E58 400 plus HP Dart sport build

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Wiki says Oklahoma is around 1200ft elevation.
10.7 is a good number for alloy heads....... with the right cam, like one with an Ica of around 60 degrees. Your cylinder pressure would come at around 178psi, not optimum but pretty close.
The Mutha-Thumpr SBM is spec'd at
287/305/107(probably at .006tappet), and 235/[email protected] lifts of .530/.515 with 1.6 arms, and they want it installed at 102.

If you do that, the ICA will be about 67* according to their spec numbers. This will drop your cylinder pressure down to around 167psi. Well you could almost run that with the iron heads. So then you have given up a pretty large amount of the advantage that those alloy heads offered.
Ideally you would want to run up around 185psi and I run there on 87E10. To get close to that with an Ica of 67*, you would need to increase the SCR to 11.5 for 183psi, and now yer talking!.
The difference between 167psi and 183psi is night and day in the midrange and especially at the lower end.
What I'm suggesting, is,
that you could probably run a cam about one to almost two sizes smaller on the street, depending on your local elevation, at the higher pressure, and not lose any zero to 60mph ET; and the bonus is that you could run a more street friendly convertor. Not to mention pick up a ton of fuel-economy.
You paid a lotta money for those alloy heads, and now with the Mutha, yer giving up a considerable amount of the benefits away, to get a sound? which comes from the very early opening exhaust event, and the exhaust-dilution on the overlap cycle....... which used to be called EGR; the very thing everybody loved to hate when it first came to the Mopar-world in the early 70s.
Ok, I get that the 235*cam is gonna make a lotta power.
But it's top end power.
If you run a street friendly say 3.73s, With a powerpeak around 5300, that would come at 52/71/103mph. Shifting at 6100 will be around; 48/82/117mph. Course this assumes the tires ain't spinning all the way. ...... and that will be the best trick. If you can't hook, yer 60ft alone will be well over 2 seconds. So what good is all the power gonna be if yer already a half a second behind a guy with half the motor, who did hook.
Here's what I'm saying: by my car's trapspeed of 93mph in the Eighth, it is making over 430 hp. In second gear (Manual trans and roadgear of 6.82) She will easily break traction at 50mph with BFG 295/50-15s. If it's already spinning, then it will keep right on spinning all the way thru Second, to 7200=85mph.
Ok I get that I can back out of the throttle and let the tires catch; but that would be missing the point. If I back out, I might as well just have less power in the first place. My Hughes HE3037AL cam specs at
276/286/110(@.008tappet) , 230/237 @.050, lifts of .549/.571 @1.6arms

This is about ONE size smaller than the Mutha, but without the Exhaust hoopla.
Here are the rest of the events, first the Comp with the advertised probably at .006 tappet rise ; then my Hughes3038 at .008 tappet rise, then my previous cam (HE2430AL) which was my favorite, especially when it ran at 11.3Scr/pumping over 190psi.
287int/114.5 compression/95.5extraction/305exhaust/82*o-lap/Ica of 67*
276int/ 114 compression /105 extraction/ 286exhaust/61* o-lap/Ica of 66*
270int/ 119 compression/108 extraction/276exhaust/53* o-lap/Ica of 61*
This last one (the HE2430AL) was BB strong in the bottom end, and even up the midrange. It was so strong that I traded some pressure for extraction, by retiming the cam and bolted on a double overdrive trans, geared for 65=1640rpm, and promptly got over 30mpgUSg. Yes and it too never got anything but 87E10.
But Ok, I get that you may be hooked on the Mutha's sound, but at what sacrifice?
And OK, I get that you might not care as much about being quick in the Zero to 60 arena. But I had to give it up, or put a buncha money into the suspension. Which would have made her a point and shoot kindof car. But I came to find out that I really liked sliding around corners near full steering lock. So then, I just learned to be "pretty good at it" as one cop said, as he handed me the ticket with a big smile on his handsome face. Then added; "but you can't be doing that here...." Sir-Yes Sir!.
Lol I'm old pretty small town I have already had visit by the police just checking it out. I won't get to crazy. But I do wanna run down to track just for fun not hung up on numbers at track. Just a starting point for now. Suspension will come later with some rear disc outback.
 
If you are NOT hung up on track numbers,
Then I very highly recommend to pump up the pressure, so you can run a more street-friendly combo.
Having run around 180psi already for 20 years, and up to 195 at one time, all on 87E10; I can tell you that this pressure is insanely addictive.

If you analyze how you actually operate your car,
>I'm pretty sure that WOT will only be a very small percentage of the time.
> a goodly amount of time will be spent idling or moving very slowly in first gear.
> but the vast majority of the time will be in Second gear at Part-Throttle traveling between 25 to 50mph or less. So, IMHO, this is the zone every streeter should be concentrating on.

