I have recently come into posession of a car powered by the jaw-dropping 305 LG4 150 hp super-engine. It's in an 84 monte carlo, but since there are no super-cool monte carlo boards, and the same engine is featured in some camaros, i figured it would be ok to ask questions here!

The initial plan is to get rid of all the ecm controlled stuff, so I'll be switching to an older-style distributor and a non computer controlled carb.

What is a recommended carb/intake to switch over to on these engines?

So far the best i've been able to select is an edelbrock performer intake and a holley 670 cfm carb.

What is required to swap out to roller rockers? The arms themselves, springs, retainers, anything else?

any info is much appreciated.

 

you need to be more specific with your ?s if you want answers..as far as intake /carb goes is your engine bone stock?u rebuiding it?if its stock dont go much crazier than what you mentioned ,a performer and a 600-700 cfm carb...as for switching to roller rockers..well you can go to the steel roller tipped rockers but if you wanna go full roller rockers with the lg4 you ll need adjutable valve train and also bigger studs which means removing head ,machining them for new studs(not worth it on this engine) or switching to heads with an adjutable valve train already(again not worth it on this engine) sorry to be a kill joy but go with roller tip or forget the whole rocker deal

 

It's just the stock engine, not rebuilt, just need to perk it up while saving for a 350.

Roller tipped rockers, are they worth the expense? What other components will I need for this swap? The engine will be stock heads/internals, and will not be cammed. I only plan on doing intake, carb, headers, and roller rockers if possible.

Thanks for the info, not a killjoy at all. Just new to this engine and trying to learn what I can.

 

honestly,as much as you wanna go fast dont send squat on this engine..period..unless theyre parts that are going to be used for the 350...exhaust for instance can be used,unless you going to tuned port vs carb then the headers are adifferent..dont do anything with your heads now cause you aint using them on the 350 anyways,or at least i wouldnt and you shouldnt.intake carb will swap but dont be expecting to be floored in your pants by increase.heres what it boils down to..you aint go go much faster with simple bolt ons..where your real power will be made is thru the heads and the head work,comp ratios and camming...but you aint going to touch that on your 305 becuase it aint worth it and you cant reuse it on a 350..so enjoy what you got,save it all for your 350 build and do the 350 right from the start.....thats the honest to goodness truth...heres aprime example,ok you bolt on a intake carb..wow youll gain maybe 10 hp if your lucky,and say there was amagically way to bolt on roller rockers to the used lg4,you probably wouldnt gain much at all given wear and tear..so in the end youll gain very little and be disappionted...btw roller tips ok for a tight budget but they aint much less than a full roller set..

 

There is no reason to stick on a Performer intake on it. Even though better than the stock iron intake that you have, the Performer RPM has been documented to make another 20HP with better low end torque than the Performer on a otherwise stock LG4.

Do a search on Car Crafts LG4 buildup, or 325HP 305, 400HP 305, etc. An LG4 in good running condition, with the Performer RPM intake, a good carb like you mentioned, full exhaust (headers, 2.5" dual or 3" single), and 1.6 roller rockers will really wake that little 305 up. Some may find it hard to believe, but 210HP is not out of the question.

Also, you can go with a full roller rocker setup WITHOUT the rediculous work mentioned above. The only thing you'll need is taller valve covers. The cam on this engine is so small even the stock press in studs will hold up.

And unlike anthony714 recommended, throw all the bolt-ons you want at this LG4. Everything can be reused if and when you go to a larger inch engine. I'd also recommend that anthony714 do a little research on the SBC in general.

 

Nothing wrong w/ hopping up an LG4. If you know what your doing, you can get a lot out of that LG4 of yours

