Excellent!! What dyno is it going to? Can't wait to read the results! Would like to know where there is a closer dyno shop is if you can share that, thanks. Derek
A&A Machine in Davison. I want to visit them before taking the engine up there. $600 for the day. Told them I wouldn't need a day so want a face to face and see the shop.
I didn't think I was that bad looking! Was hard to get them on the phone. Then set up a time Sat at 10 am, drove almost an hour to get there and waited until 20 after, nobody showed up. The place didn't even look like a working business was there. Figured to cut my losses before I paid for any work.
Made 7 dyno pulls today. Need to go over the results before posting the numbers and different things I tried. Will say it did make 340hp. Will follow up in the next couple days.
Very respectable number for a "stock" class engine! Nice job Steve. Just think what someone can do with ported heads!! Derek
Heres the full story. I decided to have the pulls start at 2000 RPM thinking with my low stall converter it would simulate how it runs at the track better. Now I know it was like starting from a dead stop in 3rd gear. The dyno did not take into account the low load as in starting from 1st gear. Also the throttle opening was timed and was not a good match for a vacuum operated secondary carb like a Q-jet. The secondary side opened slowly and when the boost ports were dumping fuel the A/F meter went way rich until the air valve opened past about 40 degrees. On the street or track this is not apparent or at least not noticed. All runs were at about 170 coolant temp. Unless noted only ran the OE dual snorkel air filter base, no filter or lid. Same dyno max mufflers as on the car. 60 degree air, 29.12 baro, 40% humidity. Run #1 with 18 degrees initial/ 38 total timing I had 322hp @5600 and 380tq@3800. 14.5 on A//F wide open. Run #2 leaned out the secondary rods. Got 333hp@ 5600, 377tq@3900. Run #3 timing at 16 initial/ 36 total. Got 332hp@5700, 376.4tq@3800. Run #4 different secondary rods to lean out the extra fuel when the secondaries start opening. Got 337hp@5600, 380tq@3900. Run #5 added the filter and lid. Got 328hp@5600, 372tq@3800. Run #6 removed plenum divider. No filter or lid. Got 341hp@5600, 373tq@4100. Run #7 changed secondary rods to richer tip but the taper was smaller and went too lean. run aborted. Interesting to note the open plenum did show the most HP but gave up tq, 11lbs between 3200 and 3600 Just like it does at the track where it slowed about 3 tenths. Wish I could keep the HP without the tq loss. With a higher stall converter (2800) and more gear it would be quicker. Unfortunately I can't run those. Idle quality and low speed driving does suffer with the open plenum. Lost 1.5" vacuum at idle. Fuel mileage also dropped when tried in the past. Interesting note 2; Breathing thru the 72 style dual snorkel air filter cost 9hp and 8tq at peaks. If it where breathing hot underhood air the difference might not be that much. Note 3; torque was real flat from 323@2000rpm to 320@5600, always peaking around 3800 except when the plenum was opened and peak jumped to 4100rpm.
Great stuff Steve!:TU: A guy doing a similar build using lighter stronger rods with light pistons with say a roller cam setup for more RPM would have an even angrier beast, throw in some head porting OR the new TA aluminum heads and N/A pump gas street friendly drivable mid to upper 400 HP would be easily obtainable! Excellent work Steve! Can't wait to here what the car runs at the track with the new slugs in it, thanks for sharing, please keep us posted. And oh yeah, I am possibly taking a ride out to Dave's shop this weekend if in you're interested?(I want to go and see his new line hone machine) Derek
Those are some great results, nice to see dyno numbers. I believe we have somewhat similar set ups, so I was eager to see how your engine performed... :TU: It's time for me to dump the S-divider and get my SP3 installed.
