Leaving Power on the Table, 440

[6872n73]

Fuel injection has a hard time auto tuning at less than 110lsa
What is your fuel pressure at 5700

 

[BSB67]

So I have been looking at my combo and thinking about getting a new cam with a bit more duration but was wondering if that is my bottleneck for more power. Not too woried about street manners and would like something a bit more lumpy at idle. I do intend to race a bit at the track in Roswell, which is 3573 elevation.

Here is what I currently have...
440 block, .040" over, stock stroke
Forged crank
KB 237 pistons zero deck
FelPro head gaskets .039" compressed
Stealth Heads, CNC ported (Intake 311cfm @.550 lift / exhaust 210cfm @ .550" lift)
Hughes 1.5 Rocker arms
Holley Sniper EFI 550 (650 max HP)
Holley Street Dominator single plane intake
1 7/8" long tube headers into 2.5" exhaust
Pertronix Ignitor III
Cam - Hughes STL3842BS solid lifter, 105* centerline, Duration at .050" 238* / 242*, Lift .558" I / .564" E
PTC 9.5" torque converter
3.55 rear end ratio on 275/65 R15 tires

Air in, air out right? I like the cam but the engine seems to top out a little over 5700 rpms, which is where the cam power band ends. I was thinking a similar cam with more duration to bump the power up into the 5900 - 6000 rpm range. Car has plenty of power down low as it sits. But am I hitting a road block with the intake or the headers or even the heads?

Best 1/4 and E.T at 3573 elevation was a 13.15 @ 106.81

Looking at the Hughes STL4650BS, centerline 104*, duration at .050" 246* / 250*, Lift .576 I / .588" E. I would be able to keep my springs as the specs are identical as to pressure. And I want to stay with solid lifter. I'm not interested in going roller.

Thanks!

What a fun thread 3wood!

A couple questions. What exactly was the DA when you ran the 13.15 @ 106. Was it the 4400’? What was the 60’? Better yet, can you post the et slip?

For me, step one is confirming that what it runs now is reasonable for the combination of parts that you have. Your parts selection sound like a good combo to me, but is it running the numbers it should?

 

[threewood]

What a fun thread 3wood!

A couple questions. What exactly was the DA when you ran the 13.15 @ 106. Was it the 4400’? What was the 60’? Better yet, can you post the et slip?

For me, step one is confirming that what it runs now is reasonable for the combination of parts that you have. Your parts selection sound like a good combo to me, but is it running the numbers it should?

There is room for improvement at the light so I believe it can run high 12's with good traction and reaction.

 

[RemCharger]

View attachment 1471802View attachment 1471803
There is room for improvement at the light so I believe it can run high 12's with good traction and reaction.

Your reaction times are a little rough, but have no connection to your et. Try leaving right on the last yellow.
The 60 fts are all traction (try borrowing some slicks?) And carb tuning and tq converter selection. But all in all pretty good times.

 

[Budnicks]

A **gear change to steeper gears
(3.73:1, 3.91:1, 4.10:1, 4.30:1 etc.)
especially at altitudes
(RAD/corrected elevations is rarely what the real altitude is,
RAD it's usually always far higher)
IT will/can make a huge difference too,
& it's far easier to move a heavy car, with steeper gearing
it may make it a lil' less freeway/hwy friendly,
but great from stoplight to stoplight
(go to a slightly taller/stickier tires, will help)
but;
It will perform way better, across the rpm band,
especially if you can get it hooked
A lot of it, a dual purpose car, Street/Strip & performs well at both
(that's what God made N2O for )
it really comes down to & depends on what you can put up with,
neg. in one realm or the other
anything you sacrifice in one, hurts it somewhere in the other
It's really hard to have "your cake & eat it too",
to have perfect/friendly street manors & great performance at the track,
in both these realms

just because you can make more HP at WOT
a dyno isn't like driving a car, far more at play to street driving manors
needs to be considered

**get better tires & more traction, for the purpose to be used
if you really want to make improvements in ET
& a bigger diameter/taller tire, will have better/more ground contact patch

**exhaust cut-outs (manual or electric) & dumps like 12"-18" downstream
somewhere after your O2 sensors, you can reduce the size after that point
after the cut-outs, it will help if it's tuned for it
or the EFI can compensate for it,
then most the more restrictive exhaust/pipe size can be left alone

