JKD

How important are the .200 numbers when comparing heads? Or , should I focus more on the .3-.550 numbers? Also given the 2 specs, which head looks better?
Runner. INT. EX.
235cc. 2.1 1.6
225cc 2.055. 1.575

Jimbo1367

Remember when comparing flow numbers that different co.s May use different bore diameter and that will skew trhe results. Also some use exhaust pipe. I am weary on flow numbers unless they are all flowed on the same bench

JKD

That's my concern. These are from 2 reputable company's but are they apples to apples. The smaller runners look much better from the data that is displayed, but is that really the whole story? Ah grasshopper, there is much to learn.

bortous

Either head will be very similar.
Still prefer the mamo route though.

JKD

I still favor Mamo's stuff, also. Just looking at the data as presented however, the small runner, small valve head that is out performing the larger head is most appealing for a street machine. The I/E ratio is outstanding as well.

Darth_V8r

iTrader: (4)

I actually do not put too much stock in exhaust flow numbers. There is a piston pushing the gases out. This is why when bore gets bigger, you see the exhaust valves really don't grow much, but the intake valves do. Getting air out is more of a certainty than getting it in. More likely to have problems from a poor exhaust system than the port itself.

JKD

I have experienced that. 3" y-pipe is not considered a good back half to an exhaust BTW. Lol. We are still seeing comparable flow numbers from a 10cc smaller runner and a .050 smaller valve. I believe we are probably splitting hairs on a motor that will never take full advantage of the minute details being pointed out here. It probably comes down to a H/C package that works together. They are close when looking at budget.

Darth_V8r

iTrader: (4)

Yep. I think at this point you are splitting hairs going back and forth between them. I think you'll find that both heads with a mid 220's type cam will do fantastic in your 416.

bortous

Just get the mamo setup and be done with it man.
You will be glad you did.

JKD

I know. Its just my nature to look for the hidden advantage. I raced jet skis for years and it is a sickness we all share. Looks like I'll be calling Tony soon. Lol.

JimMueller

iTrader: (9)

I like this video from Richard Holdener. He compares 11 different heads (10 cathedral and 1 rectangular) on the same flow bench and provides practically all of the normal measurements, but he doesn't state the bore and exhaust pipe. Based upon the curtain area coefficient of discharge of the cathedral heads, the Texas Speed 237 had the best overall CoD, followed by the TEA 243.However, the TEA 225 and MMS23 were not included in these results.


If price wasn't a consideration, I'd certainly opt for the MMS heads to feel confident I wasn't leaving anything on the table. If you're concerned about how much you are gaining for your money over the non-MMS heads, that is subjective.

JKD

Honestly, I will probably never touch the full potential of any of the heads we have discussed. This is a street machine and a frequent driver at that, once it lands in the panel truck. I build them to drive. I have approximately 100k miles on the 210 heads and they show no I'll effects. Could they be gone through and freshened up? Of course. But they have served me well and the quality and support I have received goes a long way to influence the decisions I make. I will use the MMS235's. Block and goodies are going to the machine shop next week. I will update as things progress. I appreciate everyone's opinions and help. Thanks.

Jimbo1367

makes sense

JKD

Picking up the block from the machine shop tomorrow. Wound up having to replace a sleeve on number 7. it had a crack in it. Wish I new that before I purchased the Pistons. I would have certainly gone larger bore than 4.07. Anyway, block is fully prepped for 4" stroke, line honed with ARP studs on mains and studs for the heads. Now, should I get OEM covers or ??? When I bought the block it was bare. Only main caps. I need the cam retainer, timing cover, rear cover, and valve covers. Anyone have any experience with the 2 piece timing, Good or bad? I will be going with the VVT camshaft.
Recap of parts so far:
Mamo spec'd
Manley 4" stroke
Manley 6.125" rods
Wiseco 4.07" 15cc dish pistons & rings (10.5:1 with 70cc chambered heads)
King bearing
Still researching heads (leaning MMS235)
Already have the:
LSXR 102 Mamo ported
102 NW TB Mamo ported
Have a cam spec from Cam Motion (224/230 588/575 114+4 3bolt
Still researching VVT as I want to utilize this from the L99
Anyone feel free to add a cam spec, especially if you have VVT recommendations.
Engine **** forth coming once I get it on the stand.

bortous

242/246 114lsa+ 3

Darth_V8r

iTrader: (4)

For a lighter car or something high revving, that's not a bad option at all. OP is putting this into a 5K+ lb tahoe and wants strong low end grunt. That's the reason for the smalle port heads and the smaller cam. More of a stump puller than a barn burner...

JKD

Thanks Bort, but Darth is right. I am looking more under the curve . I really want to use the VVT, but finding someone that has the data for the goals I have in mind and experience with VVT is proving to be a challenge. I may just stick a LSA or Whipple on the thing and call it a day. Hell I could use some stock ls3 heads at that point and use the savings for the blower.

old motorhead

iTrader: (10)

Stock LS3 long block + Heartbeat TVS2300 + mild blower cam + bolt ons equaled 660+ rwhp at a mild 9.5psi on my last supercharged ride. I think it was over 500ft/lbs from 1500 through 5500rpm. Torque peak was 610+. Something like that would make that fat girl feel a few thousand pounds lighter. A 220/232 116 would be plenty of camshaft and would drive a little better than what you're considering now.

bortous

226/230 115lsa +3

JKD

This is the type of power I am looking for. I believe I will crunch the numbers and see where it falls.