LOL...It's still a heavy boat with floaty steering...but it sure is fun. I love the way it thumps now. I own a Mustang...512 RWHP SAE, low 12's at 116 MPH in the quarter on street tires, low 8's in the 1/8th - it won't get pounced

 

.. Well, you can still prowl around for those fox-body Mustangs that look like Mazdas... LOL!

 

dimora how many hp and tq on that engine? got almost the same set-up.

 

Tim Meyer says "I am guessing your power should be at about 375-384 HP And TQ should be about 465-475". I am assuming that is at the crank.

I may put it on the dyno just for fun.

 

.. Those numbers look conservative for all the goodies you put in there...

 

Update:

Man is this thing strong!

I found out a couple of things in the last two weeks.

1) My Edelbrock Performer 1405 600 CFM carb *may* be a tad too small for this build. I called Tim and spoke with him, and he said on my build he sees the best results with a 650 CFM carb...I also spoke with Edelbrock and I used a few online CFM calculators.

My numbers:

408CI
6000 RPM maximum
90% VE
637 CFM required.

Now with that said, the 90% VE is a best case guess. Most street cars (normally aspirated) with push-rod engines are around 80% VE maximum, but I have a custom cam, full hydraulic roller setup, 9.5:1 compression, and am running 15-33 degrees timing on 93 octane, and my best guess is that I may be able to come close to 90% VE with my build.

I was going to pick up an Edelbrock 650 CFM Thunder AVS series carb from Tim Meyer, but I found one on Ebay that is brand new (factory re-built) for $150 and I just couldn't pass that up, especially since I am handy at carb re-builds...so I'll pull the top off of it, clean the jets since it has been sitting on a car for a few years (never run), inspect the accelerator pump rubber and lube it, and make the swap.

I'll sell my just re-built 1405 600CFM in the classifieds or Ebay.

What started the whole carb size analysis is the car felt down on power vs. what I expected - that was all my fault, since I was not done tuning it up and verifying connections. I had neglected to adjust my kick-down rod screw on the carb after adding a 1/2" phenolic spacer...so the tranny was not down-shifting. Huge difference!

Secondly, I never finished curving my distributor.

With help from my lovely bride, I set my initial timing to 15 degrees, then adjusted my centrifugal advance springs to allow, at 3,000 RPM, timing of 33 degrees.

I hooked up the vac advance once all the above was set, and let me tell you, this thing screams now, especially down low!

I'll report back once I get the 650 CFM carb cleaned and installed.

Here is a blurry video my neighbor shot, but you get the idea:

 

Now you need a posi rear!

 

Yes, that was a bit of one-wheel peel!

2.75 rear end gears

 

.. Did I get those speeds right..?

.. Engine sounds good...

.. What size valves do those 302C heads use?

.. I have a Holley 650CFM spreadbore lying around I figured I would use when converting my 351M400 into a 400C... although if I had a 700 or 750 handy I would be using it... but it's just for an F150 4x4 SuperCab 8' bed truck, so not too concerned... current motor is sluggishly weak (75 MPH top speed!) and gas guzzler like most 1970's engines... want more power and better MPG... will prolly just use a 4bbl. to 2bbl. adapter for the stock manifold... maybe enlarge the 2bbl. holes if possible, gasket match the ports, remove any casting bumps/flash/other irregularities... use stock heads... domed pistons... Summit cam/lifters... stock rockers... C6 auto rebuilt at 98,000 hard (snowplowing, hauling, etc.) miles... about only 110,000 miles now... should already have plenty of 9" rear/front ends gearing... maybe add a bumper traction bar in rear to protect the leaf springs...

 

A couple of thoughts for you.

1: There is such a thing as too big a carburetor. If the engine is not turbocharged or supercharged, you want to match your CFM to the engine demands, and a standard calculator that gives you cubic inch inputs vs. RPM and volumetric efficiency is the way to go.

Here is a calculator:

Carb CFM Calculator

On 408 cubic inches, at 6000 RPM and 100% volumetric efficiency (VE), your carb size would be 708 CFM.

Since a normally aspirated engine will likely not exceed 90% VE even with a full roller setup and ported heads, over-sized valves, headers, etc. you are looking at 638 CFM being the very maximum.

2: I would consider picking up a used Edelbrock or Weiand intake - they are usually under $150.00, are light-weight aluminum, they dissipate heat better, and they make more power vs. trying to modify your factory 2V iron monster.

 

The 302C (australien head) use the same valves as the 2v head.

 

.. I use a vacuum secondary Holley 750 on my 425HP 351W and it doesn't seem too big at all... runs great from 500 RPMs to 6500 RPMs... tight throttle response... no bog... so I figure couldn't be any worse on a 450-500HP 408C...

.. I already have the iron 2bbl intake manifold, 650 Holley, and a couple 4bbl to 2bbl adapters lying around, so figure I might as well use them... this is just a budget build, and the weight of that truck is going to be on the heavy side no matter what... and I should have a satisfying amount of power anyway...

 

4" stroke need work to rev at 6500 rpm. Most 400 here don't reach 6500 rpm.4" is long and heavy. Really good for torque. 400 more torque than hp. Just my 02.

 

Ebay Edelbrock 650CFM Thunder AVS manual choke model arrived (Model 1805). Gave it a quick rebuild and it runs great! I can feel a bit more giddy-up at WOT, and it idles a tad bit better than the 600 did. The better idle may be because I turned the idle mixture screws out two full turns vs. 1.5 turns (Spec is 1.5-2.0).

My freshly rebuilt and very clean 600 CFM Edelbrock #1405 carb is for sale in the classified forums if anyone needs a good, clean carb - ready to ship! <---Edit: SOLD!

 

.. The idle circuits on 600 CFM carb.s don't seem to cope well with 350" and bigger engines... especially if they have more than a base level stock cam... I noticed the same definite improvement going from a 600 Holley to a 750 Holley on my 351W...

.. Also, the carb. size formulas assume a stock type engine... with a performance cam, a carb. 10% or so bigger than what the formula calls for works better overall...