To that end, running hi pressure, allows running lower-stalls and hi-way-friendly rear gears........ because the engine is making a chitload of low-rpm torque. This is saving you money at every gas fill-up.
>The Primary reason for running a hi-stall TC, is to allow the engine to spool up past the typical soft part of the power curve that exists in nearly every big-cammed small-block engine.
But alloy heads allow you to run higher pressures than do iron heads, so there is no reason, to run a high-stall on the street, if you take advantage of the pressure made possible, by the alloy heads.
>The Rear gears are used to move the power-window around in any speed range of interest.
> if your tires are spinning, you already have too much power... or rather, more than the tires can handle. Maybe that is what yur going for, I sure was, lol.
>The power required to run speed increases by the inverse proportion of the speed. So to run double a certain speed requires double x double the power. If it takes 40 hp to run 60 mph; then to run 120 will take 160; and to run 240 will take 640hp.
Obviously, 400hp is more than any of us ever need. The power in excess of that required to travel at a certain speed, goes to decreasing the time required to get up to that certain speed.
Now get this;
in the Eighth-Mile,
at 3400 pounds; 400 hp will get you about 92mph @as low as 7.5 seconds, whereas:
300hp will take about an additional 3/4 second, but be about 10 mph slower.
But again, that is using high-rpm power. On the street, you cannot go 92mph, nor even 82 except you risk getting a ticket. Now I'm not a cop and I don't care if you speed. But with street gears, and a 3-speed auto, your car will probably be shackled to way outside of it's power-window, from Third gear on. Lets say you shift at 6000. Going into Second the Rpm will drop to 3540 oops. Your Mutha will be gasping to get back on the pipe. With 3.23s, this will happen at about 55 mph. The Mutha will then struggle back up to say 3800 to find the bottom of the power curve, now at 59 mph. And then begins the march up to peak power at say, 5300/82mph. then over the top and down the backside of the now diminishing power-curve to say 6000@93mph. But to finish the quarter, you will have to shift. And when you do, 93mph will be ~4100 in Third, way off the power. Now shes gotta fight her way back up the power curve to finish at say 108mph@4800, still 500 short of the peak and wasting the 300 or so rpm, that come after that as well.
So the result of this is that your ET and mph are gonna belong to a less powerful engine.
Show me where stall helps in this.
Firstly, in first gear, because of tirespin, you will not be able to unleash all 400hp unless maybe you have a Super-Stock type suspension. So what good is a 3500 stall. And, lets say in First gear you average 300hp.
Then at the 1-2 shift, the Rs drop to 3540, so the 3500 is already pretty much hydraulically coupled at 1.1 ratio. So lets say in Second gear, your average power is 360. And lets say back to 350 on Third, cuz the engine never made it to 400; and it dropped in at 4100 so stall is history. Your delivered overall average power then is;
(300+360+350)/3 =337hp I made the numbers up but you get the idea.
Since you couldn't use all 400 in first gear, and never got to use all 400 in top gear, the only gear that was productive was Second.
So tell me again why I have 430hp.......
As a streeter, what I really want is a Second gear that when I nail it, has 400plus footpounds available, to instantly flash the tach into the rev-limiter, at 7200, with the tires screaming.
Ok hang on, 400ftlbs @3200 maths out to just 244hp
Case closed.
lol.
 
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Lol I'm old pretty small town I have already had visit by the police just checking it out. I won't get to crazy. But I do wanna run down to track just for fun not hung up on numbers at track. Just a starting point for now. Suspension will come later with some rear disc outback.
If you are NOT hung up on track numbers,
Then I very highly recommend to pump up the pressure, so you can run a more street-friendly combo.
Having run around 180psi already for 20 years, and up to 195 at one time, all on 87E10; I can tell you that this pressure is insanely addictive.

If you analyze how you actually operate your car,
>I'm pretty sure that WOT will only be a very small percentage of the time.
> a goodly amount of time will be spent idling or moving very slowly in first gear.
> but the vast majority of the time will be in Second gear at Part-Throttle traveling between 25 to 50mph or less. So, IMHO, this is the zone every streeter should be concentrating on.

