SVX gravel rally car...surely not? Absolutely... - Page 14

TomsSVX · #**196** 05-27-2007, 11:49 AM

glad to hear she is running well again.... Good luck and keep at it

Tom

Crazy_pilot · #**197** 05-27-2007, 11:53 AM

Quote:

Originally Posted by dynomatt

And some photographic evidence...

YAHOOOOOOOOO!!!!!

RSVX · #**198** 05-27-2007, 02:17 PM

Quote:

Originally Posted by dynomatt

And some photographic evidence...

2008 Calendar stuff right there!

SSSVX · #**199** 05-27-2007, 11:58 PM

*subscribe*

you're a man who's the strong will.

enjoy your thread.

wish you succeed in the rally race.

subbieatnz · #**200** 05-28-2007, 06:19 AM

cool project

dynomatt · #**201** 05-29-2007, 02:51 PM

After a marathon few nights, the new engine is together and ready to fire up (fingers crossed).

Some interesting developments for people.

Compression is up from 10:1 to 11:1 (ish)...this was done by skimming the heads by 1mm. The intake manifold bolts on perfectly due to the slack from the two piece intake manifold system. The ports aren't perfectly lined up (weren't from the factory either), so there'd be room to match port the intake system if somebody was bored.

Also, the result of having the heads skimmed is that the base timing of the cams goes out of whack. 1mm each side means that the right bank of cams is retarded by about 7 degrees and the left bank (because it's at the end of the belt run) is about 11 degrees.

However, we redrilled the cam wheels in some different locations, and have now been able to reset it to about 2 degrees retarded each side.

I don't fully understand the implications of this...but that's why I surround myself with people who do!

Also, the belt and standard tensioner have survived this process unscathed.

Hoping to fire it up this morning, then off to the dyno...should have some positive or negative results later today!

Wish me luck!

Matt (typing with sore fingers)

Crazy_pilot · #**202** 05-29-2007, 03:01 PM

11:1? Cool!

Just remember, octane is your friend.

dynomatt · #**203** 05-29-2007, 10:43 PM

Yeah no worries...we're running 100 octane.

Back from the dyno. Results aren't that inspiring. Think it's being held up by the standard intake and exhaust headers now. My rules won't let me change them.

It made about 185hp...max power was limited to 6000rpm though...we were thinking it should rev to at least 7000rpm and still make power.

It feels strong though.

Interestingly, the IRIS didn't do much...we did two back to back power runs with the valve open and closed...then overlayed to see where it would benefit from switching it on, and it seemed that it's best with the valve closed all the time.

M

Trevor · #**204** 05-29-2007, 11:38 PM

Hi Matt, I have been watching your progress.

Are you saying that power falls off after 6,000 RPM, or that it is flat from there on?

I am not surprised regarding the IRIS experiments, I argued along those lines some time ago in respect of power output. It is affectively an economy device assisting the lower/mid range. For your application it is wothless.

You must fit a timing protractor and plot the opening and closing points on each cam relative to TDC, in order to see what is what. My bet is that it is here where you will find what is missing from the stable.

dynomatt · #**205** 05-30-2007, 03:30 AM

Trevor,

Power drops off after about 6000...weird. Should keep going I thought, but we think there's some power to be made from adjusting the cam timing more.

We're running about 2 degrees retard...wisdom suggests we might be able to shift the power curve up the line by retarding them to maybe 5 or 7 degrees.

Ignition timing hits a peak of about 36 degrees advance...strange when LAN talks about 45 degrees, unless that's something to do with the cams and the compression.

Trevor, as to a degree wheel, we had them. We have also redrilled the cam gears to give us significantly more adjustment.

It's not something we'll do before this event...tomorrow is reconnaissance, where we drive over the roads and make some pace notes...then Friday night the event starts.

Phew.

M

TomsSVX · #**206** 05-30-2007, 09:16 AM

Yeah, I am not shocked either... Takes a lot to make more power out of an N/A EG33... The cam profile is key and I need to ask if you upgraded the springs when you changed valves?? Either way... the exhaust is going to make a big difference as you are probobly restricted by it... The intake should not be a weak point as I am even still using it. Don't forget.... the intake cams run off of the exhaust cams as I am sure you know... Changing their timing will not benefit you much unless you change them from eachother(impossible except in 7* increments.) Good luck with the event and I hope you all do well

Tom

XT6Wagon · #**207** 05-31-2007, 12:43 AM

I wonder if its the hydraulic lifters colapsing. Certainly its an issue with some cars.

Certainly with the work being done on the cams and valves, one might assume a switch to either WRX shim under bucket or STi lash buckets would be a good idea to reduce valvetrain wieght and prevent colapse.

dynomatt · #**208** 05-31-2007, 05:45 AM

I'm running shim under bucket.

Matt

dynomatt · #**209** 06-01-2007, 04:36 AM

Bit dejected.

The car was involved in a road accident on its way to the start of the rally. I hurt my head when a guy behind me didn't stop at a crossing...I hit the roll cage.

Not sure what the odds are...I wasn't even competing...was on my way to the start.

Far out.

Guy hit me very hard up the back pushed me into the car in front...both ends damaged. Have the parts to fix, just no motivation (and a sore head).

Cut a guy a break?

M

XT6Wagon · #**210** 06-01-2007, 10:32 AM

hope you get to feeling better... and also uh, now you know why I tell people NOT to cage thier cars unless they plan to drive around with a helmet on all the time.

Can you ding his insurance for enough to pay yourself to fix it?

Anyway, get better and don't let it get you down.