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Discussion Starter #1
I am looking at making somewhere in the neighborhood of 440hp at 7500 rpm, do I need to be looking into forged internals? If so what are peoples thoughts on Eagle crank and connecting rod and Mahle forged pistons? I am looking at recreating this kit but with my block http://www.fordracingpartsdirect.com/5_0L_MODULAR_STROKER_SHORTBLOCK_p/m-6009-a46x.htm.

I plan on pulling the engine out this winter and figure I might as well do this while I'm at it. Is this something that could be done myself in a garage or will I need to machine anything in the block? Thoughts?
 

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the stock internals on a 4.6 3V are safe to 500 REAR WHEEL HP.
but if you plan on pulling the motor it would be a good idea to upgrade to forged internals.

EAGLE internals OK but there not the best parts out there. they are made in china so they are low in $$$.
with that said, they sell thousands on thousands of parts, and you don't hear a lot of complaints about them so they can't be that bad.

you might look into Modular Motors for a stroker kit. they are selling a 5.0 stroker kit for under 3K. you don't even have to bore the block with their kit, just a light hone to seat the rings.
building a 5.0 is worth about 50 hp over a 4.6.
i know some people don't like modular motors for their parts. my buddy has used over 30 short blocks in the last 5 years from them without troubles.
my internals are USED Modular parts, crank and rods. i am shooting for close to 700 RWHP with my new motor.
 

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As Roy stated, first question is are you planning to go FI with the rebuild?
If so...then the question is mute...the answer is go forged or regret later, especially considering the cost differential is not that great in the scheme of things when rebuilding.
The second point is just that....even if you are not going FI and looking to go radical NA to that level, then the consideration is still the same...if you are rebuilding towards increased power output, then you may as well bullet proof your engine to help protect against detonation risks, especially when you're talking about spinning over 7k. That fact alone is enough to want to run forged...that is a lot of force/moment at play you don't want to put on cast parts.

I built my 302 with Manley forged pistons and rod
 

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I was making 489 rwhp and 429 rwtq with my '09 stock engine with the Vortech centri blower. I had zero issues, excellent mileage.

That said, I completely agree with Roy. If you are going to pull the engine I would definitely recommend MMR. They have excellent prices and then you could put a whipple, KB, Roush blower with tons of torque without hurting the engine.

I wanted immediate torque, and lots of it at a low rpm so I wimped out and bought an '11 GT and put a Roush blower on it.

Once you make 490 rwtq at 2,800 rpm you will never go back. By upgrading the internals, you will be prepared if you decide to go this route in a year or two.
 

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All said, it really does make economic sense to go 5.0 over 4.6 if more power & torque are your goal.

(edit) And yes, forged internals are stronger than stock.
 

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You'll likely upgrade your flywheel to an 8 bolt configuration with a beefier crank. You may want to upgrade your clutch and input spline to handle the higher torque, together with a tougher transmission as well. One thing leads to another when you start a project like this. Keep us posted and hope you can share some pics of the work.
 

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Interesting Thread!

I've been running the stock internals with 515 RWHP & 432.67 RWTQ and haven't had any issues. Brenspeed says I would have to beef up the internals to take it to the next level. I love the idea of the 302 kit with an upgraded clutch and a new transmission where first gear isn't gone in a split second, but that is a project where it would be hard, for me, to rationalize the time and expense. My buddy always says, "anything over 500 rwhp on the street is just bragging", and I would have to agree. If I was a serious drag guy, that would be totally different. Interesting thread, all the same. I can see where guys just go in for a new project at some point. Especially with some of the advantages of the newer Stangs, but I will always love the understated classic look of the 08-09 Highland Green Bullitt. Love the color.
 

