LS1 Head Castings

**David Ray** · 05-24-2009, 08:52 AM

I've got the LS6 intake on my '01 Z28, but the heads are #241 castings. Some say that that is a later casting just prior to the LS6 heads. I also heard that it flows better than earlier castings. Does anybody know how it compares to the LS6 heads. Are they so far off that I would need to upgrade when I decide to install the '02 LS2/6 cam?

**ls1camino** · 05-24-2009, 11:51 AM

Originally Posted by David Ray

I've got the LS6 intake on my '01 Z28, but the heads are #241 castings. Some say that that is a later casting just prior to the LS6 heads. I also heard that it flows better than earlier castings. Does anybody know how it compares to the LS6 heads. Are they so far off that I would need to upgrade when I decide to install the '02 LS2/6 cam?

1. F-Bodies NEVER came with LS6 Heads. All 2001-02 F-Bodies came with the LS6 intake and I think about 10% of 2002 F-bodies came with the LS6 Block.

2. 241 Casting are the LS1 Heads for the 2001-02 F-Bodies. The 1998-2000 had the 853 Casting Heads.

3. Someone else will have to chime in on the flow numbers between the LS1 and LS6 Heads.

4. Don't put a LS6 cam in your car, get at least a 224R or 228R cam. You will see almost no gain with a LS6 cam. If you're looking for driveability, the 224R and 228R cams are both easy to drive on the street.

**c5z28** · 05-24-2009, 11:55 AM

Far off? What exactly are you looking for again?

**TACE02** · 05-24-2009, 12:11 PM

http://www.smokemup.com/tech/ls1.php

here is what I was able to find. Not sure how accurate it is for the cams, but the heads sound about right (853s and 241s considered LS1 heads, flowing the same). The LS6 heads do flow a little better, but if you are worried about flow, go P&P aftermarket, stock LS6 aren't worth spending money on unless they are P&P. I coulda swore the 98 had a different cam then the 99-00, but I could be mistaken. As for you installing a cam, why would you want to go through all the trouble to pick up a few ponies and a little bit of torque??? You would gain more from LTs or a tune. Not saying go big, but there are plenty of driver friendly cams out there that will plant your ass firmly to the seat at WOT.

**TransAmFanatic** · 05-24-2009, 02:12 PM

hmm thanks i was looking for a cam with dirvability on the street.

**David Ray** · 05-25-2009, 03:04 PM

Are you saying I won't pick up any HP with a cam upgrade. I thought it was one of the best ways to pick up the pace. I'm pretty sure I'll have to take the heads off this year (bad lifter?) and thought I would upgrade some things while I'm there. This is what I currently have:
LS6 intake;
SLP cold air intake with K&N filter;
long-tube headers with cats (can't make out what brand, but they look fairly new);
MSD plug wires;
cat back exhaust with dual tips.
I'm not sure if my car has been tuned before, I'm still in the process of changing all my fluids and plugs, etc. I've only had the car a few months. What about the rockers and springs. Can any increases be had there?

**TACE02** · 05-25-2009, 03:19 PM

You will pick up HP/TQ with a cam upgrade, thought you were talking about putting a stock LS2/6 cam in... would only suggest if you are gonna put a different cam in, go with at least a 224 or bigger, to see some real HP/TQ difference.

**ls1camino** · 05-25-2009, 03:27 PM

Originally Posted by David Ray

Are you saying I won't pick up any HP with a cam upgrade. I thought it was one of the best ways to pick up the pace. I'm pretty sure I'll have to take the heads off this year (bad lifter?) and thought I would upgrade some things while I'm there. This is what I currently have:
LS6 intake;
SLP cold air intake with K&N filter;
long-tube headers with cats (can't make out what brand, but they look fairly new);
MSD plug wires;
cat back exhaust with dual tips.
I'm not sure if my car has been tuned before, I'm still in the process of changing all my fluids and plugs, etc. I've only had the car a few months. What about the rockers and springs. Can any increases be had there?

