I have the trickflow 305 cylinder heads and was curious as to how much flow you guys think could be made after cnc porting? They look to have plenty of room

 

So far, noone has told of porting those, let alone flow numbers afterward. Just lightly polish the exhaust ports, and try them. If you want a nice safe stage 1 port job, I'll do it free if you pay shipping both ways, but if so, I own rights to any and all photos I take. I'll post them in my "how to port SBC heads" sticky thread in the Engine Swap sub-forum.

 

Hard to turn that down. Reason I ask is be ause they
have to come off for some repair work due to a know it all friend that stripped a hole for
the intake and cross threaded a spark plug in the same head. Blamed both on the torque wrench but threw down 50 bucks and offered to buy the
gaskets... Where do you live?

 

If they are modeled after a L98 type head, but are at 175cc to start and around 240-250cfm to start I dont see why you couldnt hit 275 cfm while keeping volume under 185-190cc just like the AFR 180's. thats just a guess. They can do 260 on a 113 L98 head and theres not as much material there to port.

 

PM sent. As to what ORR typed, the flow is gonna be limited by the valve size, which is limited by the bore size. With a stage 1 for a 305, that means keeping the 1.94" intake, so most of the gains will be in the mid-lift.
If the heads get cut for 1.60" exhaust valves before being shipped to a porter, then flow should improve markedly in the mid and high lift areas. If 1.50" valves are kept, then most of the improvement will be at higher lifts.

 

OP - Are these heads on a 305 or 350? How do they run out of the box?

 

Yeah on the smaller bore I'd expect to see less flow. You can get good flow out of a 1.94" valve. I may be overestimating these heads however 260 cfm would be very nice out of these on a 305 bore

 

Orr, did you ever read all of those neat little booklets that arrive with it when you order a brand new SuperFlow 1020 with every option? I did. And one of the things you learn, and which my own extensive testing verified, is that you just can't get more than 245 cfm past a 1.94" valve. This may not hold true in Tony Mamo-ported LM7 heads, but for Vortec 350 heads and such, it is gospel, inviolable, et cetera.
Of course, adding boost changes that, but we weren't discussing power adders.

 

really, I thought for sure I've seen numbers posted for over that figure on a 1.94 valve. I think i was quoted 250's cfm out of 1.94 valve L98 113's before from a reputable porter. What port velocity is that 245 at?

I was reading on vortec heads that some guys have seen anywhere from 230's to 250 cfm out of a stock casting but the 250cfm one had a valve job done. Inaccuracies in the bench? This is before porting. I would think you can get more than 245 out of it but if thats what superflo says then thats probably right.

 

You might fudge that a bit with radius seats, rather than 15/30/45/60/75 cuts, and likewise helping the valve. I just don't believe that radiused intake seats are gonna work for 50,000+ miles, so I don't try them. I've always insisted that anything I release to joe public must be capable of going 50,000 miles.
The book and I were both going with 28" of test depression. However, atmospheric variables may fudge the numbers slightly. You know, humidity, temperature and barometric pressure. I was testing at around 72 degrees F. I forget what temp the book said.

 

Do you ever use the high end, high flow valves that are suppose to pickup a few cfm over other cheaper/standard valve designs? Any advantage in 8mm stem over 11/32 too?

Also what lift do you typically see max flow around 245 cfm? I've seen a guy post here saying 1.94 can go to just over .700 lift before hitting bore on a 305 bore, while a 2.02 cant go over .433". I wonder if you can find a fine line compromise with a 2.00" valve for low .500s lift because I've seen ported vortecs with a 2.00" valve do something like 265cfm, I'd have to look that up again but it was at some high lift value.

 

Looking at a Vortec 350 head, with stock '96 valves, I found 238 cfm at 0.475" lift. Just switching to stainless, swirl-polished, undercut-stem valves, with 30-degree back cuts, but NO porting or seat cutting, didn't improve peak flow at all, but down at 0.200" lift, flow improved from 121 to 133 cfm. At 0.300", it rose to 188 from 177.
Also, that 245 figure was with a 4.060" bore fixture. IDK what the max is with a bigger bore, but RHS is claiming 258 at 0.400" and 268 at 0.500" with a 4.200" fixture.
We had a 3.766" fixture, but I never used it. By the time I got it, I was long past building 305s, and firmly in the camp of: 350-or- nothing.
0.500" might be possible with 2.00" valves, and the low-lift should improve. You're probably onto a good thought, but with the larger valve comes a larger throat, and with that comes reduced velocity. Plus the increased cost.
At what point do you just put the L99 crank and rods in a late 350 block?
TFS did well with these intake ports, and there's not much potential left, for 305s. TFS released most of the potential. Getting any more flow into a 3.78" bore is the territory of LS6 heads on an LM7 stroker.
There's another 30+ HP hiding in the exhaust ports, with 1.6" valves, even just leaving the intakes alone. More so with a power adder.
How much investment is a 305 block worth?

