Previous Thread
Next Thread
Print Thread
Page 2 of 3 1 2 3
Re: 512 low deck street engine [Re: fast68plymouth] #3097094
11/25/22 04:27 PM
11/25/22 04:27 PM
Joined: Aug 2003
Posts: 40,823
Bend,OR USA
C
Cab_Burge Offline
I Win
Cab_Burge  Offline
I Win
C

Joined: Aug 2003
Posts: 40,823
Bend,OR USA
I've notice that all the street and strip motors I've built for pump gas with less than 10.5 to 1 compression made more torque than HP with aluminum heads, no matter which cam, intake or carb size, confused
Motors above 10.5 to 1 compression made more HP than torque shruggy


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: 512 low deck street engine [Re: AndyF] #3097100
11/25/22 05:19 PM
11/25/22 05:19 PM
Joined: Jan 2003
Posts: 14,171
So. Burlington, Vt.
F
fast68plymouth Offline
I Live Here
fast68plymouth  Offline
I Live Here
F

Joined: Jan 2003
Posts: 14,171
So. Burlington, Vt.
Quote
In my experience, almost every customer asks for more power than they are actually willing to live with!


I’d agree with that.


68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
Re: 512 low deck street engine [Re: Cab_Burge] #3097102
11/25/22 05:34 PM
11/25/22 05:34 PM
Joined: Jan 2003
Posts: 30,211
Oregon
A
AndyF Offline OP
I Win
AndyF  Offline OP
I Win
A

Joined: Jan 2003
Posts: 30,211
Oregon
Originally Posted by Cab_Burge
I've notice that all the street and strip motors I've built for pump gas with less than 10.5 to 1 compression made more torque than HP with aluminum heads, no matter which cam, intake or carb size, confused
Motors above 10.5 to 1 compression made more HP than torque shruggy


That is just because they didn't have a big enough cam in them. A pump gas engine can be set up to make top end power with the correct cam, intake and carb. About the only people who build engines like that are NHRA stock or super stock guys since most people would just add compression to make more power.

Re: 512 low deck street engine [Re: fast68plymouth] #3097103
11/25/22 05:37 PM
11/25/22 05:37 PM
Joined: Jan 2003
Posts: 30,211
Oregon
A
AndyF Offline OP
I Win
AndyF  Offline OP
I Win
A

Joined: Jan 2003
Posts: 30,211
Oregon
Originally Posted by fast68plymouth
Quote
In my experience, almost every customer asks for more power than they are actually willing to live with!


I’d agree with that.


Yeah I'd say that we have several customers every year asking for 700 hp street engines. Once we ask them if they really, really want a 700 hp street engine they usually back off to "well, perhaps I'd be happy with 600 hp". We did do a 700 hp street engine for a guy with a four speed car. The car wasn't driveable so he pulled the four speed out and swapped in a 727 with a high stall converter and then he could drive it. He drives it to work on nice days. It is a bear of an engine but he makes it work.

Re: 512 low deck street engine [Re: AndyF] #3097107
11/25/22 05:50 PM
11/25/22 05:50 PM
Joined: Jan 2003
Posts: 14,171
So. Burlington, Vt.
F
fast68plymouth Offline
I Live Here
fast68plymouth  Offline
I Live Here
F

Joined: Jan 2003
Posts: 14,171
So. Burlington, Vt.
I generally look at the final overall gear ratio and the cruise rpm.
Then talk with the customer about their tolerance for poor drivability, and try to come up with something of a compromise between the desired power and street manners.

Sometimes the goals and the combos are really too far apart to fix with a cam.

It’s certainly better/easier when all the parts for the combo and the goals for the car are on the same page.


68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
Re: 512 low deck street engine [Re: fast68plymouth] #3097122
11/25/22 06:51 PM
11/25/22 06:51 PM
Joined: Dec 2004
Posts: 10,414
Rittman Ohio
fourgearsavoy Offline
I Live Here
fourgearsavoy  Offline
I Live Here

Joined: Dec 2004
Posts: 10,414
Rittman Ohio
I really should have listened to you guys when I swapped cams a few years ago. You both thought my choice was a little to rowdy for a 10 second stick shift street brawler.
So now I'm changing springs and putting a smaller street roller in my engine now so it's more drivable on the street.
I appreciate your input and now I'm heeding your advice bow

Gus beer


64 Plymouth Savoy
493 Indy EZ's by Nick at Compu-Flow
5-Speed Richmond faceplate Liberty box
Dana 60
Re: 512 low deck street engine [Re: fourgearsavoy] #3097229
11/26/22 10:37 AM
11/26/22 10:37 AM
Joined: Jan 2003
Posts: 14,171
So. Burlington, Vt.
F
fast68plymouth Offline
I Live Here
fast68plymouth  Offline
I Live Here
F

Joined: Jan 2003
Posts: 14,171
So. Burlington, Vt.
For me, time has changed what I feel is “streetable”.