Originally Posted by TACE02

You will pick up HP/TQ with a cam upgrade, thought you were talking about putting a stock LS2/6 cam in... would only suggest if you are gonna put a different cam in, go with at least a 224 or bigger, to see some real HP/TQ difference.

I didn't say you wouldn't pick up anything from a cam swap, I was saying that the gain from a LS6 cam is almost nothing compared to stock and that you sohuld go with a bigger cam, like a 224R or 228R (both good DD cams).

**Spaz** · 05-25-2009, 03:44 PM

LS6 heads are 243 casting...

this is from my car that i have swaped a LS6 in to a few years ago...

**David Ray** · 05-25-2009, 04:01 PM

What's a DD cam?

**TACE02** · 05-25-2009, 04:19 PM

Daily Driver, a cam that has a close to stock feel, yet netting you a considerable more amount of power over a stock cam. DD as in not causing the car to jump or jerk at low RPMs while driving in the city.

**getcha01** · 05-25-2009, 04:59 PM

Originally Posted by David Ray

I've got the LS6 intake on my '01 Z28, but the heads are #241 castings. Some say that that is a later casting just prior to the LS6 heads. I also heard that it flows better than earlier castings. Does anybody know how it compares to the LS6 heads. Are they so far off that I would need to upgrade when I decide to install the '02 LS2/6 cam?

I have actually heard never seen on paper that the 241 heads made about 10hp more than the earlier heads, and the LS6 heads made 15hp more over the 241's due to smoother angles,larger ports, and makes your engine have 10.5:1 compression over the stock 10:1....but I really wouldnt mess with LS6 heads or cam, because a 2001-2002 LS1 they all had 241 heads and the dyno shop that I talked to here in southern illinois told me a 2001 SS he tested was rated at 325hp and the 01 and 02 LS1's made usually around 295-310 RWHP even on Z28's that were rated at 310hp, and he's seen WS6 and SS pull 300-335RWHP...all stock, and he said the Z06's that were rated at 385hp would pull around 320-340RWHP....he thinks the heads and cam on the Z06 only made a couple more hp over the LS1 and that he thinks its all in the exhaust...he said a 385hp Z06 that had headers installed would make 15hp max cause the exhaust manifolds are made better on the LS6 engine, but he said the LS1 cars he seen with headers would make up to 35hp more just from stock manifolds to LT headers...so personally I think LS6 heads n cam would only give you about 10 or 15 more hp...but headers and 228 cam, and some head work on the 241's youd be changing your rear end soon after all that.

**David Ray** · 05-25-2009, 07:26 PM

I BET I WOULD TOO! I got the headers, but I need the cam. So, a 228 cam would boost the hp and still be good for driving around town? Do I need to change the pushrods and springs too? Can you tell if the valve lifters are stuck when you take off the valve covers? I've got a tapping noise that sounds like a lifter, but I'm not fer sure. Is there anyway to tell without pulling the heads. I believe I would be just as happy with a cam/spring /pushrod/rocker upgrade...maybe a new timing chain and SLP oil pump. Aw hell, I want it all! Anyway, if I could get away with keeping the stock heads and just upgrading the valvetrain then get a good tune, with the cold air intake and headers I bet I would be in the upper 340's or more.

**c5z28** · 05-25-2009, 07:42 PM

Originally Posted by David Ray

I BET I WOULD TOO! I got the headers, but I need the cam. So, a 228 cam would boost the hp and still be good for driving around town? Do I need to change the pushrods and springs too? Can you tell if the valve lifters are stuck when you take off the valve covers? I've got a tapping noise that sounds like a lifter, but I'm not fer sure. Is there anyway to tell without pulling the heads. I believe I would be just as happy with a cam/spring /pushrod/rocker upgrade...maybe a new timing chain and SLP oil pump. Aw hell, I want it all! Anyway, if I could get away with keeping the stock heads and just upgrading the valvetrain then get a good tune, with the cold air intake and headers I bet I would be in the upper 340's or more.

If you have an m6 with bolt-ons expect 350ish rwhp.Our cars are noisy if the noise you speak of goes away when it warms up that is normal. If you do a cam swap you will need to buy hardened pushrods and valvesprings, and an oil pump is not a bad idea. I would start cam shopping to see what you like, there are alot of cams out there.