 

I'd say the 2.00" intake valves would go hand-in-hand with a 3.75" stroke.

 

I was wondering the same. I know you are generalizing with the lift on the 2.02 vrs clearance but I bet it's much higher then that just looking at where the 1.94 makes contact. Also if you used this theory and also deshrouded the bore if the block isn't zero decked you could really see some gains I bet.

You should be able to technically fit a 2.02 intake and 1.60 exhaust in the bore and after examining small chamber high flow heads I'm not convincved that shrouding the valve on the sides of the chamber has a huge impact on overall performance. Since it is designed to spray at the center of the chamber. This is all theory of course.

Isn't there a guy on TGO with patriot 180cc 2.02 heads on a 305? Can't remember the guys name but I would swear it. It's a 12second 305 car I remember that much.

 

You can de-shroud the valves by "porting" the cylinder walls, all the way down to the top of the rings. Look at the old 396 blocks with 2.19" intake valves.
Then again, a 396 with 11:1, 4.10:1 gears and bias-ply tires with 5" of trewad width, in a 3200 pound Camaro, can afford to give up some low-rpm torque.
For a hot 305, I'd rather keep the 1.94" valves and have the freedom to spec the cam however would do best. Maybe use the Harland sharp 1.65:1 rockers, with a custom ground solid roller cam. Try for 0.620" intake valve lift.
For low-lift flow, with small throats, combining a 2.00" valve with 30-degree seats would do really well. Un-shroud it by going with a 60 overbore. It's a 305 after all, so take it 60 over on the first rebuild.

 

That's what I was talking about Atilla, deshrouding the bore down to the top ring.

I found that 2.02 1.6 headed 305 I was talking about. He ran 12.48 @ 109 NA with a Pro Comp headed 305. Later went 11's on nitrous. This thread is where I found the info, there may be a better one out there; https://www.thirdgen.org/forums/orga...est-305-a.html

running a xr276hr cam with 1.65rr I would say he got plenty of lift out of that with out smacking valves into the bore

 

This is what I was thinking... one time build so go max over and 2.00" valve should show good gains in flow but still allow some decent lift perhaps. If 1.94 can go .700" before hitting the bore and 2.02 hits around .430" then 2.00" should be near .500" on a stock bore assuming those values above are on a stock bore and a linear relationship. 0.060" over would maybe give abit more lift.

I dont know how close you'd want to take it to the bore and even if there is any benefit
taking it close since shrouding would occur but just an idea I had. If you can really pick up .300-.400 lift flow, then a good .480 lift cam should be ok to run and give good performance.

Now would that give you any advantage over a 1.94 valve and much higher lift of say .550"? It would be interesting to see. Probably not worth the effort tho to mod the heads for a 2" valve for minimal lift margin.

IF you can only get in the 240's cfm range, thats still plenty to do some damage as long as the rest of the motor combo is sized right.

 

Claiming 0.553" lift with just a 30 over. Doesn't specify head gasket thickness, block must not be decked, doesn't deny offset dowel pins, though noone asks.
Dart and EQ both offer 180 cc heads (and 200 cc) with 49-50 cc chambers, but they're 2.02 / 1.60. Both are iron, though both may offer aluminum.
I don't believe that other claim of 538 HP at 7800 rpm with mild 416s. We need video proof, including a tear-down right there on the dyno.

 

The info I have says the TFS175 heads are already over 240 cfm, even when tested with the TFS 1.94" valves, on a 3.766" bore.
I feel the valve-to-bore clearance should be at least 0.080" if reaching for serious rpm, and if de-shrouding to the top ring, then 2618 forgings being mandatory, forget 4032 forgings or hypereutectics.
If the owner is wiling to run a really high stall, then the throat size can open up.
I had a friend with a '67 Mustang, had a Roush-headed 302 in it, with a 3600-stall, C4, 3.80:1 and slicks, it was hell to live with, but when he launched, THEN the converter was just incredible, and the heads didn't seem too big. ( However, I then proceeded to make my Vortec 355 '88 Camaro run him with a 2200 stall, 700R-4, 3.73:1, and street stickies, just to prove a car didn't have to be hell to live with just to run hard)

 

Any fool can hack away at some heads....

Do you also plan to provide Before/After flow numbers?

and proof of EVENLY matched port flow..

