Port and Polish or Cam

[darkz711]

I am looking into probably getting ported and polished heads or getting a cc306 cam. Im leaning more towards the cam upgrade because its about a third of the cost. Which will i see a greater gain out of though?

[tclelland]

TTT. Not to hijack dark711's thread, but I am looking for this answer as well.
A local race car engine builder named Ray Barton Racing quoted me +/- $2800.00 to do a port and polish on my heads, a cam and 1.6 rr. Wat cha think??

[azkkn]

I am looking into probably getting ported and polished heads or getting a cc306 cam. Im leaning more towards the cam upgrade because its about a third of the cost. Which will i see a greater gain out of though?

depending on your goals for the car, you are better off to do the cam now, but also keep in mind that a cam that will give you good power now, may not be the best one that goes with your mods down the road. porting and polishing a stock set of heads to me is a last ditch resort. you can get a very nice set of heads for the LT-1 in the aftermarket world, Like Air Flow Research. i bought the 210cc race heads and had enough custom things done to them right there at AFR when they were built that alone should have doubled the price(but it didnt). all total with the new heads, all the mods to them, the 1.6 RR's, and the stud girdles it came to right around $2800.oo. so to me spending $2000~$2500 on getting the stockers reworked is kind of a waste given the options. if you plan on doing a lot to this car, like a good power adder, say Nitrous, or a super charger, or even just making it a nasty N/A motor, my advice would be to start doing the small things first, like the fuel system, suspension, gears, exhaust W/ a good set of headers. then start piling up the stuff for the motor, making sure that every component will match the other as far as function. for instance you wouldnt want a cam with a lot of lobe over lap on a blower application, where as on an N/A car you would. When i crack a motor open, i have every thing i need just sitting there, i do it all at once , and am back on the road in short order. that way you have a kool pile of stuff to show your friends when they come over, if you change your mind, the cam you want to upgrade is still new in the box, not burried in the motor, and used, and can be sold on ebay or traded back in at the speed shop for the one you want.

[darkz711]

depending on your goals for the car, you are better off to do the cam now, but also keep in mind that a cam that will give you good power now, may not be the best one that goes with your mods down the road. porting and polishing a stock set of heads to me is a last ditch resort. you can get a very nice set of heads for the LT-1 in the aftermarket world, Like Air Flow Research. i bought the 210cc race heads and had enough custom things done to them right there at AFR when they were built that alone should have doubled the price(but it didnt). all total with the new heads, all the mods to them, the 1.6 RR's, and the stud girdles it came to right around $2800.oo. so to me spending $2000~$2500 on getting the stockers reworked is kind of a waste given the options. if you plan on doing a lot to this car, like a good power adder, say Nitrous, or a super charger, or even just making it a nasty N/A motor, my advice would be to start doing the small things first, like the fuel system, suspension, gears, exhaust W/ a good set of headers. then start piling up the stuff for the motor, making sure that every component will match the other as far as function. for instance you wouldnt want a cam with a lot of lobe over lap on a blower application, where as on an N/A car you would. When i crack a motor open, i have every thing i need just sitting there, i do it all at once , and am back on the road in short order. that way you have a kool pile of stuff to show your friends when they come over, if you change your mind, the cam you want to upgrade is still new in the box, not burried in the motor, and used, and can be sold on ebay or traded back in at the speed shop for the one you want.

what if i was gettting a pair of used stockers reworked for $700?

[Joe 1320]

In my opinion, LT-1s are begging for better heads. Even a backyard port job can give 20HP with no other changes. If you can get stock heads reworked for $700, I would do that before I put in a cam. I kinda chuckle at people who start trying to get more HP by changing only a cam. If the heads still don't flow any better do you think a cam is going to help? It may in some part of the powerband, but it still won't work really well. Also, if you are pulling the heads for a P&P you may aswell do the timing chain and cam while everything is apart. A cam is cheap compared to the rest of the stuff.

[N20LT4Bird]

In my opinion, LT-1s are begging for better heads. Even a backyard port job can give 20HP with no other changes. If you can get stock heads reworked for $700, I would do that before I put in a cam. I kinda chuckle at people who start trying to get more HP by changing only a cam. If the heads still don't flow any better do you think a cam is going to help? It may in some part of the powerband, but it still won't work really well. Also, if you are pulling the heads for a P&P you may aswell do the timing chain and cam while everything is apart. A cam is cheap compared to the rest of the stuff.

