Today the pistons for very first TSP "Triple Nickel" (555ci) came in. I had to chuckle.. even to a guy like me who is used to working with the "coffee can" size .038 over 455 pistons, these things are big.. (4.500 bore for the new TA block). Here's my new piston.. Compared to a stock 455 cast piston.. And to my 470 Diamond piston.. Note the thickness of the top at the outside of the valve reliefs.. The exact same symmetrical relief program was used on both of these pistons, since all my stuff is set up to clear 2.260 diameter intake valve. The dish in the 470 piston makes them look different, but they are the same. Lots more material outside the relief is an easy tell for how much bigger they are. This first set is for a NA race motor, to be fueled on E-85, so compression was held to 12.75-1, with the customer's 66 CC heads. This required an ever so slight dish in the piston top. Lateral gas ports and the very slight dish are evident here. Since this will be an often used bracket motor, and not a "twice a year raced" piece, keeping sufficent skirt on the piston is key for low piston rock and good ring seal, over a long period of time. If you spend 15K on a shortblock, you don't expect to take it apart every year.. and those very short skirt pistons we used to use with 7" rods in the iron strokers were hell on the cylinder walls. At 630 grams, this piston is a nice compromise in skirt length vs weight, in my opinion. You can see it's not all that much shorter than the 470 combo piston, and uses the same rod length and pin diameter. The difference of course is due to the longer stroke of the new motor, somewhat offset by a true 10.570 deck height. I love cool new parts.. makes the job interesting. JW
Re: Triple Nickle Pistons.. Jim how about taking us along for the ride on this one and posting updates - dyno numbers ...this build is going to be great .....J
Re: Triple Nickle Pistons.. Sure can.. This will be what should become with time a very common race motor build. Built for the bracket wars, so nothing tremendously exotic.. just a durable alum rod, forged crank shortblock, with a set of TA STG 2 TE heads on it, single plane with a dominator set up for E-85. Mild roller cam for long life and lots of passes. Going in a mid 80's Regal drag car, that ran 10.30's with his old 494. He sent the complete engine to me in hopes of just repairing a rod bearing issue, but the iron block had 2 spun mains, and with a girdled motor, that's an expensive propostion to fix, and they never really turn out perfect. He picked it up used here a couple years ago, so he got some time out of it, but it was time to move on. Add that to the fact that he wants to go faster, stepping into the alum block made sense, instead of trying to fix that old iron stuff, and then hoping it would live for a while at 750 or so HP, with the big solid roller cam he would need to step up the power. Nice to have options these days, if the budget allows you to explore them. His did, and here we are. It will be a while yet, crank is on order, so this should happen later this winter, if all the parts show up in a timely manner. JW
Rods Today, the rods for this motor came in. GRP alum 5001 series 6.800 Length .990 pin 2.200 big end 630 gram total weight ARP 2000 bolts Standard material rod, good for up to 1500 HP. Kinda gives me a "rod"... :laugh: :shock: Nothin' better than spending other people's money on speed parts. At least until it goes out the door.. :ball: JW
And it goes in this.. I can attest that with the caps removed, I have no problem lifting this block off the table, setting it on the stand ect... I couldn't even think about doing that with a grout filled bare iron race block.. JW
After machining.. Machining requirements on this block Bored to 4.500.. we tested the hone with and without a deck plate, and found that the block pulled less than .0005. I will do these in the future, even to this bore size, without a plate, with no worries. Saves Money and time.. We o-ringed the sleeves, and used just a .010 over the sleeve stick out for the wire, and did not put a reciever groove in the head. Basically what we did forever with the iron block, and at this compression level (12.75-1) naturally aspirated, I felt the money invested in reciever grooves would be wasted. Deck height was 10.570 +/- .001- We did not deck this block, as the Sleeves were .002-.003 above the block surface, which is desirable, to let the block grow up around the sleeves. If I had to deck the block, I would have removed all the sleeves, and decked it, and re-installed the sleeves, to maintain this critical dimensional interaction between the block and the sleeves. I was very happy not to have to do this.. :TU: Main housings were .0002 under low limit.. we left them there. Only a light deburing was required on the main caps. With standard main bearings, and the crank at just under low limit, main clearance was .0022, which is in the range I want for an alum block. .0018 to .0022 was our goal, as when this thing warms up, main clearnance will be up past .004. Lifter bore placement, angle and size was right on the money, finish of the lifters bores was exceptional. No work was required. So in short, take it out of the box, and bore and 0-ring it. We did spend considerable time and money checking everything, as we had no history with this piece. JW
