Some more Dyno Results

[73GreenMachine]

Last week, the Cortina got strapped on the dyno for the third time in two months. Previous work showed a power of 102rwkw with fuel supply issues above 3800rpm. Given what has been done to the motor, I wanted to try another company, one more suited to LPG performance work. A brief rundown of the setup is:

250ci bored 20 thou over, blueprinted and balanced
200ci rods and ACL Race Series dished pistons (~9.8-10:1 compression)
282 degree Crow Cam
Yella Terra Roller Rockers with chrome moly rods (Thanks to Mike and Classic Inlines!)
Ported log head with oversized intake and exhaust valves
Nissan 65-70mm throttle body with Impco 225 mixer and L series converter
Custom 6 into 2 extractors with twin 2" exhaust system
Recurved Bosch XD Falcon distributor with vacuum (20 degrees initial advance 35 final)
Crane Hi-6 ignition system with Fireball Coil (the built in rev limiter is very useful)
Celica Steel Case 5 Speed gearbox with heavy duty clutch
Standard 2.92:1 open differential

With the above setup, the car made 123rwkw, still with some room for improvement due to fuel control issues and a mystery misfire that still isn't fixed. For some reason, this dyno run showed the mixture go rich as it approached the top end, in total contrast to the previous run. If anybody is interested I will post the dyno graphs.
I think 130rwkw would be possible with this setup, but do not wish to spend more time/money tuning it as I have a 2v head and am soon to acquire a gas research throttle body. I may even go the new aluminium head depending on exchange rates and the cost to rebuild the 2v, whichever is the more economic choice. I think this must be near the capability of the log head.
The aim with the next setup is to try and crack 160rwkw and hopefully the 13 second quarter mile that I have been chasing for the last few years!

 

[xy500]

thats awesome! i can't beleive you got so much power with the log!
i'd like to do some similar things with my 250, like running it on gas and all that, i'm glad to hear im not the only one running 20 deg initial, i thought i was crazy winding the dizzy that far!

do you know roughly how much money has gone into it excluding labour?
keep up the good work!

 

[73GreenMachine]

Yeah the timing is a weird issue but from all I have seen, LPG prefers more initial and less total timing that petrol. I had my car at about 12 degrees advanced on petrol so its not all that far out of reality.

As for money, if we don't count the few thousands wasted on failed engines.. you could probably build a motor like mine for around $4500 depending on how much you do yourself. I think the machine work, balancing, assembly etc was about $1600, plus another $500 for the head rebuild parts and assembly (I did the majority of the porting myself, my engine builder tidied it up) another thousand for pistons, harmonic balancer, flywheel, clutch setup etc, another thousand for roller rockers and the ignition box setup, plus at least $500 for tuning (finding a place that does proper work cost me at least another $500. Wow, thats a bit more than I thought I'd spent! Mind you, if you start with a 2V head, it would not add much to the total bill and you would have another 30-40rwkw, making a much more respectable motor for the money. The other option which I will pursue later is turbocharging the current setup after the 2V is done That should see me well over 200rwkw and maybe into the 11s, still as a street car.

I think a Cortina with ~160rwkw and a decent chassis setup could crack high 12s at the strip, for a car that owes me $13k over 6 years, thats not too bad. The other bonus is that when I'm not fanging it, it only costs $10 per 100km on the open road

 

[TCSTEVE]

Hey hey, nice work Brett.

Still gotta get together for that race.

My car will be ready late this year, money pending

AIR will be ready late this year too i hear......