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Discussion Starter #1
I am looking to build a dart 363 shortblock after blowing up my 347 at a track day. The car currently has a trick flow R long runner manifold and 75mm TB. Build is planned to be 363, 10.5:1 comp ratio, afr220 or high port 225 heads, ~7k rpm shifts. Car is used 50% street, 40% track days, 10% drag strip.

I'm wondering if I should buy just the box r plenum and 90mm TB, or sell the whole intake and current TB and go super vic EFI with a 4150 throttle body. Has anyone used both? I've found some flow numbers from tmoss, it looks like the box R flows about 320cfm ported. 8.2 Super vic looks like maybe it flows that out of the box but usually requires machining to align with the heads.
 

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I dunno. I have both on my two cars right now. Ed Curtis is doing a cam for the 363 SV car, and the first thing he said was ditch it for a Box R. My 331 has the Box R with his cam. Driveability is a little better, and I tune them myself. However, it may not be a fair comparison. We'll see when I get his cam for the SV car. I turned him down. The SV + elbow fits under my stock hood, and I like how clean it looks. The Box R will not fit under the stock hood.
 

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Discussion Starter #3
I agree the SV combo looks much better plus would drop a few pounds. I have a cowl hood already and there is a 1" spacer between the upper and lower to clear the valve covers for roller rockers. I have seen a lot of people with clearance issues though with the box in the front or by the throttle body. It's interesting Ed said to go with the box R, that's a pretty good endorsement.
 

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What rpm are you shifting at on the 331?

I dunno. I have both on my two cars right now. Ed Curtis is doing a cam for the 363 SV car, and the first thing he said was ditch it for a Box R. My 331 has the Box R with his cam. Driveability is a little better, and I tune them myself. However, it may not be a fair comparison. We'll see when I get his cam for the SV car. I turned him down. The SV + elbow fits under my stock hood, and I like how clean it looks. The Box R will not fit under the stock hood.
 

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Hi Tom,

When I built it back in 2008-2010, I told Ed I wanted to shift it at 7k. I have run it out to 7,200 or so, but I think it falls off between 6500-7000, but I don't have a dyno there to confirm. I'll bet the optimum shift point is below 7k. Some day soon, I'll probably use one of my logs to compute the power curve. It's a manual, so the shifts come fast and it's hard to be precise.

Chris
 

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Discussion Starter #8
Tom,

Do you have a preference for one of these intakes over the other? Out of the box vs after you've worked them?
 

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Man. Moving from the 347 to the 363 is a tough one. Keeping same parts you should have 15 ftlbs everywhere. It’s the small increase that makes it hard to purchase new parts for.
personally I would get a different cam from FTI to match your new setup. ask Ed what intake. The RPM you want to shift at will determine what intake you want to use.
 

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Tom,

Do you have a preference for one of these intakes over the other? Out of the box vs after you've worked them?
I get enough info on the engine/drive train and what the owner wants to do with it. Intake choice then follows if I am involved in choice - often guys have what they want already and as long as it isn't too far off, I let them know and work with them. Parts chosen for assembly and intended use (rpm band) have a significant impact on choice. Sometimes they can be used stock and sometimes I'd recommend porting. I recommend work on long runner intakes probably more, but it still comes down to what I said previously.
 

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I debated about using this example, but after re-reading these conversations I think I will as it address' the questions of the OP and Fast Driver. My guess is that Ed may have recommended going Box R over the SV because it has about 3" of added runner length with less taper. Sometimes that makes all the difference as does the cross section of the intake. Peak HP numbers are nice to talk about, but average torque in the usable rpm range is what gets there first. So, as the cam designer I would try to take Ed's advice. Added runner length may trim some peak but it may beef up the mid range torque more than enough and be the best choice.

Fastdriver has a blower 331 that sifts 6,500-7,000 rpm and is a manual using a Box R intake. I worked with a "local" racer years ago who ran a blown 331 making 847 WHP @ 6,600 rpm & 12psi running AFR 205 heads, a fully ported RPM1 intake that flowed 20 cfm less than the head and a powerglide that shifted in that same rpm range as Fastdriver's and ran 8's. Like any racer, he looked for more and switched to a Box R then had it tuned. It made more peak power but barely put up the numbers that the RPM did. After tuning and working to get back to where he was, he decided to put the RPM back on and went quicker/faster than ever. Moral of the story is because his combination was more optimally tuned for his automatic, the "better" R intake turned out not to be the best choice. The R has 9.75" of runner length and a larger cross section than the RPM's which has 12.5" of runner length. The mid range of the RPM was so strong against that converter that the R could just not compete. So, sometimes you don't know for sure until you TRY something. Fastdriver may want to consider, as an experiment, using an intake with more runner length despite having a stick car vs my example's auto.
 

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Both of my cars run a 76mm turbo. Not sure if that makes any difference in your analysis. It seems to me that turbo cars can benefit with a stronger mid-range that might help get the turbo spooling a little quicker, too.

I'd like to try out the various intakes on that car in the future. I might take you up on that one, Tom. If an RPM is going on it, I'd want it ported, though. I'll reach out to you when/if the time comes.
 

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I am looking to build a dart 363 shortblock after blowing up my 347 at a track day. The car currently has a trick flow R long runner manifold and 75mm TB. Build is planned to be 363, 10.5:1 comp ratio, afr220 or high port 225 heads, ~7k rpm shifts. Car is used 50% street, 40% track days, 10% drag strip.

I'm wondering if I should buy just the box r plenum and 90mm TB, or sell the whole intake and current TB and go super vic EFI with a 4150 throttle body. Has anyone used both? I've found some flow numbers from tmoss, it looks like the box R flows about 320cfm ported. 8.2 Super vic looks like maybe it flows that out of the box but usually requires machining to align with the heads.
I'm in the process of choosing a set of heads for a SBF stroker as well. Have you decided between the AFR 220s or 225 high ports yet? If so, what was the deciding factor for you? Were the 205 11Rs ever on your radar?
 

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Thought I would come back and share another dyno test of a Dart based 363, Twin turbo, custom solid roller, AFR 205 or 220 heads (they didn't specify) where they did a comparison between a Super Victor and a Victor EFI intake. I've seen guys diss this design because it has a turn - but keep in mind that happens in the plenum. They are no slouch and no joke. They were both stock, so there was more in them both.
 

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Thought I would come back and share another dyno test of a Dart based 363, Twin turbo, custom solid roller, AFR 205 or 220 heads (they didn't specify) where they did a comparison between a Super Victor and a Victor EFI intake. I've seen guys diss this design because it has a turn - but keep in mind that happens in the plenum. They are no slouch and no joke. They were both stock, so there was more in them both.
Only shows about a 1000 rpm band though. What was it like below 5400 rpm?
 

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