Something I might have thought was “acceptable” 30 years ago......... is a often a no-go for me now.


68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
Re: 512 low deck street engine [Re: fast68plymouth] #3097385
11/26/22 08:24 PM
11/26/22 08:24 PM
Joined: Jan 2003
Posts: 28,002
Irving, TX
feets Offline
Senior Management
feets  Offline
Senior Management

Joined: Jan 2003
Posts: 28,002
Irving, TX
Originally Posted by fast68plymouth
Quote
In my experience, almost every customer asks for more power than they are actually willing to live with!


I’d agree with that.


I guess I was a bit of an odd ball (again) when I called up asking for torque instead of power and had a vacuum number in mind.

As for the heads, the numbers you got are about what I expected.


The heads are still a sticking point in my mind. I kinda backed myself into a corner with the pistons. Better heads would likely wake up the 541 nicely but the smaller ports I've got might make it feel a bit more responsive on the street. Just what a 5300 lb cruiser needs. biggrin


We are brothers and sisters doing time on the planet for better or worse. I'll take the better, if you don't mind.
- Stu Harmon
Re: 512 low deck street engine [Re: fast68plymouth] #3097423
11/26/22 10:53 PM
11/26/22 10:53 PM
Joined: Aug 2003
Posts: 40,823
Bend,OR USA
C
Cab_Burge Offline
I Win
Cab_Burge  Offline
I Win
C

Joined: Aug 2003
Posts: 40,823
Bend,OR USA
Originally Posted by fast68plymouth
For me, time has changed what I feel is “streetable”.

Something I might have thought was “acceptable” 30 years ago......... is a often a no-go for me now.
Not me, I like a lot of power, at the track and on the street devil boogie grin


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: 512 low deck street engine [Re: feets] #3097430
11/27/22 12:03 AM
11/27/22 12:03 AM
Joined: Jan 2003
Posts: 9,675
Frostbitefalls MN (Rocky&Bullw...
gregsdart Offline
master
gregsdart  Offline
master

Joined: Jan 2003
Posts: 9,675
Frostbitefalls MN (Rocky&Bullw...
Better heads would likely wake up the 541 nicely but the smaller ports I've got might make it feel a bit more responsive on the street. Just what a 5300 lb cruiser needs. biggrin [/quote]
My guess is where the crossover point is for best torque between small and large port heads would be a big deciding factor. Look at the size of gen3 hemi ports compared to thier engine size. An example would be your current heads versus a 440-1, and fuel injection to help level the playing field. I bet a ported 440-1 head with a short duration cam and 1.7 rockers might be killer on a 541. Another example is the factory heads for hp 383 and hp440 were the same, along with the same cam!

Come to think of it, i have a set of killer 440-1 heads, 1.7 jesel rockers, and most of the parts to build a 580 inch street bruiser! Ok, now to find a perfectly clean Chrysler Imperial, 😁

Last edited by gregsdart; 11/27/22 12:10 AM.

8.77 153 mph best, 3055 lbs 528 indy 440-1 alky
Re: 512 low deck street engine [Re: gregsdart] #3097465
11/27/22 08:20 AM
11/27/22 08:20 AM
Joined: Oct 2015
Posts: 570
UK
rb446 Offline
mopar
rb446  Offline
mopar

Joined: Oct 2015
Posts: 570
UK
Come to think of it, i have a set of killer 440-1 heads, 1.7 jesel rockers, and most of the parts to build a 580 inch street bruiser! Ok, now to find a perfectly clean Chrysler Imperial, 😁



Something similar to our street/strip combo 589ci wedge motor @10:1cr, a small .625" 260/270@.050 s/roller motor, 440-2 intake but with race 365cnc -13 heads, made 720ftlbs@4400 and 694hp@5500 at 33 deg.total and with a small old 950DP,....runs on pump V-power and should last well as its shifted@5800 and traps at just over 6000. Potential there for at least another 100hp with 2+points cr, more cam or even 1.7 jesels and a Dominator.

Last edited by rb446; 11/27/22 08:41 AM.

1969 'Cuda 446ci, best 9.96@133.9 in 1990
1971 340 'Cuda, best 11.01@122.8 in 1987
Re: 512 low deck street engine [Re: rb446] #3097491
11/27/22 10:18 AM
11/27/22 10:18 AM
Joined: Jan 2003
Posts: 28,002
Irving, TX
feets Offline
Senior Management
feets  Offline
Senior Management

Joined: Jan 2003
Posts: 28,002
Irving, TX
Originally Posted by rb446
Come to think of it, i have a set of killer 440-1 heads, 1.7 jesel rockers, and most of the parts to build a 580 inch street bruiser! Ok, now to find a perfectly clean Chrysler Imperial, 😁



Something similar to our street/strip combo 589ci wedge motor @10:1cr, a small .625" 260/270@.050 s/roller motor, 440-2 intake but with race 365cnc -13 heads, made 720ftlbs@4400 and 694hp@5500 at 33 deg.total and with a small old 950DP,....runs on pump V-power and should last well as its shifted@5800 and traps at just over 6000. Potential there for at least another 100hp with 2+points cr, more cam or even 1.7 jesels and a Dominator.