*intake/induction suited for your intended purpose
(or EFI nozzle/TB sizes & computer tuning)

**looser converter down low, that doesn't give up as much (slipping) in high gear
converters are really dependent on rear gearing, proper selection is key
& can make or break a combo with any street/strip car
& the camshaft, where it truly makes peak torque (to move you)
& WOT power (to get MPH, in the traps)
maybe have yours reworked

*It's not always the lack of horsepower, that harbors making good ETs
for what you got, the car's set-up do thou
HP is MPH
ET is the combo of the car & Torque to get off the line, move the car quickly

*it's "always" how you put it down to the track & how the car's combo works

**maybe also a thinner head gasket, will give you more compression too
(if you have the proper piston-to-valve & valve spring clearances)
altitude wants more
more advanced timing usually too

*any of the above will be way better at 60' times & that's really where
you can make up a shitload of ET, in the 1st 330'
a 1/10 improvement in 60', is like 3-4/10s in the 1/4 mile
without spending a small fortune

*suspension & good shocks is another subject 'all together'
that needs to be addressed too

Another easy band-aide even,
**go to 1.6:1 rockers (over the current 1.5:1)
will give you 10% more lift, more breathing
& a few %'s of degree's slightly more duration too,
both the in/ex valves, both will be staying open longer too
(that's if you have the proper piston-to-valve & valve spring clearances)
can go from the 0.558"in/0.564"ex GVL 'minus your valve lash'
(you're probably looking at currently 0.540"/0.545" ranges in reality)
to *0.595"in/0.597"ex gross valve lifts
(obviously, it's less with the #s in valve lash)


*EFI likes/will like a 110*-112* lsa better too
the EFI may be your limitation or choke point too, running out of fuel
or have the wrong fuel map, at the wrong time
FastmanEFI Richard Nedball is a member here, may want to talk to him

* just some options & my opinions
** better options, opinions will vary as vastly as the posts

all of it depends on how much you can cope with, and still be streetable
& how much you want to spend

good luck

 

[fourgearsavoy]

I was looking at Howard's cams when I went with a SFT and bought one that was a little too much for what I was doing. It lost a bunch of low end power under 3000. I looked at another SFT that was a little more tame but I found a street roller to fit my needs.
This sounds like what would fit your needs.

Howards Cams, Mechanical Flat Tappet Camshaft, Chrysler BB B/RB, 254/260 @ .050, .550/.555, 108 LS - Competition Products

Howards Cams Mechanical Flat Tappet Camshaft Chrysler BB/RB, 383-440, 254/260, 289/295, .550/.555, 108+4, .022/.022 All Howards cams use the highest-grade quality cores available. Computer designed with knowledge of over 65 years of performance and racing camshaft manufacturing. Howards cams...

www.competitionproducts.com

 

[33 IMP]

No offense meant (ever notice that whenever someone says that, the next thing they say is offensive? ) but your 60ft is horrible. With your presumed power, converter and gear, I would hope for a 1.75 and expect low 1.8s. Pick up .2 in the 60, that's at least .3 in the eighth, and probably .4 or more in the quarter. Boom, 12.70s.
Slicks would be my step one. Way,WAY before a cam swap.
Edit: and as said above, reaction time has NO bearing on e.t. (or speed). Sit at a green lite for ten seconds with a twelve second car, then make a pass, and you will have a 12 second e.t....... and a 10 1/2 second reaction time.

 

[33 IMP]

Have you determined what your actual stall speed is? A PTC 9.5 should be a good piece.
And what is your starting line technique? Stab it from idle, full throttle to stall against the brakes, bring it to 2500 and stab it? It makes a difference, especially with poor starting line traction.

 

[Curiousyellow71]

It can be hard to get traction at a event w a bunch of street tires making passes. It can be a skating rink. We always struggled to lift the front wheels playing at a street race. Prepped track...no problem!

