Mild 488 Stroker Dyno Results

Finally finished my mild engine. It starts real easy. Has a gentle lump on idle at 850 RPM. It seems to make no difference with 95 Octane pump unleaded or 98 Octane. It didn't quite make as much power as I anticipated it might, based on what I had read on the forum and according to conservative info I entered into DD 2000. I was hoping for an extra 25 HP and 30 FtLbs Torque, but overall I achieved what I set out to do.

- I finally built a motor at long last after 15 years of being a "Gunna"(Aussie slang for Going to...).
- I used up all of my bits I bought many years ago, even though a lot of the stuff was out dated with better stuff available now.
- I could have built a much better motor using alloy heads and a Scat 521 stroker, but I really wanted to finish what I started all those years ago, even though it felt I was reinventing the wheel with the Chev-Rod Stroker (instead of buying something off the shelf).

Here's the Combo....

* D1VE 2-Bolt Block, 30 thou over bore.
* D3VE-A2A Heads (2.20/ 1.76 Manley SS Valves)
I tried to use the head porting tips as outlined in Scott Johnson's awesome site, but as the head porting had been started years ago by a mate of mine, it was hard to match certain parts. I purposely kept the intake on the smallish side to promote torque. For our first go, I'm happy with the exhaust flow, even though it's not as good as Scott's flow figures.

(at 28" H20)
Lift Intake Exhaust
.100 69.3 56.0
.200 141.7 107.0
.300 206.2 147.0
.400 256.4 171.5
.500 290.0 190.0
.600 305.4 195.9
.700 315.7 190.0

* Compression Ratio - 10.47:1
* Solid Flat Tappet : 253 /260 @50 with 0.616/ 0.636 Lift on 110 LSA
* Offenhauser Portosonic, single plane manifold.
* 850 Holley DP (I also tried my untuned 1050 Dominator that had been sitting around for 15 years, at the last minute, but it didn't like it). I really wanted to also try a 950 DP but couldn't find one to borrow and I already had the 850.
* Speed Pro Forged Dome Top Pistons L2443, milled to a flat top.
* Lunati Steel Rods 6.535 long with BBC mains (2.20). We offset ground the Crank to 4.030" but had to do a heap of extra machining for the Ford wrist pin and std piston pin height.
* MSD Electronic Distributor, Acel Coil, Eagle Leads.
* HV Oil Pump
* JP Timing Set.
* Restrictive Extractors (1-7/8 Tri Y's), as I did not think the combo warranted doing an RRS strut front end.

RESULTS:
Peak HP 494 HP at 5,600
Peak Tq 511 FtLbs at 4,600

Here's a link to some videos and pictures. The Running in video shows one of the engine mounts smoldering as it was touching the pipes. There's also a pic of the largest can of Vaseline (petroleum Jelly) I've ever seen.


http://s88.photobucket.com/albums/k162/billk460/?start=all


Overall, I'm happy with the result as I have a nice street motor, with more that enough power for a weekend street car. It should be a lot of fun to drive.

Many thanks to all that have helped me along the way. I have learned heaps with this motor.

All the Best

Bill.....

hey.its benny! ur gonna have alot of fun with that thing mate. what brand is that cam? you should of borrowed my 2'' spacer,people reckon their worth 10-30 hp on some engines!

COngratulations Bill!! The engine sounds great on the Dyno Run!! In what car are you installing it??

Nice build.

Sounds good, and my software calls you pretty close on the power and that is good as it means it is likely fairly close on my build. My software shows you down 400 rpms on peak hp and torque from what you would have with the 950. It shows up to another 20hp, but with less torque. I know that is not accurate but I would say its 915cfm call is probably right.

So you may have a few more hp there!

hey.its benny…. what brand is that cam? you should of borrowed my 2'' spacer …
It’s a custom grind based on my flow figures from Camtech in Sydney. The proprietor Malcolm is a real nice bloke to deal with.
In what car are you installing it??
Australian Ford Falcon (1971 XY). Here’s a pic…
http://i88.photobucket.com/albums/k162/billk460/Picture056-c.jpg
Nice build.
Thanks dfree383.
…. I know that is not accurate but I would say its 915cfm call is probably right.So you may have a few more hp there!
I think it would have liked the 950 DP, but I used what I had. DD2000 said it was only worth about 7 HP so I didn’t think it was worth selling the 850 for a 950.

Hi Bill, nice to hear you finally finished it. That should be a nice street motor, especially with over 500 ft.lbs of torque. I think you'll find even a 1" spacer under the carb will give a few more hp, as would a 950 carb, but it should drive fine with the 850.
I think a better set of pipes on the exhaust would definitely free up a few more hp, but that's the limitation we face with the small engine bays when cutting is not an option.
I look forward to hearing about how it drives, keep us updated.

Hi Bill, .... I think you'll find even a 1" spacer under the carb will give a few more hp, as would a 950 carb, but it should drive fine with the 850.......

Thanks for your kind words Todd. We did run a 1" - 4 hole spacer on the Dyno. I hope to use it in the car, assuming clearance under the shaker.

