Autocross prep 2013!

rado · Postby **rado** » February 9th, 2013, 4:52 pm

Had a taste of "Dex" last year ad it was 'more-ish' :lol:

So I decided to prep my car for the 2013 season and I started by addressing one weak point with my car that I've discovered so far.

Due to the high rpm I run and the slightly thinner cylinder liners due to my over sized pistons I've found head gasket sealing to be an issue. So my plan was to re-enforce the sleeves by an old school technique called posting or pinning the block.

Here are some pics of the process.

First find the approximate center line of each cylinder..

rado · Postby **rado** » February 9th, 2013, 4:57 pm

Then we decided how far down the block we would put the posts, and start the drilling!

I should mention that the post were cut from 3/8 threaded aluminium rod. Using the same material as the block would ensure expansions rates are uniform.

rado · Postby **rado** » February 9th, 2013, 5:00 pm

Now the holes have to be tapped with the appropriate cutter.

rado · Postby **rado** » February 9th, 2013, 5:08 pm

Finally just insert the pins and hand tighten snug with the sleeves. I used marine grade JB weld epoxy on the threads and over the installed plugs to seal it up. The JB weld is rated to 500 deg F which is way higher than the operating temps of any engine.

The net result is considerably stronger sleeves with no compromise to cooling efficiency. In conjunction with a correctly sized head gasket it marks the end of high RPM head sealing issues.

Here are a few pics of the final product.

whizpig · Postby **whizpig** » February 10th, 2013, 4:44 pm

So yuh back in the carpark this year?

but i doh understand how reinforcing the cylinders improves the head sealing, of course this stems from me not fully understanding why high rpm results in poor or insufficient head sealing, is it a vibration issue perhaps?

rado · Postby **rado** » February 10th, 2013, 6:04 pm

yup all tests are positive.

Since our engines have floating cylinder liners, there can be movement though small. Hi RPM just amplifies the situation.

I should also point out that my head gasket was the exact size of the cylinder bore. This is not the ideal case. There should be some relief between the HG and the chamber. For example the stock cylinder is 78mm and the stock HG is 79mm. This is a key factor also.

On a lighter note... I took on a turbo 1800 GSR box lancer yesterday..... runs real nice

rado · Postby **rado** » February 10th, 2013, 7:44 pm

So since I pulled the engine for the block enforcement I decided that I would change out the cams.

Check out the lift on these bad boys :shock:

chris1388 · Postby **chris1388** » February 11th, 2013, 1:25 am

Does it still idle normally rado?

rado · Postby **rado** » February 11th, 2013, 9:24 am

No Chris, it doesn't. I had to fab a throttle stop on the pedal to keep the idle at about 1050.
It was a known possibility although I was hoping to be able to tune it in. The LSA ( lobe separation angle) of the cams is smaller than stock and does not promote strong vacuum and good idle manners.
I have a few more options to try, so well see

chris1388 · Postby **chris1388** » February 11th, 2013, 2:20 pm

So does it just sound like a fast idle? Or is it erratic ?

Should be fun at dex trying to run that monster down with the ignis :twisted:

rado · Postby **rado** » February 11th, 2013, 3:43 pm

Well it's you I have to prepare for Chris

That ignis of yours is on rails in the corners! But if just sounds like a fast idle. Not eratic

But since I've moved to SS class I have 3 points to spend so we'll see how it goes

chris1388 · Postby **chris1388** » February 11th, 2013, 9:39 pm

How come you end up in SS? Aren't you ESP?

rado · Postby **rado** » February 14th, 2013, 8:47 am

Sorry Chris.... I was battling Dengue since last weekend. Just got too week so I was off line for a while.

Last year I started some chassis mods. While the rules allow for upper sway bars, adding or modifying lower ARBs cost me 2 points. That in conjunction with the 2 points from the brakes bumped me up in class.

My plan is to tune the power to weight ratio to be close to the limit for ESP, extract the best torque I can, then focus on other handling improvements.

I'll also be running the car on super right through... 8-)

rado · Postby **rado** » February 14th, 2013, 8:55 am

oh.. another note: since I did not share phase 3 of my build on this forum... from the cam pics above keen eyes should be able to pick up the shim less buckets I'm running.

chris1388 · Postby **chris1388** » February 15th, 2013, 12:48 am

Doing some suspension maintenance on the ignis first half of the year....power will remain same for now. In the second half of the year I'll look into extracting a bit more from the m15a. Still in 2 minds whether to remain in SS or go up to EP. I may not be a contender for either since I will miss many events....but it should be fun running down EP.

rado · Postby **rado** » February 20th, 2013, 3:36 am

chris1388 wrote:Doing some suspension maintenance on the ignis first half of the year....

Wow.. that Dengue fever not easy! Still not fully recovered!

Anyway.. I would also like to do some suspension work on the swift because quite frankly there are times when the day to day ride is just too harsh for me, yet I want a lower stance for DEX so some solutions must be found.

Anyway I still have a couple basic updates to complete to the exhaust system geared towards fine tuning the torque curve.

Gonna put these on soon.