 

[threewood]

No offense meant (ever notice that whenever someone says that, the next thing they say is offensive? ) but your 60ft is horrible. With your presumed power, converter and gear, I would hope for a 1.75 and expect low 1.8s. Pick up .2 in the 60, that's at least .3 in the eighth, and probably .4 or more in the quarter. Boom, 12.70s.
Slicks would be my step one. Way,WAY before a cam swap.
Edit: and as said above, reaction time has NO bearing on e.t. (or speed). Sit at a green lite for ten seconds with a twelve second car, then make a pass, and you will have a 12 second e.t....... and a 10 1/2 second reaction time.

No offense. I know I suck. I use the footbrake technique. Try to leave at the last yellow. If I stab it wot the tires spin so I go 3/4 until I get off the line. I need to experiment with my burnout with the MT E/T tires. I take it to about 3k but I have to hold the brake hard to keep it from going.. I think drag slicks are a great idea too.

I don't know the exact stall. The TC feels great and is immediately responsive when I nail it.

Have you determined what your actual stall speed is? A PTC 9.5 should be a good piece.
And what is your starting line technique? Stab it from idle, full throttle to stall against the brakes, bring it to 2500 and stab it? It makes a difference, especially with poor starting line traction.

See above.

I've considered a gear change but gearsets for the 741 are limited. The 3.73 is available aftermarket but I would consider a used oem set.

 

[33 IMP]

You don't suck. You just haven't had as much practice as some of us who have been racing for
20.... or 30......or 50 years, or in the same car since the eighties,(me).
Without being able to stab the throttle at the green, and hook up!, you'll never see the full potential of the car. You are also giving away all the torque multiplication of a good torque converter that way too. Assuming a 4000 stall, how much more horsepower do you think you have at 4000rpm, compared to walking it off the starting line at 2000, 200? 300? Get it hooked up, leave at 3000 or 3500, it will be a half second quicker than your best.
Imo, even cheap used slicks , if they have ANY life left, are better than drag radials, if your spinning the DRs. The stock eliminator boys get rid of 9x30s as soon as they slow down, still have plenty of passes left for guys that don't have to be fast to survive.
Edit: 3.73s are only 5% lower than the 3.55s you have . I wouldnt bother for that. 3.91s or 4.10s,yeah.

 

[threewood]

I just went down a rabbit hole on drag slicks. They are a bit pricy lol. I think I need to stick with something that is DOT rated as most of the races I'll be in street class. Hoosier has one that is DOT rated for street legal class although they are not legal for the street.

I'm looking at 275/60 R15 Hoosier DOT2...$350 each.
Hoosier Drag Slick in 29x10 15 is $282 each (not DOT rated)
Rim is 15x8

 

[33 IMP]

I just went down a rabbit hole on drag slicks. They are a bit pricy lol. I think I need to stick with something that is DOT rated as most of the races I'll be in street class. Hoosier has one that is DOT rated for street legal class although they are not legal for the street.

I'm looking at 275/60 R15 Hoosier DOT2...$350 each.
Hoosier Drag Slick in 29x10 15 is $282 each (not DOT rated)
Rim is 15x8

Yep, tire prices have skyrocketed, but what hasn't. The ET street radial pro's i use on my Opel were $250 when I bought em, I think they are over $360 now. My big tires, Hoosier QT pros are over $480.(both are DOT, but supposedly not street legal. If it's got a DOT, it's legal) Some guy on the a-body side wanted L60x15, they are over $500 each! Nuts!

 

[threewood]

Yep, tire prices have skyrocketed, but what hasn't. The ET street radial pro's i use on my Opel were $250 when I bought em, I think they are over $360 now. My big tires, Hoosier QT pros are over $480.(both are DOT, but supposedly not street legal. If it's got a DOT, it's legal) Some guy on the a-body side wanted L60x15, they are over $500 each! Nuts!

Since I don't trailer the car, I don't think I should get true drag slicks. What is your take on driving to and from a track 35 miles away on drag slicks? Definitely not when rain is forcast.

 

[threewood]

There Is a bracket race this weekend I might enter to play around. I'll slap my MT E/Ts on and play with lower air pressure and burnout length.

