head questions

[shadow9]

What are the pros and cons of each head? Not sure weather to go with the bathtub head or the fast burn. how does each one flow? affect compression? valve clearence? etc. I searched but didnt find much about the specifics about each head.
btw this is for circle track purposes so i'm looking for tourqe more than anything but top end also comes into play.
thanks in advance

[tvanlant]

Thedodgegarage.com does a decent job of explaining. Here is a basic rundown:

G head flows about 10% more stock than a swirl, but the swirl makes more low end torqe and better response. With TII pistons, the G head will be around 7.8:1 CR, while the swirl is 8.1:1. Ported, both heads respond nicely. The valves in the two heads cannot be swapped because of different stem heights. I prefer the swirl head because of the higher compression, and the swirl effect in the combustion. If you have a cal for a swirl, it is not best to swap to G head without a recal, and vice versa. Both heads are non-interferance, so don't worry about valve clearance.
For a dirt burner, the swirl makes the torqe and the response, but the G head will flow more in the RPM and make a little more top HP. A good ported swirl would be great because it still makes the torque and can flow some high RPM also.

[allmotor]

absolutley the G head is the BEST!!!! I spent over 40 hours flow benching every 2.2/2.5 head. hands down the G head was the best followed by the 1981-1983 head. the 782 head was the worst POS for flow. It is easy to obtain over 250hp on these engines. the whole key to making power is the cam profile. I have used nothing but Schneider or Isky cams. my 2.2 generated over 325hp @ 6800. Running an Isky cam with .596" lift, 103 lobe center. dur 268°@.050"

[turbovanman]

Quote:

Originally Posted by tvanlant Thedodgegarage.com does a decent job of explaining. Here is a basic rundown: G head flows about 10% more stock than a swirl, but the swirl makes more low end torqe and better response. With TII pistons, the G head will be around 7.8:1 CR, while the swirl is 8.1:1. Ported, both heads respond nicely. The valves in the two heads cannot be swapped because of different stem heights. I prefer the swirl head because of the higher compression, and the swirl effect in the combustion. If you have a cal for a swirl, it is not best to swap to G head without a recal, and vice versa. Both heads are non-interferance, so don't worry about valve clearance. For a dirt burner, the swirl makes the torqe and the response, but the G head will flow more in the RPM and make a little more top HP. A good ported swirl would be great because it still makes the torque and can flow some high RPM also.

I would assume he's talking N/A so those compression ratio's are too low.

[allmotor]

low end torque is really not an issue in circle track, because you should never be below 4000 rpm. My engines were running 13-14½:1 compression ratio.

[shadow9]

I'm not to worried about compression, i have a crazy idea for the bottom end, see my post in the engine block forum.
I was more concerned about flow and such and the cams for it, I'd like to stick with OEM stuff to stay within the rules, but i can interchange all i want, I hear the cam from a 2.2 turbo 2 car is the best OEM cam for my aplication but with it being a turbo cam would i have to run it a tooth back or something?
thanks

[turbovanman]

TBI cams are the best, turbo cams are limited in lift and duration. For rollers, the 88 TBI is the largest one.

[shadow9]

I always thought so to but Roger Thomson lives just down the street from me and thats what he said to do and when it comes to mopar he knows his stuff as u probly know.. just curious the theory behind his logic... not doubting you just saying were i got my info from, everyone else says TBI cams are best as
well.

Also I was thinking about valve springs, and woudl it be just as simple as taking the springs out and reinstaling them with washers underneath? it would stiffen them up pretty good and maybe get me a little more in the top end, the car really seems to fall off around 5500 and i make it up to 6000 to maybe 65000 RPM if i'm really moving but mostly around 6200.
What else would be restricting power up in that RPM range taht i coudl improve on?

[turbovanman]

Try advancing the timing, your not going to get any more power using a turbo grind.

Magnum 318 springs are a cheap upgrade and have some nice spring pressures, check out the PT lifter thread-labeld Conical valve springs.