416" on the dyno

[rumblefish360]

Assuming your like me and could care less what torque and power I am making anywhere below where the convertor hits at, what is your suggestion?

It’s amazing how many people miss this about a drag car or even a serious street strip machine. Then they cry and complain about a loss of torque with a big cam and crap idle.

The best thing I found for low end street torque are things I have spoken about and become largely ignored and balked about but seemed of the knowledge won’t do it and just continue to cry about.

I’m surprised that you, yourself ask this question as one of the more knowledgeable people here. You already know about the balance of a build in an engine couple with the drive train plus the size and weight of the car and its suspension mods that may be needed.

 

[B3422w5]

It’s amazing how many people miss this about a drag car or even a serious street strip machine. Then they cry and complain about a loss of torque with a big cam and crap idle.

The best thing I found for low end street torque are things I have spoken about and become largely ignored and balked about but seemed of the knowledge won’t do it and just continue to cry about.

I’m surprised that you, yourself ask this question as one of the more knowledgeable people here. You already know about the balance of a build in an engine couple with the drive train plus the size and weight of the car and its suspension mods that may be needed.

I get all that. All I care about is how it runs between 5k and 6600 or so.
At lower rpm’s on the street I don’t really care because it makes plenty enough power to putt around because I keep my foot out of it on the street except for an occasional blip to clean it up.
Plugs last me a couple seasons, and I am fine with it idling at 1200 or so, keeps those solid lifters spinning, keeps the one wire alt excited so it’s putting out.
So my needs and expectations are probably different than most.
Meanwhile, I can tool around at 2800-3200 rpm cruising without issue.

 

[rumblefish360]

I get all that. All I care about is how it runs between 5k and 6600 or so.
At lower rpm’s on the street I don’t really care because it makes plenty enough power to putt around because I keep my foot out of it on the street except for an occasional blip to clean it up.
Plugs last me a couple seasons, and I am fine with it idling at 1200 or so, keeps those solid lifters spinning, keeps the one wire alt excited so it’s putting out.
So my needs and expectations are probably different than most.
Meanwhile, I can tool around at 2800-3200 rpm cruising without issue.

One word for this:

SWEEEEEEEEEEEEEEEEEET!!!

 

[B3422w5]

Some very sharp guys posted in this thread about locked out stuff

https://board.moparts.org/ubbthread.../drag-race-msd-distributor-locked-or-not.html

 

[Newbomb Turk]

Assuming your like me and could care less what torque and power I am making anywhere below where the convertor hits at, what is your suggestion?

Ive answered this before.

There isn’t an engine that needs the same timing at peak torque as it does at peak power. That’s the fact.

You drive it up the return road dont you? The correct timing curve keeps the plugs clean.

It’s pretty basic. And engine usually wants 1.5-2 degrees of advance per 1k rpm. Do you data log your runs to see what the rpm is on fallback? If not you are guess.

If you haven’t bench tested your ignition you have no clue what your timing is.

But you will continue to argue like a shoe polish tuner.

Do what you want. You still dont control physics. And a bunch of men smarter than both of us put together figured this **** out long ago.

 

[Newbomb Turk]

Some very sharp guys posted in this thread about locked out stuff

https://board.moparts.org/ubbthread.../drag-race-msd-distributor-locked-or-not.html

Ive probably read it.

Just because someone does something doesnt mean its correct.

Again, you argue like you are something other than a shoe polish tuner. You struggle with using a timing light, but you want to be right.

You’re right. Lock it out. It’s what all the fast guys do.

 

[rmchrgr]

Good job. Now if these numbers were the goal, the heads were the problem ...you removed them and stuck some way bigger better flowing heads on.. like night and day.
You could probably squeeze a little more out of those rhs, but you were already knocking on the door of running out of port volume.
Jmo.

Thanks. I'll agree with what you said to an extent but there were a number of factors that prevented that first version from making the power I hoped it would and it wasn't the heads. I didn't only change the heads for round two, the whole thing is different now. Regardless, if you go by the adage that says power = double the head flow then the IMM-RHS heads should support at least 600hp.

As I said in my first post, the goal 10 years ago with the RHS heads was 525hp. I would have done cartwheels if it made that. In reality there wasn't a huge difference between my stated goal and what it actually made but it was enough to make me want to go back and improve on it. I would have liked to have had some seat time with that version of the motor but it just wasn't meant to be.

