i8myz28

iTrader: (1)

i'm running my 416's with a home port n polish but i still have stock valves, i'm buying a set of 083's going to port n polish them and install , will i see a big gain in hp..?
the cam im running now has 420/442 lift any ideas how big of cam i should upgrade too, i'm also porting my intake so i'm hoping for some more rpm's.....

please help me guys with some advice....thanks paul..:help: :huh: :hmmm: :thanks:

Tibo

iTrader: (15)

Stick with the 416's. If you have the stock valves you are giving up a significant amount of airflow by not going to the larger 1.94 valves. Do you have the 3 angles done on them?

RB83L69

The 416 and the 081 are essentially identical; they're just the perimeter-bolt and center-bolt versions of the same thing.

So, if they are exactly equally prepped, you will gain exactly nothing by swapping them, because they are exactly the same.

They both have 1.84" valves in them. I don't know what all that other is about.

That said, if you put a set of heads on a 350, you should at least put the stock 350 valves in them, or of course the motor will produce less power than a stock 350. That would be 1.94" intakes.

Best advice I can give you, is to get that ancient generic carb cam out of there; and put a TPI-specific cam back in its place. That cam probably makes your combo slower than a stock TPI cam would, in a stock TPI situation; which yours pretty much is, except for the exhaust.

i8myz28

iTrader: (1)

i have no money put into the 416's except for home porting n polishn...dont really have the 250 or so to have bigger valves installed...should i just get a bigger cam n keep the 416's or i've been racking my head for weeks trying to figure out a good plan...

i8myz28

iTrader: (1)

the new heads will be 083's NOT 081's....

i8myz28

iTrader: (1)

the cam is from summit its the tpi cam kit part#g5000...

92blue

iTrader: (1)

I don't recall off the top of my head, but aren't the 083s the 350 TPI iron heads? If so, then they are pretty much identical to the 416s except they have larger valves.

RB83L69

OOoooooopps, my bad.... I thought I read 081, which is the 305 TPI head. You're right, 083 is the 350 TPI head.

So in that case, you will drop your compression, but pick up a little flow; probably not a whole lot of change overall. It'll lose a bit down low but pick up a bit up high (4000-4500). The loss will probably be more noticeable than the gain just driving around, but the car should run the 1320 about the same.

That's just not a very good cam. A very very similar grind is typically sold as a "RV cam" for people with carbs. Works OK for cars with restricted intake and exhaust, stock converters, and low numerical ratio rear gears. Only difference is, they opened up the lobe separation 2°, and called it a "TPI cam".

Look at some modern cams with some actual R&D done on them; such as from Comp, Lunati, Crane, etc. You stand to gain ALOT more from that, than from that head swap.

i8myz28

iTrader: (1)

so id be better off with my 416's with stock valve and just getting a cam like xe268 or so...

RB83L69

No, that wouldn't be AT ALL the right cam. One more about like this

I think you'd probably do better with the combo of the 416 heads and a better cam, than the combo of the larger valves, lower compression, and less-than-ideal cam.

i8myz28

iTrader: (1)

that cam compared to the summit cam isnt much different the lift is only a little bigger but the duration is longer wouldn't i want a little more lift than the 256 but u think the 268 is too big need a little kick in the brain to understand the cam thing please fill me in...

ljnowell

More to it than just the numbers. You have ramp rates and such to factor in.

sellmanb

If you reaaaally dont want to install new valves so badly that you're willing to re-port a 350 head instead (many many hours of work), then go right on ahead and do that. Then take it into the machine shop and have the head grinded down so that the CR is about where you want it.

i8myz28

iTrader: (1)

well porting n polishing don't bother me so thats a toss up, i was tring to factor the amount of time of sending the heads to the shop and the price of having the valves done, no one wants to leave the motor topless for any amount of time and the price of having it done i just though doing this would accomplish more by putting bigger heads on, but listening to you guys on dropping in bigger valves on the 416's..i'm going to think harder and make a couple of machine shop calls...and right now is not the time in new england to be working on your car outside.....BUT i still need a lot of advice on the cam to upgrade too with happy gains.....

please guys i need cam advice.....thank you for you guys thought and guidance.....did i mention this site rules........

Tibo

iTrader: (15)

ZZ4, LPE 211/219 or 219/219. For daily drivers. Maybe a comp 224/230

i8myz28

iTrader: (1)

will i need to tune my computer if i do a zz4 cam ..??
if so im lost in that department too...

Tibo

iTrader: (15)

You do not have to tune a ZZ4 cam provided it is in a 350 or larger. The computer can adjust to it, and it will not throw up codes. But as always, tuning is best.

i8myz28

iTrader: (1)

isn't the zz4 a roller cam...???
my block is non roller any new suggestions , please...........

Tibo

iTrader: (15)

Yes, it is a roller cam. I missed that you had a non-roller block. '87 is when they started. Summit makes a TPI cam and other good cams that are very similar to comp cams for 1/2 the price. Just go with a range that was stated above.

i8myz28

iTrader: (1)

its been a while since i posted this. i found out its more $$ to put bigger valves in the 305 heads than it is too have the 083's shaved...but do you guys think i'll see more of an improvement with a bigger cam like an xe256 and stay with the 416's..please learn me some more....thank you guys for all your help

gmgod

Your sig says you have flat top pistons. As long as your piston to head clearance is around .050 inch your 64 cc heads are just right for what your doing.
If you don't know, measure how far down the pistons are in the bore at tdc and choose a head gasket that when added to the measurement you just took equals .040 to .050. That should leave you with more than enough compression with iron heads. I think I would even run the comp xe262 with a 112 lsa to try and bleed off some low rpm pressure. High octane gasoline is too expensive these days.

Penix

Flow wise, you will get much better results from the 083's for alot less money, BUT, if you want a set of 305 heads that will out perform both of these, check out a set of 601's!!! These are the king of all 305 heads, and it's all in the combustion chamber design. Check it out below...

Here are the 601's:


Here are the 416's:


See the difference?

Fully ported and polished, the 601's will out perform even the 083's with the same amount of work put into them. The problem however is that the 601's have a chamber volume of as little as 53cc's. So unless you commit to dished pistons I would seriously suggest using the 083's.

Now then, if you want some SERIOUS stock upgrades then get yourself a set of 041x heads!!! There is a set on ebay right now: http://cgi.ebay.com/ebaymotors/041X-...em130154476727

The 041 and 041x heads are basically a 64cc version of the 601's but better, and they even came with both 1.94"1.50" and 2.02"/1.60' valves stock! Best cast iron production heads you can find! And yes, they are in the "Camel Hump" family.

five7kid

iTrader: (14)

Other than this being TWO YEARS OLD. . .

Saying 041x's are the best cast iron production heads is a bit of a stretch. Can you say "Vortec"?

Penix

True, should have been more specific. Aside from the vortecs...

LOL, I didn't notice how old the thread was, that's hilarious! Oh well, maybe it'll still be able to help someone out.

I don't know why but I still forget to include Vortec heads when I mention production heads, probably because they require special equipment in order to run.

five7kid

iTrader: (14)

Special intake. Replacement springs and perhaps valve guide cutting depending upon the lift of the cam.