raymondvp45

After alot of research on this forum i decided to roll the dice and port one of my 243 castings. I removed the rocker arm "hump", re-shaped the valve guide shroud, blended the bowl, did not remove the swirl ramp ,and just removed the cast flash on the short side. The runner is 215 cc's now with stock size valves. The port looks extremely smooth (sorry no pictures my camera is broken). The temp. was 61 degrees in the shop. The heads were flowed on a "flow pro" at 28". here are the #'s

stock 243 home ported 243
.100 63.0 62.7
.150 98.8 99.1
.200 134.6 135.4
.250 163.0 165.4
.300 191.4 195.3
.350 212.2 218.9
.400 232.9 242.4
.450 246.7 258.5
.500 260.5 274.6
.550 253.9 266.3
.600 247.3 257.9
As you can see the low lift numbers were about the same. The ported started taking off at .350. Both heads stalled at the same lift point. I wasn't too pissed cause both heads did it at the same time. The stock one was howling like a monster tho. Could it be a possibility that the temp.(62. degrees) air density could have caused them to become turbulant early? i don't know. This is the first time i put a grnder on a head so 'm happy with the results, better than the 241's i have on my car now. When i'm done with the other head im throwing in a 224/224 .563112 from tr. Hopefully the cam will respond good with these heads.

hotrodrx7

iTrader: (13)

Not to shabby. Have any before and after pics?

Mikey 97Z M6

iTrader: (37)

Not a bad pickup for the minimal amount of port work. I've had good luck porting LT1 heads in the past, so I'm gonna try my hand at my first set of LSX heads in early December when I tackle some 5.3's. They're getting the works thrown at them though and, hoping for somewhere around 290+.

Did you run the bench yourself or someone else?

Mike

raymondvp45

Someone else flowed them for me. I did'nt want to get crazy with the grinder, my goal was to gain flow and keep port velocity. I'm still curious about the drop. If the ported one was the only one that dropped than i can blame a bad port job but the stock one did it too, and as i mentioned before you can really hear the tumble on the stock one. i'm gonna try and get some pics.

Mikey 97Z M6

iTrader: (37)

Have you tackled the exhaust side yet? I always had more trouble with the exhaust side for some reason. Not sure if it's because the flow is reversed or what, but from my previous porting experience, the exhaust numbers didn't seem to on par with my intake numbers lol... In the end I had to get a backcut on the valve to get the numbers I wanted.

Mike

raymondvp45

here are a couple pics, sorry they suck they came from a camera phone.https://ls1tech.com/forums/attachmen...id=79950&stc=1
https://ls1tech.com/forums/attachmen...id=79951&stc=1[url]https://ls1tech.com/forums/attachment.php?attachmentid=79953&stc=1https://ls1tech.com/forums/attachment.php?attachmentid=79955&stc=1

slimcracka

iTrader: (7)

looks good man keep up the good work

66deuce

iTrader: (1)

stock valve job?if so,you could pick up more by having one of the more experienced shops do one plus a backcut on the valve...

GuitsBoy

iTrader: (4)

not bad man! Nice to see some tangible results from a DIY port job. That exhaust port looks bling-blingin.

raymondvp45

Any theories on why both heads flow started to drop after .500?

GuitsBoy

iTrader: (4)

Though its not an expert opinion, it may simply have to do with not opening up the runner up much. And that you didnt take the swirl ramp down. IMO the cross section more or less dictates the top end flow. Keeping the runners small and the swirl rams should bolster your low end though.

Studytime

iTrader: (15)

You experienced flow seperation off the bottom of the port. My first set did this too. This is when it's judgement time. If you're happy with them and not running high lift, then make all the rest of the ports match your 1st. If you want to improve high lift flow, it's time to sit by a flow bench and start working on the short side radii.

Might consider just putting them on the car if this is your 1st set. I'm glad I could share the above info with you. I didn't have anyone to share it with me, so hope it helps. :diegrinding:

Ben T.

raymondvp45

Thanks, i appreciatte the help. i might just leave them like that. My cam has a .563 lift, wich it will suffer a little past .500 where it is becoming turbulant. If my cam was a .580+ lift then i would have messed with it some more. I was just gonna install the stock 243"s in the car but i'm glad i improved them a little. my goal is 400 rwhp with the tr 224/224 .563 112. anything more than that is gravy to me. i hope i can achieve this!