The exhaust ports on the RHS heads were essentially untouched so figure the BPEs likely flow more on that side. I'm not sure if there is even room for a larger exhaust valve on the RHS heads. Maybe Brian will chime in here and let us know if that's the case but it's not terribly relevant to this thread. Either way, the RHS are good heads especially with the IMM CNC program - he had them flowing 293 CFM. They weigh about 800lbs each though so switching to aluminum castings shaved a bunch of weight off the front and up high. Trust me, that was not a small part of the decision to go with aluminum.

The intake port openings on the BPEs are larger than any head I've ever laid eyes on so that might account for something but I honestly don't know what they flow. Far as I can tell, Rod does not publish that info because it just creates unnecessary B.S.. It's not always about the biggest number anyway.

The pushrod pinch area is where the BPEs shine because they essentially have no pinch at all. The pinch is the Achilles heel of any standard-port LA head and is why the factory created the W stuff. If you think about it from that perspective, the BPEs are kind of the best of both worlds - basically no pushrod pinch yet no need for offset rocker gear.

All anyone needs to know is that the BPEs are very efficient and will obviously support well over 600hp. IMO they are the current pinnacle of standard LA stuff. If you want or need to make more power with a small block you're looking at much more expensive parts.

Maybe someone will crack 700 or more with a set of BPEs but that's going to take compression, a tricked out intake, big roller cam, 2 1/4" headers and an 1,150 Dominator. Race motor stuff.

 

[MOPAROFFICIAL]

Thanks. I'll agree with what you said to an extent but there were a number of factors that prevented that first version from making the power I hoped it would and it wasn't the heads. I didn't only change the heads for round two, the whole thing is different now. Regardless, if you go by the adage that says power = double the head flow then the IMM-RHS heads should support at least 600hp.

As I said in my first post, the goal 10 years ago with the RHS heads was 525hp. I would have done cartwheels if it made that. In reality there wasn't a huge difference between my stated goal and what it actually made but it was enough to make me want to go back and improve on it. I would have liked to have had some seat time with that version of the motor but it just wasn't meant to be.

The exhaust ports on the RHS heads were essentially untouched so figure the BPEs likely flow more on that side. I'm not sure if there is even room for a larger exhaust valve on the RHS heads. Maybe Brian will chime in here and let us know if that's the case but it's not terribly relevant to this thread. Either way, the RHS are good heads especially with the IMM CNC program - he had them flowing 293 CFM. They weigh about 800lbs each though so switching to aluminum castings shaved a bunch of weight off the front and up high. Trust me, that was not a small part of the decision to go with aluminum.

The intake port openings on the BPEs are larger than any head I've ever laid eyes on so that might account for something but I honestly don't know what they flow. Far as I can tell, Rod does not publish that info because it just creates unnecessary B.S.. It's not always about the biggest number anyway.

The pushrod pinch area is where the BPEs shine because they essentially have no pinch at all. The pinch is the Achilles heel of any standard-port LA head and is why the factory created the W stuff. If you think about it from that perspective, the BPEs are kind of the best of both worlds - basically no pushrod pinch yet no need for offset rocker gear.

All anyone needs to know is that the BPEs are very efficient and will obviously support well over 600hp. IMO they are the current pinnacle of standard LA stuff. If you want or need to make more power with a small block you're looking at much more expensive parts.

Maybe someone will crack 700 or more with a set of BPEs but that's going to take compression, a tricked out intake, big roller cam, 2 1/4" headers and an 1,150 Dominator. Race motor stuff.

Its not knock on anyone or the rhs heads themselves other than its not an ideal head when you want to make 550+ in my book and I've them perform and make over 550 but the cams required aren't very friendly.

 

[rmchrgr]

That made good power. You should be proud of that for a home build. There’s not many similar. It’s relatively efficient also.

Thank you.

Interesting to me how hot you ran it on the dyno and one thing I don’t like is the oil pressure. Any concern there?

Seems to be right where it should be, no? It's a HV pump that has the opening in the pump body enlarged and smoothed. I did the same thing to the suction side on the main cap.

 

[rmchrgr]

Its not knock on anyone or the rest heads themselves other than its not an ideal head when you want to make 550+

Respectfully, I will disagree. I think the RHS heads are definitely capable of supporting 550hp. Most people don't choose them for that level of power because they were marketed as iron replacement type heads. They're long gone now anyway so even finding an unmodified set now would be a little tough. Not sure how many sets IMM sold but it couldn't have been that many.

293 cfm of intake air flow is no joke.

