Heads for a Magnum Stroker Engine

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Markh

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Greeting from the Essex EnglandView attachment 1715844950
We have been bought an ATK Magnum stroker short block from Summit (delivery options are limited for us in the UK). What would be a good cam and head combination, the engine is going in a 1972 Dart which is used for drag racing only.
The existing engine is a very tired 340 (hydraulic flat tappet cam and iron heads) but before it gets a freshen up we want to gain a bit more knowledge on car set-up (cal-tracs are waiting) before spending money.
The other option we have is to stroke a 1990 318 block that we have to a 390 using a forged Scat kit and add a mechanical roller cam and victor series race heads.
Any opinions would be much appreciated from any of the forum members.
We are currently running 12.2 seconds at 108 mph and a bit of wheelspin on launch
Happy new year to you all and thanks in advance for any replies
 
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Greeting from the Essex EnglandView attachment 1715844950
We have been bought an ATK Magnum stroker short block from Summit (delivery options are limited for us in the UK). What would be a good cam and head combination, the engine is going in a 1972 Dart which is used for drag racing only.
The existing engine is a very tired 340 (hydraulic flat tappet cam and iron heads) but before it gets a freshen up we want to gain a bit more knowledge on car set-up (cal-tracs are waiting) before spending money.
The other option we have is to stroke a 1990 318 block that we have to a 390 using a forged Scat kit and add a mechanical roller cam and victor series race heads.
Any opinions would be much appreciated from any of the forum members.
We are currently running 12.2 seconds at 108 mph and a bit of wheelspin on launch
Happy new year to you all and thanks in advance for any replies
I wouldn’t commit to any cylinder heads until you actually receive the short block and can verify whether it is an early or late Magnum block. (early Magnums still had provisions for head oiling) If it’s an early version with the head oiling you obviously can run the LA heads. You might luck out:thumbsup:
 
Markh, greeting! Welcome aboard!

Tell us a few things about the car now in order to not “Overkill” on suggestions.

What gear ratio is in what size rear end?
Tires currently in use?
Manual or automatic and if so, which one? (904 - 727)
The converter stalls at?
Weight of car?

Do you have the ATK short block now?
If so, does the block have a oil passage to send oil through the head?

Stroking a 318 to a 390 is a little more expensive than doing other stroker kits. Still, 390 is a pretty good move upwards in displacement.
Use a forged assembly for racing. It’s a little more expensive but it will be a more durable and stronger set up.
Are 360/5.9 engines hard to come by in England?
 
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From Edelbrock.com

NOTE: These heads are designed to accommodate stock Big Block Mopar Wedge rocker arm assemblies and aftermarket stock-like setups with a minimum of .150” intake offset. Ductile iron adjustable arms can be used but will require special clearancing of the rocker arm body in order to clear the valve spring retainers. Also, non-stock spec, aftermarket rocker arms may require special modifications. Please call Hughes Engines at (309) 745-9558 for compatible rocker arm setups.

Hughesengines rocker arm page for the Victor head;
https://www.hughesengines.com/Index...LaXRz&level3=RWRlbGJyb2NrIFZpY3RvciBIZWFkcw==
 
Thanks to 12many and Rumblefish360 for the replies
The car weighs 1320kg (approx 2900 lbs) with driver
Rear end is 4.1
Tyres are 28 x 9
904 auto, not sure of the stall as the car creeps forward at 2500 rpm so launching at 23/2400. We have a Wilwood brake pedal and master cylinder (for manual brakes) ready to fit to hopefully sort this.
We have been looking for a 360 core for around 3 months and no luck yet. The 318 is out of a low mileage dayvan and is standard bore so hopefully a good basis for a stroker.
Thanks for the heads up on the edelbrock victors, I have been reading everything I can find on the internet (Hughes and Campbell Engines) before I posted so I don't ask too many stupid questions, been collecting Mopars for a while and thought it was time to go racing. I understand that the Trickflow heads need different rockers as well
The ATK block is on its way so no chance to inspect it yet, I think the website says its a late magnum block, I probably should have waited and got some more information but it seems that most parts are in short supply
Best Regards
 
No worries on the questions. You have foreign car. 3rd of our big 3 which makes it a little harder. Correct and updated information is only made easy (relatively speaking) because of the internet.

2900 is a nice light weight. That’ll help a lot in the “go fast” category!

Allow me to redirect your eyes to the main front page of the racers forum and suggest you click on the stickies up top to look into the ET sections. These stickies I made a long while back in order to help direct people to do two things.

1; Stand up and toot your horn on your latest set up and what you have done. But with one simple request I put forth, tell everyone what parts you used and how you did it. Let your secret out in order to help others.

2; Help your fellow MoPar brother out when you list your stuff. Be sure to get everything listed and if a member should send you a private message, help them.

How fast do you want to go?
Click that section.
We have some really fast MoPar on here!
 