What about part throttle response and low rpm cruise?

That's where peak numbers mean nothing. Gotta make solid vacuum for power brakes and to keep the EFI in its happy place.


We are brothers and sisters doing time on the planet for better or worse. I'll take the better, if you don't mind.
- Stu Harmon
Re: 512 low deck street engine [Re: feets] #3097499
11/27/22 10:38 AM
11/27/22 10:38 AM
Joined: Jan 2003
Posts: 14,171
So. Burlington, Vt.
F
fast68plymouth Offline
I Live Here
fast68plymouth  Offline
I Live Here
F

Joined: Jan 2003
Posts: 14,171
So. Burlington, Vt.
Feets........I’m looking forward to round two of the 541 dyno testing.

Quote
As for the heads, the numbers you got are about what I expected.


The ones I had here were CNC’d by KG, but I did the valve seat work and assembly.


68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
Re: 512 low deck street engine [Re: feets] #3097506
11/27/22 10:56 AM
11/27/22 10:56 AM
Joined: Oct 2015
Posts: 570
UK
rb446 Offline
mopar
rb446  Offline
mopar

Joined: Oct 2015
Posts: 570
UK
Originally Posted by feets
Originally Posted by rb446
Come to think of it, i have a set of killer 440-1 heads, 1.7 jesel rockers, and most of the parts to build a 580 inch street bruiser! Ok, now to find a perfectly clean Chrysler Imperial, 😁



Something similar to our street/strip combo 589ci wedge motor @10:1cr, a small .625" 260/270@.050 s/roller motor, 440-2 intake but with race 365cnc -13 heads, made 720ftlbs@4400 and 694hp@5500 at 33 deg.total and with a small old 950DP,....runs on pump V-power and should last well as its shifted@5800 and traps at just over 6000. Potential there for at least another 100hp with 2+points cr, more cam or even 1.7 jesels and a Dominator.


What about part throttle response and low rpm cruise?

That's where peak numbers mean nothing. Gotta make solid vacuum for power brakes and to keep the EFI in its happy place.


Throttle response is excellent, can't get into it at all without lighting the street tyres up though which I've never seen him do, car has 11" drums and no power, stops the car good, owner goes to shows with it, low rpm cruise is fine, we adjusted the carb using vac guage once at the track, it had 15" if I remember correct@around 900>1000 for what its worth. Its driven to the track and raced with full exhaust to bumper, I don't think he could've got a much better deal (£10k for the fresh motor) as its fulfilled all his requirements and more on track, but with that came the added expense of a Dana, a race 727/converter etc. etc.

Last edited by rb446; 11/27/22 11:30 AM.

1969 'Cuda 446ci, best 9.96@133.9 in 1990
1971 340 'Cuda, best 11.01@122.8 in 1987
Re: 512 low deck street engine [Re: rb446] #3097601
11/27/22 05:47 PM
11/27/22 05:47 PM
Joined: Nov 2013
Posts: 611
Southern Alberta
Uberpube Offline
mopar
Uberpube  Offline
mopar

Joined: Nov 2013
Posts: 611
Southern Alberta
That cam is pretty close to the bullet cam I have more 505 truck motor, 10.2:1 compression, but 270 heads and indy dual plane. Still waiting for dyno time.

Re: 512 low deck street engine [Re: AndyF] #3097666
11/27/22 10:49 PM
11/27/22 10:49 PM
Joined: Aug 2003
Posts: 40,823
Bend,OR USA
C
Cab_Burge Offline
I Win
Cab_Burge  Offline
I Win
C

Joined: Aug 2003
Posts: 40,823
Bend,OR USA
Originally Posted by AndyF
Originally Posted by Cab_Burge
I've notice that all the street and strip motors I've built for pump gas with less than 10.5 to 1 compression made more torque than HP with aluminum heads, no matter which cam, intake or carb size, confused
Motors above 10.5 to 1 compression made more HP than torque shruggy


That is just because they didn't have a big enough cam in them. A pump gas engine can be set up to make top end power with the correct cam, intake and carb. About the only people who build engines like that are NHRA stock or super stock guys since most people would just add compression to make more power.