I agree with you here Joe1320 on doing the heads, that will be the biggest gain. However, I do think you will see some power out of the cam as well. You are absolutely right that if the heads are flowing as much as they can, the cam will not make any difference (just change where the power comes in), but thats assuming the flow through the heads is maxed out on the stock cam.

Joe (darkz), if you did BOTH, you would see some nice gains. From what ive heard the cc306 is a nice cam for a street car, even if you were to upgrade down the line. The cam would only be another few hundred bucks and if your pulling the heads - now is the time. Even if you have to save a little longer, I would recommend doing both at the same time.

Oh, and before you spend on the heads, make sure they are professionally ported on a flow bench. If the wrong guy gets ahold of them to port, they could end up not flowing as much as you hoped, or flowing worse. Get some flow numbers.

[darkz711]

I agree with you here Joe1320 on doing the heads, that will be the biggest gain. However, I do think you will see some power out of the cam as well. You are absolutely right that if the heads are flowing as much as they can, the cam will not make any difference (just change where the power comes in), but thats assuming the flow through the heads is maxed out on the stock cam.

Joe (darkz), if you did BOTH, you would see some nice gains. From what ive heard the cc306 is a nice cam for a street car, even if you were to upgrade down the line. The cam would only be another few hundred bucks and if your pulling the heads - now is the time. Even if you have to save a little longer, I would recommend doing both at the same time.

Oh, and before you spend on the heads, make sure they are professionally ported on a flow bench. If the wrong guy gets ahold of them to port, they could end up not flowing as much as you hoped, or flowing worse. Get some flow numbers.

lt1 heads 258/182@.500 and 248/191 @.600 complete with springs good to .600 lift
those are the numbers from the guy. The only thing i was skeptical about was that he said he couldn't find his flow chart. he still has to get back to me on the depression at which the bench marks were taken and he's going to post some pics for me.

[Squat13]

lt1 heads 258/182@.500 and 248/191 @.600 complete with springs good to .600 lift
those are the numbers from the guy. The only thing i was skeptical about was that he said he couldn't find his flow chart. he still has to get back to me on the depression at which the bench marks were taken and he's going to post some pics for me.

You may not want to hear it but go with AFR's. The Lt1 casting are great but they cand not be opened up to flow near the air a good set of aftermarkets will flow. And a set of AFR will most likly cost the same in the end as your port stockers because you for got about all the other stuff you need to run that cam.
YOur stock heads will need bigger Valves($$$), Bigger springs($$$), The spring bores in the head will need to be machined for the bigger spring, the head resurfaced and a valve job($$$), and thats BEFOR the port work which we all know is EXPENSIVE.
Now you could go to ebay and get a pair of complete AFR 190's for 1200$ and be good to go and flowing 25 or 30 more CFM than you will ever get with stockers. all you will need is gaskets.

[fastTa]

You may not want to hear it but go with AFR's. The Lt1 casting are great but they cand not be opened up to flow near the air a good set of aftermarkets will flow. And a set of AFR will most likly cost the same in the end as your port stockers because you for got about all the other stuff you need to run that cam.
YOur stock heads will need bigger Valves($$$), Bigger springs($$$), The spring bores in the head will need to be machined for the bigger spring, the head resurfaced and a valve job($$$), and thats BEFOR the port work which we all know is EXPENSIVE.
Now you could go to ebay and get a pair of complete AFR 190's for 1200$ and be good to go and flowing 25 or 30 more CFM than you will ever get with stockers. all you will need is gaskets.

Too many people get caught up in the blurred reality of head flow numbers specifically in relation to volume (CFM). The volume of air that a cylinder head can flow does not always equate to it's specific performance capabilities. The more important aspect to consider is the velocity characteristics of a cylinder head. Velocity is what makes real power due to the fact that velocity is what dictates how well the cylinder is "stuffed" to use lamens terms.

While it is true that the aftermarket ported LT1 castings tend to show better head flow numbers, it has been proven on the track and at the dyno that the stock LT1 castings when equally, ported can will usually outperform an aftermarket casting.