 

hello........dont you see the point..one those magazine build ups are 1,professional builds, and 2 on a new engine...hes taking a ratty 305 from an 84 ,god knows how many miles are on it and you recommend he spend money on all these incredible bolt ons which aint going to add much to a worn out engine except blow more blue smoke????.and yes i stand corrected on rockers,i was thinking back to my ford days but who in thier right mind would spend cash for a set of rockers for a 84 305 lg4?????and you really think slapping a performer on that engine right now will add 20 hp???????please i have great land to sell you also,,dont mind the swap areas....dont be one of those guys who drool over all these advertised hp increases from a simple part,heck if that were true your engine would make 500 hp from bolt ons alone!!!!!!!!!!and yes parts interchange from all small blocks but you going to use a 305 head on a 350?and he was looking for a 600 range cfm carb..ok fine but maybe when you go tothat 350 you might wanna look into a 750??????or instead of 1 5/8 inch headers on his 305 he might wanna go to 1 3/4 for a 350 and instead of a 2 1/4 exhaust on a 305 he might wanna look into a 3 incher????point is build a 305 fine,but the man said he is doing a 350 soon.i recommended that he just concentrate money and effort strickly on that engine and dont waste any time or money on a worn down ratty old,smoke belching 305 that aint going to get out of the 16s regardless of what you bolt on.................

 

^Yup, 300hp wont make anything short of 16's
And why in the HELL would his 305 smoke if he rebuilds it????
And why in the HELL would you get 1 3/4 primaries for a 350???? That is WAY to big; stick w/ 1 5/8.

 

hey jag weed,try reading his second post..he says its stock,not rebuild,just waiting till he builds his 350....and his internals and heads will be stock...so you want him to build on that platform???you go girl..........

 

hahaha, yeah that 85 guy has no idea what he is talking about. I had a 305 in my 91 and I am building the entire car over. Best thing u can do is toss the 305 ASAP, and save every penny to buy that 350, hey u might even save enough to get a 383! Anyways people who post, make sure u read all the older posts so u don't sounds like an idiot

http://members.cardomain.com/dennisbernal91z

 

ahhhhhhhhhh finally a man with with some brains..btw nowadyas building a 383 dpending on how you wanna build it dont cost more than doing a 350

 

Thanks for the "positive" reply, marc.

the reason i was considering the performer as opposed to the RPM was because i wanted to keep my power in the lowest rpm's possible. if the rpm makes more torque too, sounds good to me :P

what will i need to swap to roller rockers? i was wondering about the size of the springs too, any way to tell without taking them off?

and i'm not just saving up to buy a 350, because even if i had a super pimp 427 sbc right now, i have no place to put it in. i live in an apartment complex. boltons are fine, but i think pulling an engine will have to wait till i can find somewhere to rent me out a work bay.

the idea is to perk up the engine as much as possible, without going overboard, while the rest of the car is crafted into perfection. rear end, trans, brakes etc. thanks for any info, guys.

 

AHAHAHAHHA... ok newb, shut the **** up. Obviously I *DO* know something if my "piece of trash 305" is making damn near 300hp, prolly a little over
And since your a new piece of **** here, I will be nice. This part of cz28.com, the thirdgen section, is NOT about making fun of people. This is a business-only section. You wanna be a smartass go to the Lounge; I guarantee you they will lay your *** out. Just because *your* an idiot and can't build up a 305, does NOT mean nobody else cant.

 

Wow, talk about someone who needs a clue... I feel sorry for your ignorance, so I'll assist a little.

1. That 305 mentioned above was not a new engine. It was a 1982 LG4, and had over 80,000 miles on it. Had you actually looked into it as suggested... Car Craft 305 buildup 2 things to note. First, the baseline torque is a typo, it should read 265 and not 165. Second, the results would be nearly identical with a dual 2.5" system.

2. Which brings me to what will produce power on an LG4. Again, look into that article. Or you could head over to thirdgen.org, if you're capable, and check out who has achieved decent results from an LG4. There ARE stock heads/cam LG4s running 14s. I had mine running low 15s before the 350.

3. Yes, you can use 305 heads on a 350. And in fact, LG4 castings will make more power than your average smogger 350 head. More compression and better flow. LG4 heads have a ton of potential in them.

mourningyou - The only you will definately need for full roller rockers is taller valve covers. The rockers should not interfere with anything on a stock setup. Larger diameter springs can cause interference. Only other thing to lookout for is pushrod to head interference on larger than stock ratios. And as undercammed as this engine is, 1.6 rockers will make a big improvement.

 

^Now *theres* someone in the Know
But on a side note, a stock head/cam LG4 in the 14's? Thats quite insane. Can I ask the mods that put it there?