**David Ray** · 05-25-2009, 08:37 PM

I do have the m6...makes me proud! The noise goes away, or at least gets real quiet after she warms up, but I'm not much of a mechanic so I don't know what it is. I listened to a vid that Sarge posted that was piston slap and it sounds alot like that, but it rattles after I let of the accelerator - sometimes badly. I'm going to have to check it out. Can you push on the push rods or rockers to diagnose a bad lifter?

**c5z28** · 05-25-2009, 08:40 PM

You may post a vid of the noise to see if anyone can diagnose the problem.

**David Ray** · 05-25-2009, 08:55 PM

I'm gonna try tomorrow to video/post and see what's up. Thanks for the info.

**TACE02** · 05-27-2009, 09:59 PM

Originally Posted by David Ray

I do have the m6...makes me proud! The noise goes away, or at least gets real quiet after she warms up, but I'm not much of a mechanic so I don't know what it is. I listened to a vid that Sarge posted that was piston slap and it sounds alot like that, but it rattles after I let of the accelerator - sometimes badly. I'm going to have to check it out. Can you push on the push rods or rockers to diagnose a bad lifter?

are you sure the rattle sound you are hearing is coming from the motor... could be just a heat shield... I know mine rattled like a son of a ##### (especially when I let off the gas), I just simply removed all heat shields, no more rattle. Or an exhaust leak, missing or loose header bolt. Either of these two can make you swear something is wrong in your engine, would check these two first.

**5abivt** · 05-27-2009, 10:07 PM

I have a noise that only happens on cold startup and goes away in about 45 seconds. Piston slap. I learned alot about this with the vettes on the forum and it is very common. i picked up my z 2 weeks ago and sure enough it had it too. I don't touch the throttle for about 40 seconds and then shes good to go.

**getcha01** · 05-31-2009, 06:46 PM

Originally Posted by David Ray

I do have the m6...makes me proud! The noise goes away, or at least gets real quiet after she warms up, but I'm not much of a mechanic so I don't know what it is. I listened to a vid that Sarge posted that was piston slap and it sounds alot like that, but it rattles after I let of the accelerator - sometimes badly. I'm going to have to check it out. Can you push on the push rods or rockers to diagnose a bad lifter?

Im a little late on this because I usually just get on here couple times a week unless im on a roll...but he's right, theres a lot of cams out there, dont go with Z06 cam for sure, cause it aint much, just race a Z06 vette around your year car and you will see why I say that...they arent much faster if any at all..they handle great, way better than a WS6 and the WS6 handles awesome over my buddys 98' Z28....you do need hardened pushrods and bigger valve springs, an while your at it have your machine shop do a valve and port matching job to them to help that new cam out...the stock heads are aluminum, and back in the day that was the big thing, so you can really work wonder out of our F-body heads, but the block is a little thin in the cylinder walls to get too crazy lol, after all that make sure to get it dyno tuned and have every head,valve,cam,bolton spec to give to the tuner so he can get it perfect, I seen my buddys 98'Z28 go from running 13.90's with headers, then every boltons,intake,gears and all but cam and internal parts, he got down to 13.30 with 4.10's, and a 3,000 stall with nitto's, and I outran him in my 01' WS6 at the track the 2nd week I had my car, I ran 13.08 with just a SLP lid,msd plug wires, and a tore up tranny....then I had about $6,000 done in my tranny,clutch,headers,other boltons, and havnt ran it yet, and he had just a dyno tune done and went 12.47...he dropped .8 tenths of a second from a tune, they said everything he had done was starting to slow it down actually and mess computer up...mainly with the cat delete,New intake and the LT headers, its was putting wrong gas mixtures in and what not....I installed LT's, and deleted my cats, and had a $3,000 bench tranny job done, and installed my spec clutch, then got laid off, and now my clutch is out after 3 months of having it in, my tranny guy said water got on it, bit Im sending it to spec and we will see...then im going to beat my buddy's 12.47 cause he usually cant get me on the street........smileeeeeeeeeeeee