I did not kid myself about the pipes from the beginning. I knew what I was buying and knew their limitations but was not prepared to do the RRS front end with Iron heads.

All the best...

Well done Bill .Nothing wrong with those numbers for a pump fuel engine and for what your use is it will work nice.. I always said those pipes were ok for value but for the price i don't think you can go wrong with a little tidying.In an unmodified XY i don't think you'd gain a lot even with custom pipes with the engine bay limitations.

Man that motor sounds great ,you can really hear it grunt when the dyno hits but then it recovers nice and builds rpm ,way to go.........ROn

Nice writeup BillK with lots of good details. That's EXACTLY what this section of the forum is for. :D Nice motor too!! :twisted:

I think you should be pleased with your results. I like the pictures of the glowing headers, the engine is not high compression and that causes it to make a lot of EGT. I think it would have been very interesting to have tried a 4 into 1 header as a comparo to the try Y setup.

[great stuff when is it going into the vehicle mate

Nice writeup BillK with lots of good details. That's EXACTLY what this section of the forum is for. :D Nice motor too!! :twisted:

Thanks cletus66, I hope somebody can learn something from the info I have posted, as I have learn't heaps from you guys.

...... I think it would have been very interesting to have tried a 4 into 1 header as a comparo to the try Y setup.

Thanks Dave, I tried to get my hands on a good set but it didn't eventuate. It would have been interesting information, though. I was also going to use a set of factory manifolds out of a mustang, I think, to see how this compared on the Dyno. I ran out of time and had to travel a fair distance to pick these up.

[great stuff when is it going into the vehicle mate

I have pulled out the 351 clevo and hope to install the 460 over the Xmas break.


All the best

how is it going fingers crossed for you mate

...the engine is not high compression and that causes it to make a lot of EGT.

That means there's wasted fuel (fuel=hp) going out of the exhaust...

hows it going bill

do you have any audio clips of it at idle?

do you have any audio clips of it at idle?

Hi Guys,

I haven't logged on for some time. I have been real busy over the last few months with business matters.

I finally installed the motor on Valantine's day (14th Feb- The wife wasn't really happy about the day I chose, but it was the only day a mate of mine was available to help me with it).

The car sat there for ages waiting for me to find some time to finish all the fiddly bits like, fuel lines, fuel pump, new radiator, sorting out the linkages, electricals, installing the shifter for the C6, finding a longer speedo cable etc... etc... etc.

I finally got it finished last week, but found a few teething problems. There is a small oil leak with the C6, which I am getting fixed this week. I also have to sort out some issues with the cooling system and some more electrical work.

I have only driven the car for half an hour due to the teething problems. But the twin 3" exhaust sound great (although a little louder than I expected for a mild motor). The 2500 stall converter I chose feels great and works well with the engine's torque curve. The new 235/60x14 Kuhmos I put on the car 2 years ago are too easily turned with the torque of this motor. I can't wait to till the day when I have used these up so I can get some real tyres under the old girl.

Once the car is returned back to me I will take some video and put it on the net.

Cheers... Bill.

hey mate,good stuff! bring it round to the shop so we can have a look! can you fit the original engine fan+shroud,that always fixes the over heating problem! have plenty of fun with it anyways!

Hi Bill,
Good to hear the progress on the car .

Theo

good stuff

pretty nice motor and dyno vid.....

Hi Bill,

Good to hear progress is being made. Keep us updated.

Cheers,

Todd

...the engine is not high compression and that causes it to make a lot of EGT. That means there's wasted fuel (fuel=hp) going out of the exhaust... Exactly, the fuel is still burning in the header pipe.

Good job on the engine build! Only two things I would have done different (if you don't mind me saying):
An Edelbrock Performer RPM 'Air-Gap' (dual plane) intake manifold would provide more power on a -5600 RPM engine.
Better flowing cylinder heads (maybe smaller combustion chambers too) would be better suited for a camshaft that size.

But...it doesn't matter because you have more torque than your tires can handle! Cool!

do you have any audio clips of it at idle?

I finally got a chance to take some video on Idle "MauriSSSio". It sounds better in real than on the video, but you get the idea.

The 351 cleveland sounded real nice, too. This motor sounds more free flowing with the twin 3" pipes.

I sorted out the cooling system. I'm running 4 small thermo fans with a four core radiator. It sits on just over 180 degrees (just over half way on the temp guage) which is cooler than the clevo ran.

The C6 auto caused me some grief with oil leaks, but these are sorted now.

The only problem now is that my brakes aren't as good as they used to be. It may be due to vacuum issues or maybe the booster diaphram needs replacing. I need to get a brakes guy to look at it soon as it's a little scary when your brakes aren't 100%.

The 235/60x 14 tyres are useless with the torque this motor is putting out. It just fries these tyres off the line. I can not wait till I get some real tyres under the XY.

http://s88.photobucket.com/albums/k162/billk460/?action=view&current=XYonIdle11-Jun-07.flv


Thanks for all your help guys.


Cheers Bill....

sounds nice

bump