Cam and bearings.. This is the prototype set of TA 4550 Tomahawk block cam bearings, at the time they were installed, the only set that existed. The standard 460 Ford cam bearing is about half this wide, so I elected to go with this new bearing, and was very pleased with the decision.. these feature a slot to align the oil hole, a single back groove, and two extra oil holes, and are Teflon coated. Installation was straight forward, and I finally got to use one of the other adapters in my cam bearing driver set! The edge of the block was broken with a light emery cloth before block wash, then after the block was clean, I oiled the back of the bearings and the pounded in perfectly. Cam bearing clearance was .0025, with .004-.0045 press fit of the bearings. The camshaft is a solid roller unit, 270/280 at .050, with .400 lobe lift. His STG 2 TE heads only flowed 345 at .600, so I kept the cam lift on the conservative side. .630 with his roller rockers, with the valvesprings right at 600# on the nose, to help keep the rockers/valvesprings alive, on a motor that will see over 200 passes a year, in bracket racing. The only area of concern was the thrust surface on the rear of the camshaft. While the bearings are bigger, the thrust surface remained at the standard 455 size, which allowed only a very small thrust lip. We debated counterboreing the block face, and using a one piece torrington bearing here, but in the end, decided it we were making much ado about nothing. The reality is, the cam floats in the block, set at .006 end clearance, so I just simply got ahold of a couple of .030 hardened steel torrington bearing races, at 2.5" ID/2.85 OD, and then carefully tig welded them with 3 small tac welds, around the OD of the race, to the steel cam hub. IN the picture below, you can see the small thrust area, and how the washers greatly increased this. These cams are electric pump only, as they have no fuel pump drive provisions. The cam fit the block perfectly, with about 3 inch pounds of turning torque with oil. The rear cam plug accepts a standard 2.25 inch deep cup plug, as it is much deeper from the back of the cam, than a standard 455. Note the extra bolt holes near the cam tunnel Those holes are there to allow the installation of a cam plug retainer plate. Now, with this deep cup plug, installed with the normal Permatex #1 sealer, I was not really worried about the plug popping out when the block expanded, but then again, if someone took the time to lay out and add the op to drill and tap the holes, why not use them? So we fabricated a retainer plate, from .062 aluminum sheet. I then secured it with 2 button head 1/4-20x1/2 bolts, with loctite. On the front, Since there was no concern about interference with a fuel pump arm, I selected grade 8 5/16x3/4 long bolts for the timing chain top gear, and then used a nice high collar lock washer with them, and locktite. The bolts were ground to be exactly flush with the rear of the cam hub, when installed, thus utilizing all the thread area. And of course, don't forget to install the lifer bore galley plugs behind the timing chain.. these o-ring, screw in plugs, are first class pieces, just like all the plugs in this block. JW
Speaking of plugs.. one thing to watch out for.. When the block originally arrived, I took all the plugs out and threw then in a ziplock, to prepare the block for machining. After the block prep was finished, the first assembly step was the plugs, and I simply matched the plugs up with the correct size threads, and screwed them in. When I put the timing chain on, I noticed that the plug I put in the priority main oil galley, was just about touching the back of the timing chain. At first, I though "man, am I going to have to grind that plug face".. but then, after thinking about it, I came to the conclusion that considering the thought and design excellence that was put in this thing, there is no way they missed that.. Sure enough, I put the correct plug in the rear of the block, you can clearly see the thin-head one in the driver side lifter galley at the back of the block in the above pictures.. Here is the comparision.. the plugs are identical, except for the head thickness.. With the proper plug in the hole, there is plenty of timing chain clearance. Easy mistake to make, make sure you don't! JW
