rmchrgr
Skate And Destroy
Back in April of 2016 I put the first version of my 416" engine on a dyno to break it in and see what it would do. It's a factory 340 block (I bought off @stroked340 in the ETown pits many years ago) bored .030" over, Diamond dished pistons at zero deck, (10.3:1 c.r.) IMM CNC RHS/LA-X iron heads, Comp 251/259 @ .050" solid FT cam, Hughes 1.6 rockers, 'gasket-matched' Holley Strip Dominator intake, OOTB Proform 850 carb and TTI W2 1 5/8" step headers.
I thought it would realistically make around 525hp. When I got to the dyno shop, the operator laughed and said yeah sure, we'll see. It ended up making 500 hp on the dot and 502 lb. ft. of torque. The dyno operator was genuinely surprised and impressed but I was disappointed that it didn't hit my number. There were a few things holding it back (not the heads or cam) and trying to understand how those choices impacted the results led me to revisit what I had done to that point. I opened my eyes to a a bunch of stuff so it was a good (but expensive) learning experience.
If you're inclined, the link below will provide some background on where this project started.
https://board.moparts.org/ubbthreads/ubbthreads.php/topics/2055372/re-416-on-the-dyno.html
BTW, @PRH was generous with his time back then in helping me understand what I was looking at in regards to the dyno results. I still appreciate that and carried some of his insight with me to now. The dyno shop owner was very surprised that I even knew what BSFC is and why it's important and commended me on that so thanks again Dwayne.
For various reasons, that first version of the engine never ran again so fast forward to 10.24.25. I won't detail all the boring crap that took place over the last 9 1/2 years but let's just say "I saw the light" during that time and this is what it looks like now;
Bloomer Performance aluminum cylinder heads with PAC springs and titanium retainers (and I believe Ferrea valves?) @BPE
Diamond flat top pistons for approx. 11.3:1 compression
Cometic .0039" MLS gasket
Bullet 263/268 @ .050" solid roller cam, .665" lift installed at 104 (they started me at 272 @ .050"!)
Comp 8043 lifters
Manton 5/16" pushrods (yes, 5/16")
Home port-matched Super Victor intake Super Victor port matching
Moroso electric water pump
TTI 1 7/8" headers
Precision HV oil pump
Left over from 2016 are the block, crank, rods, bearings, piston rings, timing chain and tensioner, oil pan and pickup, plug wires and my same old Mopar "race" electronic tach drive distributor. Those parts only had dyno time and survived without any damage so it was pointless to replace it all. I didn't re-hone the cylinders either so the rings were transferred directly to the new pistons in the same positions.
For this most recent dyno session, it was first run with the same OOTB Proform 850 from 2016. It eventually made the most power with the dyno shops' AED 950 cfm carb using 98 jets in the front and 99 in the rear. Turns out both of these carburetors were actually too small as the dyno showed well over 1" of vacuum under the throttle plate at WOT. BSFC was good though at .454 while using 288 lbs of fuel. The dyno has the Snuffleupagus tube but did not have a carb hat with an air sensor hooked up so no VE measurement but it's probably over 100%.
Timing is 20º initial and 34º total. I use an FBO advance limiter plate. It still has a slight curve for street driving but it's all in by around 1,500 rpm. I think it will probably want to idle at 1,200 or more. No timing comparisons were performed.
630hp @ 6,400 rpm and 567 lb. ft. of torque @ 5,200.
I'm a little scared of this thing now. It's going to be pretty rowdy on the street and will certainly be capable of low 10s in the 1/4 mile and may dip into the 9s if the driver can tune the thing and get it down the track at some point. Once in the car it will be using a Holley Terminator X system (which I believe is 950cfm). The hope is the EFI will help with drivability and consistency. It may not make quite the same peak power at WOT but it won't really be prone to weather changes and can theoretically be adjusted to run decently at low rpm. It has occurred to me that I might need a vacuum pump.
I do want to mention that going in I was concerned about using my brand-new TTI headers before knowing everything was good. They are expensive and TTI is very clear about running them on an unknown new engine. They tell you that if the coating gets discolored from a bad cylinder they won't warranty them. I brought my old step headers with me but the dyno operator assured me we would start conservatively and keep an eye on the A/F numbers before any real pulls were made. These larger headers are a royal PITA to get on even without being in the car so it really would have been a waste of time to start out with the smaller ones. The ports are round W2 style and are smaller than the head exhaust port anyway. In the end it turned out there was nothing to worry about as the A/F ratios were good from the start. We pulled the plugs after the last pull and they were literally perfect.
Note the timing mark at the base of the bend in the electrode. The shop owner looked at them with his loupe and said the carbon ring was perfect.
In any event, I am proud of what I built. A lot of time was spent on the details and the results of that speak for themselves. It seems like a pretty big accomplishment to have extracted this much power out of a standard LA combo on pump gas. OK, it's got a decent size solid roller cam in it and the heads are pretty special but none of it is exotic by any stretch - still has the stupid 59º lifter angle, no raised ports or offset rockers, no block fill, 2 bolt mains, I beam rods, flat top pistons with a standard ring pack, single 4 bbl cast intake with no plenum work... the same parts are available to everyone. With today's prices I still don't think I even have $10K in this combo.
Dyno sheet.
Turn it up! I left the comments in at the end because it meant a lot to me to hear them. The dyno shop owner is into some high dollar/top tier stuff so I don't take what he said lightly.
