Head work with cam swap

[BlaqWhole]

I'm planning on doing ported heads before I do a cam. In fact, I'm gonna do the head swap myself. If you send your heads in, you can get ported heads for less than $1,000. Otherwise you are looking at around $1400-$1700. And aftermarket heads will run around $2500. TSP has them for $899 when you send yours in. Not sure what the wait time is. And you're looking at about a 20 hp gain. Forced induction will get you even more of a gain. At $900, that is the exact same as LT headers from a top tier company. Well worth it if you ask me.

Originally Posted by Jason 98 TA

We do the cnc porting for guys a lot when they do the cam swaps. its well under a grand & adds 25hp. While your there its hard not to bolt on another 25

Jason, I personally would like some more info. How much and what kind of porting? Do you upgrade or change the valves and/or springs? If not then how much extra to do all that? Thanks for any info!

[hunter1660]

What about shaving the heads and increasing the compression? Is there clearance for this?Thats the head work I'd want.

[VADER SS L99]

Originally Posted by 132SS

Just wondering if out of everyone thats done or is doing a cam swap how many rework the heads? Im pretty new to sports cars and doing any kind of engine upgrades but is port and polishing the heads gonna net me any benefits with my cam swap. I know when you do the cam you replace the springs and such but who is going further and what is the cost. Thanks

If you are a L99 I highly recommend it. If you are a LS3 then there are other parts of the car that I would spend the money.

[Orange Crush 1LE]

I think it really comes down to budget and your goals. For those that have the budget and are going for max numbers, doing heads may make sense. It didn't make sense for me in my quest for a road course ringer, as I wanted to spread my investment out on engine mods, suspension, track tires and wheels, and now am adding aero improvements. But for a drag racer, sure heads may make sense if budget permits.

[LS3 SS]

Originally Posted by hunter1660

What about shaving the heads and increasing the compression? Is there clearance for this?Thats the head work I'd want.

I'm sure Litle88 will chime in here, but you have to be careful with LS3 heads, because your PTV clearance is limited when you step up in cam profile. You have to be careful because the deck height on the LS3 heads isn't the tallest for milling, and the valve angle makes it hard to mill aggressively. With that said, every setup is different. You also have to factor in the lift numbers of your cam, and the LSA, and then actually measure for clearance with the heads installed. If you mill too far, you can probably expect to be replacing some valvetrain components.


I actually bought some PRC 255cc heads and paid 2100$ for them, but they were milled to 66cc and have a 13 degree valve angle for aggressive milling. I should find out my results on Friday, to see how much gain I received from ported/milled aftermarket heads.

[MikeOD]

Originally Posted by hunter1660

What about shaving the heads and increasing the compression? Is there clearance for this?Thats the head work I'd want.

My heads are milled...the piston to valve clearance isn't bad at all if you aren't going bananas with the cam...if it's a daily driver, I wouldn't recommend that anyways unless you like changing valvesprings all the time.

You can also change to a different head gasket...stock gasket is 0.059" thick, and every LS3 I've measured has the pistons coming 0.010 out of the hole...giving you 0.049" quench height...you could run a thinner gasket and bring the quench down to ~0.038-0.042" if you go to something from Cometic.

[litle88]

Yes Ls3/92/99 heads flow very good. BUT they could be better, L99 owners benefit because we are at a compression and parasitic disadvantage compared to Ls3'd already.

The power you want has lots to do with the HEADS plain an simple, ~8/900 dollars for 25hp NA is awesome and these heavy azz cars need every bit.

Yes there are clown shops out there that are clueless, you get what you pay for.
The shops I'd send my heads for cnc'ing are
• TSP
• TEA
• WCCH
• LPE
• AI
• flowtech
In no particular order ALL are awesome in their own right.

Is it worth it? Yes
Do you just absolutely have to have it when you do a cam? No not really, you can budget it for later BUT if your an L99 getting a cam, then WAIT til you can do both cause the heads need to come off, you won't regret it. Jeff is at 465hp in an AUTO and those are very good numbers.
MikeOD has 500! With a small cam
It's worth it!
Just my .2

[14pilot]

If you have budget get TF 235s.

[litle88]

Originally Posted by 14pilot

If you have budget get TF 235s.

He meant TFS 255's they are the only model for rectangular port heads from TFS. They are not a GM cast they are totally different with a different valve angle for better PTV clearances for more compression with bigger cams like TSP's and MAST.

[14pilot]

Originally Posted by litle88

He meant TFS 255's they are the only model for rectangular port heads from TFS. They are not a GM cast they are totally different with a different valve angle for better PTV clearances for more compression with bigger cams like TSP's and MAST.

Thanks for the correction.

The 255s are indeed the 821 casting replacement.

And back to that big budget, order your 255s from TEA with their CNC porting.

[litle88]

Originally Posted by 14pilot

Thanks for the correction.

The 255s are indeed the 821 casting replacement.

And back to that big budget, order your 255s from TEA with their CNC porting.

Lol I got ya pilot! I knew what you meant, I got fat fingers too. Just didn't want a know it all corrector to do it rudely.

Yes! How about those heads? I'm curious to see the type of cam these heads like.

[Kelly@PCMofNC]

I'm with litle, it's definitely worth it. I've never ever added ported heads and lost power, but then again I use Advanced Induction and West Coast Cylinder Heads - those guys are the top of their game.

You will get to a point with your modding where the hp doesn't come so easy and cheap (same thing with ET at the track...the faster you go the harder it is to whittle down those tenths). So no, the $995 AI charges for porting that nets you 25rwhp is costing $39/hp and isn't as much of a bang for the buck as a cam swap (~$800 parts) that nets you 60 rwhp at $13/hp but at that point, you're out of the 'cheap power' options (minus n20).

[MikeOD]

Originally Posted by litle88

Yes Ls3/92/99 heads flow very good. BUT they could be better, L99 owners benefit because we are at a compression and parasitic disadvantage compared to Ls3'd already.

The power you want has lots to do with the HEADS plain an simple, ~8/900 dollars for 25hp NA is awesome and these heavy azz cars need every bit.

Yes there are clown shops out there that are clueless, you get what you pay for.
The shops I'd send my heads for cnc'ing are
• TSP
• TEA
• WCCH
• LPE
• AI
• flowtech
In no particular order ALL are awesome in their own right.

Is it worth it? Yes
Do you just absolutely have to have it when you do a cam? No not really, you can budget it for later BUT if your an L99 getting a cam, then WAIT til you can do both cause the heads need to come off, you won't regret it. Jeff is at 465hp in an AUTO and those are very good numbers.
MikeOD has 500! With a small cam
It's worth it!
Just my .2

I've considered putting a bigger cam in this setup to see what it's really made of on the stock bottom end...but I want WAY MORE than that can give me...so I'm going to pull the engine and put it in a plastic bag...turbos > heads/cam and forged 370 > stock 376

[Pro Stock John]

Originally Posted by Jason 98 TA

We do the cnc porting for guys a lot when they do the cam swaps. its well under a grand & adds 25hp. While your there its hard not to bolt on another 25

Jason old friend,

You've tested a lot of cams and combinations over the years.

So if someone was an L99'er like me thinking about heads and cam, what would you reccomend? As a drag racer I'm mostly interested in usable power, not recording setting peak numbers.

Milled heads?