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A lil Boost and too much Compression ='s...


Boost-n-Juice

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Well, I finally decided to tune/dyno the mustang. For those who know, this has been in the works for a little over 3 years now. When I ordered my short block form CHP I didn't intend on running the Novi 2000, just a little spray. I have the biggest pulley for the blower, hoping to not make more than 10-12 lbs of boost. The blower is good for 28psi. Well, at 10:1 and 9lbs it not only blew out my spark, but also blew the compression ring on my head gasket out of the engine. Literally it "blew" the head gasket. On the last pull if you watch in front of the front wheel, you will see a quick flash of fire and then black smoke comes out of the wheel well. Good times let me tell ya.

 

The car made 505 rwhp on basically 7 cyl, at 5,000 rpms, with only 9lbs of boost and a very safe 10:1 AFR. Oh yeah, the 42's were at 100% duty.

 

Back to the drawing board.

 

A HUGE thanks to Brian, Howard and Eric for staying until 1am to try and figure my mess out. They rock as always!

 

Enjoy...

Click here to watch 347-Dyno

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Guest chpmnsws6

Also remember what is next to go if the headgasket fails.... the rings.

 

Can you have your head porter open up the chambers for you? doing that and thicker HG might be just the ticket since you make the most power on a flat top piston. Also mentioned was the camshaft. Very good idea, didn't think about having the valve close a little later to bleed off cylinder pressures. But in the same aspect, couldn't you just back the spark timing down some also?

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The cam is a actually a custom cut Nitrous cam from Ultradyne. It's a big duration, I'll need to find my cam card.

 

I was running Sunoco Ultra 94

 

So the rings go next? It's Coast High Perf short block, so I'm not sure what the gap is set at.

 

I appreciate all the info. I think the blower is coming off for now and I'll go back to just spray.

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Guest Removed

if it was setup for spray, then stay that way....or you'll have to reconfigure some thing's to run boost..IMO(like blower grind custom cam, lower cr, etc)

 

even larger injectors, you get my point!

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if it was setup for spray, then stay that way....or you'll have to reconfigure some thing's to run boost..IMO(like blower grind custom cam, lower cr, etc)

 

even larger injectors, you get my point!

 

Yep, you're thinkin the same thing I am. The blower is coming off, guess I'll have to change my Screen name.

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Guest chpmnsws6
piston looks good though. No signs of detonation. Thumbs up to dynotune as usual.

 

I also noticed that *thumb*

 

Give your engine builder a call. If it was built for spray, they should have a decent amount of ring gap already. As i said, add a few more CC's to the cumbustion chamber somehow and back timing down/cam swap. A nitrous cam is VERY similar to a blower cam, just normally the nitrous cam has a lower LSA. You have a GOOD blower on it right now just to waste it on some junk crack. Are you running studs? If not, why not just give them a try first before you do all that extra work when it might be unneeded.

 

Just some opinions from your not so local newb though.

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Guest DSMkILLsV8s

up compression ratio or get a tougher prefereable copper head gasket and some tuffer head bolts prefere arp studs cause they take off less clamping force but keep in the combustion.but if u run to much a/f mixture in that cylinder and contain it in then u gota watch out for other things blowning like ur valves or cracking ur head .so basically u should just up ur compression by boring or geting pistons

 

thats the mind of DSM ;)

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WTF are you talking about?

 

He is already running 10:1 compression with a blower at 10 psi. He needs to lower his compression a bit to help with his current head gasket problems if he wants to run more boost.

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Guest DSMkILLsV8s
hey dumb ass whats lower then 10 9 so u saying he should run a lower compression as in ballow 10:1 u dumb fuck he needs to run higher as in maybe a 10.5:1 and up if u drop it then itll be to much cramed in the cylinder or in ur terms dee deee dee..lol. w/e i dont care.if im saying it backwords same difference u need to go higher then 10:1 maybe 10.5:1 or up
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