After we were done and breaking things down the dyno shop owner told me it would make 650 with an 1150 Dominator and a vacuum pump. I don't even know what to say about that.
I have to finish the car now so don't expect any any drag strip results until next year. I am bummed that another year has gone by with the car still not finished but the engine was a big step and things should fall into place a little easier now.
Enjoy folks!
I thought it would realistically make around 525hp. When I got to the dyno shop, the operator laughed and said yeah sure, we'll see. It ended up making 500 hp on the dot and 502 lb. ft. of torque. The dyno operator was genuinely surprised and impressed but I was disappointed that it didn't hit my number. There were a few things holding it back (not the heads or cam) and trying to understand how those choices impacted the results led me to revisit what I had done to that point. I opened my eyes to a a bunch of stuff so it was a good (but expensive) learning experience.
If you're inclined, the link below will provide some background on where this project started.
https://board.moparts.org/ubbthreads/ubbthreads.php/topics/2055372/re-416-on-the-dyno.html
BTW, @PRH was generous with his time back then in helping me understand what I was looking at in regards to the dyno results. I still appreciate that and carried some of his insight with me to now. The dyno shop owner was very surprised that I even knew what BSFC is and why it's important and commended me on that so thanks again Dwayne.
For various reasons, that first version of the engine never ran again so fast forward to 10.24.25. I won't detail all the boring crap that took place over the last 9 1/2 years but let's just say "I saw the light" during that time and this is what it looks like now;
Bloomer Performance aluminum cylinder heads with PAC springs and titanium retainers (and I believe Ferrea valves?) @BPE
Diamond flat top pistons for approx. 11.3:1 compression
Cometic .0039" MLS gasket
Bullet 263/268 @ .050" solid roller cam, .665" lift installed at 104 (they started me at 272 @ .050"!)
Comp 8043 lifters
Manton 5/16" pushrods (yes, 5/16")
Home port-matched Super Victor intake Super Victor port matching
Moroso electric water pump
TTI 1 7/8" headers
Precision HV oil pump
Left over from 2016 are the block, crank, rods, bearings, piston rings, timing chain and tensioner, oil pan and pickup, plug wires and my same old Mopar "race" electronic tach drive distributor. Those parts only had dyno time and survived without any damage so it was pointless to replace it all. I didn't re-hone the cylinders either so the rings were transferred directly to the new pistons in the same positions.
For this most recent dyno session, it was first run with the same OOTB Proform 850 from 2016. It eventually made the most power with the dyno shops' AED 950 cfm carb using 98 jets in the front and 99 in the rear. Turns out both of these carburetors were actually too small as the dyno showed well over 1" of vacuum under the throttle plate at WOT. BSFC was good though at .454 while using 288 lbs of fuel. The dyno has the Snuffleupagus tube but did not have a carb hat with an air sensor hooked up so no VE measurement but it's probably over 100%.
Timing is 20º initial and 34º total. I use an FBO advance limiter plate. It still has a slight curve for street driving but it's all in by around 1,500 rpm. I think it will probably want to idle at 1,200 or more. No timing comparisons were performed.
630hp @ 6,400 rpm and 567 lb. ft. of torque @ 5,200.
I'm a little scared of this thing now. It's going to be pretty rowdy on the street and will certainly be capable of low 10s in the 1/4 mile and may dip into the 9s if the driver can tune the thing and get it down the track at some point. Once in the car it will be using a Holley Terminator X system (which I believe is 950cfm). The hope is the EFI will help with drivability and consistency. It may not make quite the same peak power at WOT but it won't really be prone to weather changes and can theoretically be adjusted to run decently at low rpm. It has occurred to me that I might need a vacuum pump.
I do want to mention that going in I was concerned about using my brand-new TTI headers before knowing everything was good. They are expensive and TTI is very clear about running them on an unknown new engine. They tell you that if the coating gets discolored from a bad cylinder they won't warranty them. I brought my old step headers with me but the dyno operator assured me we would start conservatively and keep an eye on the A/F numbers before any real pulls were made. These larger headers are a royal PITA to get on even without being in the car so it really would have been a waste of time to start out with the smaller ones. The ports are round W2 style and are smaller than the head exhaust port anyway. In the end it turned out there was nothing to worry about as the A/F ratios were good from the start. We pulled the plugs after the last pull and they were literally perfect.
Note the timing mark at the base of the bend in the electrode. The shop owner looked at them with his loupe and said the carbon ring was perfect.
In any event, I am proud of what I built. A lot of time was spent on the details and the results of that speak for themselves. It seems like a pretty big accomplishment to have extracted this much power out of a standard LA combo on pump gas. OK, it's got a decent size solid roller cam in it and the heads are pretty special but none of it is exotic by any stretch - still has the stupid 59º lifter angle, no raised ports or offset rockers, no block fill, 2 bolt mains, I beam rods, flat top pistons with a standard ring pack, single 4 bbl cast intake with no plenum work... the same parts are available to everyone. With today's prices I still don't think I even have $10K in this combo.
Dyno sheet.
Turn it up! I left the comments in at the end because it meant a lot to me to hear them. The dyno shop owner is into some high dollar/top tier stuff so I don't take what he said lightly.
After we were done and breaking things down the dyno shop owner told me it would make 650 with an 1150 Dominator and a vacuum pump. I don't even know what to say about that.
I have to finish the car now so don't expect any any drag strip results until next year. I am bummed that another year has gone by with the car still not finished but the engine was a big step and things should fall into place a little easier now.
Enjoy folks!
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