 

[rmchrgr]

I get all that. All I care about is how it runs between 5k and 6600 or so.
At lower rpm’s on the street I don’t really care because it makes plenty enough power to putt around because I keep my foot out of it on the street except for an occasional blip to clean it up.
Plugs last me a couple seasons, and I am fine with it idling at 1200 or so, keeps those solid lifters spinning, keeps the one wire alt excited so it’s putting out.
So my needs and expectations are probably different than most.
Meanwhile, I can tool around at 2800-3200 rpm cruising without issue.

I'm basically in the same boat as Don. Street machines are always a challenge but that's why we do this kind of stuff.

These low rpm scenarios are precisely why I use EFI. If I can keep it from fouling plugs every time I take out of the garage then it'll be a full win.

 

[4spdragtop]

Congrats Joe and thanks for sharing!
At the risk of sounding stupid, what's the liquid at the end of the dyno run? Im assuming water?
You know you done GOOD by the comments of the dyno operator.
Kudos!

 

[rmchrgr]

Congrats Joe and thanks for sharing!
At the risk of sounding stupid, what's the liquid at the end of the dyno run? Im assuming water?
You know you done GOOD by the comments of the dyno operator.
Kudos!

Thanks but Joe? I'm Greg.

Yes, the drips are just water. Probably an imperfect hose connection. The electric water pump has a threaded port for AN-type fittings which I will be using when it goes in the car.

 

[4spdragtop]

Oops my bad, sorry Greg. I figured water as you and dyno guy weren't concerned.
Apologies and congrats.

Thanks but Joe? I'm Greg.

Yes, the drips are just water. Probably an imperfect hose connection. The electric water pump has a threaded port for AN-type fittings which I will be using when it goes in the car.

 

[rmchrgr]

Oops my bad, sorry Greg. I figured water as you and dyno guy weren't concerned.
Apologies and congrats.

All good, thank you for the kind words.

 

[Just Send It]

Very nice! Excellent numbers.

I cannot wait to get a set of those heads and a SR cam. Game changer.

 

[TT5.9mag]

Seems to be right where it should be, no? It's a HV pump that has the opening in the pump body enlarged and smoothed. I did the same thing to the suction side on the main cap.

While I dont think it’s a problem per se, I do like to see a little more pressure than that. My concern should not be your concern which is why I asked. If the builder has the clearances where he wants them, and is happy with the pressure then that’s what matters.

 

[rmchrgr]

While I dont think it’s a problem per se, I do like to see a little more pressure than that. My concern should not be your concern which is why I asked. If the builder has the clearances where he wants them, and is happy with the pressure then that’s what matters.

There's no issue for me. At peak power rpm it's 63.7lbs. If you go by the 100psi for every 1K of rpm oil pressure rule it's right where it should be. It does drop a few pounds at 6,500 but it's not like it suddenly goes to zero. I already planned to program a low-pressure shut off into the EFI software for a little insurance.

I chose the HV pump for the street. I suppose there are pros and cons to them. I'd have to look through my documents from 2015 to see what the exact clearances were but from what I remember, they're standard for a street/strip application and nothing is loose. Perhaps if I changed to a standard volume pump it might net a few more psi or even a few more HP but the HV is staying. Is what it is.

 

[MOPAROFFICIAL]

There's no issue for me. At peak power rpm it's 63.7lbs. If you go by the 100psi for every 1K of rpm oil pressure rule it's right where it should be. It does drop a few pounds at 6,500 but it's not like it suddenly goes to zero. I already planned to program a low-pressure shut off into the EFI software for a little insurance.

I chose the HV pump for the street. I suppose there are pros and cons to them. I'd have to look through my documents from 2015 to see what the exact clearances were but from what I remember, they're standard for a street/strip application and nothing is loose. Perhaps if I changed to a standard volume pump it might net a few more psi or even a few more HP but the HV is staying. Is what it is.

Just a typo im sure. 10 psi for every 1000 rpm and f1 says less, like 7 psi.. but i like to see more like 10 psi and I don't like less than 25psi at idle. High psi spring fixes that, so 7000 rpm would actually see 70+ psi and hold a higher idle oil pressure.

 

[B3422w5]

Ive probably read it.

Just because someone does something doesnt mean its correct.

Again, you argue like you are something other than a shoe polish tuner. You struggle with using a timing light, but you want to be right.

You’re right. Lock it out. It’s what all the fast guys do.

I am not saying what you are pointing out doesn’t have merit. No reason to get snarky.
Lots of very, very sharp guys who I respect a lot and race with were in that thread. I think you were too, actually..lol.

