newly rebuilt engine - poor compression figures

[12at]

Ive seen this all before... Its the apex seal blame.... inmho you cant go wrong with a set of mazda seals and a good builder..

[BlitzBoy]

sounds like rear went lean and saw det, as I said before flow test the injectors

[BlitzBoy]

Ive seen this all before... Its the apex seal blame.... inmho you cant go wrong with a set of mazda seals and a good builder..

Well in this case the apex seals have actually done their job and saved the engine components from the det episode and not damaged the plates or spat a seal through the turbine housing of the turbo. So in this case poor compression was not due to the seals fault but due to a fuelling problem in the rear rotor imo

[DR SCHNITZEL]

This forum is mad.
 
It seems it is starting to become informative again after an episode of tosh. another good thread .

[davehg]

with comp figures as random as that i would check all side seal clearances one at a time. seems to me like they have not been clearanced correctly hence the difference in comp on every face.

[PGiljevic]

Another PTS horror story

Spoke with a customer last week who contact me out of desperation, his story as follows.

First engine build on PTS engine failed on initial rolling road dyno tune!
Engine taken out and sent to another "specialist" who put in new PTS along with all recommendations by Peter Glover (backyard maker of this sh&t product).

Engine literally drowned in degummed caster oil as per PTS instruction, and fuel mixed with 10% methanol to aid longevity. Made 585bhp @ 8500rpm on 20psi boost (reputable engine dyno), this is a road car that is street raced on ocassion. Now remember this is pretty low duty maximum power use in the scheme of things.

Exactly 2000km of road running the engine is trash again (very low compresion and the seals are f7cked AGAIN) and PTS simply say "they are NOT road suitable apex seals and we dont ever sell them as such!" and hang up the phone LOL.

These pieces of sh7t DO NOT LAST IN ROAD CARS at high power!!! I have seen this and been told it many times by people who are just sick and tired of constantly wasting time taking engines in and out, and then paying to repair something that should still be running. Its a false economy, you are actually paying a metric dick load more constantly fixing something that on stock Mazda apex seals would still be running :rollin

[suba]

An update on this:

engine is now back in the car with replaced corner seal and new rear housing, I\'ve kept the PTS apex seals as I dont want the additional expense of replacing them at this time.  If I get 20-30,000 miles from them then I\'m happy with that before a strip down and inspection.

It was compression tested cold before being installed - injector were also flow tested and cleaned, though the reading from them were fine.  Compression was fine, and consistent between rotors and chambers.

I\'ll put 200 miles on the engine to bed in the seals before mapping is finished.:Thumbs-up

[PGiljevic]

Keep us updated with a running log of exactly how much performance work you do at high power (to get an idea of the stress level they are under for your targeted engine life) and also a running log of the engine compression, test it every 2000 miles or so.

:driving

[PGiljevic]

Another PTS horror story

Spoke with a customer last week who contact me out of desperation, his story as follows.

First engine build on PTS engine failed on initial rolling road dyno tune!
Engine taken out and sent to another "specialist" who put in new PTS along with all recommendations by Peter Glover (backyard maker of this sh&t product).

Engine literally drowned in degummed caster oil as per PTS instruction, and fuel mixed with 10% methanol to aid longevity. Made 585bhp @ 8500rpm on 20psi boost (reputable engine dyno), this is a road car that is street raced on ocassion. Now remember this is pretty low duty maximum power use in the scheme of things.

Exactly 2000km of road running the engine is trash again (very low compresion and the seals are f7cked AGAIN) and PTS simply say "they are NOT road suitable apex seals and we dont ever sell them as such!" and hang up the phone LOL.

These pieces of sh7t DO NOT LAST IN ROAD CARS at high power!!! I have seen this and been told it many times by people who are just sick and tired of constantly wasting time taking engines in and out, and then paying to repair something that should still be running. Its a false economy, you are actually paying a metric dick load more constantly fixing something that on stock Mazda apex seals would still be running :rollin

By comparison to this story (on soft backyard made seals), on my own stock std 13B-REW after 8000km+ of very hard consistent testing over 2 years my engine is still within 10% of its initial 1800km run in compression test That is well over 4 times the life! and its been tested on a much higher duty cycle (higher average time at full power) which is within 30bhp between both engines. < Though mine has much more "higher" mid range power so in fact is under more "load" than this one that can\'t make it past 2000km when used to any great extent even just as a road car.

As fully documented and posted here in my water injection thread > http://www.aquamist.co.uk/vbulletin/showthread.php?t=1590&page=14

[suba]

I shall certainly be keeping tabs on the engine - it\'s not a power monster, around 350-360 at the wheels at around a bar of boost on a To4E / S  :Thumbs-up