Barracuda Challenger Forum

Author Topic: Grassroots 400, think it will crack 350hp?  (Read 1268 times)

Offline rUNCHARGER

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Re: Grassroots 400, think it will crack 350hp?
« Reply #15 on: March 02, 2017 - 05:24:30 pm »
We've all been there, that's why we recommend what we do. i did a set of 915's about 10 years ago, put 2.14 and 1.81 in them, ported them myself but you still need the machine shop to surface them and cut the seats. the investment was exactly what the new Edelbrocks cost, however I knew that going in and didn't want that goofy Edelbrock look.

Sheldon




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Re: Grassroots 400, think it will crack 350hp?
« Reply #16 on: March 02, 2017 - 10:56:49 pm »
We've all been there, that's why we recommend what we do. i did a set of 915's about 10 years ago, put 2.14 and 1.81 in them, ported them myself but you still need the machine shop to surface them and cut the seats. the investment was exactly what the new Edelbrocks cost, however I knew that going in and didn't want that goofy Edelbrock look.

Sheldon

I did 915's last year for my Challenger, but I bought valves, seats, springs, retainers, keepers & guides all throughout Summit & traded labor so it wasn't to bad & on a car like my Challenger where I want it to look stock Eddies weren't an option....

For most engine builds these days putting together iron heads makes no sense....
JS27N0B 70 Challenger R/T Convertible  FJ5 Sublime, Show Poodle w/90,000 miles since resto
WS27L8G 68 Coronet R/T Convertible  PP1 Bright Red, Project
RM21H9E 69 Road Runner Coupe R4 Performance Red, Sold...
5H21C  65 Falcon 2 dr Wagon... Dog Hauler...

Offline Cazbah362

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Re: Grassroots 400, think it will crack 350hp?
« Reply #17 on: March 02, 2017 - 11:56:11 pm »
We have all done it. I agree, you have a set of heads you know are right!  Just a thought, spruced up 915's should pull pretty good money on EBay?


Offline RCCDrew

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Re: Grassroots 400, think it will crack 350hp?
« Reply #18 on: March 03, 2017 - 05:28:12 am »
Thanks for the honesty. Now time to get out the carbide burrs!

Offline Flatdad

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Re: Grassroots 400, think it will crack 350hp?
« Reply #19 on: March 30, 2017 - 01:58:56 pm »
Feeling a lot better about these cylinder heads now. Engine and head work have been on hold, while I repair the rear structure on the Challenger. Found some time this last weekend to paint up one of the heads. I liked the duplicolor engine primer, but not a fan of their Hemi orange paint. Its too thin and runny.
'70 Road Runner-B7 383 Auto, now with more cubes
'97 Ram 1500 Sport 4x4-Bright Red 318 magnum
'67 Belvedere II-Dark Blue 318 Auto, now owned by my brother
'73 Challenger Rallye-B5 318 Auto, had a 360 in it, SOLD :(
'42 Harley Davidson 42WLA-U.S. army green 45ci flathead
'71 Challenger R/T-B5 383 Auto, now 400 powered and rusty!
'86 W100-Yellow 318-2bbl 4x4 4spd, off road toy

Offline Cazbah362

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Re: Grassroots 400, think it will crack 350hp?
« Reply #20 on: April 01, 2017 - 10:40:30 am »
Those look nice, what head gasket are you going to run?

Offline Flatdad

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Re: Grassroots 400, think it will crack 350hp?
« Reply #21 on: April 03, 2017 - 04:07:40 pm »
Those look nice, what head gasket are you going to run?

Steel .020 gaskets to gain as much compression as possible on the 400. Haven't messed with ports yet, but was worried the heads would rust up without throwing some paint on 'em.

We had some nice weather over the weekend. The Challenger is going to take way longer than anticipated, so I dragged my old Road Runner out of hibernation once again...

