magnum build

[running]

Got my magnum engine stripped down. Its got a 120,000 miles on it. From what I can tell the cylinder walls loom good. But any info on what I should be looking for please let me know. Going to put new rings and bearings in it next time I have a chance to work on it.

The pistons have a 4 stamped on it. I'm assuming that means 4 inch bore. I'm assuming its a stock bore but want to be 100 percent certain before getting rings.

Leaning towards the eq heads. Not sure on the valve size. I'm guessing for a 400 horsepower build the smaller 1.9 valve size would be better. But I don't know?

Any help on this stuff greatly appreciated. This is my first build. I'm a rookie. Thankfully I got some help from my dad on things. But neither him nor I know much about what parts work best together for my goal of 400 horsepower. Or I should say anywhere from 380 horsepower and up is good. But I imagine to much over 400 would make the car less driver friendly on the road or cost more money than I want to spend.

I'm putting it in a 69 valiant. Its light and I think even 400 horsepower would make the thing fast enough for me. The goal at the drags is in the 12 second range.

Thanks!

 

[running]

I did a little more research on cylinder walls. Got some good pictures of what it is and looks like. My cylinder walls are pretty darn good from what I can tell. I can clearly see crosshatching from just below where the pistons come up to.

 

[zijmer]

hi iam doing the same. a 5.2 magnum in a 69 valiant 100 2dr post. my engine had good cylinders and pistons also. the crank was hurt tho. lack of maintance. the heads were cracked also. iam going to use a hughs cam (whiplash) there springs and retainers along with there roller rockers. i ditched the efi and went with an airgap intake. not sure about the carb yet. you can use the la 360 pan and timeing cover. i wanted to use the stock fuel pump. i know it wont be 400hp, but if it came close to 275 i would be happy. for the tranny i built a 904 lock-up with a factory high stall and the low ratio gearset. all that with a 2.76 rear gear should be a good all around crusier.

 

[Abodybomber]

hi iam doing the same. a 5.2 magnum in a 69 valiant 100 2dr post. my engine had good cylinders and pistons also. the crank was hurt tho. lack of maintance. the heads were cracked also. iam going to use a hughs cam (whiplash) there springs and retainers along with there roller rockers. i ditched the efi and went with an airgap intake. not sure about the carb yet. you can use the la 360 pan and timeing cover. i wanted to use the stock fuel pump. i know it wont be 400hp, but if it came close to 275 i would be happy. for the tranny i built a 904 lock-up with a factory high stall and the low ratio gearset. all that with a 2.76 rear gear should be a good all around crusier.

A great plug and play,your combination sounds fit. Mock & watch all assembly....

 

[Abodybomber]

Got my magnum engine stripped down. Its got a 120,000 miles on it. From what I can tell the cylinder walls loom good. But any info on what I should be looking for please let me know. Going to put new rings and bearings in it next time I have a chance to work on it.

The pistons have a 4 stamped on it. I'm assuming that means 4 inch bore. I'm assuming its a stock bore but want to be 100 percent certain before getting rings.

Leaning towards the eq heads. Not sure on the valve size. I'm guessing for a 400 horsepower build the smaller 1.9 valve size would be better. But I don't know?

Any help on this stuff greatly appreciated. This is my first build. I'm a rookie. Thankfully I got some help from my dad on things. But neither him nor I know much about what parts work best together for my goal of 400 horsepower. Or I should say anywhere from 380 horsepower and up is good. But I imagine to much over 400 would make the car less driver friendly on the road or cost more money than I want to spend.

I'm putting it in a 69 valiant. Its light and I think even 400 horsepower would make the thing fast enough for me. The goal at the drags is in the 12 second range.

Thanks!

My advice;: leave the short block alone! I would install a new melling low pressure/stock pump. E.Q heads, small valve version. An Air Gap intake,a single plane(M1 Mopar) if around 3:91-4:10's.. (no longer a daily driver).....

Camshaft depends on airflow. The 1.92 E.Q's flow 230-240,,with serious velocity. Learn from there.

 

[running]

My advice;: leave the short block alone! I would install a new melling low pressure/stock pump. E.Q heads, small valve version. An Air Gap intake,a single plane(M1 Mopar) if around 3:91-4:10's.. (no longer a daily driver).....

Camshaft depends on airflow. The 1.92 E.Q's flow 230-240,,with serious velocity. Learn from there.

Are you saying don't put new rings and bearings in it?

And thanks on the advice!

 

[running]

hi iam doing the same. a 5.2 magnum in a 69 valiant 100 2dr post. my engine had good cylinders and pistons also. the crank was hurt tho. lack of maintance. the heads were cracked also. iam going to use a hughs cam (whiplash) there springs and retainers along with there roller rockers. i ditched the efi and went with an airgap intake. not sure about the carb yet. you can use the la 360 pan and timeing cover. i wanted to use the stock fuel pump. i know it wont be 400hp, but if it came close to 275 i would be happy. for the tranny i built a 904 lock-up with a factory high stall and the low ratio gearset. all that with a 2.76 rear gear should be a good all around crusier.

Thanks for sharing! I'm pretty excited about getting my valiant going. I never see any others on the road. Found some disc brake conversion kits. And suspension upgrade kits. Thinking of doing one of those after I get the engine done. I got to eventually do something with my rear end. So not sure on the order of things.

 

[zijmer]

Thanks for sharing! I'm pretty excited about getting my valiant going. I never see any others on the road. Found some disc brake conversion kits. And suspension upgrade kits. Thinking of doing one of those after I get the engine done. I got to eventually do something with my rear end. So not sure on the order of things.

your welcome. thats what so good about this site, sharing. so still in the sharing mode, i dont know if you know, but maybe you do, and i wish i had knowen, 73-76 a body has all the suspention, disc brakes and diff you need and its just a bolt on. so if you were to find a beater for cheap, take what you need and scrap the rest. the scrap money mite make you break even. and the best thing is, its all mopar. my project was pulled out of a wrecking yard with the motor and tranny already gone. so i had to hunt down alot. got it all now though. you didnt say if you had a 5.2 or 5.9 magmun. it would be easier to reach your 400hp goal with the 5.9.

 

[running]

your welcome. thats what so good about this site, sharing. so still in the sharing mode, i dont know if you know, but maybe you do, and i wish i had knowen, 73-76 a body has all the suspention, disc brakes and diff you need and its just a bolt on. so if you were to find a beater for cheap, take what you need and scrap the rest. the scrap money mite make you break even. and the best thing is, its all mopar. my project was pulled out of a wrecking yard with the motor and tranny already gone. so i had to hunt down alot. got it all now though. you didnt say if you had a 5.2 or 5.9 magmun. it would be easier to reach your 400hp goal with the 5.9.

Its a 5.9. Thanks for the info!