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Question about the Comp Xtreme Energy solid roller XR286R
248/254 @50 614/621

In a 393W with 10.8:1 compression, AFR 185 heads, Victor Jr intake, a Holley 950hp, and 1 3/4 headers.

I was wondering at what RPM would the HP and TQ peak at?
 

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Question about the Comp Xtreme Energy solid roller XR286R
248/254 @50 614/621

In a 393W with 10.8:1 compression, AFR 185 heads, Victor Jr intake, a Holley 950hp, and 1 3/4 headers.

I was wondering at what RPM would the HP and TQ peak at?
The "Cam Card" should have all that info. Look at Comp's websight and I'm sure you'll find that and more.

John

PS: Is this build a done deal? If not I'd consider stepping up on the heads to their 205's.
 

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Vr Jr is going to be a cork in your power output.
Sorry, but I disagree. I still say it's the heads. Vic Jr's are made for big power up high. Go with a higher flowing head and you'll be good. Call Comp and/or AFR and get their opinion.

John
 

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Sorry, but I disagree. I still say it's the heads. Vic Jr's are made for big power up high. Go with a higher flowing head and you'll be good. Call Comp and/or AFR and get their opinion.

John
Ever flow a intake attached to a head ? I have.
A VrJr on a ported set of DOOE heads only flows 190 CFM and that intake had the draft removed. The heads by themselves flowed 235 CFM.
That same intake on a ported Canfield head flowed 190 CFM the Canfield head flowed 360 CFM by itself.
The lift point at which each test reached the 190 CFM was diifferent. The DOOE heads it maxed out at .500 lift the Canfield head was at a lower lift point as the canfields flowed more at lower lift. but reached max flow at .700 lift.

The heads stated should already flow more than the intake will allow it to.
The cam OP states would have a high RPM peaky tork curve.
 

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Question about the Comp Xtreme Energy solid roller XR286R
248/254 @50 614/621

In a 393W with 10.8:1 compression, AFR 185 heads, Victor Jr intake, a Holley 950hp, and 1 3/4 headers.

I was wondering at what RPM would the HP and TQ peak at?
I ran practically the same setup a couple of years ago with the only difference being I used AFR 205's. 3400lb race weight, 4 speed, and 4.11 gears. The motor liked best to be shifted at 6400. Anymore rpm and it went slower. Never had it on a dyno. The performance was reliable and repeatable week after week at the track.
 

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Ever flow a intake attached to a head ? I have.
A VrJr on a ported set of DOOE heads only flows 190 CFM and that intake had the draft removed. The heads by themselves flowed 235 CFM.
That same intake on a ported Canfield head flowed 190 CFM the Canfield head flowed 360 CFM by itself.
The lift point at which each test reached the 190 CFM was diifferent. The DOOE heads it maxed out at .500 lift the Canfield head was at a lower lift point as the canfields flowed more at lower lift. but reached max flow at .700 lift.

The heads stated should already flow more than the intake will allow it to.
The cam OP states would have a high RPM peaky tork curve.
I wonder how much the 9.5" deck / 351w version of the Vic Jr flows compared to the 8.2" deck version.

My box stock 8.2 deck Vic Jr flowed around 250 cfm on my guy's bench by itself. My Parker Funnel Web was right around 300 cfm by itself on the same bench. Did not flow them attached to the head because I was not going to spend the money to have a port developed for an intake and my heads for my street/strip 289.
 

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In most isntances I would port a set of heads. Then attach a intake flow the good ports and bad ports of the intake. Then start porting a good runner and bad runner of the intake to get the most ot of it attached to the heads as a base line. I would then free flow the intakes ported runners and try to get the flow as even as possible with the rest free flowed. I would also try to match the good ports flow with the bad runner.
I might get a bad runner up 30 CFM if a good runner was un ported already 15 CFM better than the bad port Only needed to pull 15 more CFM to match up the air flow. I could possibly have gotten 40 CFM better out of the good runner but the engine would have different flow availabe to each cyl.

Most cast aluminum intake your lucky to get within 20 to 30 CFM of the head free flowed. Have done some sheet metal intake the flow the same very few sheet metal ones will increase the flow. Real PIA to build and flow them.
Short answer flow the intake to the heads not the heads to the intake.
Now knowing the flow of the intake bolted to the head gives info for a better cam selection.
 

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Question about the Comp Xtreme Energy solid roller XR286R
248/254 @50 614/621

In a 393W with 10.8:1 compression, AFR 185 heads, Victor Jr intake, a Holley 950hp, and 1 3/4 headers.

I was wondering at what RPM would the HP and TQ peak at?
not knowing the lobe separation, etc, I'm going to guess it should be all done by 6200, BUT it will be one heck of a torquey powerplant. I say peak HP at approx 5600-5800 and torque peak probably somewhere around 5000-ish.

Just a guess by the way. Hope it's close :)
 
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