went to the dyno tonight

parish8 · 12-03-2007, 07:14 PM

stock 944 with 140k on it. 80psi compresion on number 3 cylinder.

mustang dyno. got 114rwhp and 117rwtq. convert that to dynojet numbers and that would be around 130rwhp wich i guess is right about where it should be.

tq was very flat. right around 110ft/lbs from 2500 to 6000rpm. a/f ratio was mid 12's wich seems a little rich. low compresion on number 3 didn't seem to hurt anything.

next is puting a emspro(fancy megasquirt) and spending some time on the dyno to see if there is any room for improvement. we are going to do 4 coils and not use the distributor. it might seem odd that i am messing with it but that just how i am and most of the stuff is free or very cheap. dyno time is free, emspro is free , wideband with dash gauge was less than 1/2 price. coil packs are a junkyard item.

probably have to put a turbo on this thing before long. i have to say i really like driving the car. i like the sound of it at wot. i like the way it squats when you get on it. i like the way it is just flat around any corner. now just double the hp and get some better tires under it and it will be even more fun.

just got my 3rd box of junk from pelican. i am geting all kinds off little stuff catching the car up on maintainace. pelican seems to be a good company to deal with. thanks for the forums!

jkrustchinsky · 12-03-2007, 07:19 PM

yes, ive put my megasquirt on pre order till i get my las few $$ for it, should be fun to do together. Josh

924Sman · 12-04-2007, 04:33 AM

80 psi on #3.......I would be ripping the engine apart. Valve/spring issue or HG is compromised. The inner springs on this model are known to break and after 20 yrs sure to be weak at the least. All the upgrades will be worthless until the engine is up to spec/fresh. May even do more harm if something internal is not spec.

Dal

phoenix_iii · 12-04-2007, 10:37 AM

Quote:

Originally Posted by 924Sman

80 psi on #3.......I would be ripping the engine apart. Valve/spring issue or HG is compromised. The inner springs on this model are known to break and after 20 yrs sure to be weak at the least. All the upgrades will be worthless until the engine is up to spec/fresh. May even do more harm if something internal is not spec. .

Dal

. .

JoshB · 12-04-2007, 01:23 PM

Hmm - for the low prices that the turbo's are pulling you would be better off buying one of those to start with. You'll get a strengthened transmission, bigger brakes, better suspension, more areodynamic front end, sides and rear underspoiler. Lot easier to upgrade the turbo when all the plumbing is already in place - of course the lower compression is handy as well unless you could get some of your other springs to break so you were an even 80 across the board

parish8 · 12-04-2007, 02:40 PM

i am prety sure the compresion is going past the rings. not the valves. doesn't sound like and easy or cheap fix and doesn't seem to effect wot power. i will fix it when it no longer runs.

as far as slaping a turbo on it. it's what i do, just let me do it.

nynor · 12-04-2007, 03:13 PM

um... i just read your signature line. apparently adding turbos IS what you do. any ideas on how to make our 951's TWIN turbos? now, that would be cool!

parish8 · 12-04-2007, 03:20 PM

Quote:

Originally Posted by nynor

um... i just read your signature line. apparently adding turbos IS what you do. any ideas on how to make our 951's TWIN turbos? now, that would be cool!

what exactly is a 95 and why would it need twins? i like twins on a v8 because of the layout. a really big single gets hard to manage when you need a 6" airfilter and a 5" down pipe.

924Sman · 12-04-2007, 03:20 PM

Blue smoke out the exhaust?

951 not 95.........model # of the 944 Turbo.
Dal

parish8 · 12-04-2007, 03:23 PM

Quote:

Originally Posted by 924Sman

Blue smoke out the exhaust?

Dal

no smoke at all. i took number 3 to tdc and put 50psi to it and there was a large amount of air coming out the crankcase breather to the airfilter box. none back out of the throttle body and none i could hear or feel out the tail pipe. if it could be something other than in the short block i would love to hear about it. i suppose it could be a head gasket but that doesn't seem as likely as a messed up cylinder wall.

tell me more about these springs. it is fine now but if i boost it the valve springs will become more important. how much is a new set?

924Sman · 12-04-2007, 03:29 PM

Turbo springs are 17 bucks ea.apprx.......944 na are 3x that much, very pricey springs. No blue smoke then I rather doubt the rings are bad and the rings are pretty stout anyway.

Dal

parish8 · 12-04-2007, 03:39 PM

Quote:

Originally Posted by 924Sman

Turbo springs are 17 bucks ea.apprx.......944 na are 3x that much, very pricey springs. No blue smoke then I rather doubt the rings are bad and the rings are pretty stout anyway.

Dal

17x8? thats not too bad, i will have to get a set.

no expert on this one but couldn't you have a bad compresion ring but a good oil ring. you do bring up a good point, if the cylinder wall was all coroded like some pic's i have seen it would likely smoke.

swaping springs is probably easier with the head off the car. i might just get one of those better head gaskets, get in there and do that and the springs in one shot. it would be sweet if it was something simple like the head gasket.

924Sman · 12-04-2007, 05:16 PM

Well let me say that in most cases blue smoke happens but not concrete. My thing is start small then move on. Cost being the major reason. Now having said that the rings require a complete tear down and not a fun one at that, just dealing with the clutch is a major PITA, then getting the speed sensors back to spec is another difficult issue, unless you get lucky and don't crack the bracket or damage the sensors etc. So doing the rings will be the time rod/main bearings should be replaced....mo money/time. Then all the seals/gaskets too. Then re ringing creates the need for cylinder machining, you should never replace rings in an old bore. I will stop here.

You need to do a cylinder leakdown test to help diagnose the rings first then if the need is there by all means tear it down. The HG can produce the loss of compression yet still not have any signs it has blown as in white smoke. This I can say from experience, I thought I took out valves when my timing jumped but not to be so it was the HG that was inches away from going all bad and blowing white smoke. I spent a ransom on my head then find it only had 2 cracked inner springs and a major pit in the head mating surface. Same loss of compression in 2 cylinders, 2&3 in my case. And without doubt a OE head is going to have a lot of carbon build up, this is why you will see post after post on stuff used to help reduce carbon, very common. This carbon can and does effect the valves seating capabilities and corrode the valve grinds.

Now for springs, a word of caution, however minimal, the turbo springs are stiffer and can cause the cam lobes to wear prematurely and cause some valve floatation in specific RPM ranges, again not good for a street use car, racing is another animal as it is running at hi r's and the floatation is negated or minimized. This is not to say the street version cannot run them and many do. It's still ok but there is some slight risk. Replacing springs should be all of them not just the broken ones, reason is they are old and lost some of the spring rate and one good one in spec and the other 20 y.o. is not, so now you have created a spring rate mismatch, even to all small degree. There a 2 springs per valve X 8=16 springs not eight. 8 inners and 8 outers. So double your cost. You will want/need to remove the head to remove them or take a risk going blind by a spring launching upon releasing pressure. New stem seals but the retainers are not usually replaced unless needed. Guides may as well be done too, they take the most wear and do wear out.

Here is a thought for you, my head has more money in it than my car is worth! But then I have some shiney metal little tidbits in mine.

Get a leakdown then report back.

Best of luck!

Dal