LA/Magnum combo

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Minella

Minella

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Hello Guys,
I'm building an engine for a friend of mine and I'd like to discuss the combo, due to be really on a budget, follow:
Block: stock 318 0.030
Crank: stock forged
Heads: stock Magnum heads, no porting
rockers arms: stock
Cam kit: Summit 276º 286º, .471/.471, 114º
retainers: P4452032
Valve springs: P4876062
valve locks: P4452030
Pistons: KB187 hyper
Rods: Heavy Stock with arp fasteners
Oil pump: high volume
Oil pan: 2 qt. more than stock
Main studs: ARP
pushrods: cromoly 7.625
Headers: summit 1 5/8 x 3
Blower: Detroit 6-71, 12 psi
Compression: 10:1, on ethanol
Electronic fuel injection and ignition control, here in Brazil we have really cheap and good EFI systems.
In the Dyno 2003 is showing 475 HP at 6000 rpm.

The combo on a budget looks good? Any coments?

Best regards,

Minella
 
Sounds like a good setup, it'd kick my *** I know that much. Send me some of those cheap good injection setups lol
 
Actually they make de ECU and give support to build the all system
 
hehehe...Yeah, is a problem, try a translator.
Unfortunatle they don't have a site in english, yet.

Thanks,

Minella
 
I'm just concerned using stock rods and Hyper pistons. Anyone used a combo like this?

Best regards,
Minella
 
You cannot run boost with hypers. The rods should be ok. The pistons are asking for trouble. Also, with the 1.6 rockers, I'm not sure there's enough room for that lift (.502). It's right on the line. Check everything carefully...
 
Actually is 0.471 at 1.6 rockers. I really concerned about the pistons...

Thanks a lot,
Minella
 
12 psi is WAY silly high for this.
10-1 is twice as WAY silly high as the blowers psi.
Hypers can take a little blower pressure, but I would want a forged set myself.
IMO, you need to seriously rethink this.
 
Around 8 to 1 compression max with a turbo/blower setup at 12 lbs. Everything gets alot more stress. Definately forged pistons/rods and probably crank too.Cut the heads so you can run the proper spring setup.Good valves ( high quality stainless, especially exhaust)Heads could be ported a bit on the exhaust side. Cam needs to be very exhaust freindly with. I'd call Comp and ask for recomendations.
 
I wouldn't necessarily say the boost and compression are too high - he's running ethanol. A friend runs a blown 500 Caddy motor on Methanol in his lsr car and that's at 12:1 compression and at least as much boost. He does have good rods and pistons though.
 
I'm no authority on ethanol. I know ethanol injection reduces detonation. He is running a cast iron head which could be a contributing factor to detonation. A knock sensor and a timing management system may be the key. Seems like an expensive/complicated/exotic way to make 475 HP!
 
Thaks guys for the tips, If I reduce de compression to 9:1 and the boost for 8 psi., the hypers will do the job?
Another thing is the mopar springs, they only say that can handle 0.480-0.600 lift, anyone knows what is the rpm range?

Thanks a lot

Minella
 
Per info on the KB Pistons site, 9 to 1 static comp. ratio w/ 9 lbs. boost = 14-15 psi comp. ratio. That's alot for a Hyper piston to handle! Are you a gambler? The deck may be stacked against you with Hyper pistons! Go forged and sleep at night.
 
Thanks Sumbit,
I'll go on forgeds, and how about the mopar springs? Can run 7000 rpm?

Thanks a lot

Minella
 
Minella, I hope this info helps you: " had purchased a set of heads from a boneyard and decided to make this conversion.
I bought the appropriate retainer(P4452032) and went with the high lift spring (P4876062)
However, with the casting of my head was off such that the install height was only 1.60" instead of the recommended 1.64" height. This made spring seat pressure with the purchased spring being 149lbs.
Then I purchased and tried the weaker medium lift spring which was near the limit of my cam I was using. (0.520 Lift)
However at the 1.60"install height the seat pressure was still a whopping 139 lbs. Way too much for a hydraulic cam.
So in searching for another solution I wound up going with Crane as it appears to be the onlyother alternative.
Part numbers are:99840 for the spring and 99947 for the retainer. Using the MP locks as the 8mm valves are radial groove and not square groove.
This gives a install height of 1.58" which gives a seat pressure of 108 lbs. I did have to grind the guide some to get a proper clearance of seal/retainer, but wasn't expensive to get done. So, this is a solution for those that have poor castings that aren't to mopars supposed specifications" Good Luck!!
 
Thanks, Thanks a lot sumbit!
Those were the information that I need. Now my job will be easy. Very usefull tip.

Best regards,

Gustavo Minella
 
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