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7500 rpm will require i-beam rods, and probably a lightweight crank. Also, for that kind of rpm I think it's better to go with 3.7" pistons to get to 5.0, and keep the stock stroke (big bore). The A46X block you referenced is only good for about 63-6500 rpm because its a stroker. The FR500C engine (Daytona Prototype, R50 "Cammer") is a 4.6 big bore 5.0 (with 4v heads), and it redlines above 7k rpm.

A stroker usually produces more tq in relation to its hp, but the big bore will most likely produce more hp/tq overall. Also, stroking reduces redline rpm.

From what I've seen, a 4.6 3v bored to 5.0 with lt's, cams, cai, intake manifold, and ported heads is good for about 390 rwhp. I'd also go with flat top pistons. Combined with the slightly smaller combustion chambers of the FRPP stage 3 heads, compression should be high 10's, close to 11:1. I'd add an Exedy Hyper Single clutch to go with this set up.
 

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Discussion Starter #9
Thanks everyone for the help. I have no plans on going with a forced induction setup just NA, if I want a car with boost I'll go get a Shelby. Modified Mustang ran a test and with the setup I'm looking at ran the engine to 7,600 RPM (Article http://www.mustangandfords.com/how-...fold-testing/intake-dyno-testing-results.html) and got about 430hp out of it, probably capable of more the tune didn't look quite on from the dyno results probably could make 440. Torque seems to top out around 360 so I'm not worried about the trans holding up. Clutch and Flywheel wouldn't be a bad idea with the engine out. And I agree with going big bore vs stroker, making it easier to hit those RPMs but was hopeful that the forged internals would be able to handle that kind of RPM, guess not.
 

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Discussion Starter #10
Another new idea, the boss 302 connecting rods, with the 2003 Cobra Kellogg crankshaft. Thinking the Mahle pistons still. Thoughts?
 

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Thanks everyone for the help. I have no plans on going with a forced induction setup just NA, if I want a car with boost I'll go get a Shelby. Modified Mustang ran a test and with the setup I'm looking at ran the engine to 7,600 RPM (Article http://www.mustangandfords.com/how-...fold-testing/intake-dyno-testing-results.html) and got about 430hp out of it, probably capable of more the tune didn't look quite on from the dyno results probably could make 440. Torque seems to top out around 360 so I'm not worried about the trans holding up. Clutch and Flywheel wouldn't be a bad idea with the engine out. And I agree with going big bore vs stroker, making it easier to hit those RPMs but was hopeful that the forged internals would be able to handle that kind of RPM, guess not.
That MM&FF article was a stock short block, with stock internals. The test is a bit misleading because spinning our engines to 7600 rpm is not a good idea. I have the cams, intake mani, tb, and cai featured in that article, and their hp/tq numbers are pretty close for those mods. My rev limiter is set at 6800. I called FRPP about this, and they said that's about the safe limit for the stock internals (even with ported heads).

Sean Hyland advertises a forged rotating assembly, stock bore/stroke, that's good for 7k rpm. To safely go above that you need higher-end forged internals.

Yes on the Kellogg crank and Boss rods. Those parts were built for high rpm, and should safely get you 7500. I'd look at flat top pistons to raise compression, for more upper rpm hp.
 

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Thanks everyone for the help. I have no plans on going with a forced induction setup just NA, if I want a car with boost I'll go get a Shelby. Modified Mustang ran a test and with the setup I'm looking at ran the engine to 7,600 RPM (Article http://www.mustangandfords.com/how-...fold-testing/intake-dyno-testing-results.html) and got about 430hp out of it, probably capable of more the tune didn't look quite on from the dyno results probably could make 440. Torque seems to top out around 360 so I'm not worried about the trans holding up. Clutch and Flywheel wouldn't be a bad idea with the engine out. And I agree with going big bore vs stroker, making it easier to hit those RPMs but was hopeful that the forged internals would be able to handle that kind of RPM, guess not.
Ah! That is the direction Ford went in 1970. The 429 CJ vs the 428 CJ. The fat pistons with the higher revving engine vs the old FE with the longer stroke.
 
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