Either way, sounds wishy washy..porting heads by hand is time consuming and labor costly...gotta be the first time ive ever heard of someone offering to do them for free.

 

Ah, my stupid nemesis returns.
You, bird-boy, are probably the only person participating in this thread who does not comprehend that every CNC port design out there was created by hand. And not just any hand. There are probably 10 people in this country who have the gift. It's not just practice. It takes a natural knack. I have it. So does Tony Mamo, Joe Mondello, Jud Massengill, and so on.
And I am the only one on this forum who both shows and tells what to do to various heads, and what it does to the flow, according to a SuperFlow 1020.
Port-to-port consistency? No human can ever rival the CNC, but you can never rival me. Nor can 99.99% of the members of TGO.
Doing it without monetary compensation doesn't mean NO compensation.
What value education? I freely admit I've not yet had a pair of these particular heads in my little pink paws...yet.
Any fool can hack away at some heads? Yes, you are proof enough of that.
Don't like my disrespect towards you? Then stop F#&*ing heckling me, there's NO good reason, you *^%#$, O*&%(*7-(&^$*%$, immature, irresponsible, &^$%&^(&*!!!

 

I totally forgot...

You are the self proclaimed FAMOUS GOD of building engines, with very little factual proof to backup what you claim, and who you are..

Cuz all the famous engine builders are out of buju nowhere utah, and they all build greasy nasty cars with their tools laying in the dirt..TOTALLY makes sense.

Keep on living in your fantasy, trying to impress the young kids who are on this site...

 

I had to look into it and it doesn't look like he used any wizardry to make it work. The heads were even milled to 60cc.

 

So what thickness were his head gaskets? And did the dowel pins ever come up?

 

BTW, I've told you this before, you forgetful amnesiac, I have every right to take any and every legal step necessary to hide my true identity. I am not going through all the hell that Tony Mamo is going through on ls1tech.com. And he's not even dealing with any health issues. Tony is the prime example of why most forums don't have famous members revealing themselves. They're there, I know their real names and their user names, but they see the grief I get from jealous losers like you, and they play ignorant.

 

You keep calling into question things that I've already proven. Much of it months before you arrived. That's unforgivable. You have NO business attacking me, and I have every right to fight back. And again, you never actually help anyone. I do.

 

Nater, my apologies for my part of the crap that bird-boy can't help but re-starting over and over.

 

How have you already proven anything with these heads?

i asked you if you were going to provide him with before/after flow measurements...you dodged that question..

i asked you if you were going to provide him with proof of similar flow numbers from each port...you dodged that question...

Im not attacking you, im questioning you, there is a huge difference, but it seems you're too blinded by your self proclaimed spotlight.

Ps, i help plenty of people. both in real life, and on these forums..and ive been around TGO since the beginning of it..so, carry on thinking i am some 17 year old newb or something.

 

Before I was Atilla, I was a senior member here under another user name. I'm not a Johnny-come-lately.
Your questions aren't gonna get answered publicly. You're bad enough without me adding fuel to your fire. Fix your attitude, I might start answering you. Nor are you gonna get copies of my PMs to Nater36, unless he sends them to you.

 

I do not understand whats so hard to answer about my questions, i simply asked if you had planned to factually show/prove flow, and flow improvements via YOUR port work, and factually show/prove equal {within reasonable human limits} flow numbers via each port...Normally People/Companies who do extensive porting/building etc etc, are always more then enthusiastic to provide flow numbers.

Theres nothing that needs fixed in my attitude, in a world where it seems like everyones out to ...someone, i question things, plain and simple.

You getting all offensive and defensive about things i ask you, raises huge red flags...

 

Damn, bird-boy, why you gotta be like that?
Atilla obviously feels agitated by you, yet you keep on typing!
He's answered every question I've ever posted, you haven't answered even one. And not one of his answers has been even remotely questionable or controversial. Do us all a favor, including yourself, and keep out of any and every thread that Atilla decides to participate in, he IS far more helpful than you.
I also apologize to Nater.

 

Yeah, I noticed that I missed him by just 5 minutes. Kind of frustrating. You have every right to post as you please, of course, but there was no upset-typing here until you chimed in. If all you can bring is discord and hurt feelings, then how is that of any benefit to anyone? Even you?

 

Nevermind, I see it now. You want Nater to think you're saving him from being scammed by Atilla, right?

 

And further, I am gonna send Atilla some heads, just to see if he's great at porting.

 

around 250 cfm-275cfm

 

To some, maybe not....but certainly i'd be upset

Lets not keep the attacks public. If you have problems please take it to PM's, this stuff clogs threads which can usually contain good information.