Crank install.. Let's back up a bit, and talk about hanging the crank in this thing. Or as I was referring to it "assembling the jewery".. First off.. I selected a Federal Mogul Race bearing set for this one, as I felt this was the best bearing for a motor that is not going to come apart often, going several hundred passes, between freshen ups. It's a very nice bearing, with a big oiling slot, and a 3/4 groove. Because I had the groove available in the housing, behind the bearing, I then drilled 1 hole in the oil groove, so oil can enter the bearing from the rear, and not be affected by the spinning crankshaft, which tries to push the oil out. No hole was required on the other side in my opinion, as that same centrifugal force will pull the oil out of the main slot, and push it in that direction. Now, I did several cap fits on this thing, checking out the fit and sizing of the bearings, as well as the rear seal. One thing was evident, from the very first time I took a main cap off. Wow.. are they tight.. I used the pry slots on the side of the cap, and carefully worked it off, but the interference fit of the cap, makes it difficult, if not nearly impossible, to "cock" the cap, to pry it out like that..it need come straight off, and then straight back on. I put the #2 cap on once with a brass hammer, and I can tell you that there is very little chance you will be able to keep the bearing half in the cap, beating on it with a hammer. And this is not a "beat on it" piece of equipment, at least not if your walking upright with the rest of us.. :shock: Now, apparently this is not an uncommon situation for an aluminum block, and one of my machinist suggested a solution. There is a 5/16-18 hole tapped in the center of the cap, and that can be used to relatively easily remove and install the caps.. with a big axle-pulling slide hammer. Sounds crude, but actually works really slick, and it's the only way to work with these caps. You need to build an adapter, and I would encourage TA to make these available.. it's actually pretty simple. A 1.5" diam piece of hot rolled steel, 1.5" long. I located the center, and drilled thru the entire thing for a 5/16 thread.. but before tapping it, I then drilled thru 2/3 of it with a 37/64 drill, which was the size for the 5/8-18 thread on the shaft of my axle slide hammer. I then tapped the 5/16-18 side for a 1" allen bolt, and threaded the other 2/3 of it for my slide hammer. Pictures tell the story better than words.. The adapter is then tightly screwed onto the cap.. And then you tightly screw on the slide hammer.. This gives an excellent, stable platform to drive the cap on and also to remove it, straight.. It worked perfectly. Setting the end play. Be prepared to spend some time here. Measurements indicated that I had basically zero end play, with the bearings out of the box. So off to the solvent tank we went, with a piece of safety glass, and a sheet of 600 wet dry, for some careful, and time consuming sanding of the thrust surfaces of the center main cap. After installing the center main, I got the magnetic base dial indicator out, that I have used on a hundred BBB builds in the past, and stopped dead in my tracks when I turned and looked at the block.. hey, that thing is not magnetic.. so it took a bit of thinking.. :idea2: This one is a bit touchy, keeping the end play while installing the caps, so I advise that you check it, every time you put a cap on. End play was set at .007. When I see this motor again this fall (after it's 200 passes), I will be looking closely at the thrust surfaces on the cap and block sides of the center main, to determine what, if any, influence the alum block vs steel cap, has on the thrust bearing. One thing to note.. the main caps do not register on the block, like an iron block does, but actually the alignment process happens between the cap and the stud, you can see the raised area for that interface in this picture. The other thing that became evident, was that there is a requirment for a short bolt in the passenger side bottom bolt of the timing cover. You have this much thread, before it hits the outer stud of the front main. JW
A few more shortblock pics.. Which brings us to camshaft.. As I said before, this is not a run 10 times a year at a couple events motor.. it's a down and dirty, every weekend bracket racer, and as such, durability was much more important that squeezing every last HP out of it. So with that in mind, I selected the solid roller cam.. one thing that has always been an issue with the .700 lift rollers, is rocker arm durability. Guys have spend a whole lot of money on this one.. trust me the $750 for a set of TA rollers is peanuts compared to going with a set of Jesel rockers, and all the work it takes to put them on. So for this project, I kept the cam at a reasonable lift .. .610 intake/.660 on the exhaust.. this allowed me to work with a set of comp cams valve springs, and keep the open pressure down around 580lbs, which is nothing compared to the nearly 800 lbs I have run on solid rollers in the past. Cam duration is also reasonable, for this cubic inch .. 