Don Terrill’s Speed-Talk

Just finished up & dyno'd this one, me & the various incarnations of this motor have a long history. It belongs to a good friend of mine who runs an LX torana hatch (google it - aussie holden with a long competition history in road racing) at hillclimbs & the occasional circuit sprint.

The 1st time I built this was in 04, last build was in 2010, this build has been a while coming!

From the outset it was never going to be a massive HP engine, years ago we chose to stick with the original design 'red' head castings to keep the car true to it's heritage.
Now that's a big stumbling block, the factory heads have 1.74/1.47" valves & MCSA around 1.65-1.7" - if you're thinking SBC type stuff think along the lines of whatever dinky little heads they put on 283's.

Anyways, the previous engine (& car & driver) held a few lap records at various tracks in southern Australia, it was due for a freshen & the car had been developed to the point where it could handle more power, add in that the competition had not been sitting idle & a few of the records it held were lost or getting close to lost.
It was time for a rebuild & more power.

Last time around it was making about 490hp & 440ft/lbs with a flat tappet cam (248/253 on 109 centres), pump fuel, dual plane intake & 750 carb.

Teardown showed up a crack in the old crank, so we had to switch it for a stupid $ billet steel job.

Current spec list is:

365 cubes (4.03" bore, 3.58" stroke - bang on the 6 litre limit for circuit racing engines)

1970's 308 'red motor' block - short grout fill, converted to 1/2" main studs, oiling system completely reworked with a priority mains oiling conversion + lots of other stuff
Billet steel crank 3.58" stroke & SJ chev pins.
Scat Q-lite 6" SJ rods
SRP pistons
Rollmaster timing kit
Powerbond steel balancer
Alloy flywheel

'HQ' red motor head castings with 2.02 & 1.625" ferrea valves, somewhere between 50-70 hours of grinder time in them spaced over 3x builds, I will never, ever do another set of heads like these. Machined for screw in studs & guide plates, 1.55" dia springs etc.
Crane rockers, pushrods & solid roller lifters
Crane custom grind SR cam - 262/266 on 108 centres, .438/.400" lobe lift, 1.65 rocker ratio for a tad over .700" valve lift on the intake.

TP single plane intake manifold with a 1" spacer attatched to the carb pad & ported into the runner entries, whole thing ported right through (I hate porting intakes)
QF 850 E85 carb with road race floats & jet extensions
MSD pro billet distributor
Crane Hi6 ignition

ASR dry sump pan
Peterson R4 4 stage dry sump pump
A mate of mine made the pump mount
Peterson spline drive hub for a SBF 4 bolt modified to fit the holden balancer
Peterson 4 gallon tank

12.8:1 compression on E85

Headers are 1 3/4" primary tri-y pacemaker's with 1 7/8" secondaries & 2.5" collectors - less than ideal you'd think, but the dyno reckons they're alright! - not that there is much choice, short of custom pipes they are the biggest pipes you can buy for a red headed torana.

After some trials with broken valve springs (broke 6x springs during bed in at under 3000rpm - dud heat treat I suspect) & 1 head springing a leak from some porosity (fixed with a hole drilled in the top of the head, application of JB weld & a screw in plug for the hole I drilled) we finally got it dialled in on the dyno today.

Grins all round, the 40 year old iron heads grudgingly let it make 556hp @ 6600rpm & 498ft/lbs at 5100rpm.

That may not seam like a lot for a 365 cube engine stuffed full of good bits, but given the limitations of the head castings it's a very, very good result! - going back a few years it was considered a tall order to get 500hp from these heads, the highest HP drag race engine I know off using these heads made 575hp with 383 cubes, methanol & a cam into the 270's duration, so you could say I'm pretty happy with our results.

Great stuff, Tony. I really like these type of builds vs the 'throw the lot' at it. A lot of those builds (and looking under the hood at the drag strip) are really formulaic. Stuff like this requires a little more thought and ingenuity.

Two things:

Why the wide lobe spacing? I feel like an engine like that would like something in the 105-106 range. Engines with similar specs and power peaks as that we play with are in the 104-106 range.

Headers are 1 3/4" primary tri-y pacemaker's with 1 7/8" secondaries & 2.5" collectors - less than ideal you'd think, but the dyno reckons they're alright! - not that there is much choice, short of custom pipes they are the biggest pipes you can buy for a red headed torana.

