Compression test..

Started by kev_coupe, November 12, 2009, 01:39:45 PM

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kev_coupe

I\'m new to rx7\'s, been living over in the land of Honda\'s for the last 5 years or so!  Had a few nice cars over the years, my last one being a 396bhp Integra Type R Turbo.  But I feel its time to move onto another mark and ive decided an FD rx7 is going to be my next money pit!

I\'m going to see a car tonight which is not far from me and has supposedly been fitted with a new engine which has covered 37k miles but there is no evidence of this.  However, the chap selling the car has been kind enough to provide me with the results of a compression test on the engine

Front rotor - constant 7\'s
rear rotor - constant 6.5\'s

He also sent me accross some video\'s of the compression tests being carried out. From reasearch, I\'m aware this is not the most accurate method of checking compression levels in a rotary engine but its better than nothing!

You can have a look at the video\'s below...

http://s148.photobucket.com/albums/s1/kev_coupe/?action=view¤t=Front_xvid.flv

http://s148.photobucket.com/albums/s1/kev_coupe/?action=view¤t=Rear_xvid.flv


This is the car in question, and any observations would go down a treat!



I\'m looking for some advice on whether this is a good purchase or not for my 1st rx7.  I\'m fully aware of the high running costs of these cars and am under no illusions that it will run forever without a rebuild.  From past experience, the enthusiasts club is always a good place to start to look for advice and i have spent a lot of time online reading up on what to look out for.

I look forward to reading your replies!

Kev.

nuki

i believe a new built engine runs 8 Bar or very near to 8bar.
my friend had starting problems and his compression turned out to be 5bar.

kev_coupe

#2
Quote from: nuki;653785i believe a new built engine runs 8 Bar or very near to 8bar.
my friend had starting problems and his compression turned out to be 5bar.

Yeh i had read that when it drops to the 5 bar level that it can cause problems.  But ive also heard that as long as the compression is even on each rotor that they can still run fine even into high 5\'s.

Again, I dont claim to be an expert through what i\'ve read.  I\'d much rather take the word of people who have physical experience in working with rx7\'s :)

BlitzBoy

How much is the car up for dude?
"Piston Killa" 3rd Gen\'94 \'Oldone Racing Full Bridge Ported REW 13b engine with SCR seals\'. HKS T51 KAI turbo BBM mapped Motec ECU

JDS/HKS Street Class Championship Runner up 2011
Rotorstock winner 08,09
http://pistonkilla.blogspot.com/
old spec HB T51 470 @ wheels @ 1.2 BAR, 555 @ fly 10.46 @ 130 @ 1.25 Bar
new spec FB T51 482 @ wheels @ 1.15 BAR, 570 @ fly

New Project
"el fénix" RX2 by Mark & Mark

Nik da Greek

I\'m sure Jit will bend your ear shortly, but his usual mantra of "an FD is more than just an engine" bears examination. 15+ year old bushes, pillowballs, shocks, interior trim etc can all add up to kick you massively in the wallet, just like the engine can! If you\'re planning a stripped-out track beast, I guess you won\'t care, but if it\'s a road car, it\'s worth bearing in mind. Hard to tell from one solitary pic, but it looks pretty much bone stock. It may also be worth (depending) on price buying one that\'s had at least some of the mods already done that you\'d want to do yourself. Prices are such that modified examples can be not far removed from stockers. Only downside is you run the risk of inheriting someone else\'s badly-executed bodges. Compression tests also aren\'t nessecarily the be-all and end-all...does it start hot or cold? Does it hold idle? Is it mapped for any mods to intake or exhaust, or still on stock ECU? Does it have horrible water seal failure imminent from being stood laid up? etc, etc.

kev_coupe

Thanks for that mate.

The car is up for £3200.  Its got a years MOT, and 6 months tax.

Im taking a mate along to see it who is an experienced mechanic so he should be able to assist in general wear and tear items such as suspension components.  I\'d rather have a stock car to build on.  Ive spent a lot of money in the past trying to fix other peoples mistakes and i\'d rather start fromthe bottom and work my way up.  Already had a look through the parts for sale section on here and seen a few bits and pieces haha!!

I\'m aware that this is cheap for an FD and it might not get me the cleanest example but it seems like a good starting point if all goes well tonight.

Thanks againfor your reply nik!

Jit

Niks done the ear bending on my behalf so no need for me here!!!

kev_coupe

Quote from: Jit;653802Niks done the ear bending on my behalf so no need for me here!!!

I\'d have been worried if i didnt get anear bending!! Its good to know im in the right place :Thumbs-up

BlitzBoy

Silver is a good colour for stock FD, if I didnt have a black one I would go for silver they look so right in this colour.

Good price as well, as you are taking a mechanic Im sure he would look out for the obvious stuff in the body and drivetrain
"Piston Killa" 3rd Gen\'94 \'Oldone Racing Full Bridge Ported REW 13b engine with SCR seals\'. HKS T51 KAI turbo BBM mapped Motec ECU

JDS/HKS Street Class Championship Runner up 2011
Rotorstock winner 08,09
http://pistonkilla.blogspot.com/
old spec HB T51 470 @ wheels @ 1.2 BAR, 555 @ fly 10.46 @ 130 @ 1.25 Bar
new spec FB T51 482 @ wheels @ 1.15 BAR, 570 @ fly

New Project
"el fénix" RX2 by Mark & Mark

neil_jdmr

One thing to add mate is dont be put off if there is a but of mayo type gunk in the oil filler or you see a small amount of white smoke on cold start that clears up in the first few mins. These are both usual for fd\'s
Standard sequential, standard engine, Oem body, 1.2bar, WI

Twins retired. KKK K27 1.25bar courtesy of Jason and Stu

fil_auto

Pretty red honda dude on the Rega\'s!! ;)

Looks like a decent amount of car for the money with plenty of life left on those comp results! Once you\'ve had a good check-over with the mechanic and all is good ( which it pretty much should be! ) We\'ll see you back here very soon!

Njoy... and welcome to the club ;)

kev_coupe

Well this car turned out to be all i thought it was going to be!

Drove it home tonight and im over the moon with it.  Checked everything possible and spent a good bit of time looking over the car with my mechanic.

The paintwork is immaculate, bar a few scuffs on the front lip (which i think is par for the course) and the paint has flaked off the centre caps for some reason?

Such a different driving experience to the turbo teg... power delivery was manic on the integra but this is so much more progressive.  I love it!  

Going to spend tomorrow cleaning it up and ill get some new pics up at some point.

QuotePretty red honda dude on the Rega\'s!!
Thanks, that started life as a runabout, but ended up full on engine swap, respray etc....



This is the one i miss most



:(

I hope the rx7 has a similar future :)

lee mills

Congrats on your purchase enjoy:Thumbsup!

kev_coupe


Nik da Greek

Quote from: kev_coupe;653887Well this car turned out to be all i thought it was going to be!

The paintwork is immaculate, bar a few scuffs on the front lip (which i think is par for the course) and the paint has flaked off the centre caps for some reason?


Glad you\'re chuffed with it, dude....and they all do that, sir :rollin

you\'ve had a pretty awesome motor by the look of that \'Teg, think I remember that mag feature. I\'ll watch with interest to see how the Rex turns out :Thumbs-up.