I would like to achieve maximum boost without blowing head gaskets so any ideas would be awesome. I am not sure with my setup how much boost I can get away with so I figured I'd ask some of you more experienced stangers with turbochargers. Here's the engine I bought. http://cgi.ebay.com/ebaymotors/FORD...33615QQitemZ8033646412QQrdZ1QQsspagenameZWDVW

I am using stock heads which I believe are 58cc combustion? The engine has 10:1 compression. How much boost should I run with that setup?

 

10:1 is pretty high for boost

 

John... Welcome... You probably want to do some digging on her around what others are doing. I'll tell you this much... While the CR is a bit high the most important thing at the level that I assume you are working in (given the money spent on the short block) is to manage your tune to ensure that you stay away from detonation. You might also spend some money on good head studs or at least quality aftermarket (ARP) head bolts and a quality head gasket set - maybe MLS since I assume that you have it apart. Then sneak up on your boost. As to a cap - there is no magic number. You can probably run enough to break other stuff first if you can keep the detonation away....

Just my 2 cents - others may give you something different....

 

Order some cometics in a thicker material, lower your combustion or get different pistons at least. Then throw some boost on it. Then if your still uncomfortable get a good methanol/water kit.

 

Good advice too....

 

Hopefully you opted for the forged pistons. 10:1+cast pistons+turbo=Kaboom!

 

If you can afford it get some aftermarket aluminum heads with bigger chambers that should help alot. Still the best thing to do is get the right pistons to give you a compression ratio of 8:1 or 8.5:1. Or you can run race gas.

 

I originally bought that engine to put aluminum heads on (no boost) but I bought the heads and cam used so I am not 100% sure what the specs. are and if everything was in good working order, it was too slow for my liking so something was up, not sure what though. That's the main reason I am going back to the stock cam and heads, plus the turbo kit I got is designed to fit on stock 5.0 engines. I was always under the impression that detonation was the main cause of blown head gaskets but maybe I'm wrong? How much boost should a stock 5.0 be able to handle? I've heard 7psi which doesn't seem like very much. I'd like to use the engine/pistons I have so maybe I can get a thicker head gasket or get the combustion chambers dished? I don't drive this car daily so anything "race" related would be fine too. I didn't get the forged pistons, just the silvolite pistons that came with it. I asked someone else who bought the same engine what he did with his and said he was running 150 shot of nitrous so I know the engine can handle a decent amount of performance.

Thanks for so many helpful responses!!

 

Anyone? Hello? *echo*

 

I've got a mp70 with a stock short block..personally mine loves 11psi. So far, the ground got too cold over here and had to call it a season before anymore boost was applied..I've seen people on here use as mush as 18psi on a stock 302 short block with good results...good luck...P.S I use just a felpro head gasket because I'd rather have a head gasket go than something more expensive...Your block will probably go before a good cometic gasket.....

 

You didn't give any info on your setup. What turbo, intercooled or not, head gaskets, Arp studs/bolts or stock bolts etc. You are most likely going to have to run race fuel or alky injection if you want to make any kind of power.

 

I'm using a fairly old but complete cartech setup that was used on an 87' Saleen but was installed back in 91' or 92'. Everything is still in good shape and turbo has been rebuilt recently. The kit is designed to work with a stock 5.0 so I'm pretty sure the turbo is a garrett T-44. I have an intercooler and definitley plan on using it. I'm using ARP head bolts and had planned on using regular felpro head gaskets. I'm just worried I have too much compression and will blow head gaskets too much. I only plan on running around 7psi. for now but I'd like to shoot for 10. I currently have the cylinder heads at a machine shop and was thinking about having them dish the combustion chambers to about 60cc to lower the compression. Any thoughts on that idea?

 

Just run race gas or a mix of pump/race and you should be good to go.

 

The problem with running high boost on a stock block with stock heads is.. The heads will "LIFT".. Good gaskets, O-ringing, none of that will really help..

You can run around 11 lbs of boost, if you keep the tune up soft, with race gas.. I ran 11 lbs of boost with a Kenne-Bell supercharger and stock (home ported) heads on a stock block.. I had the heads cut for Loc-Wire gaskets.. And one day in a street race, I hit the rev limiter.. Just the stuttering of the limiter, was enough to blow a head gasket.. And that was on race gas and with 7/16 ARP studs..

 

I have a 306 that makes 10:1 compression with stock heads. I'm thinking I'll just run 7psi. with 93 octane and get it tuned. They can add the 2nd tune for race gas and 9psi. if the tuners think it won't blow a head gasket right away. I guess I'll ask them and see what they say.

 

Just make sure the head bolts, head decks, and head gaskets are good.

What really matters is your tune. What do you have in terms of hardware?