That cam was a custom grind comp Cams solid roller cam made for Benshoff racing that I was able to buy from the owner before he used it.
It is 260 @.050 on the intake lobes with .420 lobe lift and 266 @ .050 0n the exhaust lobes with .409 lobe lift ground on a 108 LSA, I installed at 107 ATDC on the intake lobes and I ran 1.65 Harland Sharp rocker arms on it with the low deck Eddy six pack intake on my old pump gas 505 C.I.400 stroker motor in my old street Duster. It ran a best of 10.12 at 127. + MPH with that cam and standard port440 heads,. Switching the heads and intake to a set of Indy SR M.W. port heads and an Indy 400-3 intake with a stock Holley 9375 non HP list 1050 CFM carb pickup that car to 9,993 at 134.7 MPH cork up with the air cleaner on weighing 3450Lbs. with me in it at Woodburn in July at the Mopar race back when.
Those 75.0 CC Indy heads did change the compression ratio from 10.31 up to 10.78 to 1 and made it have more HP that torque with the same cam install the same with the same rocker arms and valve lash, I'm sure they flowed more air than either set of the standard 440 port heads I ran on that motor but the smaller CFM of the 1050 CFM Dominator carb versus the 1350 CFM of the six pack may have not made up for the increase by itself, it did make peak HP move up in the RPM range (peaked at 7300 RPM) and peak Torque at a higher RPM (5200 RPM) than the six pack set up did shruggy That motor with the six pack and 906 heads made 644 Ft. Lbs. torque at 4500 RPM and 612 HP at 5500 RPM
on the carb shop DTS engine dyno using CA91 octane pump swill back in 2002 in Ontario, CA in the spring before it got really hot down there. boogie
That motor and car exceeded my wildest hopes every time I change a part on it up boogie grin

Last edited by Cab_Burge; 11/27/22 10:56 PM.

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: 512 low deck street engine [Re: Cab_Burge] #3097798
11/28/22 01:35 PM
11/28/22 01:35 PM
Joined: Jan 2003
Posts: 14,171
So. Burlington, Vt.
F
fast68plymouth Offline
I Live Here
fast68plymouth  Offline
I Live Here
F

Joined: Jan 2003
Posts: 14,171
So. Burlington, Vt.
Originally Posted by Cab_Burge
I've notice that all the street and strip motors I've built for pump gas with less than 10.5 to 1 compression made more torque than HP with aluminum heads, no matter which cam, intake or carb size, confused
Motors above 10.5 to 1 compression made more HP than torque shruggy


10:1 446, Bowl ported RPM heads, SFT cam, victor, ported 850, dyno headers- 526tq/558hp

73A3E340-DF8A-4844-935E-CE6CE5B639DE.png

68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
Re: 512 low deck street engine [Re: fast68plymouth] #3097801
11/28/22 01:42 PM
11/28/22 01:42 PM
Joined: Jan 2003
Posts: 14,171
So. Burlington, Vt.
F
fast68plymouth Offline
I Live Here
fast68plymouth  Offline
I Live Here
F

Joined: Jan 2003
Posts: 14,171
So. Burlington, Vt.
10:1 410, bowl blended RPM heads, mild lobe SR cam, Victor, 1-3/4” headers, QFT 850 carb- 524tq/538hp

6467C1C9-7EA2-402E-9AED-7791EDEAEC54.png

68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
Re: 512 low deck street engine [Re: fast68plymouth] #3097830
11/28/22 02:42 PM
11/28/22 02:42 PM
Joined: Aug 2003
Posts: 40,823
Bend,OR USA
C
Cab_Burge Offline
I Win
Cab_Burge  Offline
I Win
C

Joined: Aug 2003
Posts: 40,823
Bend,OR USA
Thanks for posting them, you have probably built and dyno tested a lot more BB Mopar motors than I have bow
Keep up the good work up
BTW, do you mind sharing the cam specs on those toe motors? I hope so luck


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: 512 low deck street engine [Re: Cab_Burge] #3098053
11/29/22 10:36 AM
11/29/22 10:36 AM
Joined: Jan 2003
Posts: 14,171
So. Burlington, Vt.
F
fast68plymouth Offline
I Live Here
fast68plymouth  Offline
I Live Here
F

Joined: Jan 2003
Posts: 14,171
So. Burlington, Vt.
The cam in the 446 for that test was 264/264-109.
This was the second cam. First cam was 254/254-110.
Essentially no difference in power.
In the original configuration, both cams made about 520-525hp with 1-7/8” headers, SD intake, and ProForm 750 carb.

The bigger headers, victor, 2” super sucker, and ported 850 picked up the motor over 30hp.
That was just a test to see if we could exploit the bigger cam after seeing the first combo didn’t respond to the added duration.
If I had to do it over again, I would have used a slightly shorter cam than the first one.

The 410 cam was 251/259-108.
The target was 500/500....... so no changes were made.


68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
Page 2 of 3 1 2 3






Powered by UBB.threads™ PHP Forum Software 7.7.1