It said it was a hypertectic piston. Is that not forged? I was told by a friend you could spray the bottle on those type of pistons. Did I once again assume way too much and listen too little?
The TRW H522P-30 are Hypereutectic pistons, not forged. The "H" prefix stands for Hypereutectic and a "L" prefix stands for forged. Because the alloy is brittle they are not recommended for nitrous use. There are no off the shelf forged Buick 350 pistons any longer. As I said in post# 14, the last two forged pistons were the Speed Pro 2232P or TRW L2343 but they no longer exist. The closest you can get is the Buick V6 Speed Pro ZL2481F pistons. Paul
Well Hells Bells! I suppose the only option if I want a forged piston is to have some custom made? ---------- Post added at 12:23 AM ---------- Previous post was at 12:12 AM ---------- What would I have to do to make the speed pros work. I see they have them in a 3.830 bore but wasn't the stroke and rods size vastly different? ---------- Post added at 12:30 AM ---------- Previous post was at 12:23 AM ---------- Wouldn't they be too far down from the deck at TDC? Or would the skirt be too long and hit the rod?
Below is from the Nail Head forum,on the "having a mini-stroke" thread,If they can make 340 pistons,350 pistons are only .050" bigger,and if they are $550,thats a good price for forged pistons.($68.75 a piston) Originally Posted by wkillgs RaceTec pistons? Nailheads aren't listed on their site.... yours were custom made? It would be great if they had pistons with a bit more compression height instead of the typical 0.050" down in the hole stuff, and a bit deeper valve pockets for using a decent cam. They made my 340ci pistons and now have the specs for the nailhead, yes custom made any pin height any dome size also for the nailhead deep valve pockets even for a bigger valve. mine were $550.00. the guy that owns ractec use to own je pistons.
The V6 has shorter rods and shorter stroke but the block deck height is also shorter at just over 9.5" versus 10.187 for the 350 That puts the CH of the V6 pistons in the same range as the 350 pistons. The Speed Pro ZL2481F pistons have a CH of 1.825 which puts them .050" in the hole and a dish volume of 24.5cc. You would have to take .050" off the block to zero deck the pistons and take enough off the heads for a 54cc chamber. Then I'm sure at that point the intake sides of the heads or the intake manifold would need material machined off to get the intake ports to line up with the intake manifold runners. Push rod length could also be an issue It would be easier to have a custom piston made with a 1.855 CH and a 20cc dish. The block could be decked .020" for zero deck piston clearance and to get the block deck true. The heads only would need a small clean up cut and with a .040" head gasket the stock length pushrods will still work. Paul
It all sounds like way too much when all I have to do is forget about spraying and keep it simple because anything I do is going to be better than what I have now. Stick with the cast piston and stronger later rods and stop with the mental masturbation because from what I've been reading. There is pretty much a ceiling of 375hp with this build anyway and anymore than that will break the bank. If I give in to my mind then it'll be just me and the car because my wife will divorce me.
The TRW H522P uses a tighter piston to cylinder wall clearance since they are a Hypereutectic. Quieter cold running. The only other cast piston is the TA which is actually made by EGGE Machine Company Part Number: L2343 As far as I can tell both pistons have a 12cc dish and a CH of 1.855 That gives right at 9.9 compression ratio with a .040" head gasket and 58cc head. If that is true, this is where the .060" head gasket is needed. Need to call EGGE and double check piston specs. Paul
Jeff.. Just to throw something in the mix.. I used the early stlyle rods with hyper pistons and 8lbs of boost to make something close to 500 HP and beat the living snot out of it.. Bouncing off the 5800 rpm rev limiter on MANY occasions with the stock bolts too..
I know exactly how you feel here bro. I came in here some time back thinking I'd ask a few questions and get some ideas ironed out, only to discover I needed to spend more time in here picking their brains! I'm no novice by any stretch of the imagination, but these guys in here are incredible on just how much there is to know. Awesome bunch, glad I met everyone here. :TU: ---------- Post added at 10:15 AM ---------- Previous post was at 09:43 AM ---------- Lol...if you let these guys guide your spending decisions, you'll be in trouble for sure. I had to put a stop to that damn quick. Hey use this, no use that! Meanwhile, the receipt at the checkout counter is ding ding ding'in up for us regular guys who don't have thousands laying around in the bank waiting to get spent on something! There are a few core items you MUST have done, and you're going to spend money on that, no way around it. But the rest of it you can get away cheaper on as long as you don't let your imagination run wild on you. Personally I'd rather have fun in a car that burns rubber and corners well and gets more than 15 mpg that I can enjoy for many years to come than to have some balls-out screamer that might last a year or two before it needs rebuilding all over again. 350-375 hp and 400-425 ft. lbs. will do exactly what I want. Who gives a damn if it's not the fastest thing on the road, I learned a long time ago that no matter what you got, someone's got something faster, so the sooner you can come to terms with that the better off you and your bank account will be. :Brow: You originally wanted a 10.5:1 with the TA 212 cam. If you use that cam, your compression is limited to 9.5 static (yeah, there's two of them now, the static and dynamic compression ratios) the dynamic is what you pay attention to. It's the piston's relation to the intake valve's closing position. Static is bdc to tdc, dynamic is when the intake valve closes abdc to tdc. It effectively shortens the compression stroke distance and hence dynamic compression, and will be (one of) the determining factor(s) on which grade of fuel you'll need to use. BTW...did these guys give you the skinny on quench yet? And I don't mean chugging a quart of Gatorade while you're working on this little monster, I mean compression to combustion chamber efficiency. That'll