xcabbi is on the money.

The DOHC head far outflows a SOHC head.

VCT is overrated.

What does the DOHC head flow?

I cant tell you the numbers exactly but What do you get when you pump between 4 and 6 pounds of boost through a stock unported SOHC head. Now pump the same boost throught the DOHC head (standard XR6T boost) and see what you get.

Also there are a few of guys round here pumping between 20 and 25 psi through their SOHC motors and they are only getting 300-350kw at the rears. These guys are running decently sized camshafts as well and ported heads. Nizpro made 1000hp with only 23psi on the DOHC. The only mods were camshafts and valve springs. The head castings were supposedly left stock. Even when you factor in drivetrain losses of 25-30% that is still a big advantage over the SOHC. If you could somehow mate the DOHC head to the old block then that would be the cheapest road to horsepower but it all depends on how easy it is to relocate the oil pump.

Yep that is what my opinion is based on as well.

My AU made 308rwkw on 14psi, had an XR head, headwork and a custom cam.

A stock XR6 turbo with no head or cam work will more power on 10psi.

They also boost a lot earlier, rev cleaner and have s**t of aftermarket support.

I dont know another engine where you can go to a shop and buy a brand new bottom end fitted with forgies and billet rods for a reasonable price.

Dont think you can reason it with that logic as there are way to many other variables at play. The heads can only really be directly compared on a flow bench.

The DOHC will undoubtedly flow more, would be good to know HOW much more. For example, a SOHC head will flow about 300HP on the bench but when modified will flow upto 400 (and beyond with very aggressive porting). Would be interesting to know how the modified SOHC heads stood up to the DOHC's.

Seen a few interesting points come up in this thread.

Some of the points i'd like to add to:

Sump: yep it can be modded. I will have my BA sump off by the weekend and will have pics before during and after welding. I imagine that part of that hump is not only due to the oil pump but also due to the motronic wheel/hall effect residing behind the timing case (on an AU its on the balancer). It could also be possible to use a modified E-series sump. Guess it just depends if you prefer working with alloy or tin. I intend to do a "High-Energy" style pan.

VCT: i intend to leave disconnected at the moment. I have been informed of some of the principles of operation by Simon Gishus (via Nizpro forums). They are reproduced in Dan's thread (BA into EA). Apparently they can be moved in 1 deg increments up to 30 degrees. The problem being the signal required to operate the solenoids. As Xcabbi and Dan said they just move along the rpm point at which they make their power. If my V8 experience is anything to go by a 2 degree movement is roughly equivalent to a 500rpm shift in power/torque. Hence it is possible to lock out the cams at the optimum range for your combo. In the long run i wouldn't necessarily retain the stock cams anyway. A custom grind could sort that out.

ENG MANAGEMENT: I'll be running Haltech IG5 ignition only, waste spark 3 channel ignitor. No EFI...mine will be Gas Research like every other car i've owned in the past 6 years. I've been tipped that an Autronic could do the job in place of a MoTeC.

COILS:
Coil on plug.
VISTEON
3R2U - 12A366 - AA
FI1TA 3238CA

http://www.visteon.com/products/auto...lug_spec.shtml

I guess my big question is can it be paired up for waste spark or will this kill it? Coil pack is possible but routing the leads could get messy. I want factory appearance.

Photos will be taken in due course.

And the BA motor wont fit under an EA-ED bonnet on stock engine mounts

hmmm i like this discussion actually bringing up some meaningful stuff which is a first for this forum.

the DOHC head is interesting, as there was a company that made them for earlier modeles and the BA, i was under the impression that they did not make much more power.

i think maybe the BA motor is only worth looking at for an earlier falcon install if your going to turbo and chase big power.

i would like to see some flow figures from a standard ba head

yeah the e-series DOHC head were apparently getting around 125 rwkw running the equivalent cam profiles to the SOHC.

There was an e-series DOHC? That would have been nice in the EL.

Okay after reading some is it worth getting the VCT to run or let the motor run without VCT for a while until someone has figured it out?

phong =P~

There was a company that was making aftermarket heads. They did them for the 202 holden 6's, the 250 falcons and the 4.0's from memory.

Since gone out of business. I have never seen or heard of anyone who has one.

Krogdahl was their name IIRC.

Its good to see that people are starting to get into this DOHC engine convo and talk about what seriously needs to be done instead of knocking the s**t out of it, this is turning into a good read.

Not sure if this well help.. read a little of it.

http://www.performanceforums.com/forums ... t=67181670

funny when i started the looking into the conversion a year ago people thought i was mad. now that ive started everyone is into it lol.

p.s. a WOLF V5 WILL run the motor, and duel vct, and seq spark ect.