To that end, running hi pressure, allows running lower-stalls and hi-way-friendly rear gears........ because the engine is making a chitload of low-rpm torque. This is saving you money at every gas fill-up.
>The Primary reason for running a hi-stall TC, is to allow the engine to spool up past the typical soft part of the power curve that exists in nearly every big-cammed small-block engine.
But alloy heads allow you to run higher pressures than do iron heads, so there is no reason, to run a high-stall on the street, if you take advantage of the pressure made possible, by the alloy heads.
>The Rear gears are used to move the power-window around in any speed range of interest.
> if your tires are spinning, you already have too much power... or rather, more than the tires can handle. Maybe that is what yur going for, I sure was, lol.
>The power required to run speed increases by the inverse proportion of the speed. So to run double a certain speed requires double x double the power. If it takes 40 hp to run 60 mph; then to run 120 will take 160; and to run 240 will take 640hp.
Obviously, 400hp is more than any of us ever need. The power in excess of that required to travel at a certain speed, goes to decreasing the time required to get up to that certain speed.
Now get this;
in the Eighth-Mile,
at 3400 pounds; 400 hp will get you about 92mph @as low as 7.5 seconds, whereas:
300hp will take about an additional 3/4 second, but be about 10 mph slower.
But again, that is using high-rpm power. On the street, you cannot go 92mph, nor even 82 except you risk getting a ticket. Now I'm not a cop and I don't care if you speed. But with street gears, and a 3-speed auto, your car will probably be shackled to way outside of it's power-window, from Third gear on. Lets say you shift at 6000. Going into Second the Rpm will drop to 3540 oops. Your Mutha will be gasping to get back on the pipe. With 3.23s, this will happen at about 55 mph. The Mutha will then struggle back up to say 3800 to find the bottom of the power curve, now at 59 mph. And then begins the march up to peak power at say, 5300/82mph. then over the top and down the backside of the now diminishing power-curve to say 6000@93mph. But to finish the quarter, you will have to shift. And when you do, 93mph will be ~4100 in Third, way off the power. Now shes gotta fight her way back up the power curve to finish at say 108mph@4800, still 500 short of the peak and wasting the 300 or so rpm, that come after that as well.
So the result of this is that your ET and mph are gonna belong to a less powerful engine.
Show me where stall helps in this.
Firstly, in first gear, because of tirespin, you will not be able to unleash all 400hp unless maybe you have a Super-Stock type suspension. So what good is a 3500 stall. And, lets say in First gear you average 300hp.
Then at the 1-2 shift, the Rs drop to 3540, so the 3500 is already pretty much hydraulically coupled at 1.1 ratio. So lets say in Second gear, your average power is 360. And lets say back to 350 on Third, cuz the engine never made it to 400; and it dropped in at 4100 so stall is history. Your delivered overall average power then is;
(300+360+350)/3 =337hp I made the numbers up but you get the idea.
Since you couldn't use all 400 in first gear, and never got to use all 400 in top gear, the only gear that was productive was Second.
So tell me again why I have 430hp.......
As a streeter, what I really want is a Second gear that when I nail it, has 400plus footpounds available, to instantly flash the tach into the rev-limiter, at 7200, with the tires screaming.
Ok hang on, 400ftlbs @3200 maths out to just 244hp
Case closed.
lol.
So what if I jump up more compression via the piston itself if I have clearance I can get away with another point say these KB190
 
Let first figure out what head you want to run and then run some numbers on a couple of different pistons and head gasket combo’s.
 
Let first figure out what head you want to run and then run some numbers on a couple of different pistons and head gasket combo’s.
The heads are purchased the cam is also purchased so that's all in already.
COMP Cams K20-602-4 COMP Cams Thumpr Hydraulic Flat Tappet Cam and Lifter Kits | Summit Racing Mopar Chrysler SB 318 360 170cc 65cc Hydraulic Roller Assembled Cylinder Heads purchased carburetor is a pro-form 850 Holley 4150 quick fuel style. Intake is a Mopar Chrysler Dodge SB 318 340 360 MidRise Air Intake Manifold Machine Polished. Also have a 1.6 ratio roller rocker assembly brand new from speed master. I have not purchased the gasket set, pistons and bearings yet and freeze plugs.
 
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My bad! Sorry.

If it were I, I’d use a flat top at zero deck. Like a KB-107 or similar. Also a .039 head gasket. That’ll work great with the aluminum heads and pump gas with that cam.
 
My bad! Sorry.

If it were I, I’d use a flat top at zero deck. Like a KB-107 or similar. Also a .039 head gasket. That’ll work great with the aluminum heads and pump gas with that cam.
And that was my plan all along it's right on the edge 10.5 and 10.7 with 93 octane.other option or these pistons DODGE Speed Pro H116CP 30 Speed-Pro Hypereutectic Pistons | Summit Racing. I do appreciate all jumping in on this why I made the thread it's a great learning experience what I thought I knew. What I now understand more so. I'm in good shape for what I wanted is my conclusion.
 
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I used those very slugs in the wife’s .030-360.

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All my parts of except pistons are dropped off now. Hopefully week or two get my go ahead to order pistons I think my order the 30 over it was a running engine with no issues. Hopefully I don't regret that.
 
This is what happens, top photo. The fix is to just RTV all but one of the slots in the second photo. Problem solved. Toss in Petronix module and coil... rock-n-roll.