The plan was to make the challenger a daily driver for this summer and fix up the Runner, but looks like the opposite is going to happen.
'70 Road Runner-B7 383 Auto, now with more cubes
'97 Ram 1500 Sport 4x4-Bright Red 318 magnum
'67 Belvedere II-Dark Blue 318 Auto, now owned by my brother
'73 Challenger Rallye-B5 318 Auto, had a 360 in it, SOLD :(
'42 Harley Davidson 42WLA-U.S. army green 45ci flathead
'71 Challenger R/T-B5 383 Auto, now 400 powered and rusty!
'86 W100-Yellow 318-2bbl 4x4 4spd, off road toy

Offline Cazbah362

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Re: Grassroots 400, think it will crack 350hp?
« Reply #22 on: April 04, 2017 - 11:17:07 pm »
Cool RR, good luck on the port work, assuming you are looking to match port to exhaust and intake?  I get the change in direction, some times its best to put the toys away and take a break, drive around and enjoy the weather from the front seat of an old Mopar.  When life was much simpler...

Offline Chryco Psycho

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Re: Grassroots 400, think it will crack 350hp?
« Reply #23 on: April 08, 2017 - 07:58:21 pm »
Cool 70 RR  :2thumbs:

Challenger - You`ll wish You Hadn`t

Offline Flatdad

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Re: Grassroots 400, think it will crack 350hp?
« Reply #24 on: April 20, 2017 - 10:23:10 am »
Cool RR, good luck on the port work, assuming you are looking to match port to exhaust and intake?  I get the change in direction, some times its best to put the toys away and take a break, drive around and enjoy the weather from the front seat of an old Mopar.  When life was much simpler...

Got all fired up to work on the challenger again last night. I hadn't thought about port matching the exhaust side before. Funny thing is, I think the passenger side is going to end up with a nice painted up Flowtech to replace the smashed up hooker header while the driver's side will have to keep the old rusty hooker because of power steering clearance issues with the Flowtech. Lol

To throw a wrench into things, I spotted this on Craigslist today. Its just a ten minute drive, the piston compression height looks decent from the picture and I spy a forged crank. If the walls are decent, with it being a short block it would be easy to give a quick hone, re-ring it along with new bearings, and swap the other bits from the 400. A spare forged crank torque converter is in the shed.

https://fortwayne.craigslist.org/pts/6089928807.html

Waddaya think? Stick to my plan or take a short drive? I've got perfectly good calipers with the depth gauge doohickey and steel straight edge...
'70 Road Runner-B7 383 Auto, now with more cubes
'97 Ram 1500 Sport 4x4-Bright Red 318 magnum
'67 Belvedere II-Dark Blue 318 Auto, now owned by my brother
'73 Challenger Rallye-B5 318 Auto, had a 360 in it, SOLD :(
'42 Harley Davidson 42WLA-U.S. army green 45ci flathead
'71 Challenger R/T-B5 383 Auto, now 400 powered and rusty!
'86 W100-Yellow 318-2bbl 4x4 4spd, off road toy

Online 1 Wild R/T

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Re: Grassroots 400, think it will crack 350hp?
« Reply #25 on: April 20, 2017 - 11:27:01 am »
Those dished pistons are the kiss of death for making power... :2cents:
JS27N0B 70 Challenger R/T Convertible  FJ5 Sublime, Show Poodle w/90,000 miles since resto
WS27L8G 68 Coronet R/T Convertible  PP1 Bright Red, Project
RM21H9E 69 Road Runner Coupe R4 Performance Red, Sold...
5H21C  65 Falcon 2 dr Wagon... Dog Hauler...

Offline 734406pk

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Re: Grassroots 400, think it will crack 350hp?
« Reply #26 on: April 20, 2017 - 10:01:43 pm »
Those dished pistons are the kiss of death for making power... :2cents:

 :iagree:
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline Flatdad

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Re: Grassroots 400, think it will crack 350hp?
« Reply #27 on: April 21, 2017 - 07:19:54 am »
I didn't go look at it. Did some calculation assuming the dish volume @ 15cc and maybe .040 in the hole, the CR would end up no better than the current flat tops in the 400. Thanks for the advice guys. Sticking with the original "cheap" hop up plans.
'70 Road Runner-B7 383 Auto, now with more cubes
'97 Ram 1500 Sport 4x4-Bright Red 318 magnum
'67 Belvedere II-Dark Blue 318 Auto, now owned by my brother
'73 Challenger Rallye-B5 318 Auto, had a 360 in it, SOLD :(
'42 Harley Davidson 42WLA-U.S. army green 45ci flathead
'71 Challenger R/T-B5 383 Auto, now 400 powered and rusty!
'86 W100-Yellow 318-2bbl 4x4 4spd, off road toy