Ok guys here's what I'm thinking. I have a 2012 F150 5.0 Screw that is bone stock for now. I have been looking at installing 5Stars Boss intake. However the Cobra Jet has the capabiliy of accepting a larger throttle body, up to 190mm I think. The Cobra Jet is a little shorter which may preclude any modification issues for fit. My questions are: Would I see much difference in performance between the two? Has anyone done this?

I am sure I will have more questions as the discussion unfolds, but for now any input or ideas are greatly appreciated.

Thanks,
Fyrbrd

 

Not sure where you're getting your information from, however, the Ford Racing Performance Parts catalog indicates ...The M-9926-CJ65 is 65mm (dual bore) and the M-9926-SCJ is 62mm (mono-blade oval).

Where are you getting your height measurement spec's?

COMMENT: Given that the COBRA JET 5.0L 4V INTAKE MANIFOLD has ... "Runners tuned for 7750 rpm peak power" OBVIOUSLY the intended application is full-race. Are you planning the rest of the engine build and performance mod's accordingly?

IF NOT, IMO it would truly be overkill and a waste of your $$$$$.

No dis', but is this just some delusional, desk-top build fantasy? *Like Al Gore's man-bear-pig.



------------------------------

-click- the pic'
Goth 150
< This space intentionally -blank- >

 

Hi Joe,

I think the easiest way to respond is to start with the last question first. To some extent, don't all engine builds begin as some delusional desk-top fantasy build? In my case, I am in the planning stages. Looking at what is available while trying to determine the best course of action, and develop a budget also. One of the goals I have identified is to develop as much HP and Torque as I can without going the forced induction route. Supercharger packages are quite expensive beginning around $6500. Not to mention the cost of the additional changes that will have to be made either way. As for the rest of the engine, the short answer is yes. I know that to realize any improvement in the induction side, there also has to be improvements made to the exhaust side. I am also considering changing the cams. And all these changes are going to require custom tunes. Then comes the cost benefit analysis, finding the biggest bang for the buck. Do I want this to be an all out race build? No, I am mostly looking for a streetable performance build. But, I don't want to blow my fuel mileage out of the water either.

Now for the information I found. I looked through the Ford Racing Catalog, and spent some time on their website too.

Cobra Jet Compatible Throttle Bodies:

As you mentioned there are three throttle bodies compatible with the Cobra Jet Intake.

M-9926-MSVT: Stock GT500 throttle body, tech notes indicate 60mm bores, 120mm total? No CFM rating mentioned.

M-9926-CJ65: Upgrade from stock MSVT, with two 65mm bores, 130mm total? CFM rated at 1517cfm.

M-9926-SCJ: No mm size is mentioned in the tech notes for this TB. CFM rated at 1797cfm.

Height Measurements:

It appears I was looking at package demensions, not actual demensions of the manifold. The assumption that the Cobra Jet intake appears shorter is likely incorrect.


Thanks,

 

What RPM band do you want to build power?

In other words, are you wanting to improve towing capability, make the truck boogie 0-60 mph, or are you going for a higher speed 1/4 mile racer? All three of those examples would use different cams and intakes.

 

Hi QwkTrip,

My goal is to develop as much HP and torq as possible and retain streetability. I think the best RPM band for what I am looking for is 1500-4500 RPMs, with peaks near 3000. I am not looking to build a 1/4 mile racer out of this truck, that is what my 67 Firebird is for...

 

I'd suggest the following in the order given, as budget allows.

* headers, exhaust, intake, throttle body
* camshaft swap
* Rear suspension work to stop the wheel hop
* stall converter
* ported heads

It's assumed that you should have a proper tune at any level. Also, what gears do you have?
No matter what you do it is essential to set the stage for air flow in and out of the engine.

 

I'm a Chevy LSx guy, so I quickly searched a few things about the 5.0L Coyote. Looks like the heads flow just shy of 300 CFM at 0.5 inch lift on the intake side. That's a good cylinder head for stock. Exhaust flow is good too. Overall it looks to come in just shy of GM LS3 heads which are proven performers. That's going to lend itself to great results with a cam swap. I also notice the heads take well to porting, pretty much the same way as GM LS3 heads. Perhaps even a little better on the exhaust side. All I can say is, it's about damn time Ford made an engine that could compete with what GM did in 1997. It looks like Ford guys can now have fun without needing forced induction.

However, the Coyote throttle body is only 80mm. That's even smaller than a stock Chevy 5.3L throttle body at 85mm. I'd definitely suggest going with 90mm throttle body since 80mm is too small for what you want to do.

Injectors are rated about 33 lbs/hr. That's sufficient to support all the mods I suggested, until you get to the ported cylinder heads. It's going to be iffy at that point whether the fuel system can support but I would look at the duty cycle on the injectors and see if you need more injector. It's best to run injectors below 80% duty cycle.

By the way, I have a Firebird too! Right now I'm doing a 427 LSx swap with 6-speed manual. It would be a pretty darn fast car if it wasn't for the manual transmission. But I'm going for smiles per mile, not quarter mile. And the manual trans combined with a serious thumpin' idle lope will do the job just fine!

 

The bigger you go on cams, short runner intake manilfolds will move your power band much higher than the 1500 to 4000 that you are looking to use. The intake is made for top end power in a Mustang and not a wide torque band needed for a 6K pound truck.

 

So you are saying the 5.0 is only comparable to an LS1 from 1997? LOL!!!!!!!!!!!!!!

 

My point was that GM left Ford in the dust in 1997 with the introduction of the LS1 and the gap just got bigger over the years as GM kept improving the engine family. The only thing a Mustang owner could do to keep up is use nitrous or boost, or put an LSx in their car (which many have done). It has taken Ford a decade to do something about it. Terribly slow response. The Coyote and larger 6.2L are nice engines. My criticism is, it's about damn time.

 

To me the reason why GM was putting more power out all of those years is ford was developing new technology. Ford went from pushrods to overhead cams. And in the end the 4.6 ended up being a pretty good motor, parts cost more because of the technology but they came a long way. Not sure why GM refuses to make an overhead cam V8. I have read that they had hell trying to design the new corvette motor with direct injection because it is harder to do on a pushrod motor.