Indy SR heads what intake???

[DJF]

Hello all,

I rebuilt my 440 motor last year and only managed a maximum of 375 hp at the wheels. Reading around I see the Single plane intake Manifolds seems to work wonder I belive Ron was taking about a Mopar M-1 intake? My question is will this or will a Edelbrock Super victor fit my Indy SR heads and will this give me a noticable increase over my indy dual plane?

850 Might demon Carb
10.5:1 static Compresssion
Ported SR heads
Ported Dual Plane intake
Comp 511 511 cam


Many Thanks
Daryl

[firefighter3931]

The ICH dual plane moves plenty of air and is a great dual purpose street/strip manifold. A single plane will reduce bottom end power and off idle throttle response as compared to a dual plane. The DP is not the reason for your lower HP results, inmo....the cam profile is likely the problem. 

Some chassis dyno's will read lower than others so you can't allways take the results as gospel....Mustang Dyno's are notorious for reading low. Sometimes a high stall torque converter will skew the results as well. 



Ron

[DJF]

ahh just the man,

Thanks for the reply.

The Cam specs are :-

Grind CRB-5209-5209-H108

Gross Value Lift Intake (0.511) Exhaust (0.511)

Duration @ .050    Intake (246) Exhaust (246)
Lobe Lift              Intake (.3410) Exhaust (0.3410)
Lobe separation 108.0

The dyno was a dynodymanics, torque convertor is a tci 3000rpm stall

also i dropped 10hp by removing a carb spacer to try and get more hood clearence the power drop was instant over 5500 rpm with the spacer it made increasing power right up to 6200 rpm

Whats your thoughts?

[oldschool]

you cant go wrong with a indy dualplane for a street car.i have four of them.on my 500"motors they make about 700 hp. i just dynoed one on a bigger motor and it made 759 hp.not bad for a dualplane.

[firefighter3931]

also i dropped 10hp by removing a carb spacer to try and get more hood clearence the power drop was instant over 5500 rpm with the spacer it made increasing power right up to 6200 rpm

Whats your thoughts?

That's interesting....basicly the engine is responding to increased plenum volume and wants more air up top.  A single plane might let more air in but it will also reduce torque....so there is a trade-off. I guess you need to ask yourself what is more important....low end throttle response or top end charge. 


I'm still thinking that the slow ramp cam is hurting your peak power somewhat, if not significantly. I specced out a build similar to yours for VegasMike and his made 525hp/540tq at the crank. He's running the Comp XS282S extreme energy solid. His build is in the proven combo's section complete with dyno numbers/graphs.


Inmo, you need more lift to access the flow from those heads....the duration is where you need it to be with that stall.



Ron

[DJF]

i see,

ok so im looking at the lift of that cam you mentioned 0.347 on the intake 0.361 on the exhause it doesnt look greatly different from what I have or am i underestimating the change that will make. If this was your motor what cam would you have in it? its a street/strip car with 3.73 rear end.

Am i searching for somthing extra that isnt there?
I really need to see off this 2005 Supercharged mustang as welll 
Im not goin up against it till mid september

[firefighter3931]

i see,

ok so im looking at the lift of that cam you mentioned 0.347 on the intake 0.361 on the exhause it doesnt look greatly different from what I have or am i underestimating the change that will make. If this was your motor what cam would you have in it? its a street/strip car with 3.73 rear end.

Am i searching for somthing extra that isnt there?
I really need to see off this 2005 Supercharged mustang as welll 
Im not goin up against it till mid september

The Comp XE solid grinds have a more agressive ramp speed which increases power. One of our members is running the XS282S and has been as fast as 11.30's in his 71 Roadrunner....it's a great cam. I like the solid lifter for valvetrain stability....hyd cams start to drop off in power above 5500-5600 due to lifter collapse and valve float.


With a 3k stall and 3.73's i would use the XS282S and a set of EDM lifters. 

There is definately more power available. What was done to your SR's ? Any valve work or porting ? If the heads were installed out of the box there is a lot of power left on the table. 



Ron

[DJF]

ahh thats a great help thanks!!! 

Yeah I had Indy fully cnc port these heads before they were shipped and the intake to match. Im using Indy roller rockers 1.5 ratio as there was no way my old comp rockers were ever gonna work properly, they guys at indy said they would but after trying and haveing all kinds of shims I couldnt see these lining up not without maching lumps off them.

so its a new cam in order, new lifters. does that cam come with the solid lifters or is it available in a kit do you know? Im gonna need more push rods again i guess and i play that cut them down game.

Also will the spings supplied with these heads be ok for that cam?

[firefighter3931]

ahh thats a great help thanks!!! 

Yeah I had Indy fully cnc port these heads before they were shipped and the intake to match. Im using Indy roller rockers 1.5 ratio as there was no way my old comp rockers were ever gonna work properly, they guys at indy said they would but after trying and haveing all kinds of shims I couldnt see these lining up not without maching lumps off them.

so its a new cam in order, new lifters. does that cam come with the solid lifters or is it available in a kit do you know? Im gonna need more push rods again i guess and i play that cut them down game.

Also will the spings supplied with these heads be ok for that cam?

The springs and rockers are fine....no worries. You will need to order the pushrods but i would wait until the cam is installed and get a checking pushrod to measure for correct length. With CNC porting you should be making a LOT more power than you are currently....you need a cam to access that high lift flow area.   

Order the cam through Dwayne at Porter Racing Heads...he knows the Comp line very well and is a distributor for them. He will also get the correct EDM lifters for you so there will be no screwups. He might come up with something better (custom grind) so make sure to outline your combo with him and ask for recommendations. 

Porter Racing Heads 802-951-1955



Ron

[DJF]

Awesome!!!

I figured somthing was wrong here, thanks for clearing that up. I will give Dwane a call and get this thing running like it should! Thanks very much fo the help and advise i really appreciate it :-)

[firefighter3931]

Awesome!!!

I figured somthing was wrong here, thanks for clearing that up. I will give Dwane a call and get this thing running like it should! Thanks very much fo the help and advise i really appreciate it :-)

Keep us posted Daryl....i see lots of tire smoke in your future. 

Once this puppy is dialed in you'll be posting in the suspension/chassis forum looking for ways to make the beast hook. 


Ron