360 magnum. Safe boost rumours. True or false?

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maca

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Hey guys
Anyone had much experience with what boost can be run with what comps and with and without intercoolers?
I have a 360 magnum with 9.3 comp and ally heads. Its running a vortech supercharger and currently has 8psi at full boost but I will eventually be looking at upping it and have heard several different stories.
What I have read and been told is its safe to run up to 10 and maybe 12 without an intercooler or any water/meth on pump gas.
Then with an intercooler I can run up to 15psi.
15psi is around the most I would be able to run with my vortech anyway but I was also told if I run E85 I can run more timing hence more power.
Anyone had any experience with this at all?
cheers Maca
 
I saw a Hotrod magazine article online about that awhile back.
Try searching for "Hotrod magazine 5.9 magnum boost" and you might find it.

The only thing I really noticed was where they said they ran multiple races with 15 lbs and also with a 200 shot of NOS, but not at the same time of course.:D
And that they talked about intercoolers, Nitrous and E85 as well as meth.
 
Thanks
I have looked but cant find it. Sounds like its exactly what I want. Was it specific to magnums or 360s in general? I will keep looking
 
TrailBeast said:
I saw a Hotrod magazine article online about that awhile back.
Try searching for "Hotrod magazine 5.9 magnum boost" and you might find it.

The only thing I really noticed was where they said they ran multiple races with 15 lbs and also with a 200 shot of NOS, but not at the same time of course.:D
And that they talked about intercoolers, Nitrous and E85 as well as meth.
Click to expand...

Meth? They ran it on drugs?
 
maca said:
Thanks
I have looked but cant find it. Sounds like its exactly what I want. Was it specific to magnums or 360s in general? I will keep looking
Click to expand...

I'll see if I can find it again.
 
Well one of the nice things with meth is you can set it to come on at just the higher boost when you need it. Had meth on my srt4 and had it kick on around 15 psi at the time and max boost was 20. E85 if you have plenty of stations is good but you need more to make power. Have to run higher jets or injectors to compensate for the e85 over gas. Or run a mix of race gas and regular gas. I had the meth as the mixture then switched it up to straight meth and really made a difference
 
There is a guy on theturboforums that has ran a 360 mag with 16psi for a long time making 700rwhp. He has a forged and internally balanced rotating assembly, no block fill.

I'd say the block is fine and it's really more in the tune of the fuel and ignition is what gets folks into trouble
 
thanks guys. I have a couple of engine issues to sort 1st and then I will be upping boost. I think if I want to get to 15psi I will need an intercooler or meth 1st to be safe. I had a chat to some guys who have done both on supercharged engines and both said forget the meth and do the intercooler as they said they had better results with it. Meth would be easier to install though.
I think for now without either I will keep it around 10
 
My '74 LA 360 had a supercharger on it for a good amount of time. The internals were stock. When the supercharger was first put on it had about 7-8 psi of boost. When I got it, it was at 4-5 psi. Even though it was a running engine, when my engine builder took it apart, one of the pistons cracked in half and crumbled into the pan.
 
I have read the LA pistons were a sand cast piston which don't like boost and the magnum piston is a stronger hypereutectic piston. Don't know how true it is as the hotrod magazine i read yesterday referred to the magnum piston in there article as a cast piston. Mine have taken a fair bit of abuse.lol
 
Magnums use hyperecutectic cast Pistons. Manufactures can either cast or forge a hyperecutectic piston, casting being cheaper and that's what oem uses.
 
Are the magnum cast hyperecutectic pistons better than the older cast LA pistons. That's the info I have read in the past so I hope its right or I might have placed too much trust in them with my boost and HP.lol
 
What head gaskets are you planning on using?
Id suggest using Full groove main bearings as they provide full time oiling to the rod bearings......
 
I am not sure what full groove bearings look like but the bearings I used have a Grove on both halves. The head gaskets I used are multi layer gaskets.
 
maca said:
Are the magnum cast hyperecutectic pistons better than the older cast LA pistons. That's the info I have read in the past so I hope its right or I might have placed too much trust in them with my boost and HP.lol
Click to expand...
Any hypereutectic cast piston will be a lot stronger than standard cast, new or old. This is what makes the factory magnum short block such a deal when building an engine. Factory 9-1 hypereutectic pistons with moly rings...price that for an LA 360. Then there is the roller cam:thumbsup:
 
Like T56MaxTorq mentioned there are a couple of guys in the turbo forums that are running stock bottom ended 5.9s and making lots of HP. Look up 'Dizuster' and 'duner'.

I'm going to run a turbo on my stock 5.9 but intend on keeping it under 8psi with E85 and no intercooler.

BTW- are you running that Vortech setup in an A-Body? Would love to see how that fits in the engine bay.

Good luck with your project.
 
Yes its a 1974 australian valiant charger. If u Google one they are a nice looking car. Here is a pic. My battery is in the boot.
I will find a pic tonight as my phone won't let me paste on on this page at the moment
 
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i will add that in my experience an intercooler is much more reliable than meth inj and doesn't need refilling. You can add meth on top of adding an intercooler.

Also, do your research about intercoolers, they are not all created equal. I remember reading comparisons between ebay intercoolers and actual engineered intercoolers and it being a huge difference. I believe i remember the cooling capacity (surface area) doing its job correctly but the ebay ones flowing a lot worse and leaving some huge number like 50hp on the table.
 
^^ so true. But I can add from personal use of the cxracing products are cheaper but work just as good, the guy that owns it gets his cores from the same people some big names get theirs from. I ran a big front mount of theirs on my srt4, and only saw .5 psi drop across the whole thing, it was a 4" thick forget the width but took up almost the whole opening in the car. Something to look into to run a intercooler. I also put 30 psi through it and no problems
 
Thanks guys.
I was told by a friend running an intercooler that if the pressure drop is alot it needs a smaller cooler or smaller pipes.
Does this sound correct
 
Or it could be a bad intercooler, some name brand ones have 1.5-2.5 psi drop just on design alone. It just depends on pushing air, intercooler efficiency and how much air the engine can take. On v8s piping can be minimum 2.5 and as big as 3 just depends on the engine and air flow. My build (the setup from maddart) has 3" od piping off twin turbo and twin air/water intercoolers
 
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