S4 Jspec.
I'm doing a NA-TII conversion so I need the long block before I can rebuild.
I also don't have the money right now to rebuild. I plan to get it rebuilt in around 2-3 months when I will have money again. You think these numbers would last for atleast 2-3 months.
#5
No, that is borderline already dead. I wouldnt install it, or even buy it unless it was just as a core for a rebuild. It's probably worth $300 (longblock) as a core. My TII is at 100 100 and I would rebuild it right now if I had the time and money. I have to wait till I graduate this summer though.
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#8
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I would just keep looking. $1100 sounds a little steep for a engine with compression like that. Even for a J-Spec. It's going to cost you more money anyways if you buy that engine and rebuild it, than if you just bought an engine with good compression for some more money
#10
I have to get my car running by mid December at the latest. It was my daily driver and right now I'm driving my 88 SE but this thing feels like it will die any day now and I work 32 miles from home.
Also like I stated above. If I could buy a Long block rebuilt engine I would do it in a heart beat but I am doing a TII conversion and need ALL the parts.
Also like I stated above. If I could buy a Long block rebuilt engine I would do it in a heart beat but I am doing a TII conversion and need ALL the parts.
#12
Originally posted by Digi7ech
I have to get my car running by mid December at the latest. It was my daily driver and right now I'm driving my 88 SE but this thing feels like it will die any day now and I work 32 miles from home.
Also like I stated above. If I could buy a Long block rebuilt engine I would do it in a heart beat but I am doing a TII conversion and need ALL the parts.
I have to get my car running by mid December at the latest. It was my daily driver and right now I'm driving my 88 SE but this thing feels like it will die any day now and I work 32 miles from home.
Also like I stated above. If I could buy a Long block rebuilt engine I would do it in a heart beat but I am doing a TII conversion and need ALL the parts.
#13
I need longblock cause I don't have the engine in my car.(Need Manifold/turbo/IC/injectors/etc....)
Also a little clarification on the compression results.
Will a NA high compression engine give higher numbers than the low compression 8.5 TII engine?
Or is this completely irrelevent? My GTU pulled high 80's/low 90's and it's NA.(Months before it blew a coolant seal)
Also a little clarification on the compression results.
Will a NA high compression engine give higher numbers than the low compression 8.5 TII engine?
Or is this completely irrelevent? My GTU pulled high 80's/low 90's and it's NA.(Months before it blew a coolant seal)
Last edited by Digi7ech; 11-24-03 at 07:29 PM.
#14
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Originally posted by ZachSpazz
90 PSI is low. Good compression is anywhere from 110-120 PSI.
Look elsewhere, or consider a rebuild.
90 PSI is low. Good compression is anywhere from 110-120 PSI.
Look elsewhere, or consider a rebuild.
#19
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Originally posted by bcty
120 -130 from factory.. below 90 send er back.. you can get a good j-spec around 100=110 compression.. just look harder
120 -130 from factory.. below 90 send er back.. you can get a good j-spec around 100=110 compression.. just look harder
#21
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85-90 is a good compression for a used motor. Most places post WET compression numbers and say 110PSI when in reality if they would have done a normal test it would be lower. Also most people use a non Mazda comp tester and think they can do it that way when it can get close but never be correct.
#23
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I'm sure it would run and probaby run fine, but there is still 10psi difference between rotors. My S4 NA engine had 90 on both and it ran great. I haven't tested it since I rebuilt because I don't care. It has been running better than before and I've got better things to measure!
#24
FC Mobsta
Originally posted by 88IntegraLS
I'm sure it would run and probaby run fine, but there is still 10psi difference between rotors. My S4 NA engine had 90 on both and it ran great. I haven't tested it since I rebuilt because I don't care. It has been running better than before and I've got better things to measure!
I'm sure it would run and probaby run fine, but there is still 10psi difference between rotors. My S4 NA engine had 90 on both and it ran great. I haven't tested it since I rebuilt because I don't care. It has been running better than before and I've got better things to measure!