 

[Newbomb Turk]

I am not saying what you are pointing out doesn’t have merit. No reason to get snarky.
Lots of very, very sharp guys who I respect a lot and race with were in that thread. I think you were too, actually..lol.

I was. And I said the same thing there.

I’ll ask you a serious question.

What is your timing at 2500, 3500, 4500, 5500 and 6500?

And especially if you drive them in the street they need a curve.

If it’s a bracket car and IF it’s a power glide and if the converter is 1k plus above peak torque and the fall back rpm is 1200ish rpm then locking out the timing is plausible.

I know for a fact that fast cars (class racing not shoe polish racing), especially with 4 or 5 gears are running different timing curves for every single gear.

So even the best curve won’t be the best curve for every gear.

I’m seriously looking at buying a programmable ignition but I can only tolerate MSD and I want to see if I can do 12:1 on pump gas with weights, springs AND a vacuum advance.

I know I can do it without the VA, but my mentor says if I play with it on the dyno enough I can do it.

So we will see. If I can’t I’ll have to plug the VA or do the programmable deal but with that I will need a crank trigger because…go big or go home.

So where is your timing at those rpm?

 

[B3422w5]

I was. And I said the same thing there.

I’ll ask you a serious question.

What is your timing at 2500, 3500, 4500, 5500 and 6500?

And especially if you drive them in the street they need a curve.

If it’s a bracket car and IF it’s a power glide and if the converter is 1k plus above peak torque and the fall back rpm is 1200ish rpm then locking out the timing is plausible.

I know for a fact that fast cars (class racing not shoe polish racing), especially with 4 or 5 gears are running different timing curves for every single gear.

So even the best curve won’t be the best curve for every gear.

I’m seriously looking at buying a programmable ignition but I can only tolerate MSD and I want to see if I can do 12:1 on pump gas with weights, springs AND a vacuum advance.

I know I can do it without the VA, but my mentor says if I play with it on the dyno enough I can do it.

So we will see. If I can’t I’ll have to plug the VA or do the programmable deal but with that I will need a crank trigger because…go big or go home.

So where is your timing at those rpm?

I have no idea, I check it at 3k and idle.

 

[rmchrgr]

Just a typo im sure. 10 psi for every 1000 rpm and f1 says less, like 7 psi.. but i like to see more like 10 psi and I don't like less than 25psi at idle. High psi spring fixes that, so 7000 rpm would actually see 70+ psi and hold a higher idle oil pressure.

Yes, sorry 10 psi/1,000 rpm. I can always put in a different spring or experiment with a lighter weight oil than 10w30.

My last car with a standard volume oil pump (BB) idled at 20-22psi hot with 10w30. Every once in a while I’d catch a glimpse of the gauge and it would surprise me but then I’d remember oh, yeah that’s what it does, it’s fine.

This engine will idle around 1,200 so it probably won’t go much below 25psi hot. Not sure where it will shift at yet.

 

[Newbomb Turk]

I have no idea, I check it at 3k and idle.

That is the correct answer. And sadly, you’d be in the majority of racers today. None of them have any idea what their timing is at any point in the curve except where they set it and check it.


Im betting (guessing actually) that you are using an MSD 6 box. Probably analog, not that the digital boxes are any better and that somewhere between 3500 and 4500 rpm the timing starts retarding.

How many degrees and how much more it retards is also a guess unless you bench test it.

You can see it for yourself with a timing light, but ALL timing lights also have a slew rate and they don’t all have the same slew rate.

So even if I set the timing curve on my bench I know the actual timing numbers will be slightly different at the crank on the engine because the timing light is slower than the electronics on my test bench.

Generally, the better the timing light the closer it is to my machine. I’ve seen timing lights off 4 degrees at 1k rpm.

As long as you know it and you always use the same timing light you can tune with it.

One thing that drives me crazy is guys show up to dyno their engine and they don’t bring their timing light. It just makes **** all the harder once it’s in the car.

Or worse yet, you get to the track and they want to make a timing change (which Im all for if the conditions call for it) and they borrow a timing light.

 

[rmchrgr]

I know for a fact that fast cars (class racing not shoe polish racing), especially with 4 or 5 gears are running different timing curves for every single gear.

OK, how is that even possible? I create my own timing tables in the Holley software and unless I am missing something I don’t see how you would accomplish that. I would genuinely like to know.

Regardless, how much different could the individual curves be? You’re only dropping a few hundred rpm between them.

On the dyno we checked the timing at 3,000rpm and it was 34. The Holley EFI software has a check sequence to verify the timing at any RPM you want.