We are hoping to get down to 11.9 with the existing engine, with a new engine 10.9 would be nice.
Well, 12.2 to 11.9 is one thing. 10.9 is another.

Compression ratio?
What carb, intake and headers are you running?
What cam is in the engine now?
Specs please. Duration @.050, lift, LSA, intake LCA if possible.

To get into the 10 second area, I’m thinking a solid lifter cam. Like the MP .590. P4120657 104 overlap, 106 centerline, advertised @ 312 duration, 265-ish @050. I would use a single plane, 750 min. Carb size, min. 1-3/4 headers into a dual 3 inch exhaust.

MP calls for a lot of gear. 4.88’s with 10.5 X 30.5 slicks.
 
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I have a 2000 magnum engine in my 91 dakota sport race truck. Has KB107 pistons but stock crank and rods. I am useing the new trickflow heads. Have a comp 550 lift solid flat Tappet cam with oil through lifters, PRW roller rockers and Smith brother oil through push rods. With my set upbi think I am right at 11.1 compression. You can run LA heads on a latter magnum block as long as you have .
Oil through lifters
Oil through push rods
Rocker arms that will low push rod oiling.
I forgot to list that I have Howard's EDM lifters, PRW bullet steel 1.6 rockers and Smith brother 3/8th push rods.
 
The ATK is forged crank, pistons and rods. The pistons are a 23cc dish which doesn't help for compression
We haven't taken the 340 that is in the car at the moment apart at all since we bought it. Some of the lifters seem weak so they will be replaced before next time out, no idea what the cam is or the compression ratio or even the valve size. Its a 750 DP carb with 1 3/4" headers into a 3" exhaust.
The 28 x 9 tyres are on 7" rims and this is the biggest wheel and tyre that fits without starting to cut things about.
The 390 stroker kit from Scat we are looking at is forged pistons, rods and crank. Pistons are flat top with 4.7cc That will give over 12.1 compression with the victor heads which require 1 7/8" headers, it will become a strip only car then. At the moment, with a change of tyres, it is street legal with a valid mot (inspection) still in place
 
And thanks to mopar65 for posting, I am just about to look up and research the magnum parts you are using
and I appreciate replies from Rumblefish360 and 12many
 
And thanks to mopar65 for posting, I am just about to look up and research the magnum parts you are using
and I appreciate replies from Rumblefish360 and 12many
Hey no problem. There are a lot smarter guys on here than me. So was just posting what I have found to work for me. For got to add I have a indy single plane intake and a holley 650 DP thst was molded to flow 800 cfm. I race my truck on 93 pump gas. So far my best ET has been 11.24 in the 1/4 at 116 mph and my 1/8 is 7.15 at 96 . I think my truck has a low 11 or high 10 in the 1/4 in it. My converter is to loose on the top end. Over the winter I am going to send it to coan and see if they can tighten it up some
 
@mopar65, tell us about the cam your running & some more about the truck!
Its a comp cams 550 solid lift. The truck is a 91 short Bed that i put a cab and bed from a 96 on my 91 frame. The transmission is a turboaction built 904 with a coan 8 inch 5600 stall converter.. Ford 8.8 rear-end, full spool and 4.30 gears. Weld 15x10 with M/T 28x8.5x15 pro tires. The engine is nothing special. Was built for a stock block class. To wear if you was allways beating every body. Some one could come up and say they was going to buy the engine. If you said no you got kicked out of the class. If there is anything ekese you would like to know. Please ask.

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Here is a video my girlfriend took of the dakota my second time at the track.

 
Duration @050….


Runnin and duckin…. LMAO


Its a comp cams 550 solid lift. The truck is a 91 short Bed that i put a cab and bed from a 96 on my 91 frame. The transmission is a turboaction built 904 with a coan 8 inch 5600 stall converter.. Ford 8.8 rear-end, full spool and 4.30 gears. Weld 15x10 with M/T 28x8.5x15 pro tires. The engine is nothing special. Was built for a stock block class. To wear if you was allways beating every body. Some one could come up and say they was going to buy the engine. If you said no you got kicked out of the class. If there is anything ekese you would like to know. Please ask.

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Duration @050….


Runnin and duckin…. LMAO
Looks like I need to correct my info aittle bit. All my passes last year were on hoozer 28x9x15 slicks. I installed M/T 28x10.5x15 pro bracket Radials but haven't got to try them out yet.
 
Damn sucks getting CRS..lol also forgot to add. I have comp 1-5/8 full length headers. Wanted 1-3/4 or 1-7/8 but for some reason 1-5/8 is the biggest they make for my 91 dakota. Going to have to go custom it looks like
 
To the OP I hope I didn't take over your post. If I did I am sorry. I look forward to reading about your engine build. I hope to build a 13.5.1 compression 360/426 stroker engine for my dakota. Every one in my stock block class is now running 10.50 to high 9 in the 1/4 now. My low 11 are not going to cut it.lol
 
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