 

[70ChargerRT]

A **gear change to steeper gears
(3.73:1, 3.91:1, 4.10:1, 4.30:1 etc.)
especially at altitudes
(RAD/corrected elevations is rarely what the real altitude is,
RAD it's usually always far higher)
IT will/can make a huge difference too,
& it's far easier to move a heavy car, with steeper gearing
it may make it a lil' less freeway/hwy friendly,
but great from stoplight to stoplight
(go to a slightly taller/stickier tires, will help)
but;
It will perform way better, across the rpm band,
especially if you can get it hooked
A lot of it, a dual purpose car, Street/Strip & performs well at both
(that's what God made N2O for )
it really comes down to & depends on what you can put up with,
neg. in one realm or the other
anything you sacrifice in one, hurts it somewhere in the other
It's really hard to have "your cake & eat it too",
to have perfect/friendly street manors & great performance at the track,
in both these realms

just because you can make more HP at WOT
a dyno isn't like driving a car, far more at play to street driving manors
needs to be considered

**get better tires & more traction, for the purpose to be used
if you really want to make improvements in ET
& a bigger diameter/taller tire, will have better/more ground contact patch

**exhaust cut-outs (manual or electric) & dumps like 12"-18" downstream
somewhere after your O2 sensors, you can reduce the size after that point
after the cut-outs, it will help if it's tuned for it
or the EFI can compensate for it,
then most the more restrictive exhaust/pipe size can be left alone

*intake/induction suited for your intended purpose
(or EFI nozzle/TB sizes & computer tuning)

**looser converter down low, that doesn't give up as much (slipping) in high gear
converters are really dependent on rear gearing, proper selection is key
& can make or break a combo with any street/strip car
& the camshaft, where it truly makes peak torque (to move you)
& WOT power (to get MPH, in the traps)
maybe have yours reworked

*It's not always the lack of horsepower, that harbors making good ETs
for what you got, the car's set-up do thou
HP is MPH
ET is the combo of the car & Torque to get off the line, move the car quickly

*it's "always" how you put it down to the track & how the car's combo works

**maybe also a thinner head gasket, will give you more compression too
(if you have the proper piston-to-valve & valve spring clearances)
altitude wants more
more advanced timing usually too

*any of the above will be way better at 60' times & that's really where
you can make up a shitload of ET, in the 1st 330'
a 1/10 improvement in 60', is like 3-4/10s in the 1/4 mile
without spending a small fortune

*suspension & good shocks is another subject 'all together'
that needs to be addressed too

Another easy band-aide even,
**go to 1.6:1 rockers (over the current 1.5:1)
will give you 10% more lift, more breathing
& a few %'s of degree's slightly more duration too,
both the in/ex valves, both will be staying open longer too
(that's if you have the proper piston-to-valve & valve spring clearances)
can go from the 0.558"in/0.564"ex GVL 'minus your valve lash'
(you're probably looking at currently 0.540"/0.545" ranges in reality)
to *0.595"in/0.597"ex gross valve lifts
(obviously, it's less with the #s in valve lash)


*EFI likes/will like a 110*-112* lsa better too
the EFI may be your limitation or choke point too, running out of fuel
or have the wrong fuel map, at the wrong time
FastmanEFI Richard Nedball is a member here, may want to talk to him

* just some options & my opinions
** better options, opinions will vary as vastly as the posts

all of it depends on how much you can cope with, and still be streetable
& how much you want to spend

good luck

View attachment 1471821

He don’t want any help. He can’t even answer if his car has been professionally tuned.

 

[BSB67]

Here are my thoughts based on the info provided. At a high level, I think that with tuning and practice, practice, practice, you could run a 12.70 at 109 without any motor changes or tire changes.

So I have another question: What is your goal?

Based on your time slip mph, your corrected hp on that run is estimated at about 480 hp assuming 4000lb race weight. With the parts you listed I would have guessed a little higher hp, but not much. My guess is that you can find another 20 hp in track tuning, maybe more. I think your compression ratio is about 10.0:1. Is that correct?

For a true street tire, your 60' is not that bad. But with practice you should be able to get to a 1.95. Also, try different shift points. The time slip with the 13.4 et had a better 60' than the one with 13.15. That is unusual and suggests something was going on down track on that pass, or maybe the tires broke loose after the 60' mark. Do you know?

Sticky tireswill help a bunch, for both a better 60' and will help you tune. If you want to make other motor related changes, you should look at cam, and compression if you run around at 3000 ft, IMO. Have you done a cranking cylinder pressure test?

