Maximum horsepower without touching bottom end
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Joined: Apr 2008
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From: Stockton California
Maximum horsepower without touching bottom end
Hello all,
Can anyone tell me what is the maximum amount of horsepower for a 350 without touching the bottom end of the engine?
The setup I want is supposedly going to produce around 420 horses according to desktop dyno.
Compression isn't going to be over 9.2 an I'm going to upgrage to 3.73 gears and a beefed up 700r-4 rated at 550hp.
Thanks in advance!
Can anyone tell me what is the maximum amount of horsepower for a 350 without touching the bottom end of the engine?
The setup I want is supposedly going to produce around 420 horses according to desktop dyno.
Compression isn't going to be over 9.2 an I'm going to upgrage to 3.73 gears and a beefed up 700r-4 rated at 550hp.
Thanks in advance!
Melting Slicks
Joined: Mar 2005
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From: Austin TX
The rotating assy should be fine at 420 with an NA engine.
But 420 will be difficult with 9.2 compression ratio. You'll need to spin her about 6500+ RPM which means you'll need a cam in the 250 @ .50 range, which needs much more than 9.2
My opinion.
But 420 will be difficult with 9.2 compression ratio. You'll need to spin her about 6500+ RPM which means you'll need a cam in the 250 @ .50 range, which needs much more than 9.2
My opinion.
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From: Stockton California
L-42. I'm adding Brodix Ik180's so it should bring my compression up to 9.2, but I don't really want to touch the bottom end so should I just run with thinner gasket to bump up compression?
And how long is my engine going to last with 2 bolt mains and 420 horses?
And how long is my engine going to last with 2 bolt mains and 420 horses?
Race Director
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Depends on how much and how many times you want to use it!!
Seriously..the stock bottom end can handle 400-425 easily. The weak point will be cast pistons and make sure there is NO detonation. They won't last long that way.
JIM
Seriously..the stock bottom end can handle 400-425 easily. The weak point will be cast pistons and make sure there is NO detonation. They won't last long that way.
JIM
Le Mans Master
Joined: Jun 2004
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From: Seattle WA
St. Jude Donor '14
I generally consider the stock bottom end of a 2 bolt to be good for around 400 HP with stock bolts - 475 with ARP studs.
Completely agree that any detonation is going to end the party quickly.
I can't see 420 FWHP with the IDK180s - what cam/intake/headers are you using?
Completely agree that any detonation is going to end the party quickly.
I can't see 420 FWHP with the IDK180s - what cam/intake/headers are you using?
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From: Stockton California
*****
I generally consider the stock bottom end of a 2 bolt to be good for around 400 HP with stock bolts - 475 with ARP studs.
Completely agree that any detonation is going to end the party quickly.
I can't see 420 FWHP with the IDK180s - what cam/intake/headers are you using?
Completely agree that any detonation is going to end the party quickly.
I can't see 420 FWHP with the IDK180s - what cam/intake/headers are you using?
268 duration cam. performer eps manifold. full long tube headers, straight pipes.
I don't expect 420 from that little combo but desktop dyno says anywhere from 390 to 420 for a couple different scenarios.
I expect 350 at the wheels bud.
Le Mans Master
Joined: Jun 2004
Posts: 6,231
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From: Seattle WA
St. Jude Donor '14
268 duration doesn't tell me much - do you have a specific manufacturer?
I have DD Advanced and Dynomotion - if you email me the specs I'll take a swing; I've generally been within 5% or so.
I have DD Advanced and Dynomotion - if you email me the specs I'll take a swing; I've generally been within 5% or so.
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Racer
Joined: Jan 2008
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From: Northeast OH
I am interested in how this setup work out, too. Next year I would like to get my 1973 L-48 making 300 at the wheels and would rather not pull the engine. So if it can be done that'd be interesting.
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Joined: Apr 2008
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From: Stockton California
the cam is this one
http://store.summitracing.com/partde...4&autoview=sku
I'll keep ya'll posted on the progress but even if i don't have 400 horses, as long as my 0-60 is around 5 I'll be happy destroying ricers.
http://store.summitracing.com/partde...4&autoview=sku
I'll keep ya'll posted on the progress but even if i don't have 400 horses, as long as my 0-60 is around 5 I'll be happy destroying ricers.
Le Mans Master
Joined: Jun 2004
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From: Seattle WA
St. Jude Donor '14
I took a look at this combo tonight.
First comment is those heads flow to .500...so you need more lift.
http://www.brodix.com/heads/ik.html
As spec'd I saw 392HP@5500 with over 400TQ from 2500-5000 RPM...nice
Moving to the X274E cam took us to 402@6000 over 400TQ from 3000-5000 RPM. If you have the gears, it'd be worth looking at this cam or a retrofit roller if you have the cash.
IMHO, that's as far as that combo goes without more CR or even more cam...probably a retrofit roller. You'd need to make 440+ at the flywheel to get 350 at the rear wheels, using an 18% drivetrain loss (automatic).
Based on my experience, these are pretty realistic numbers - but all IMHO of course.
First comment is those heads flow to .500...so you need more lift.
http://www.brodix.com/heads/ik.html
As spec'd I saw 392HP@5500 with over 400TQ from 2500-5000 RPM...nice
Moving to the X274E cam took us to 402@6000 over 400TQ from 3000-5000 RPM. If you have the gears, it'd be worth looking at this cam or a retrofit roller if you have the cash.
IMHO, that's as far as that combo goes without more CR or even more cam...probably a retrofit roller. You'd need to make 440+ at the flywheel to get 350 at the rear wheels, using an 18% drivetrain loss (automatic).
Based on my experience, these are pretty realistic numbers - but all IMHO of course.