Jay Jays Mk2 Project

[Bug_racer]

hahaha, well i dunno. the pinging gets pretty intenese.

mm, i have no doubt the engine will out last the car...

Pinging will have very little to do with cam timing .

I re-read the whole thread . There is no concrete data for the engine ???

Pistons have been flycut and its running a 288 cam . Thats it ????

If your gonna build a high comp engine your gonna have all the data on file , otherwise its a time bomb so:

Whats the deck height with the piston at tdc ?
head gasket thickness?
Head CC ?
CFM flow of inlet/exhaust ports , what valve size , spring size ?
Is this the cam : http://www.mk3love.com/reviews/engin...ulic-camshaft/
and lastly whats the AFR on WOT ?

[jayjay]

ok ok ok . i have no concreted data for this motor. it's going to explode.

wtf are you going to do with those numbers? tell me the exact theoretical horsepower and the exact motor characteristics? how about i cut the block in half so you can do a metallurgical analysis.

/thread.

[esevwbits]

Sounds like bug racer is just trying to avoid you blowing up a wholehearted project!
And its also good knowledge to know whats under your hood at the end of the day!

keep away from e10 haha!

[Preen59]

I would actually suggest running E10 if you can get some good stuff. Ethanol burns slower and cooler than petrol and can slow and control your flame speed and lower combustion temps.

ok ok ok . i have no concreted data for this motor. it's going to explode.

wtf are you going to do with those numbers? tell me the exact theoretical horsepower and the exact motor characteristics? how about i cut the block in half so you can do a metallurgical analysis.

/thread.

More cam duration and overlap equals more cooling of the combustion chamber and also lowers your dynamic comp ratio. So you can run more comp the bigger the cam you run.. Basically

AFR he wants to know because a lean condition can cause an overheated combustion chamber/ piston crown and cause detonation (pinging).

Deck height determines how tight your squish is. Too tight of a squish can cause detonation on the edge of the bowl.


The *Ping* sound you hear when detonation occurs is 2 separate flame fronts crashing into eachother, causing a shock. One flame front is from a detonation point, the other the spark plug.

Detonation can do anything from burn pistons to crack rods. If it's pinging its brain out.. Don't drive the bloody thing until you get it sorted.

[Yevvy]

jayjay took me for a drive a couple of days ago...and that thing is insane!!! he didn't take past 5 yet, but even then i was holding onto the seat ****ting myself haha i reckon after a good tune it will easily rip my bora

[evorobin]

Play with the cam gear to findout where you want the power band then get it on the rollers to sort the timing/fuelling

[Golf Loon]

Kjet is the devils spawn, especially when coupled with ratty wiring of an aged, messed with Mk2.

Thats all I`m saying.

[Golf Loon]

Today involved an expensive KJet Fuel Pump Relay and a quick road tune.

No more Pinging and a good basic setting. Woooooah is all I can say.

I`m sure Jay will chime in with some input.

[Jmac]

What was the go with the relay?????? Kjet is the bomb when its right, and BAD when its bad i personally like it. Really keen to hear the diagnosis on the relay though.
Good to hear the pinging is gone
Jmac

[Golf Loon]

The car never had a relay, just lots of spliced wires from a sucession of owners.

Beau built a new loom for the fuel pump relay and then was let down by all the relays being broken and overheating.

New relay $75! And bingo car starts and pump is controlled by relay again.

Quick road tune by me and its a bit of a beast