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Silly question on this HEI I got it with the intention of replacing module and coil with this. What I read it says it does including question answered by a team performance is that correct? Kept reading answered my own question sort of it will get ballast out ECU and coil. i would love to see more info on pulling this wiring out. I hate this as that's a new engine harness but it's better than that 50 year old crap for sure.
 
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Silly question on this HEI I got it with the intention of replacing module and coil with this. What I read it says it does including question answered by a team performance is that correct?
I'm trying to figure out the voltage regulator is it ok with those leads going to ignition box and ballast removed. Plus I got coil wires that will go and so on like you said. So now looking at wiring diagram figuring this out.
 
On the engine front was told they are getting it all cleaned up. He wants to check before I order pistons I'm pissed I should have just ordered them missed all the sales will get shafted on price now. I may just go ahead and pull trigger on my 30 over hell of the block is that bad I may replace see no issue with that compression checks were great and even. Only bad part was lack of oil changes as seen by distributor and Cam when I took a peak inside it.
 
Little stuck on piston choice I dont want a hyperkinetic piston now. Builders really hate on them for breaking and I'm concerned as they were pretty vocal and it was multiple folks. I know a lot here use them but I'm going to error on caution regarding my kb107 and not buy. I need a stock weight piston forged if possible flattop valve relief. The ones I have seen look like I will have to rebalance and do a new converter and such for the combo. It's also about the fact it's my motor and I want to do it my way my choices if that makes any sense. Any suggestions on the piston choice still waiting to hear back on overbore and how much I may have to go.
From what I've read, a big reason people have problems with the KB hypers is they don't follow KB's requirements for ring gap. If you don't follow KB's recommendation, the top ring ends will but when the engine gets hot, the ring sticks in the bore, and then bang the top land on the piston breaks. Set the ring gap to what KB says and you shouldn't have any problems. That said, a nice set of Mahle's with rings is only about $100 more than a set of the KB 107's and a set of Total Seal gapless...
As for balancing, it's about $300 which might sound like a lot but isn't really a lot considering how much you pobably already have in the engine.
 
Silly question on this HEI I got it with the intention of replacing module and coil with this. What I read it says it does including question answered by a team performance is that correct? Kept reading answered my own question sort of it will get ballast out ECU and coil. i would love to see more info on pulling this wiring out. I hate this as that's a new engine harness but it's better than that 50 year old crap for sure.
I did not remove the old wiring. I bypassed the ballast resistor and used that for the hot to the new dizzy. The rest I just tucked back into the plastic wire loom just in case I ever decided to go back to OEM.
 
I did not remove the old wiring. I bypassed the ballast resistor and used that for the hot to the new dizzy. The rest I just tucked back into the plastic wire loom just in case I ever decided to go back to OEM.
Ok that's why I got the backup plan orange Mopar ECU so just tape hide the unused coil/balast/ECU for later and in the loom. The yellow blue wire Im guessing is the one you tapped into, looking at your photos here.
 
Ok that's why I got the backup plan orange Mopar ECU so just tape hide the unused coil/balast/ECU for later and in the loom. The yellow blue wire Im guessing is the one you tapped into, looking at your photos here.
If I recall correctly I had a brown going into the ballast and a blue coming out. Regardless.. whichever gives the 12v ignition on (after bypassing the ballast) is the one I used.
 
Talked to builder going to get some pictures today. Number 3 cylinder was marginal may have to vote more than .30 over. They got it soaking in the vat cleaning up then will throw the bore bar on it see where we're at.
 
Dropping pistons off KB 107 30 over Monday will talk to him about decking block I'm not doing zero deck but I am going to get a bit more pressure and of course I want the block straight as well. He is afraid a bit because its close to 11 to 1. I should without decking be at 10.5 to 1 with a .039 felpro head gasket. So I got little to play with. Run premium no ethanol anyways. Have to make sure timing is dead on is the plan here.
 
What octane is available to you in OK?
 
I’m used to the 93/10% ethanol. It’ll work for your non ethanol 93.
 
Gotta come up with a wiring plan and get this sorted out as engine is coming along quickly now. Hopefully I can get the new ignition switch in tonight and comb over this Ron Francis kit see where I'm at. It's a lot hopefully I have not bitten off to much for spring and some fun!
 
I wouldn't push the compression on a KB piston...they reflect heat back at the chamber, so 9.5:1 acts more like 9.8-9.9:1 compression...
 
Ok so I thought Clevite bearings were good. Builder has been having issues with them not fitting right. He is unhappy with clearance on them. Hopefully get past this sillyness as car is literally ready to go waiting on the heart. New set is ordered so we can move along.
 
93 octane all around us no ethanol easy to find Phillips stations.
If you are going to drive the car regularly, I highly recommend you DO use 10% ethanol super. It has better octane properties and better detonation resistance. As long as you don't sit it up for long periods, it will not hurt a thing.
 
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