Finally, there a two things you might look at that rob power. If you are using a cross flow muffler, like a Dynomax Super Turbo they can fail internally and that will suck 30 hp. I've had the Dynomax 17747 do this....twice. Also check that you have at least 3.5 psi fuel pressure at the top of the shifts.

Overall I think that you get the current package dialed-in before you make motor changes.

 

[threewood]

He don’t want any help. He can’t even answer if his car has been professionally tuned.

It isn't. Can you walk me through what a professional tuner can do for me?

Here are my thoughts based on the info provided. At a high level, I think that with tuning and practice, practice, practice, you could run a 12.70 at 109 without any motor changes or tire changes.

So I have another question: What is your goal?

Based on your time slip mph, your corrected hp on that run is estimated at about 480 hp assuming 4000lb race weight. With the parts you listed I would have guessed a little higher hp, but not much. My guess is that you can find another 20 hp in track tuning, maybe more. I think your compression ratio is about 10.0:1. Is that correct?

For a true street tire, your 60' is not that bad. But with practice you should be able to get to a 1.95. Also, try different shift points. The time slip with the 13.4 et had a better 60' than the one with 13.15. That is unusual and suggests something was going on down track on that pass, or maybe the tires broke loose after the 60' mark. Do you know?

I suggest that you get the current package dialed-in before you make changes.

Finally, there a two things you might look at that rob power. If you are using a cross flow muffler, like a Dynomax Super Turbo they can fail internally and that will suck 30 hp. I've had the Dynomax 17747 do this....twice. Also check that you have at least 3.5 psi fuel pressure at the top of the shifts.

My goal is to determine if my parts are working together well enough to get it solidly into the 12's at altitude. Looking for anything to improve times at the track. The cam I currently have works well but I think there are better profiles out there.
I like all the suggestions. I'm not going to throw parts at it yet. I'm going to drop the exhaust and play with what I have. I've never raced, plan to do it more often now that I have a track close and want to determine if a few small changes are beneficial. This will always be a street car.
Thanks.

 

[BSB67]

It isn't. Can you walk me through what a professional tuner can do for me?

My goal is to determine if my parts are working together well enough to get it solidly into the 12's at altitude. Looking for anything to improve times at the track. The cam I currently have works well but I think there are better profiles out there.
I like all the suggestions. I'm not going to throw parts at it yet. I'm going to drop the exhaust and play with what I have. I've never raced, plan to do it more often now that I have a track close and want to determine if a few small changes are beneficial. This will always be a street car.
Thanks.

Do you know what your cranking cylinder pressure is?

 

[451Mopar]

So I have been looking at my combo and thinking about getting a new cam with a bit more duration but was wondering if that is my bottleneck for more power. Not too woried about street manners and would like something a bit more lumpy at idle. I do intend to race a bit at the track in Roswell, which is 3573 elevation.

Here is what I currently have...
440 block, .040" over, stock stroke
Forged crank
KB 237 pistons zero deck
FelPro head gaskets .039" compressed
Stealth Heads, CNC ported (Intake 311cfm @.550 lift / exhaust 210cfm @ .550" lift)
Hughes 1.5 Rocker arms
Holley Sniper EFI 550 (650 max HP)
Holley Street Dominator single plane intake
1 7/8" long tube headers into 2.5" exhaust
Pertronix Ignitor III
Cam - Hughes STL3842BS solid lifter, 105* centerline, Duration at .050" 238* / 242*, Lift .558" I / .564" E
PTC 9.5" torque converter
3.55 rear end ratio on 275/65 R15 tires

Air in, air out right? I like the cam but the engine seems to top out a little over 5700 rpms, which is where the cam power band ends. I was thinking a similar cam with more duration to bump the power up into the 5900 - 6000 rpm range. Car has plenty of power down low as it sits. But am I hitting a road block with the intake or the headers or even the heads?

Best 1/4 and E.T at 3573 elevation was a 13.15 @ 106.81

Looking at the Hughes STL4650BS, centerline 104*, duration at .050" 246* / 250*, Lift .576 I / .588" E. I would be able to keep my springs as the specs are identical as to pressure. And I want to stay with solid lifter. I'm not interested in going roller.

Thanks!

That larger Hughes cam should be fine.
Need some sticky tires and/or suspension work to get the 60' times down around 1.8 seconds or less.