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As stated Tim’s current 400 pistons are really only intended for open chamber heads. I’m not sure what effect 0 deck pistons have with the stock open chamber 400 heads but lots of guys have used his pistons with stock heads and done well.
I have read articles about needing or not needing dual quench. Some say it’s helpful to reduce detonation and others say the smaller quench pad isn’t big enough and the main quench area overrides it.
Either way these are Tim’s closed chamber pistons designed for the Aussie heads shown behind the piston. These are 30cc dish with a step to 0 deck and give a 9.4:1 compression with 58cc Aussie heads. Tim no longer makes these pistons. I wonder if the current open chamber pistons could have the tops machined to increase dish?
I would think Tim’s current pistons would work good with the trickflow 72cc chamber heads.
Thanks for that picture. I am sure the TM piston would run ok with TF heads but it can be so much better. I am not trying to bash TM, I am glad someone is making parts for these. All I know from years of building cars is no detail is too small. The smaller quench area may or may not promote detonation depending on the conditions. I know if there is not a .110 space for detioning, then i wont have to worry about it.
It is easy to have ~5-6k in a total motor upgrade, (and this is nothing crazy) The machine shop bill for the block was ~1600.. hot tank, shot peen, bore, hone, line bore, cam tunnel hone, cam bearing, freeze plugs, file ring gap and assemble. I know I am missing something but making the point that if the motor is down to this level, 400$ more for a set of custom pistons is cheap. I would think a few hours on the CAD and Whoever machines TM piston could leave the entire piston at zero and machine the valve relied and a ~15cc dish instead of a step.
My 78 Bronco is originally Medium Copper, in fact it is the bronco version of your truck. 400/c6, brown lowback bucket interior, Ranger XLT, etc. . One of the paint ideas I've had is including a similar orange pinstriping to what was original on the trucks. Its pretty cool to see yours in original color with the pinstripes. Do you have any more pictures?
Once you get the motor figured out, it could be a great recipe for others. One thought I had was doing a similar motor with fuel injection and swapping in a 6R80.
Thanks for that picture. I am sure the TM piston would run ok with TF heads but it can be so much better. I am not trying to bash TM, I am glad someone is making parts for these. All I know from years of building cars is no detail is too small. The smaller quench area may or may not promote detonation depending on the conditions. I know if there is not a .110 space for detioning, then i wont have to worry about it.
It is easy to have ~5-6k in a total motor upgrade, (and this is nothing crazy) The machine shop bill for the block was ~1600.. hot tank, shot peen, bore, hone, line bore, cam tunnel hone, cam bearing, freeze plugs, file ring gap and assemble. I know I am missing something but making the point that if the motor is down to this level, 400$ more for a set of custom pistons is cheap. I would think a few hours on the CAD and Whoever machines TM piston could leave the entire piston at zero and machine the valve relied and a ~15cc dish instead of a step.
Chris
I agree with all of that. It will be interesting to see what your quote comes back at.
If your custom pistons are 0 deck all around, no step and dished for a 60cc combustion chamber it will be interesting to see if it needs valve reliefs for intake and exhaust and if that will just give the effect of two steps.
FYI - in 1992 i had a 429 Ford rebuilt and balanced for my Ford Van E-250 series at supposed 9:1 comp.
I had a Ford tech remind me about exceeding 9:1 for running on pump gas and "pinging" pleasures.
I know everyone will disagree, but i wound up disconnecting the vacuum advance and ran only mechanical advance. For what ever reason i was happy, and the engine was happy and never overheated while giving those 7.3 diesels a run-for-their-money while towing. I am running a Holley 3310 on the 429.
Enjoy your build, and watch for valve relief and pinging.
your supercab looks to be a very nice pickup to be proud to drive !
Last edited by Greaser007; Jun 8, 2021 at 12:40 PM.
I came across Dss racing in my searching. They have a number of 400 pistons, including a 13cc d dish, 1.710 height. Looks like a good starting point if they’ll do custom
I spoke to them, they can make a larger cc but it also will take ~6 weeks. I might go ahead and assemble this motor and if I have issues the easy fix is ordering a set of 72 cc heads. I can sell the 62s to someone with OE pistons or a 351 and it will get them 9.5ish to 1 and should run great.
The motor is back in the truck, I am just pushing this POS uphill.
It is now an 11-1 motor with a Comp 282s cam. .570 lift, 236@.050. I have been battling Rocker arm geometry for a few days and just in case anyone is going to use Trick Flow heads. The only Rocker that fits right is the TF 1.73 rocker. Most measure 1.650" from the trunnion to roller and it needs to be 1.550" TF is the only one. Using any other rocker make for some ugly geometry. I have a post over at Hotrodders in more detail.
In the link, the sweep across the valve stem looks wide, like over an 1/8 inch. I am thinking the his push rods are way short.
Scorpian most likely makes the for TF. The Trunnion, roller tip, clips etc are identical.
From what i gather,,(first ford motor i have built) Maybe the OE heads required a rocker of 1.650 trunnion to roller. TF could have moved the valves in the heads for better flow. My AFRs are not in the OEM locations.
Can you measure your scorpians? PM me with you phone number is you want. Might save you some time and headaches
You should be good. The trick flows are only .010 shorter and that will not make a difference. FWIW. my block was cut .015" and i am using a ..060 head gasket. Maybe .005 taller than stock.
That said,, I found that a 9.700" pushrod workerd out the best
Hello all,
I thought i would give an update. In the end the motor is ;
400 .040 over
11-1 with the TMyer 13cc pistons
TF 62 CC heads.
Comp 282S cam. 570/282 235@.050
Trick Flow Rockers.
Comp Magnum pushrods 9.700"
ARP 2.10" studs. Not enough thread engagement with the 1.900" from TF.
standard oil pump pressure/volume.
Weiand dual plane intake.
quick fuel slayer 600CFM vac secondary.
Pertronics distributor and coil.
here is a quick video, pardon the spaghetti wiring, I am waiting for my laminated diagram to come. I have removed the external regulator and ignition so there is a lot to remove. The cam is a lot mellower than i thought it would be, Idles effortlessly in gear at 700 rpm. Consider the 294S in my 406 dart sounds very radical.
I will report back when i finish the front end and have a few road test. The timing is set at 15 btdc for the break in. I will be curious what it will like with 91 octane and this combination.
