Head work. When to do it?

[Viper Beau]

I noticed in my reading of some of the threads that some of you guys don't recommend doing head work with certain applications, i.e. s/c. Just wanted to know from those guys who build and have had motors rebuilt your thoughts on when to do head work and when not to. My reason for the question is I am torn between a NOS setup or a s/c. I do plan to forge the pistons, rods, and do billet mains (800hp, give or take). Where will head work come into play?

FYI, I am not as versed in the mechanical lingo so please dumb your answers down for the mechanically impaired.

 

[TNVIPER]

Dont do the heads until you know what direction you are taking....heads used with a blower need different work than heads N/A.............also remember that if you put a blower on then later have the heads done you will need to have the truck retuned....best to do the major mods at one time and save $$ on retunes..

 

[yellowfever#154]

You want head work when:

1. Turbos
2. Naturally aspirated high hp build (Stryker heads are then a better option)
3. Big belt driven superchargers (ie. F2 Procharger from JMBJustin)
4. ROE superchargers using high boost pulleys
5. NOS specific builds

Dont do head work with:

1. Paxton systems
2. ROE superchargers with low boost pulleys

 

[Tooloe]

I would go n20 unless your mr money bags... i fully built my motor Rods,pistons,head work, and a 150 shot and it made 786 and i could run a bigger shot if i dare

 

[LoveThisTruck]

I didn't touch my heads at all when I did my build. I just wanted to be safe and make decent power (around 650)... I figured why spend an extra 2-3k for 20-30 extra HP:dontknow:

But it all depends on what power adder you go with. For a Paxton or Roe, it's not worth it IMHO

.

 

[rottenronnie]

I noticed in my reading of some of the threads that some of you guys don't recommend doing head work with certain applications, i.e. s/c. Just wanted to know from those guys who build and have had motors rebuilt your thoughts on when to do head work and when not to. My reason for the question is I am torn between a NOS setup or a s/c. I do plan to forge the pistons, rods, and do billet mains (800hp, give or take). Where will head work come into play?

FYI, I am not as versed in the mechanical lingo so please dumb your answers down for the mechanically impaired.

If you are going with a typical street-style (low volume) forced induction system, a worthwhile and cheap mod is to back-cut the valves in your stock heads. This is something you CAN do without worrying about losing boost pressure.

The lower capacity blowers lack the ability to maintain boost pressure once you open up a "hole" at the other end by doing more radical head mods. I.O.W. the column of air that used to back up and create boost pressure now flows through the engine and the blower can't keep up (not enough capacity). You can compensate to a point by increasing boost but you will rapidly reach a point where heat (among other things) becomes an issue because you are going outside of the blowers intended use range.

Options for big power (say the 1000 and up range) (aside from Nitrous):
1. *Big Head Flow combined with Big Capacity Blowers = Big Power.
2. HUGE capacity cylinder heads WITHOUT a blower of any kind (or any nitrous) can also = Big Power. BUT COSTLY and not practical for the trucks.

*The first option gives you more usable power for a street style vehicle.
The 2nd option can really confuse people that went with option #1.

Another route to go for a more usable power plan (Under 1000 HP): Go with Strikers and a cam and hit it with a big shot of nitrous anytime you want; as it sounds like you want to go with stronger internals anyway.

Or another route- Strikers, cam turbo and nitrous.

Ronnie

 

[cyalata]

I noticed in my reading of some of the threads that some of you guys don't recommend doing head work with certain applications, i.e. s/c. Just wanted to know from those guys who build and have had motors rebuilt your thoughts on when to do head work and when not to. My reason for the question is I am torn between a NOS setup or a s/c. I do plan to forge the pistons, rods, and do billet mains (800hp, give or take). Where will head work come into play?

FYI, I am not as versed in the mechanical lingo so please dumb your answers down for the mechanically impaired.

ive been wondering the same thing i jus went the route of order a billet crankshaft and next will be billet mains forged pistons and rods and a comp cam im always runnin a roe s/c soon to be switched to the 10lb pulley so i might do head work all depends on what the boss says:dontknow:

 

[SRT10VENOMOUS]

heads are always good na or otherwise.. more air in = more power.. simple...

 

[Viper Beau]

Just wanted to thank you guys for the input. Tooloe, I think I will go your suggested route as I am not Mr. Money bags. Just want a street and occassional strip setup with NOS to murder these ricer punks and mustang guys around Tampa. Since the engine is apart it sounds like I could do some moderate head work and that would benefit me on the NOS setup. In addition to that, I noticed some of you guys didn't see much power gain if the block was overbored by .10 without head work. It seemed to be that if you are going to overbore, don't do more than .10, and head work seemed a must if I wanted to appreciate a decent power benefit. Let me know if I am not understanding that correctly.

I would like to ask you guys if you have experience or know others using bigger NOS shots, i.e. greather than 150, WITH a FORGED engine and what kind of hp and trq. numbers you see at those different shot levels. Finally, what piston, rod, and billet main combo are you guys recommending for staying in the 700 - 800hp range. I am assuming to get those hp numbers my NOS shot will be 200+. Since I am pretty much convinced to go with the NOS setup I would appreciate any suggestions on what you guys would do in my scenario having the motor open and wanting 800hp (more or less). Thanks.

 

[ARRESTmeRed04]

might looking to raising the compression ratio a little bit while you got it apart, tooloe's engine made something like 505hp/530tq at the wheels then with a 175 shot it spun the tires on the dyno but it was 786tq....get in touch with JMB about the nitrous he can point you in the right direction

 

[VIPER]

I would go n20 unless your mr money bags... i fully built my motor Rods,pistons,head work, and a 150 shot and it made 786 and i could run a bigger shot if i dare

whimp


im running 175 - 300 shot on a built motor

make sure you get a tune if ur going to run NOS.....

 

[Tooloe]

whimp


im running 175 - 300 shot on a built motor

make sure you get a tune if ur going to run NOS.....

already tuned bubba.. and it's built for alot bigger shot it'll make 800 give me until i get a new clutch lol

 

[LoveThisTruck]

already tuned bubba.. and it's built for alot bigger shot it'll make 800 give me until i get a new clutch lol

Sounds like a ricer excuse to me