A cam only swap (with all supporting bolt-ons) can be an economical way to add just as much power as a heads alone upgrade contrary to the belief of those less motor savvy. You would just need to pick a more aggressive cam to make the same power increase as a heads alone upgrade would give you. There have been many tuners who have achieved in the neighborhood of 450 RWHP on an LS1 with full bolt-ons, big cam, and bone stock heads. There are also plenty of LT1 guys over on ls1tech that are putting down around 360-370 RWHP with stock heads, full boltons, and a cam only swap.

Another thing you should pay attention to is the advertised flow numbers from your head porter like N20LT4Bird pointed out. See if he can give you a graph so that when you are deciding on cams you can look at a specific flow number at a specific lift. I'm assuming you meant 258cfm @ .500" on the intake side. That is a fairly mild stage one port at best. It's just my opinion but if you are already going to have the heads off your car why not spend a few hundred more dollars and go for a stage II porting. You'll make about 20 more RWHP and it will widen the grin on your face.

It's just going to boil down to how much you have to spend. $700 is a very good deal for a mild port job. Tell him you will give him $900 for a stage II porting.

[Joe 1320]

A cam only swap (with all supporting bolt-ons) can be an economical way to add just as much power as a heads alone upgrade contrary to the belief of those less motor savvy. You would just need to pick a more aggressive cam to make the same power increase as a heads alone upgrade would give you. There have been many tuners who have achieved in the neighborhood of 450 RWHP on an LS1 with full bolt-ons, big cam, and bone stock heads. There are also plenty of guys over on ls1tech that are putting down around 360-370 RWHP with stock heads, full boltons, and a cam only swap.

LS1 heads are better than LT-1s so that's why they can get away with a cam swap on stock heads. Putting a CC306 or even a 305 with stock LT-1 heads will not give the desired results. It takes heads and cam to wake up an LT-1. Follow whatever advice you see fit, but it is a general slang term of us old racers that the car with the best heads typically wins. That phrase wasn't coined for no reason.

[darkz711]

Campbell, where did you get your LT4 heads ported or did the car come with ported heads. I like the AFR 195cc. Good price, around the same flow numbers as the heads i was going to buy but are professionally done with a CNC machine. I don't know who did the other ones and they are used.. plus the guy hasn't gotten back to me for a day now so he's probably going to lose my business.

Now that we are talking about heads... I have the three options, nice port on the LT1 stock castings, LT4 heads ( a little more expensive probably) or AFR 195cc ( most expensive). Which will i see the best performance from with a cc305 or LT4 HOT cam?

[N20LT4Bird]

Campbell, where did you get your LT4 heads ported or did the car come with ported heads. I like the AFR 195cc. Good price, around the same flow numbers as the heads i was going to buy but are professionally done with a CNC machine. I don't know who did the other ones and they are used.. plus the guy hasn't gotten back to me for a day now so he's probably going to lose my business.

Now that we are talking about heads... I have the three options, nice port on the LT1 stock castings, LT4 heads ( a little more expensive probably) or AFR 195cc ( most expensive). Which will i see the best performance from with a cc305 or LT4 HOT cam?

I bought the car with the heads I have, so sorry I cant help you there.

As far as the heads go, a nicely ported set of LT1 heads will out perform a stock set of LT4 heads. The heads you are looking at will not, so if its between the LT4's and those, go LT4 Also, keep in mind that a set of nicely ported LT4 heads, will outflow any LT1 heads - so theres a limit with the LT1's. I know that the AFR heads a real nice, but i have heard arguements that the LT4's are "the best". At least there are guys out there running LT4 heads on cars that would make my car look like a 92 HP civic.

As far as the cam goes, I really like my Hot Cam. It idles great, has real nice street manners and pulls like a freight train from 3500 to 6500 (and higher). It has been suggested to me to run the cc305 or cc306, but I did not try either, so cant speak from experience, but I have heard that both are good and you would probably get more power from the cc306.

It all depends on $$. You could get the LT4 kit, with the hotcam and roller rockers for 2k and make some nice power. Or if your tight on budget, the ported LT1 heads and a cc305 or 306 would make a good choice too. Or if you have lots of money, you could get a set of ported LT4 heads and the cc306 cam. You have to decide on your budget.

[Squat13]

The nice thing about the hot cam is that you dont need computer mods and you still get about 30 at the wheels. The CC 305 cam is going to need some computer tweaks and maybe some injectors , regulatior, and a degree wheel.