Why do you feel that is wrong?

I've shared it a bunch of times, but Elston is using 1.63 X 8" > 1.75 x 10" > (secondary) 2" x 12"-14", 2.25" choke, 3" collector merging into a single 3" tailpipe. Those engines are up about 50hp from where you are, and while they are 310ci, they're spinning to 8k.

Ford Boss 302:
https://www.youtube.com/watch?v=Da86jFdz8pw

Camaro from the same shop:
https://www.youtube.com/watch?v=HH8IPGwOLMg


Interesting to hear the slightly different exhaust pitch, despite being built under the same rules, same builder, and same exhaust configurations.

The headers are just off the shelf mass production stuff, no nice merges or anything like that, lengths were far from optimal & collectors seemed too small.
But it would seem primary pipe size is the main thing to look at, both sets of pipes we tried had 1.75" primaries but were very different in design - the 4-1's wont fit in the car so they were never an option, but we wanted to see how much we were loosing with the run of the mill tri-y pipes so the owner could decide on the priority of doing some custom pipes for it.
Not gonna bother with the custom pipes, not enough left on the table to be worth the expense.

Vid & pics of engine & car on facebook for those that have it:

https://www.facebook.com/10000603382717 ... =3&theater

that internal plumbing looks similar to what is used in a AMC trans am road race engine.

tony,
very impressive numbers
yes people will say it has a bit of compression,drysump oil system etc but unless people understand the red motor cylinder head casting and the work you put in
i see you really like crane cam and valvetrain that is very cool
i have not used crane for 20 years and i dont even know who bought them out but they must have there game on
i appriciate the reply for victor jrn intake you put up the other week,great information,not many people will spell it out like that

i have one question regarding porting intakes
when you are porting an intake for max performance do you measure the CSA at the plenum and MCSA at the cylinder head and try to keep the taper in the intake tract the same percentage throughout the intake runner
i remember you saying to open the top of the runner plenum opening at the top as much as possible where applicable
do you flow the cylinder head with intake bolted on and do you try and get each intake runner to flow the same cfm and velocity even though most cast intake runners are
different length?
any tricks of the trade appriciated
steve c

Nice work mate. Awesome numbers from the old red !

Steve - I don't tend to follow the trends of flowing intake manifolds, that can lead you down the rabbit hole & point you to larger runners that ideal trying to equalise flow between runners, with a single 4 barrel intake you are never going to see equal flow on all runners, don't try.
I concentrate on CSA's & taper, if you pick a manifold suitable for the purpose then the manufacturer (assuming them know what they're doing) will have got it pretty close, the job of the porter is to tweak it to suit the specific application, usually minor adjustments & refining of areas that are compromised due to casting & mass production limitations.
If you get the runner entry CSA's & shape right, the taper around the mark & the port matching right then let flow fall where it may, a correctly sized manifold will make more average HP than one that flows the best on the bench.

*IF* I flow a manifold bolted up to a head it's to check stability & velocity profile - to see what the runner is influencing in the head, but not to see what it flows in raw CFM.

I'll be honest here, I don't often flow manifolds on heads, I just make them what I consider to be the right proportions & leave it at that.
The TP intake on this has not been near a flow bench.

On the Crane stuff - Crane have been supplying stuff for holdens since the 70's, I don't think there is another company with a wider inventory or more experience with valve train stuff for holdens, if you build a lot of holdens you'll be using Crane gear!

To give an idea of the porting required on the heads:

Stock heads have a port volume around 90cc, these are a bit over 160cc, stock heads flow around 170-180cfm, these flow a bit over 260cfm.
All that metal came out by hand, very carefully as the ports are getting thin & a wrong move ends in a sprinkler.

In comparison mate, what sort of results are you getting out of the VN/efi Heads ?

If I built a motor exactly the same but with well ported VN's it'd make 650hp @ 7300-7400rpm & similar TQ.

KnightEngines wrote:If I built a motor exactly the same but with well ported VN's it'd make 650hp @ 7300-7400rpm & similar TQ.

Pity you cant get away with just painting the VN's red!

Australian Hillclimb championship winner in sports sedan 3001cc-6000cc on the weekend just gone.

LS? - never heard of her.....

Fantastic ! Great work mate.

How much difference is there between the Holden engines and a Gen 1 Chevrolet sb?
I watch touring car masters, what engines do the Holdens there run?

Erland