Infamous

Getting real close to droppin' the hammer on some parts here. Been looking at the TSP/PRC 5.3's and LS6's that are CNC ported. I put a call into ET Performance and spoke with them about what options are available to me. I told him I was looking for around 400-415 rwhp for a street car (this is a '68 Camaro Pro-Touring car). 4l60E, 2800-3200 stall, 3.73 gears, 26 inch tall tires. He shot down my 228R cam and suggested one from Comp, a 224/226-114 and then said he could rebuild my 853 castings and port them to easily make that much power. He says he's had applications with ported 853's that have been close to 500 at the motor with the cam he was talking about. These guys seem pretty reputable, and they're in Michigan which is a bonus because I'm big on supporting our economy here. $1000 for the heads, $400 for the camshaft. That fits my budget. What do you guys think? Do those numbers look achievable with those components?

GuitsBoy

iTrader: (4)

Sure, differences between ported 853 and ported 241 are nill. And the difference between those and ported 243 are pretty small too.

Infamous

Well if the stock castings are so good...why all the noise over 5.3/LS6 or aftermarket heads? Are those for punched out applications (383) or ones with power assist (turbo, supercharger, NOS)? Just trying to gain some understanding is all, still new to this.

GuitsBoy

iTrader: (4)

both of those offer higher compression. Stock the 5.3 has a smaller 1.89 int valve, so really its only a good choice if its been worked over. The LS2/LS6 or 243 castings have higher compression as well as better flowing ports. The untouched head will make 10 - 15 HP over a stock LS1 head.

Once all these castings are ported, theres only a handful of HP difference between any of em. The real step up is in the aftermarket castings after that point.

Billdog350

iTrader: (3)

If you're spending $1000 to port your heads, why not spend the same amount for NEW 243 (LS6) castings that have been already ported? I know I bought my Texas Speed (PRC) ported 243's for around $1000. Remember you'll need new valvesprings with a new cam too, regardless of which heads you choose.

Infamous

Well, to update the springs on those heads and after you add on shipping the TSP heads end up being an extra $180 (for a head that apparantly won't be much better). ET Performance wants $1030 to rebuild and port my heads and they'll already have the stronger springs in them. Plus no shipping costs, Walled Lake is about 20 minutes from where I work. $180 might not seem like much to some but when you're on a tight budget, it's a boatload of money. Thanks for the suggestion though. I have bought parts from TSP before (ported LS6 oil pump, LS2 timing chain) and will use them again for some of the remaining components I need (gaskets, hardened pushrods, thermostat). Good people over there.

52172

iTrader: (2)

I put down 415/403 with my ported 853 with short tube headers and a small 222/224 comp cam and an ls6 intake unported.

Infamous

Awesome, that'll be enough power for this car.

For now anyway.

KCS

iTrader: (20)

Yeah, I agree. Ported 853's should be enough to support the power you're looking for. Good luck!!

52172

iTrader: (2)

Yea especially if ETP ports them. You won't need a new head unless you go larger bore or FI over 800 rwhp.

MPHmotorsports

iTrader: (18)

I am a ET dealer and will say their work is top notch.
Honestly you could hit your goals with any of the better more repd companies out there. Even a stock 243 casting head would get you in that range in a M6 car.
I would go a hair bigger on the cam myself and bring the LSA down. We have done a few 228/232 59x 59x 112+2 combos lately have have been great performers.
ET however will guide you in the right direction and if they don't then you live close and could always kick Craig in the nuts. He only uses those at the gay bars anyways.
LOL

Infamous

LOL!!! Thanks guys, I appreciate all the advice.

Asmodeus

I originally wanted to do ported 853's, a cheater cam, ported exhaust manifolds, gutted cats, lid, a quiet catback, a built forged shortblock (coated everthing, etc, gas ported pistons, etc), stall, and a 200 shot... then street race it for money...

Craig@ETPerformance

iTrader: (1)

Stop on in and see us. What your horsepower goals are we can do for and help you along the way. The ported 5.3 heads or even a set of standard 5.7 castings will get you there as well.

MPH, only when I am following you in.

MPHmotorsports

iTrader: (18)

LOL. You always like to be behind guys.
You get some LS7 heads yet?

WS6TransAm01

iTrader: (13)

no offence but you are on crack...

There is a HUGE difference in HP on ported 853's 241's and 243's

I am making 508rwhp with ported 243's on a stock bottom end H/C car. Show me one car making similar power with 241's? There are few cars making that power with aftermarket heads, let alone 853's 241's or 5.3ltr heads.

Infamous, if you have a 346, I have never seen a car made almost 500rw with 853 heads and a 224/226 cam. If you have more cubes then that is different. In my oppinion, 243 heads are failry inexpencive for cores, I would get them ported well and you will be very very happy!

Other heads just dont make sence unless you are looking to do it cheap, then you can use 241's 5.3's or 853's or if you have a lot of money you can use TFS or the like.

GuitsBoy

iTrader: (4)

Differences between 853 and 241 castings comes down to one thing. The mold. 853's used sand cast, while 241's use a semi permanent mold. The ports and runners are identical. The SPM is a smoother, more consistant finish making a slightly higher average HP than the sand cast heads. Once ported, this no longer matters since the endmill, burr or cartridge roll produces the finish. How exactly will one chunk of metal produce more power after theyve been ported???

There are some differences between 241's and 243's. The D shaped exhaust port, and the larger intake runner. Stock for stock castings, the ports only yield in the neighborhood of 10 HP (once you eliminate the gains from the LS6's higher compression). Porting runs the gamut from mild to wild on both the 241 and 243 castings. You can have a crazy port on a set of 241s that will make more power than a mild port on 243s, an of course vice versa. There are exotic porting programs for any of the LSx castings that make great power. What do you think they did before LS6 heads were available in 2001??? MTI, LPE, Cartek, etc. all made some great numbers on good old LS1 castings, but with the cheap price and availability of LS6 castings, it makes sense to use them now. I still stand by my original statement that assuming comparable porting programs, the 243's will not be worth much more than 241 castings.

You should really make sure you know what you're talking about before you go around telling others that theyre on crack...

52172

iTrader: (2)

I guess you call huge 10-15 cfm of airflow???? Any excellent head porter can get an 853 flowing 330 cfm on the intake and take that same porter and give them a 243 casting and the flow only goes to 340 cfm

Studytime

iTrader: (15)

There's more to it than flow numbers.

You have to consider flow quality improvements. The LS6 head has a much improved short side radius and more window area at that cross section. Porting a LS1 head can't put material back into it to make a taller short side radius. Also, compression helps the LS6 heads from the smaller (cast) chambers and they have a better designed chamber. There are numerous advantages that LS6 heads have over LS1s. Some of them (the shape of the roof for example) can be replicated to LS1 heads, but others can't.

All in all, there wouldn't be a huge power difference, but I'm sure there is a slight power difference in favor of the LS6 heads as well as torque advantage.

With all of this said, I'm doing 241s on my personal car. I know I won't hit 500rwhp, but it really doesn't matter. Most people don't use all of the power they make anyway (poor suspension, too little traction, 10-bolt, etc.).

For the average 99% street car, 1% track car either ported GM casting would be just fine.

Ben T.

purdueranger

iTrader: (11)

I put down 408/380 with untouched 853s.