cheezer

Hey Guys,

I am in the process of getting the rest of my parts I need for my 389 stroker. The motor consists of:
0.030" over, decked 0.008", line honed and converted to a 4 bolt splayed main setup with Eagle main caps.
Cola 4340 forged steel crankshaft with a 3.800" stroke
Eagle Sir 'I' Beam 5140 forged steel 5.700" capscrew connecting rods.
SPEED PRO -18cc coated hypereutectic pistons
Clevite 77H Bearings
Hastings moly rings

My heads are stock castings fully ported Custom springs, Titanium retainers, comp locks, Ferrea stainless severe duty 2.00/1.56 valves. The flow numbers are:
.100……68/53
.200……147/115
.300……206/166
.400……251/196
.500……287/215
.550……296/221
.600……302/226

Right now in my garage I have a XE 224/230 cam and also the "306". I have been looking at the gm847 or a custom grind. What are your guys suggestions and also anyone have any ideas on the hp I will be looking at.
Thanks!

sssalah

Those flow numbers are awasome especially on the exhaust side, which suggests that a single pattern cam is good for this setup. Why the large 18 cc dish, are these intended for a boosted application?

SStrokerAce

Yeah I dont get that -18cc dish either. Those numbers seem a bit happy for a stock casting, 2.00" valve on a 4.0" bore...

FWIW those heads flow 12-16 cfm more from .200-.600 lift than the heads that I have seen work the best, flow doesn't mean everything but I do find most of those numbers hard to believe.

Bret

Deenasty

I too find those numbers way hard to believe especially with your size valves.

WS Sick

Believe me when I say go with a -12 cc dish instead of the -18.

I have the KB Hyper -18cc pistons and the compression is on the low side with a big cam.

I wouldnt run anything smaller than the GM 847 in that thing.

Deenasty

Im running -16, I would go -5

cheezer

The heads were ported by Carter Edwards of Edwards Motorsports. I am sure he'll chime in on this thread. Below is the info that he has listed from another forum.

I have been devising a port program for stroker motor LT1 cars and all out race 350 LT1's..The program I speak of is a break through in LT1 porting..I'm talking a 300cfm factory casting ported head!!These heads will outflow the AFR 227's and cost less....out of a factory LT1 casting!I have been working on this big port design for about the past 4 years..and once it's perfected I am having the runners mapped and a CNC program made for it to ensure a consist ant 300+cfm!When the program is completed this will be a revolutionary break through in LT1 cylinder heads, record breaking numbers and power with just a stock casting head.These will handle camshafts up to .650" lift as the base springs..but upgrades will be available for solid roller or the biggest of hydraulic roller cams.Each set will be hand finished to perfection after the CNC process, so your not getting just some ol' cnc heads.With the right camshaft these heads are capable of making over 450 rear wheel horsepower on a stock bottom end LT1!!!Final pricing has been set..but the program is not yet finalized..It is so close..as of right now I will give a sneak peak and say so far they are over 290cfm @ only .500"!!!! and at .600" they hit 298.8 cfm...I will post up when the numbers and CNC program is finalized..it is something I have been working on in my spare time over the past 4 years or so..and it's finally almost ready for production!! Just an FYI as well...I have seen certain company's claim to have a 280+cfm LT1 cylinder heads...but on the bench I use, those exact same cylinder heads wont even break 265. cough cough *AI* cough cough I think AI does great work no doubt...but With these new race port 300cfm heads I have coming..I will personally invite anyone who wants to come and watch the flow test performed for their heads or any others..this will be a true 295-310cfm LT1 cylinder head every time.Final flow numbers will be posted as well as pricing and full specs when the program is completed.
I want a post poll to see if I should produce this head in full force as well.Please post a reply if you have interest in this race port cylinder head, it is going to cost me bundles to get this operation rolling with the CNC process..but should be well worth it in the end to provide a new standard in the LT1 cylinder head development world.Thank's and let me know if you have any questions.

LOL it's no problem man, there are alot of skeptics out there because it's such an amazing deal to have a typical 23* runner hit 300cfm.Anyways to answer your questions:

198-200 cc depending on final volume and core shift.

SF-600 and SF-1020 I have used both and they are within 4-5 cfm of each other. and all at 28" h20

Bore size measured is on a 4.030" bore fixture..I have flowed them on a 4.125" bore too and they of course picked up..but i dont know why anyone would care about a 4.125" fixture if the LT1 blocks can only go 4.060"

I always use clay inlets.

Valve sizes are belive it or not only 2.00/1.56 I have only seen minimal gains by going with a 2.02/1.60 combo because the LT1 chamber is so shrouded due to it's size.

WS Sick

I think if you go with the -5s the cam choice and quality of tune will really play into that choice.

The -12s would put you around 10.6-7 (depending on heads and gasket) static compression, the -5s put you around 11.5 :1 static.

But with the right cam the 11.5:1 would be best for power.

WS Sick

Wow. I would like to see all that as well.

A local porter here in OKC cut , ported ,and welded an LT1 casting close to 290 something CFM. I may be wrong with the numbers but a guy here on the board has the heads on his 96 T/A (Nick 96T/A).

cheezer

SS MPSTR

Based on original post combo?

SStrokerAce

Well another head porter talking smack about someone else.... and claiming things that guys who have NHRA national records with these same castings and TONS more work in them don't do.... yeah... ok.

IF something is capable of making power then were is the dam dyno chart to go with it? If it hasn't made it yet, then it hasn't made it.

I've seen TONS of 300cfm 23 heads, it's not a uncommon sight. A 360cfm 23 head impresses me. There is just not the material in those castings to do 300cfm up top AND have fat low and mid lift numbers. When everything is 12+cfm higher than it normally is on heads from popular LT1 porters, to guys with national records and Pro Stock head porters and they are that much above in the whole range.... all that says to me is a happy bench.

As I have said. I'll believe it when they send me a head with one port in it that flows that amount. Any head porter worth his salt would do that since if he can do this has mulitple sets of these heads laying around and one intake port in one head isin't going to take that much to do and ship out.

Sorry if I'm such a synic, but I have to see the dyno and the flow bench to believe it.

Look up airflowdevelopment (Dennis) comments on the same 300cfm LT1 head thread....

Bret

94Z396_0621

Can you not run any bigger valves than a 2.02, 1.60 in a stock LT1 head? I went the Trick Flow route and Loyd Elliot and they turned out awesome. Very well ported.

SS MPSTR

We racing flow numbers again?

SStrokerAce

You can if you replace the seats in the heads.... 2.055" valves are fine with new seats.

Bret