it suppose to be? I did install a rt45 (stock L48) plug in them at home and it looked to be too short.
I didn't have a .75 reach plug to try. I do not know what plug is recommended for these heads.

 

I've seen plugs that didn't make it into the chamber, killing the ignition source. jus trying to be helpful .

 

I will look in to the spark plug reach thank you for the tip.
Any other tips while I have the heads in the machine shop?

 

Update!!
After reviewing these heads with Steve sanchez at total flow products I have decided to not go forward with these castings do to a few issues with the raw casting.
A set of dart castings will be delivered today to keep this project moving.

 

What kind of issues? Sounds serious.
You going with Dart SHP's?

 

Issues with these heads.
Installed on a 4.00 bore 350 to scribe the bore on the cylinder head deck and found the chamber diameter is larger than the cylinder bore.

The bowl is too way large for the valve seat ID. And the intake runner size.

Intake to exhaust valve spacing to close to install a larger intake valve to help with the very large bowl area.

Intake openings too tall to match with a standard port intake manifold (iis performer 2101)

Steve did say the pinch point looks nice. His over all opinion is any head would be a better choice for my application.
The advise I was given is to get a set of dart shp 180's unassembled and he will blend the bowls, clean up the ports, match the chambers to the bore and deck to acheive a 60cc chamber

 

If he gets SHP's that were as off on chamber size as mine the smallest chamber size he'll be able to achieve is 61cc's. I shaved mine down .030" leaving only .007" before intake valve interference and could only get 61cc's.
My chambers were advertised at 64cc's and were around 67cc's out of the box.
You may also find that the intake runner is more than 180cc's. Mine were as big as 198.6cc's before porting.
Definitely a good idea to clean up and blend before install, I found plenty of work to do there.

 

SHP's were delivered today..your information about chamber and port sizes is exactly what Steve says about dart heads. The direction i am going to to mill as close to 60cc as we can then make a decision to angle mill if they do not fall in to 60-62cc range.

Another issue with the formerly mentioned heads is the valve seats have a step under them since the throat is so large.

 

Get him to port match the intake to heads and flow them with and without the intake attached. No point in doing any work on the heads to gain 4cfm and lose 10% cfm or more overall because the intake doesn't line up with the heads

 

Was the .007" the intake valve to cylinder bore interference?

 

I will have him do that.
With the the first mentioned heads I doubt the intake would be able to seal since the ports are so tall and the performer doesn't have that much material at the top of the intake port.

 

That was the material remaining on the head surface that could still be removed before the mill hit the intake valve.

 

Wow ace, your becoming the expert on aftermarket heads for the sbc. I enjoy the reading here and thx for posting as it does help others. Somewhat scary reading how good looking heads with desirable specs are of such lousy quality. Brand names like GMPP, World Products, RHS, Edelbrock, AFR, Trickflow now speak for themselves. One new budget mfr that is getting good reports is EQ (engine quest) used by IMCA small racing circuits. EQs are sold mostly on ebay - u may want to take a look (cheap) or try: TOLL FREE 800.426.8771. https://www.starperf.com/iron/engine...cylinder-head/

EQ CYLINDER HEADS: FLOW NUMBERS

EQ strictly by the numbers. How our heads stack up.

Need to know how our numbers compare against the competition? EQ provides you with the following extensive list of cylinder head flow numbers to help you decide.

CH350C
Chevrolet V8 5.7L Vortec
Intake
Lift CFM
0.1 54
0.2 103.9
0.3 147.6
0.4 194.4
0.5 224.3
0.6 226.2
0.7 228.4
Exhaust - Without pipe
Lift CFM
0.1 49.3
0.2 87.6
0.3 118.8
0.4 139.7
0.5 148.5
0.6 152
0.7 152.7

CC180BA
180 cc intake runner / 64 cc combustion chamber
Intake
Lift CFM
0.1 65.4
0.2 130
0.3 177.9
0.4 212.8
0.5 234.9
0.6 242.3
0.7 244.3
Exhaust - Without pipe

Lift CFM
0.1 55.3
0.2 106.6
0.3 133.2
0.4 156.6
0.5 174.5
0.6 182.8
0.7 188.3

The L48 is a bit difficult to improve due to the lousy stock pistons. Even with a thin steel shim head gasket the piston remains 0.025" down the hole which reduces quench effectiveness.
My thinking is vortec heads are the best head the L48 deserves and my WP torquer IIs are nearly overkill.
But it reads like u are shopping for heads that can be used in future builds so good luck to u. But dont be surprised if those SHP heads dont realize their potential until used on a better block/bottom end.

Good luck and post your results,
cardo0

 

The only two people I have seen buy these have sent them back with issues. Pretty sad.

 

Here's what a top shelf head looks like. I am a big fan of AFR heads as I had mine checked for everything including flow numbers, CC numbers etc and they were right on the money as advertised




Ferrea Valves bought separately

 

Unfortunately I am past the return point since I purchased the heads a few months ago. They were inexpensive so the will become wall art in my garage ...lesson learned

 

ace, thanks for posting, I was going to buy heads from straub but after reading this I am going to rethink and probably going to go with Dart, maybe look at edelbrock...

 

Chinese junk, they are experts at copying things, they look not too bad but don't work, my last experience was buying a Chinese lighter. The only thing this device was supposed to do was produce a flame, it didn't even do that.

 

I agree with you 100% on using name brand quality parts. To help insure there are no other setbacks I chose a local cylinder head shop with a well know reputation and a know good brand of heads which are local to me as well.
Had I listened more closely to the members here I would of saved a few $$ and been farther along in my project than I am. There is no benefit in $$ time or performance trying to use a low quality part.

I will keep this updated as it comes together. I can't say enough about total flow and Steve Sanchez great guy to work with.

The top end will be
Q jet
Performer 2101
Dart shp 180's milled decks to bring compression to 9.2-9.5
Comp cams xr276 12-423-8
Bottom end stock Goodwrench 350.

 

Buy the AFR heads and don't look back.