274/278 and it's ground on a 108 center.. It was a 4-7 swap deal, and it degreed in right on the money. The roller lifters were another first of the breed.. Mike actually had crower put these together for me, and he was more than interested in how they would fit in the block.. the 1 motor that was built from the prototype run of 5 blocks, had to have the tops of the lifter bores machine for clearance, when the roller was on the base circle. This one was the first with the large diameter roller cam, so that clearance was in question, but it worked out just fine, no screwing around required.. And then once again.. had to re-think how to do something I had done hundreds of times before.. can't use the magnetic base for the indicator on a Alum block! JW
Oiling system As many of you know, this block has what is known as priority oiling for the mains.. simply put, it has another main galley, that feeds only the main bearings, and thru them the rods.. It's the reason for the third hole in the front and rear of the block, right around the cam tunnel. These two pictures, of the front and rear of the block, will help clarify how it's different, and how it all works.. The priority main galley oils the mains first. The feed hole to the block, from the timing cover output is not drilled thru, so if you want to feed oil pressure in thru the hole in the passenger side (traditional sender hole) or at the rear of the block, you won't have to worry about plugging anything- this engine used an external feed line from the pan to the TA scavenger pump plate, pumped it thru a external filter mount, and then back into the motor, thru the traditional sender hole in the passenger side (which is 1/2 NPT tapped) At the rear of the block, we see this.. Here is how it works.. Oil is fed down the priority main galley.. to the mains, and then out the back, up to the crossover tree, on the back of the block. An oil pressure feed hole is right there (labeled oil feed in the pic) I used this hole for the oil pressure sender feed, in a dry sump or belt driven external wet sump pump, you could feed oil in here. The oil is fed to the traditional lifter galleys, by the "tree" and they have to go past the oil restrictors.. this limits the amount of oil up to the top of the engine. This is the oil restrictor.. The "restrictor is actually a Holley carb jet.. in this case, a 70 jet size is installed. And as they are installed in the block.. Now, the threaded hole in the center of the block, between the two restrictors, intersects with what I labeled as "plug for lifter valley drain hole" in the first pic of the rear of the block. This threaded hole is used for evacuation of oil and vapor out of the top of the block, when using a dry sump, or a vacuum pump. What all this extra stuff does is simple.. 1. the mains get oiled with full pump pressure, instead of having it bled off by the lifter bores. 2. the oil to the lifter galleys is restricted, thru an external pair of plugs, to limit the oil to the top of the engine. 3. Provides an extra oil pressure input, as well as a suction output. JW
I've been waiting for this Tomahawk fix for a long time. Sure feels good. Excellent job of explaining, thanks Jim. I'm hoping the next installment and the dyno pulls aren't far down the road.
Hi Paul. I know you have been patiently waiting, we will finish this up in the next couple days. Oil pan.. Another first of it's breed, built by SRE.. Steve had a block previously to do some templates with, but this is the first production block pan.. he would have to chime in if it was the first one period for the Tomahawk block. You note in these first pictures it's not completely welded, he tacked it up, and set it to me for a final test fit. bungs for an oil heater and temp sender External pickup -16 size baffles were left out initially.. The thread in Steph's oil heater Next thing to do was to check to see if a dipstick tube would clear the rotating assembly.. Yes, it will.. The finished pan a better look at the heater.. The pickup And installed JW
