Edelbrock 1409 vs. 1410 FrankenMerc 383

[kbsunlovers]

My Quadrajet hastened it's own demise by nosediving into the tarmac as I was loading it into the truck. Tweaked the throttle shaft and destroyed the choke pull-off and secondary airvalve linkage. Swearing ensued.

Moving on...

I'm pretty well sold on an Edelbrock as a replacement, with a mild aluminum dual plane. Question is whether to go for the 600 CFM or 750 CFM.

Here's what we're working on:
1992 One-Piece RMS 5.7 bored .030, 5.7" Forged Rods, Cast 383 Crank and Forged Pistons at about 9.1:1.
Stock Iron heads, just cleaned up a little. Certainly nothing high-flow here. Hydraulic flat lifters, stock cam
for the era. Block started life as a VP 5.7. Block & Manifolds are closed cooling. Built the bottom end to
be a tank - but being mindful of the limits imposed by the Alpha. Ignition is standard Thunderbolt IV

Hull is an 85 SeaRay 250 - moderately heavy for it's size, V-Hull. 25', approx. 4900 lbs. dry.

Merc MR Transom, Alpha 1 upper & lower 1.47:1 16x16 Aluminum 3-blade "Elephant Ear".
We're pushing past the rev limit with this prop - will probably look at some alternatives.

We typically cruise at 2900-3300. We like to be economical, but with grunt to get up on plane & battle
the commercial shipping wakes abundant on the Columbia River. We occasionally trailer up the the San Juans.

My gut tells me the smaller carb would be a better choice for me, but welcome opinions, experiences and WAG's.

Thanks in advance.

 

[Fastatv]

Re: Edelbrock 1409 vs. 1410 FrankenMerc 383

There is a basic formula ( CFM= CID x RPM x VE / 3456) for determining a good CFM match when plugging in the numbers for engine size, max rpm and volumetric efficiency. VE is assumed one, however, never is. The smaller carb should be your best choice. Too bad about the Q-jet....great carbs in my book. Anyway, hope this helps.

 

[achris]

Re: Edelbrock 1409 vs. 1410 FrankenMerc 383

At 30 thou over, your engine is now 355cu in... Using this CFM calc, you should be good to about 6500 rpm with the smaller (600cfm) carb, the 1409....

Chris..

 

[kbsunlovers]

Re: Edelbrock 1409 vs. 1410 FrankenMerc 383

Thank you for the input, gentlemen. I think you're both correct - even at 383 c.u. the 600 cfm version will be more than sufficient with stock heads and cam. I'm off to spend money.

 

[Bondo]

Re: Edelbrock 1409 vs. 1410 FrankenMerc 383

Thank you for the input, gentlemen. I think you're both correct - even at 383 c.u. the 600 cfm version will be more than sufficient with stock heads and cam. I'm off to spend money.

Ayuh,.... Welcome Aboard,.... With a 383 stroker, you could use either carb,...

But that said, tunability, 'n probably runability will be Better with the smaller carb,....

 

[Volphin]

Re: Edelbrock 1409 vs. 1410 FrankenMerc 383

I'd like some pics of that 383! That's my next project.

 

[kbsunlovers]

Re: Edelbrock 1409 vs. 1410 FrankenMerc 383



Here are some photos from the clearancing and mockup stages, and one install photo. If anyone
is interested in chatting about the process, send me a PM or we can start another thread.

For those who might be shopping for carbs, the major hotrod retailers all have part numbers 9909 and 9910, which are edelbrock factory remans of the 1409 and 1410. Price is in the $315 to $320 range....they don't show up if you're searching for 1409's....