I just happened to be reading this back over to remind me what Steve did here, and came across this.. Ya know Gary, I can look the other way when your exposing on how exhaust manifolds "scavenge", and just chuckle when I skim the "single exhaust is better than dual thread, but I am going to have to fly the BS flag with your above statement, less someone really believes any of that. I have two words for you. Offset Pins... makes even 2618 forged pistons that fit at .0045 dead quiet at startup. I have sold/installed hundreds of them my Diamond piston Equipped 470 motors, and can attest that they are silent. The 4032 stuff like Steve has here usually fit in at .003 and if designed correctly, will be relatively quiet at startup. Nothing like your describing. Once again, I have sold and installed hundreds of them. And none of the other stuff you say here is remotely true.. maybe in 1969, but not today.. Ring seal technologies, the use of honing plates, and surface finish advances, and piston design improvements make the forged piston equipped motors of today.. pass less oil by the rings, need less maintenance and make more power. Even a dead stock engine benefits from the installation of quality forged pistons, with absolutely no downsides, but yes, you do get what you pay for. ----------- Good Job Steve, be interested to see what it runs in the car. I would suggest that you convert all your track times to standard atmospheric conditions at sea level. This factors out the weather and altitude changes from track to track and day to day. JW
I'll back up Jim's post on forged pistons. I can cite much looser clearances and more severe rod angles than usually seen on Buicks without any noticeable piston slap. I've done more than a few with the offset reversed without noise...not a whisper quiet exhaust though... I've also seen a hyper. cast KB set with .011-.013 clearance only exhibit a trace of rattle on cold starts, for just a split second. All of the skirts did crack in short order, as would be expected. 4032 has "higher" silicon content for lubricity and less expansion.
That's an older post quote from me, and yes I can be wrong. Unlike some others, I have the balls to admit it when I am. NO ONE here is perfect Jim, not even YOU. Attempts at character assassination is so unbecoming of you, Jim. I must say I'm rather disappointed. ***EDIT: If I were feeling particularly malicious, I would say that you only did this because it pertained (indirectly) to a product you endorse that revolves around your life's work. So I guess I can understand why you said what you did. Translation: don't attack the money, or you will be eliminated. Is it any wonder then why all my longevity threads/posts are ridiculed... But in my defense, I have also promoted parts vendors and their products/services, as well as offered up suggestions to new products. They can say it was their idea, I don't mind. I'm not in it for the money anyway.*** Not only are your accusations inaccurate about me, but it clearly shows you did indeed 'skim' over the thread(s) and filled in the blanks with assumptions, but it really doesn't matter. I'm sure you're not the only one who does this, seeing how any 'serious' racer would disregard anything I had to say anyway since I try to represent the stock/mild engine enthusiasts. If you'll notice, I spend less time commenting or offering up advice on racing engines, since that is not my area of interest, though the facts I do introduce into this environment of fallacies could carry over to there as well. If you do not believe my words or my time spent here on your website is beneficial or is harmful to others, then please accept my apologies and delete this name/account from your website right now. Be sure to also delete all my posts as well, since we wouldn't want anyone reading all my BS. OR, you can put it all up in a sticky thread and call it 'Gary Farmer's BS' and let everyone poke at it with sticks and pitchforks. lol We'll chalk it all up to one big misadventure and I'll bow out and let you guys have your fun. Steve: Good job! Those numbers are pretty good when you consider the engine has less than 7.5 dynamic, retarded cam setting, and pretty much no scavenging (no merge/crossover pipe) on iron manifolds! It's a good representation of what can be realistically achieved and reproduced. Gary
Gary, I hope you don't take everyone's posts that disagree with yours personally. (I mean mine, anyways, lol ) My comment on forged pistons was more motivated by always seeing and hearing "hot rodding myths". An extra .001 or .002+ clearance isn't going to be an oil burning turd like people think. That's usually bad bore prep/machine work, ridge-ream deglazed ree-bilt's from 'da garage or sometimes oil additives or anything that prevent ring seal. Same with the "thin cylinder wall/overheating" crap. Bad surface finish, at least that's how I was trained. It isn't so much about torque plates and modern advances as much as basics like cross hatch and knowing how to get your tools to leave the right "peaks and valleys" for the rings to be happy. You'd be surprised at just how much inadequate machining is out there as well as laymen's ways of explaining things.
