Edge RMK 800 turbo

[Eli]

I changed the vent line to 6mm (1/4") pneumatic line,

What about the compression, should I lower it?
I run 98octane pump gas (I think it is equal to 93octane US standard)

You should check squish clearance with solder and cranking compression/elevation above sea level. Then check with the turbo gurus. It sounds like .060" to .070" squish is what's needed, but check with someone more knowledgeable to confirm.


Sent from my iPhone using Tapatalk

 

[Samikoo]

I haven´t actually turboed my sled yet, but as far as run-on is concerned, from what I´ve heard you could try pressurising your slides.

You know, run hoses on top of your carbs. Drilling the slides doesn´t always work.

 

[Ztiggi]

I took off the head and found some minor marks of detonation,
I decided to lower the compression a little,
current compression was 12.6:1 with a effective chamber of 35cc,
head chamber was 45.5cc

I decided to increase the head chamber to 53.6cc
wich I think should give me
effective chamber of 43.1cc, and 10.2:1 comp.

current squish was 0.06", increased it to 0.083"

I got a supprise after machining the second dome, some big bubbles in the casting appeared, I took the head from my spare engine, but there was the same story,
I ended up with two wrecked heads, so I had to make a new one.

 

[jskattum606]

That is awesome. I wish i had the access to a sweet machine shop like that. Good work. Cool stuff

 

[Ryanlilly]

Very nice work!

Now want to build me one for my 700 edge? Lol.

 

[Ztiggi]

It misfires and runs like crap with the low compression head,

maybe I have to go back to stock again and just run low boost,
that worked a lot better

any ideas why the low comp one won't run well?

 

[Boston Racing]

The compression shouldnt make it run like you describe at all. I would look hard at the fuel system if the sleds backfiring. Do your have a wideband 02 sensor?

 

[Ztiggi]

The compression shouldnt make it run like you describe at all. I would look hard at the fuel system if the sleds backfiring. Do your have a wideband 02 sensor?

No, I only got egt's.
the backfire is worst when touching the throttle at idle and low rpm,
I also saw got some fuel coming out of my pipe.

the backfire never happened with the stock head, just sluggish at low rmp's.

I thought of maybe the compression is too low to ignite the fuel?
I'll try to raise it again and see

 

[Boston Racing]

Or maybe your float isnt shutting the fuel off and its overflowing into the motor. I think you have another issue...other that compression.

 

[Boston Racing]

My motor is 11.3 to 1 and I run at 9000 to 13000 feet. Mine runs perfect. Our effective compression ratios should be about the same.

 

[Ztiggi]

ok maybe the low comp head will work with some tuning,
but i installed a OEM-style head so I got 12.6:1 again,
and gave it 7psi, it braked 183hp without the premium switch on.

egt's where only about 1150, (50/50 pumpgas/100LL)
next thing I start thinking of is my ignition, haven't even checked it,
how is you others ignition set?

 

[Boston Racing]

My timing is stock, however I did close the spark plug gap to .018.

 

[Ztiggi]

My timing is stock, however I did close the spark plug gap to .018.

ok, and what is stock?

 

[Boston Racing]

I think its 26 btdc

 

[Boston Racing]

I will check the manual when I get home

 

[Ztiggi]

I will check the manual when I get home

nevermind, I found the manual myself, 29deg BTDC @4000 with tps disconnected.

but how much pre-ignition can it handle?
and has anybody tried to use something like a oil/boost pressure probe to manipulate the tps signal and retard ignition when it gets boost?

 

[Ztiggi]

Update!

repaired the tunnel extension after flipover,
added redneck oil cooler (my turbo does not have water cooling)
new layout on exthaust, added silencer,
added integrated watercooled intercooler into charge box
added dump valve

hope the new smoother exthaust and the intercooler will give me at least another 17 ponnies, want to get over 200hp

 

[jear bear]

How's the turbo working out for u ?would u do it again ?what do u think your hp is runing at ? Thanks

 

[go high fast]

ttt

 

[Ztiggi]

Hi guys, have not noticed your activity here, I got tired of tuning, and never got happy with the throttle response, power was good.

Sold the sled and the turbo kit, and bought ac1000 now