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gpeter7761

Active Member
Joined
May 22, 2004
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Location
Salida, CA
Here is what I'm building
Callies 3.79 crank
CompStar 2.100 x 6.125 rods
Diamond Custom Pistons 9.3 to 1
Joe Mondello Cryogenically Frozen Alecular bearings
Racer Brown flat Tappet Cam ST-21( Duration @50 254
554/520) and lifters
Racer Brown Magnum Rocker Arms
Cometic Gaskets
Complete New Magnum/LA heads Stage 3
EV-8 5/16 stem stainless valves
Hardened Exhaust seats
Pro Comp 3 angle valve job
Springs
Retainer
Machined 10* locks
650 mighty demon
air gap
What do you think?????
 
I think it is a GREAT combination - thought it was mine!!
Here is what I'm running - just to compare:
Mopar 3.79 crank
Platinum series I-beam rods 2.250 x 6.123 rods
Diamond Custom Pistons 10.5 to 1
Cl H series bearings
Racer Brown flat Tappet Cam ST-12( Duration @50 254
554/554) and lifters
Crane 1.6 Magnum Rocker Arms
Cometic Gaskets
Complete New Eddy Magnum heads Stage 1
EV-8 11/32 stem 2.02/1.625 stainless valves
Hardened Exhaust seats
3 angle valve job
Double Springs, moly retainer
Machined 10* locks
750 mighty demon
Magnum air gap

Dyno Sym says it makes 534hp @ 6100 and 520ftlbs @ 4500. you should be close.
 
Carb is a bit small, and I'm not sure why you would want to cryo treat bearings...It is great on other stuff...but bearings you dont want harder or deformed. Tell me more about the bearings...
 
Don is setting you up good. What are you doing with the car? Street car, raise the compression to 10.5 or so and use an additive when you race it. Unless you plan on standing on it on the street alot. The 750 mighty is a good choice. They flow cloe to 800 and can be jetted up alot.
Say hi to Don for me.
 
We are putting the motor in my grandmothers 68 Valiant ( 2800 lbs ) and it will be street drivin. Go out and make the boys in the new mustangs cry!! With the lousy gas here in Callyfornia (as Arnold says) price and octane, 9.2 to 1 seemed to be the best.
 
gpeter7761 said:
Hey Dart 388
Tell me more about how your's is running, assuming it is running

It runs pretty decent. I have not had it to the track since I put the Eddy magnum heads on it past winter - seat of the pants says there is more jam there than before. Last year it had ported 202/160 J type heads and ran a best of 11.66 at 113.5mph but seemed to run out of steam around the 1000' mark - so re the magnum heads, otherwise I'm quit pleased.

There is no such a thing as a 2800lb Valiant on the street, unless there has been a lot of gutting. my 68 Dart 2dr post which is as light an a-body as they come weighs in at 3100 with aluminum hds and intake, 727 and 8 3/4 w narrow aluminum front rims and 7 1/2 steel backs, aluminum fuel cell and 5 gals gas - so don't be too surprised when yours comes in at ±3200.

Send me a pm on your combo - and any queiries you might have.
 
I'm currently researching a similar combo to what some of you guys have done here, 'cept perhaps using a 318 as a base. 318 w. a 3.79" stroke makes 375". Then put a set of 1.92" valved EQ Magnums on it... I do have a 340 block I could use but I like the idea of the EQ heads since they can be procured pretty cheap, then ported and will outflow Eddys according to what I've read online. Although pricey, the 3.79" crank seems to be a really good part, perhaps a tad better than the ubiquitous (although cheaper) 4" arm.

Approximately how much did your bottom end cost when using the 3.79" crank? Seems to require custom slugs with this combo, apparently no one makes an off-the-shelf piston for it.

Any updates on how your builds went?


Thanks,

- Greg
 
Give Don a call at FBO he'll fix you up with the best stuff

I've read his page online about the 375" engine he built, sounds cool. His C/R was a little on the high side at 13:1. I'm definitely considering something similar.

How did your build turn out? What was the power like? Did you have to spin it higher than normal? Good street manners if that's the application? Inquiring minds want to know!
 
Why a 3.79 crank why not take it to 4" and get 416 c.i.???..compression is a little low for me,and the carb a little small....
 
My flat top piston, 13:1 compression, 3.79 stroke, 571 lift cam, 950 HP Holley Carb, 20 over 340 block in a 3500LB Barracuda goes 10:80's shifting at 5800 and going through traps at 6500. 3.79 strokers rule!
 
My flat top piston, 13:1 compression, 3.79 stroke, 571 lift cam, 950 HP Holley Carb, 20 over 340 block in a 3500LB Barracuda goes 10:80's shifting at 5800 and going through traps at 6500. 3.79 strokers rule!

That's it on the RPM? That's stock territory. I figured RPM potential to be higher, like 7+. Shows how much I know. Guess it depends on the combo but that seems low for a 13:1 mill.
 
That's it on the RPM? That's stock territory. I figured RPM potential to be higher, like 7+. Shows how much I know. Guess it depends on the combo but that seems low for a 13:1 mill.

Got as much torque as Horsepower. Don't need RPM to go fast. This motor was built to live. We set the piston out of the hole 18 thousands to get Compression. The heads are the key to the combination. big valve and lots of flow at 6000 rpm. Also the right center line cam helps to make the torque. It 60's at 1.47 -1.48 all day long. Needs lot of tire but not to tall. Leave the line at 4200.
 
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