 

Didn't see anything like that snooping through the guys post kinda feel like I stalked the guy a bit he hasn't posted in a while or I would send him a PM.

I can't imagine him spending the money to mill them down 4cc and then using anything but a shim head gasket.

Orr89RocZ is that .433 valve to bore with the 2.02 valve accurate or a estimation? I have a bare 305 block on my engine stand right now but no 2.02 valved heads to check it with.

 

Who cares about what flow is picked up. I'd like to see a baseline time slip BEFORE and one after.

SOTP is hard to judge because it's typically in the mind of the person spending money.

Is there any way to do a before/after timeslip?

Reher Morrison and others have PROVEN that porting just to get more flow does NOT result in more power or better performance. In a story I posted they took 30 CFM OUT of a head and made more power.

SO I'd like to see the only thing that matters, before and after of time slips. SOTP is meaningless and typically imaginary.

A sewer pipe flows a lot of air, I wouldn't want it for a head.

 

i agree completely as flow means nothing really..

But then what happens if these heads get ported, and the car runs slower?

 

Not true. This Board has rules that are expected to be followed.

Stay tech and on topic, or don't bother posting.

 

Well, if the car goes faster, the "how to port a head" thread has some meaning.

If it goes slower, then it is completely worthless.

Good to know beforehand.

Atilla seems to put a lot of time and energy into this stuff, I'd like to see him get results that NO ONE can question..the only way to do that is timeslips.

 

Doesn't have to be timeslips, can also be dyno curves.

 

Basically what ive been getting at in this post, along with others...

but for whatever reason he loves to think IM the one attacking him..

 

How do you measure that? FLOW? That's useless.

Serious, how do you come to that conclusion without a time slip? There's no way. I can give my 7 year old a dremel and a head and say "go at it" and I gaurantee he gets more flow. You wanna bet he doesn't get more power or better time?

So what's your basis.

 

Dyno curves mean NOTHING.

Its simply bragging rights, ive seen cars dyno very impressive numbers, and then are complete turds at the track, and vice versa.

i went 12.2x's with 299rwhp/401rwtq..with a drag radial through a banger, never in a million years would i have expected those times.

Right now my car dynos mid 360's for power..and goes nowhere, but i still have bugs to get worked out. Dyno numbers to me are meaningless, i use them for tuning and for checking my equipment.

 

I don't put a lot of faith in dynos, as noted above,there have been cases that cars are 100 HP apart and run the same times or the lower hp one better.

At the end of the day, performance enhancements are made to go faster, so the clock is really the only real determining factor is the clock. Who can argue that?

Everything else, means nothing, it's just a circle jerk.

 

Man you two need to just forget about responding to each other!!! Seriously! Just ignore each other because, A.Neither one of you are willing to drive to another state to "prove" anything and 2.Neither one of you are cutting each other slack of any sorts so being friends aint gonna happen. Just respect each others peace, if not each others at least your own!

 

Well lets not have a double standard then if you are using Reher Morrison dyno results to validate head flow is useless. He ported the heads then dyno'd the motor lost flow and picked up HP. And he only talks of peak flow.

There's much more then HP at play in getting down the track. Flow is not the only thing that makes power so of course changing it doesn't always effect power.

There's also no need to reinvent the wheel, it's here, it's done. It's called CFM it's how we measure how much mixture can move in/out of the motor at various stages of combustion. You are comparing the cause to the effect.

 

But fact is, just because the heads flow more, and even if they DO make more power on the dyno...it does not mean the car will get down the track quicker, this has been proven time and time again..how many people do you see with decent times, and disapointing dyno numbers?

I have a buddy with a 308 sbf in a gutted notch,victor intake,tfs heads,longtubes,banger trans..etc etc..

car goes 11.40s on MOTOR...motor dynoed 268 and like 304rwhp corrected..meanwhile, my 93 LX hatch with a 306sbf,performer efi intake,performer heads,shorty headers,banger...dynoed 330s for rwhp..and only ran 12.0s POWERSHIFTING it on a slick.



The op needs to bolt these on,get the car tuned...take it to the track and see what she does...get them ported, and only leave the head porting for the "variable"

that will tell the story.

 

I know what you are saying but a drag race isn't a motor sitting on tires. One "off" part could ruin it. And in the same respect one right part could make it great. Stalls, slicks, rear ends, transbrakes, ect.

The point that InjectorsPlus made about the race motor making more power with higher volume poorer flowing exhaust runners is a bit interesting though. Maybe the flow bench doesn't simulate scavaging well? And also the explosion is forcing gasses into the exhaust runner may not be simulated.