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After 4 years in the garage, my Dune Buggy is back on the road.

Now I want more power. I am using Dynomation 6, same as Mark and have learned quite a lot about what is going to work. I have a graph for the stock engine and then one for the build I want.

The stock numbers are with the carb and header set up I have now. 84 HP
The 2257 is with ported stock heads, bigger valves, stroked and bored with a nice solid lifter cam. 169 HP

That should make make a 1250 lb buggy move really well.

I am going to put up a thread for the chassis rebuild over the last four years too, look for that.

_________________
Wade Williams
Master Ferrari Tech
Restoration Tech
Engine Machinist
Fabricator
Racecar Driver

Well that's a nice improvement!

So the plan is drive it as is while you collect all the parts and then when winter returns rip it apart and double the hp right?

That is correct. I am planning to order the rebuild kit next week. It comes with crank, rods, pistons & rings, sleeves, gaskets & seals, and a new flywheel.
I am then ordering valves, seats, & guides. I will then start next winter with head work. I will install new seats & guides and start the port work.

_________________
Wade Williams
Master Ferrari Tech
Restoration Tech
Engine Machinist
Fabricator
Racecar Driver

So, I ordered the short block parts on Friday. 2257 cc upgrade. Stroker crank (78 vs 71), H beam rods, JE forged bigger bore pistons (96 vs 94), jugs, bearings, gasket set, & flywheel. Cam, lifters, springs, retainers, keepers, oil pump w/ cover, & cam gear set.
I need to order some valves and guides. Then decide on what seats I need. I can buy bare aftermarket heads, no seats or guides. If I am replacing all that anyway, why not get new ones? Decisions decisions.

_________________
Wade Williams
Master Ferrari Tech
Restoration Tech
Engine Machinist
Fabricator
Racecar Driver

Oooooh...pretty parts

Do the aftermarket heads have the corrected spark plug location? Anything else improved like the ports so they would save you a tom of work and may make them worth the money? Or are they cheap enough that its just worth having them so you can prep everything ahead of time and and basically have a tear down and rebuild weekend when the day arrives vs torn down for months waiting on heads?

The bare heads they have in stock have the Type 4 plug location, so I would have to relocate the spark plug to get the 914 position. Not a huge deal.
Also, the guide hole for the exhaust are bigger and would require a special guide with a bigger OD and 8mm ID. All of the performance valves are 8mm as they should be. Again, not a big deal. I believe they have a better potential for porting than the original casting & its new metal.
Still undecided on $700 in castings or not.

_________________
Wade Williams
Master Ferrari Tech
Restoration Tech
Engine Machinist
Fabricator
Racecar Driver

$700 is a lot of money for something you don't actually NEED.

Can you sell the old heads after you install the new ones?

Maybe I can sell them. I am not sure who would want them at this point.
I am trying to talk on the phone to the rep and see if they are improved in the ways of port shape and combustion chamber or if they are just duplicates.

_________________
Wade Williams
Master Ferrari Tech
Restoration Tech
Engine Machinist
Fabricator
Racecar Driver

Well, they made me a deal on the heads so I said yes. Not sure when I'll have them but you and I will need to collaborate on the seat and guide work. I may have to send them to you for flow testing as well.
Or I might try and convert my flow compare devise to a flow bench. I haven't studied the flow bench design enough to know what I need to do to make mine a flow bench yet. We will see as we go along. Always something I guess. It really is never finished is it?

_________________
Wade Williams
Master Ferrari Tech
Restoration Tech
Engine Machinist
Fabricator
Racecar Driver

I figured when you started asking about welding rod the choice to buy heads was already made

I use a simple formula for seats given to me by another buddy...seat ID=0.86 x valve OD then try to make the seat the choke point in the port and the port tapers out at about 2 degrees included angle. Do that and it will always work well form what I can tell.

There are other ways to do it that work. The US car guy talk about bowl volume and such and I can't argue that it seems to work....but I'm pretty sure putting peak velocity as close to the cylinder as possible works better.


You need about 3cfm @10" or 5cfm@28" per hp you want to make. that gives you a flow target.

Then a good port will do right about 190ft/s velocity at 10" (328@28) really good ports hit 200, DO NOT accept a number below 180. This gives you the seat ID you need, from that you get the valve.

That's how I do it. You already kind of know what valves you are going to use, so go the other way around in the math and out will pop all the dimensions and the hp.

Edit: again, this is nothing I developed, a buddy who does engines told me it worked and damn if it doesn't.