urbanhunter44

iTrader: (3)

These were found on LB9 and L69 cars right?

Will these bolt up to my 85 LG4?

I'd like to find some good heads to rebuild and port/polish, and squeeze some more horse out of my 'maro.

And any suggestions on good parts for my head rebuild?

Will 1.6 rockers work with my stock motor?

Thanks guys!

F-BIRD'88

You may have 416 castings now.

switching to 1.6 rockers may require that you lengthen the pushrod slot in the head that the pushrod runs through.
the increased ratio moves the pushrod closer to the rocker stud and may rub in the slot.

Stekman

Yup, lift the valve cover on your heads and look at the casting number. They tell all. If you want to have a running car while you work over some heads, they (305 heads, 416, 601, or 081 castings) can be found on the classifieds or in the junkyards. Between the 3, you are bound to find something.

As to how to set them up, that would depend totally on what you plan on using for the rest of the build.

ME Leigh

416's came on LG4's and L69's. 601's also came on L69's. LB9's will have 081 heads.

azvolfan

I put 416's and 1.6 rr's on my '92 Camaro and did not lengthen the pushrod slots. Could this be why I can only get a 16.2 out of my setup??

Stekman

Probably not. Did you change the cam at all? If not, that's why. TBI's got real small cams and low compression.

azvolfan

Yep. Went with the L98 from an '87 350. Which would explain my tuning problems.

3.492rs

Hey this is urbanhunter44 on my buds computer.

What I want to do is just get some more power out of my car by rebuilding and port and polishing new heads. (By new I mean junkyard ones that aren't f'd up.) And get this power without changing the cam, but I may change it eventually, as well as the intake, but not now since I don't have the money.

Thanks for the pic by the way Fbird.

So which of these heads is the best for what I want to do?
How far do I have to lengthen the pushrod slot for 1.6's?

Thanks guys!

IROCaholic

If I were you I would get the heads milled a little to up the compression. The two major things hold the Lg4 back(enternals wise) is compression and the cam. They came stock with like 8:6:1 compression. Bump that up to like 9:3:1, add the ported heads, and an XE262 cam and that will give you alot more performence to your car. Add a good intake and full exhuast and I bet youll pull at least 260hp at the flywheel.

F-BIRD'88

IMHO:
The 416's are great to port and up the valve size.
go with 1.94 intake valves. On a 305 I would stay with the stock 1.5" exhaust valve. (get new ones)
The 081 TPi 305 head has just as much potential and a nicer plug position.
I'm not real big on the 601's. They can and will run good with porting and larger valves but from looking at the ports in stock form I'd say they will not come out s as
good as the other two. The combustion chamber is much more shrouded also.
I've gotten mid 230cfm intake and 180+ on the exhaust with larger valves and full porting on the 416's.
One set flowed 242cfm. The worstcase effort came out to 224cfm. on the flow bench.
You really want to re-cam the motor after porting the heads as most of the improvement is in the mid to top end power range. The motor will like more valve lift.
Any thing from .450" to .510 will work. Match the cam's duration to the rpm band you want the motor to make the most power in.

Forget the 1.6 rockers. get a new cam. it will have 3 to 4 times the effect on the power. for the same $$$
going .125" longer will be more than enough.
Even the cheapest hi-performance cam and lifter set will
give a great improvement over the stock cam. And out perform a rocker ratio swap.
Buy what ever cam brand you can afford.
The push rod should clear the end of the slot by .060" at all lift points.

I use a 5/16" rat tail file in an electric drill to do it .
Just be careful not to widen the slot.

here is a link to a typical budget street 305 buildup with ported 416 heads etc.

TexasB4C

iTrader: (1)

will the 416s work fine on a 350 with TPI
FBIRD88, can you look at my recent post called cam choice and let me know what you think of it
thanks
tim

mw66nova

iTrader: (13)

CHANGE THE CAM





nuff said

F-BIRD'88

It's a little big. TPI motors with their small/long runners are all about low/mid range torque.
keep the cam's rpm range (duration in sync with the induction system. I'd look for one around 205-215 intake duration and 212-218 exhaust duration. wide LSA (112-115)
any thing around .450/.480Lift is enough. Don't get carried away with big numbers, This is a "torque motor"
If you want to have a "high rpm motor" (big camshaft) then change the intake manifold to a short runner style (LT-1,Ramjet,Stealthram,MiniRam) The intake manifold and camshaft have to work together.

TexasB4C

iTrader: (1)

well i just bought this one off of ebay

int= .479 Exh.=.501 with 1.5 roller rockers

Dur.= 222 232 @ .050

what do you think?

F-BIRD'88

it's a big cam for a TPI motor. It will likely need Chip tuning,
it will want a higher stall converter and high gearing.
It would favour a siamesed runner TPI (higher RPM range)
and head porting
it will need upgraded valve springs and head machining
It would work a lot better on a TPI moto with a LT-1 intake swap.
Unless you are going to build a max effort highly modded TPI motor I'd.
Sell it or use it in a different motor.

What are the numbers stamped on the end of the cam?

TexasB4C

iTrader: (1)

im not sure what type they are but ive got dual springs, the type with the center coil also, i plan to have them checked also,
what type of rocker studs do i need to get, i plan on getting roller rockers later on
lets see......
i plan to get 3.73's for a broken 3.73 posi i have on my porch LOL
and theres a local guy from the boards here that does chip tuning so i plan to get that done too, im a student at UTI so ill be running the dyno while tuning it hopefully and ill be posting my results so everyone can see, and as i do more ill post more dyno ...... and track times
well im stuck with the cam mentioned above...
i saw all the cams tpis had and looked at the hotcam and some other TPI cam specs and went with this one which had a little more than the hotcam and a little less than the ZZ 9X by TPIS

int= .479 Exh.=.501 with 1.5 roller rockers

Dur.= 222 232 @ .050

i have headers with dual cats flowing into a single flowmaster, ill be doing a flow check on those 416 fullly ported and polished 1.94/1.5 heads and ill post the results for that, and ill be porting the plenum and runners, the air boxes were gutted from before with K&N filters, and i just bought ram air boxes off ebay for 14 bucks, i have an adjustable fuel pressure reg. .......your saying all that wont be enough flow for the cam I bought?
if not what else could i do besides getting a mini ram or super ram

thanks for the tips so far
tim

dont know the numbers on the end of the cam, didnt get it yet
but the part number is Speed Pro CS-1152R i found it going through the federal mogul website herefederal mogul
it says it has a fair idle

92blue

iTrader: (1)

The 416s on my car came off an 85 LB9. I removed them myself, so I'm not going by what someone told me or anything.

RB83L69

Right, the 081s didn't appear until 87 on LB9 (and also on LG4 & L69)

92blue

iTrader: (1)

There were LG4s and L69s in 87? Really? I wasn't sure what was the last year for them, but I was under the impression it was 86.

Basically, the 081s are very similar to the 416s with the exception that the 081 use centerbolt valve covers, and the 416s use perimeter bolt valve covers. The 081s will also have the late model manifold bolt pattern.