Magnum valve spring upgrade

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70Roadkill

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So I'm swapping in a magnum into my 70 swinger. Haven't decided on the exact cam yet but I know I need to update the springs if I want to run a larger cam, something to put me into the 11's. So my stock heads that I'll port (and yes I know all about cracking) but I can't afford EQ with this build. Too many other needs.

MagnumMopar closed shop, yes there is the hughes 1110 and some other website for over 200 wants for their springs and retainers.

What other option are there? I'm on a super tight budget and looking to save but yet get quality parts where I can. Are these seriously the only 2 options for magnum springs and retainers?
 

Springs don't have to be ordered by application. Just figure out all parts you want to use and order the springs by dimension. You need inside diameter, outside diameter, installed height, and the desired pressure that is dictated by your cam selection. The thing you can't really change much will be the installed height since I assume you are keeping original valves and valve length. The retainers will also limit choices here. It will take a light car and a well planned selection of parts to get into the 11s if you keep stock magnum pistons/compression. What other parts are planned for the engine build?
 
Simplest option would be the Hughes 1110SVK in kit form, springs, retainers, locks, and seals. good up to .540" with no machining if I recall correctly. Just need to check retainer to guide/seal clearance as a standard practice, Lots of posts here on them. Can you do all the measuring, mixing and matching and make it work with no machine work for your chosen cam all for cheaper and will it be a better combo? I'd error on it costing more, and being more work and all for no better or worse results.
 
Some say you can run the 3100 v6 geriatric motors spring?
 
I have a set of performance Magnum springs. They are #P5249464. Good to .525 lift. I don't remember if I have retainers or not. I'll have to look.
 
I have one set of Howards springs and one set of Elgin springs... both around 115/320lbs. The Elgin's are $30.00 the Howards $45.00... PM if interested.

I also have a pair of Magnum heads that have been machined for stud rockers arms, a set of 8 Si stainless 2.02 /8mm valves for Magnum heads and the 5/16 x 3/8 studs and Comp guide plates... I'd take $125.00 for everything (w/Elgin springs) plus the ride.
 
Google " LA confidential mopar"
That is a 318 Magnum motor build that was done for enginemasters. Used beehive springs, on Magnum RT heads.
I bought the motor and ran it in my old 71 Duster( 11.60's) ran it to 6500 all the time.
Maybe what he did might give you some ideas. Super attention to detail, made 477 horse on pump gas.
 
So I’ll be running a 3.73 8 3/4 sure grip converter to large bolt pattern.

Switching front suspension to 73 duster large bolt pattern as well for disc brakes and sway bar.

Have subframe connectors made and installed and will be making caltracs, 90/10 shocks up front and rancho adj in rear.

Trans will be 904, transgo tf2, used turbo action 3500 stall converter, talked to a&a trans and will be doing 5 friction disc mods.

360 will be stock short block, will be adding a windage tray, porting stock magnum heads, custom grind cam not sure what grind yet, headers, air gap, 750 Holley, .028 head gaskets to get me around 9.3-5 compression. Probably msd ignition. Should rip pretty good.

I have a son in college and a daughter about to goto college. Trying to do drag week 2019 on a tight budget. I have 0 mopar parts, so I’m swap meeting as much as I can.
 
Be tough getting into the 11's with what you have, unless the car is really light.
To give you an idea, i too have a stock shortblock 360 in a 69 Dart(3300 with my big butt in it)
First outing with the car it ran 12.20's. 950,( tried a 750 as well)single plane intake, stock eddie heads, 4.10 gears, 4500 flash 8 inch convertor and a 727. Cam was like 244/250, comp solid cam( forget the grind now), 530ish lift. With the low compression it was lazy out of the gate, even with an 8 inch convertor.
I have since made several changes to get it to run 11.20's.
It helps you have a 904, but the 3500 convertor and low compression will hurt, gears too, unless you have a real short 26 inch tire The dual plane intake will be your friend as well.
Look forward to hearing how it works out. Good luck.
 
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