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Howards cams
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Author:  HyperValiant [ Sat Nov 16, 2013 6:47 am ]
Post subject:  Howards cams
Hey fellas.been a while since Ive been here but still drivin a slant every day. I just picked up a new howards cam cheap and would like to know yalls opinion on it. .473 lift
255 duration
220 @.050
intake open 4.0
intake close 36.0
exaust open 44.0
exhaust close -4.0
I would like to know your thoughts on this particular cam and if it would be a good torque/daily driver cam in a 3000/3400# car with a manual trans 3.23 final drive with a 3.9 first gear ratio.Also are Howards cams good quality?
Thank you in advance
HyperValiant
Author:  HyperValiant [ Sat Nov 16, 2013 6:58 am ]
Post subject: 
Cam has 110 lobe center and intake centerline of 106
Author:  HyperValiant [ Sat Nov 16, 2013 7:04 am ]
Post subject: 
Also what compression do you suggest with this cam?
Author:  ceej [ Sat Nov 16, 2013 7:33 am ]
Post subject: 
A cursory look at the specs suggest it would be a good cam for your purpose.

I would classify it as "Mild." A touch more oomph than the 244 cam. With that LSA, it should have a fairly refined idle.

I haven't run a Howards Cam, so can't speak to quality, though I haven't heard of issues.

Compression can stand to be brought up, even with a stock cam.

9.0:1 SCR, results in an approximate 8.35:1 DCR with that cam, assuming stock bore, stroke, and a 500' altitude WAG on my part. That easily keeps you on regular pump gas.

CJ
Author:  HyperValiant [ Sat Nov 16, 2013 9:13 am ]
Post subject: 
Thanks Ceeg,the plans call for oversize engine builder valves and port work and adjusting the C.R. to suite.Will also be using Aussie speed short intake,dutra duals,and either a Eddie 500,Holley 350 2 bbl,Holley 390 4bbl,or Holley 465 4bbl.I also have a Erson 280/270 on the shelf.As I plan on this car being street driven alot ,I want good torque and decent milage. HyperValiant
Author:  ceej [ Sat Nov 16, 2013 9:41 am ]
Post subject: 
I've run all of the above carburetors, with the exception of the 465.

The Holley 2 bbl will not deliver on fuel mileage.

All around economy will be best with the 390 Holley. In town will suffer with the larger Holley, though once tuned in, it will deliver out on the freeway, so long as your going further than 30 miles. Any less, consider that combined mileage.

The Eddie/Carter will not deliver the economy the 390 is capable of, but will require far less tuning for good results.

Best in the Hooptie was delivered by a 390 for 23.9 mpg freeway. Around town that dropped off around 16 mpg. 600 Holley, 12/22. Carter 500 16/20.

Nice thing about the Carter, no gaskets below the fuel level. Change the primary boosters out from a 600, it's a 600. Re-jet the primary and metering rods as appropriate for the base, and your pretty close.
The stiffest primary metering springs you can install, and a small adjustment to the pump shot will be in order. Some builds will like a change in metering rods. I'm running base metering rods, but have a relatively large displacement slant with gobs of compression for a street engine.

The Holley will require different jets than come out of the box, the secondary spring, pump cam, shooter, and the power valve will need to be changed. To have adjustability for the secondary, you will want to get the secondary metering block jet kit, or will have to play with metering plates. There is a Mopar throttle lever kit that you will need as well. Save yourself a lot of grief and purchase a quick change secondary spring kit. Idle adjustment for the secondary is on the bottom of the carburetor. Re-install the bolt so you can adjust it without having to take the carburetor off the manifold. (Run it in from the other side of the throttle plate.)

The 465 will probably have emulsion ports that won't be appropriate for a slant six. You may find you need to modify the air bleeds to get it to pull fuel appropriately, or change out the metering block completely.

Wear gloves. Gasoline is toxic!

Have fun tuning! (Or go with the Eddie and have fun driving!) :D

2¢

CJ
Author:  DusterIdiot [ Sat Nov 16, 2013 9:55 am ]
Post subject:  Yikes...
Quote:
thoughts on this particular cam and if it would be a good torque/daily driver cam in a 3000/3400# car with a manual trans 3.23 final drive with a 3.9 first gear ratio.
I will assume that that was a typo and you are using a 3.09 1st gear A-8333OD? If so the car will respond better and still get excellent mileage if the rear gearing is a 3.55.
Quote:
the plans call for oversize engine builder valves and port work and adjusting the C.R. to suite.Will also be using Aussie speed short intake,dutra duals,and either a Eddie 500,Holley 350 2 bbl,Holley 390 4bbl,or Holley 465 4bbl.I also have a Erson 280/270 on the shelf.As I plan on this car being street driven alot ,I want good torque and decent milage.

Nix the Holley 465 it will give the same mileage as the Holley 600cfm...(11-13 mpg...but good power for racing if you have the build to support it ...using the howard cam won't...), stick with the Holley 390 of Eddy 500 AVS. Make sure you do the portwork and bowl blending with the new valves as that is key to making the most developed power.

As Ceej showed the cam is a very short cam and the DCR comes up pretty fast, with an 8.3:DCR you will be looking at running plus or super pump gas as a standard....the torque band will be flatter but you will be limited on useful rpm...if this is 100% street no problem there, but if you decide to race you will be at your power limit with the change in rpm on the upshift. I also know from experience as I ordered a comp CCX cam that was similar to the Howard cam (256 adv dur, .466 lift, same LSA), that the cam was a little sluggish up to about 2000 rpm, then was responsive after that- that was in a the beater valiant with a 3 spd transmission and 2.94's...mileage was not stellar compared to the comp 252 and hyper pak setup in my feather duster)

If you want to get a bit wild, you can use the Erson 280/270 cam and build for a 10:1 SCR which if degreed right will have a bit lower DCR, and will provide the same torque and power level at street rpms as well as mileage, but will allow you to run the tach up to 4K without the engine falling short if you need to "pass" on the highway or go to the races.

Lots to think about, and always a road not taken.

-D.Idiot
Author:  HyperValiant [ Sat Nov 16, 2013 3:09 pm ]
Post subject: 
Thanks DI ,I dohave a 280/270 that will probably get used.that wasn't a typo,I am using a 5 spd dakota tranny that does indeed have a 3.9 first gear. Thank you for the info on the cam.
Author:  HyperValiant [ Sat Nov 16, 2013 3:16 pm ]
Post subject: 
DI ,what do you suggest on decreeing the erson 280/270 cam?
Thank you
Author:  DusterIdiot [ Sat Nov 16, 2013 7:04 pm ]
Post subject:  I set...
Quote:
DI ,what do you suggest on decreeing the erson 280/270 cam?
I set mine at 107 centerline the first time around, I regasketted the engine and set it to 103.5 before I pulled it out of the Mint Duster. I did not feel any difference in performance from either setting. You might play around with your build on a DCR calculator to see where a comfortable DCR sets up to your liking.

-D.Idiot
Author:  Dart270 [ Mon Nov 18, 2013 12:04 am ]
Post subject: 
170 or 225 motor? Howards has good rep.

Lou
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