Hi guys i've got a stock lo3 in my 1992 maro rs. I was wondering wondering what stock ratio rockers were on this engine? I was also wondering how much higher i can go with everything else being stock.

I also wanted to know if i would need hardened pushrods. Anything else that i might need would be great.

I beleive stockers are 1.5 ratio self aligning 3/8 rockers but, tell me what they realy are i'm not quite sure.

Btw should i notice a noticable gain in peformance by swapping to a higher ratio rocker (more lift) and going roller, or should i just leave it alone. I don't want to do a cam swap and rockers are fairly cheap and real easy to install. so opinions are appreciated.

Would i have a noticable ill effect on the computer by sticking with the stock prom and not tuning it right away after adding higher ratio rockers?

 

any1? I'd just like to know for sure what ratio rockers i can get?
(i beleive i want 1.6s)

if i need hardened pushrods?

What size studs (3/8 or 7/16)

and anything else that i may have left out for this swap that i would need part wise or need to know knowledge wise.

 

Your stock rockers are 1.5, 1.6's are your only other option for a SBC. You can get away with just swaping them and leaving everything else stock. The cam in these motors are TINY, so 1.6's are a good upgrade if you don't want to do a cam swap. It'll be completely drivable after the swap, but you won't realize the engines full potential till you do some chip tuning. You'll pick up around 5-10 hp with the rockers, and probably be able to unlock another 5-10 with tuning. Thats assuming that your stock tune is good for what you have.......which is a bad assumption, you can probably pick up 10-20 hp with the tune alone. It would be worth your time to start datalogging your car now and get an idea of how it runs ecm wise. Then when you swap your rockers you'll be able to see what changes and where to change things in the chip. Granted your probably not ready to jump into chip burning, but the sooner you start trying to understand how the ecm works the better off you'll be.

 

t/y i appreciate the reply. I think i'm going to use that program that records how it's running and just send it off to have a chip burnt. I'm sure it won't be perfect but, i realy don't understand the ve tables and timing and such as well as i should to do it myself.

I don't plan to do much at all to this motor for at least another year or 2. I want to port and rebuild the tb and mildly port the stock manifold (barely at all) put new filters for the injecters and o rings in it and the roller rockers. It already has an open element air cleaner. after that i'll save for headers and be done with it for the next couple years (engine wise).

i'll buy me a strut tower brace and subframe connecters after i get the real mild engine upgrades done. Then i can move on to beefing up the drivetrain for when i'm ready to build up my puny 305 hehe.

yes yes i know blah blah stick a 350 in there you will be happier so on so forth... I still like my 305 and am going to stick with it.

 

can any1 confirm what i would need then?

So far i know i want 1.6 ratio rocker arms. I've been told now that i won't need hardened push rods and i'm guessing i also won't need the guide plates.

What i need to know is if the rocker studs are 7/16 or 3/8?

are they self aligning?

is there anything else i should replace for down the road durability while i'm at it (this needs to be strong).

less durability than stock is not an option because, in a few years this motor will be pushing close to 400hp to the flywheel is my best guess.

 

You need 1.6 self alligning 3\8 rockers. You can re-use your stock pushrods.

As mentioned your stockers are 1.5. 1.6 rockers on a stock LO3 really helps fill the chamber and many people see significant gains on an otherwise stock motor.

You are smart in making sub frame connectors your first mod. Also, these rockers can be used on any larger small block so you aren't wasting your money.

 

thanks a lot i remember reading that they were 1.6 self aligning 3/8in rockers from somewhere but, when i tried to look back to confirm i was correct, i couldn't find it anywhere. T/y for the info and i'm sure either way even if i don't see sotp gain in performance i'll be happy with the upgrade.

(+ the tb and intake manifold will be ported and rebuilt and such while i do this swap to) so i'm sure i will notice a gain (the injecters patterns don't seem quite that great anymore) could use a thorough cleaning i'm sure.

Does any1 have a certain brand that they think would be good to go on my motor? (i like quality parts at reasonable prices). While looking i found comp magna 1.6 rockers that i was thinking will probably be my choice (stronger than aluminum, decent price, and a good brand name.) Heres what i was thinking of, http://store.summitracing.com/largei...rt=CCA-1318-16>comp cams magna 1.6 rockers</a>

ps. i wouldn't be buying the rockers from summit i saw an ebay store selling them for like $150.00 new buy it now price.

 

I would look for a set of roller tipped steel rockers that can be had for around $100 or less. Full bodied aluminum rockers don't have a long life span and won't provide any greater result than the cheaper steel ones. The HP per $ ratio is in your favor with the cheaper steel ones.

 

Stay away from ProForm as well. I haven't heard very good things about them. Porting the TB is a good mod, but it's one of those that you won't feel by itself. It just compliments other mods that much better. I'm sitting on a ported TB and Edelbrock TBI intake (50mm) and I'm starving for air at the moment with my heavily modded 350. Thus far fuel doesn't seem to be an issue, but airflow does.

 

I would think about skipping the chip from TBI chips, and put that money towards exhaust, or at least get the burning equipment. You can slowly learn what to do over the next 2 years, and be way ahead in the end.

 

Brian from TBI Chips gave me a chip via email that I ran for over a year to no ill effects. Was it perfect? No. But I drove my car for a year until I had time to go up there and have him tune it personally. The results of course are far better now, but given my job, deployments, family issues, school and countless other things; I'm am quite happy with the service that I've recieved from him. Mail order chips serve their purpose and if one happens to be lucky enough to live near someone who can teach them or do it for them, more power to them.

 

The key to your success was that you eventually got him to tune it with the car in hand, I just think that he would see more HP by putting his money into his exhaust or learning to do his own.

 

i appreciate the advice i will be staying away from pro-form.