affect your detonation threshold as well. I've been told that the dynamic compression ratio should be at or below 8:1 for premium fuel at sea level. The TA 212 cam's limit on a Buick 350 is about 9.5:1 (static) before you run the risk of detonation. The cam next in line above it, the TA 284-88H, has an increased intake duration that allows it to run up to 10.25:1 static compression on the same premium fuel. Nuts isn't it? Doesn't seem like much difference cam wise, but you're looking at a full .75:1 comp difference. The latter camshaft will have a rougher idle, since its .050" duration on intake is 223* as opposed to the 212's 218. I've read anything over 220* is reaching borderline in terms of vacuum for power brakes, but there's ways around that as well...:Brow: The 212 will be better mannered, but the 284-88 is still streetable. You say you already have the 212 cam, maybe you could return it for the 284-88 as long as it hasn't been used? Or if you really want the 212, you'll have to sort out the 9.5 compression delima. It's been described earlier in the thread how to achieve 9.5 comp with cast pistons, and will be your cheapest route. :TU: G
I called EGGE and they only have the 10.25:1 high compression 350 piston It has a 1.859 CH with a 3.06 X .078 dish which works out to be about 9cc. The TRW H522P would be easier to work with so far. Finish Line Motorsports and Automotive Machine Performance are not available today for some reason. They both carry a line of forged pistons for the 350. Paul ---------- Post added at 09:38 AM ---------- Previous post was at 08:46 AM ---------- Got Money? Gary, we simply list all the possibilities and let you choose. Remember that there are a lot of other readers to a thread and someone may find that a certain combination is what they have been looking for. I use a lot of previous threads for reference all the time. The 350 head is open chamber so there is no reason to bring up the subject of quench unless the special dome/step dish pistons are used. AM&P can supply them but it also requires the combustion chambers to be machined so they are identical to the piston dome shape and as you pointed out it cost extra money. Paul
Of course! I meant nothing more than a little bit of humor out of it. It's difficult to discern demeanor sometimes by reading words on a page. My appologies if anything was misunderstood, Paul. We give the readers here something interesting to digest, that's for sure! And as far as quench not neccesary to bring up, I recall a thread you and I were involved in earlier that addressed that very issue. You're der Meister, Paul. /salute G
I spoke with Mike over at AMP and he was kind enough to share previous 350 build particulars with me. After kicking it around with him. The TA 1602 8.5:1 will be just fine for my application. Easy to get, tried and true. Now that I know what piston, let's finalize the mill work needed to achieve the desired CR and DCR. I know the combustion chamber will end up under 60cc. Just how far is yet to be determined. The heads will be done by AMP. Mike said by comparison using other builds, one was 59cc on a set of 72's and the other was 57cc using 70's. The 68's which I'm using will start out smaller than both stock chambers, so logic would tell me the finished product would be somewhere between 56-58cc. I know this info has been volleyed around in this thread but what I'm asking for is a summation using my final choices for parts. Everyday Performance 1979 800cfm electric choke Q-jet, TA 350 stage1 intake, TA 212 cam and lifters, oil through push rods, 69 rockers(the dynamics for this has been addressed in another thread so let's not delve into it), 68 heads stage1 build port and polish at AMP, 68 block .030 over bore with TA 1602 +0.30 8.5:1 CR, stock rods and a stock crank. Desired static CR is 9.5:1 or a little better. So, how much off the deck and head? How thin of a gasket? 1st edit ; The TA 1602 10:1 piston has a 11.8 cc dish so that's the piston I'll use
Jeff.. I'm in the process of building basically the same motor except I have a set of old TRW forged pistons with a 10cc dish and I'm gonna use a little bit different Crower cam.. Here's a static compression calculator.. http://www.rbracing-rsr.com/compstaticcalc.html
Ok So I punched in these #s. I just need y'all to double check my work if you would. The bore is 3.830, stroke 3.85, gasket .040, deck .020, piston dish vol 12cc and a 57cc Chamber makes 10.04:1 SCR
I get the same result. Call it 10:1 The TA 212 cam set with the intake lobe center at 106* ATDC closes the intake valve 58.5* ABDC. The DCR is 8.4:1 Paul
Did you measure the piston depth?? Last one I did was .058.. If the deck height is .058.. Then you are at 9.3..
Although the 350 doesnt have a true quench pad on in the chamber/deck to speak of, i still cant wrap my fingers around why anyone would run the piston down in the hole some Has anyone actually run one this way,then back to back tested against a 0 deck combo ,and lost /not made more power? I cant see it NOT MAKING MORE POWER?
I was actually thinking about giving you a bad time all in the spirit of fun but I had to go and couldn't take the time to come up with something witty. No worries . Thanks for the concern. As far as quench you are absolutely correct. Just because the piston to head clearance isn't .040" doesn't mean quench goes away. It is just less than optimum so trying to get zero deck even if there is an open chamber is still a better approach. Thanks for keeping things in line. What I should have said is: It has been such a problem finding an off the shelf piston combination to get 9.5:1 compression that I would be happy with whatever quench resulted. Paul ---------- Post added at 03:13 PM ---------- Previous post was at 03:08 PM ---------- The TA 1602 pistons have a CH of just over 1.855 which puts them .020" in the hole at standard deck height Paul ---------- Post added at 03:23 PM ---------- Previous post was at 03:13 PM ---------- Nick It is because there isn't any non-custom pistons available with the correct dish volume and/or CH to get you 9.5:1 at zero deck. You would need a custom piston with a 20cc dish and a CH between 1.855 and 1.875 depending on how much the block needed to be decked to get it true. Then there is the choice of spending the extra piston money on the car and having to live in it because the wife kicked you out. Paul