Timing cover/oil pump Pretty straight forward here, with just a few wrinkles. I used a new TA cover, and then their Scavanger plate system. The use of this requires some modification to the new timing cover.. 3 xtra holes drilled in the cover- these provide some additional oil to the inlet side of the gears, the majority of it flows in thru the cover itself, but a little extra suction side oil never hurts. And then plug the factory inlet hole.. to insure no loss of suction. After this picture was taken, I filled the cavity with epoxy, over the plug, just to insure it was airtight. Nothing needs to be done with the factory pressure passage in the cover, the plate does not use it, and remember, there is no hole drilled in the block for it. As installed, with standard length gears.. Note I had a custom 1/2 NPT to -16 fitting built, my experience in the past taught me that a -12 feed line to the pump can be marginal in some situtations. IN fact, the block has provisions for a 3/4 inch pickup tube, and the next motor in line here will be built with that. Simple is always better, and external lines are a pain. The next motor is actually a supercharged/FI one, but it is going to be baseline tested with a carb, and I am going to use a stock oil pump setup in that test. If it will pump enough, it will make things a lot simpler. The biggest challenge for the customer when installing this motor, was fitting all the lines around the frame and mounting the filter ect.. It has an external by-pass, so you have to have a place to dump the oil back in the motor, so we tigged up a fitting, on an aftermarket fuel pump block off plate. Makes for a good timing chain oiler, and since there is no fuel pump eccentric on the large journal cam cores, an electric fuel pump will always be required, at least with the current parts available. The only picture I have of the complete system is on the dyno.. And here is a related video.. Working with a whole bunch of new stuff, I left nothing to chance.. we pre-heated the oil with the oil heater (worked slick) and then spun the pump, with the intake off, and watched it fill up the motor.. I was curious if a 70 jet in the restrictors was enough. Several builders with extensive alum block experience told me to use the 20-50 oil, and since we have pre-heat capability, room temprature viscoscity was not a concern. <iframe width="560" height="315" src="http://www.youtube.com/embed/Gyr6I1ZW1l4?rel=0" frameborder="0" allowfullscreen></iframe> I should have added in the video.. we have pressure and flow... all that oil you see in the heads, under the valve covers, was pumped their, thru the pushrods and rockers, in the time that drill ran.. the system was dry when we started, and there was no oil standing in the heads. It pre-lubed and filled the top end, almost instantly.. So we backed off on the oil restrictor hole, found a set of 25 Holley jets from a 2 barrel.. You can see the size difference.. 25 on the left, 70 on the right. JW
Hi Jim, Good thread!! (Nice Oil Pan too!! lol) That was in fact the first Tomahawk pan. Since then I have done about a half dozen of them. I think my jig worked out well with the exception of the internal oil pickup. At the time I was building the jig (based off of prints and an actual prototype block), the people that I had referals with told me to not be concerned about the internal oil pickup as not many (if any) would be using them. Looking back I should have just designed this feature into the jig! Hindsight always seems to be 20-20!! I'll need to find a way to incorporate into my existing jig. Looks Good Jim, keep it going!! Steve
Cylinder heads and top end Nothing exotic here, a pretty conventional STG 2 TE head package, with an SP-2 intake, and E-85 dominator. We did have to make the TE's worthy of the project.. they were, without a doubt, the worst set I had ever seen. Here are the before and after numbers. And a pic Bolted them on with the .050 thick copper head gaskets. With number 1 cylinder set up for mock up testing with checking springs. And finished it up.. This is the last motor picture I have, before the dyno.. About this time the customer stopped by, and we finished it up, but I forgot to take the rest of the pics during the process.. With the guys standing right there, it becomes less important. Didn't think about the website at the time, but the rest of it was pretty straightforward. One word tho.. Never ever trust anything.. the customer gave me what looked like a brand new Q/F E-85 Dominator Didn't look so new when I popped the bowls off.. he had been running this thing on his 494, 3 months earlier. IMG]http://i150.photobucket.com/albums/s110/tspjim455/Erickson-%20555%20Tomahawk%20E-85/100_4996.jpg[/IMG] Can you imaging what would have happened to this brand new motor, if I started it up with that thing on it? It's stuff like this that causes many a "I built a new motor and it failed, so (insert whoever or whatever the guy did not like ) screwed it up.." The customer was there, and out of curiosity, I asked him "would you have just bolted this carb on?".. he said "Sure, it worked last year just fine". The cardinal sin--- never trust any carb, I don't car if it was on the car that your folks drove to the hospital with to have you.. stuff happens, be smart. And on to the dyno testing. JW
I didn't take any pics Devon, but the heads had quite a bit of work done to them.. they were big as far as port volume, it just the shaping/blending and valve job/chamber work that was the issue. JW
