77 malibu classic

i will continue my topic from the introductions section here, since i feel its a more apropriate place.

i just bought a mercruiser 305 engine a few weeks ago, its completely disassembled and im planing on rebuilding it. i only bought the 305 because it was very cheap and i need an engine to practice on before starting some serious build. its interesting that it has 55 more hp than a chevy 305 to begin with. anyone knows why? it is reverse rotation, so ill have to replace the camshaft and the distributor. btw, does anyone have any experience with those rebuild kits from ebay that contain pistons, cam, lifters, chain.......


i also bought a rebuilt th700r4 tranny today that will go with this motor. i searched the forum and found some topics about the th 350 / th 700 swap, it doesnt seem that hard. i have a question about the kickdown cable though. which is the most apropriate lenght for our cars? and how is with speedo, does it fit? i read on a 4x4 forum that it is a must to install an additional oil cooler, is that just for offroad aplications or for street cars as well? how about the lockup converter? i figure that since offroaders use bigger tires it must be harder for the tranny, but i have them "highway gears" in the back (dont remember the exact ratio, but i know that its pretty low) and that might put additional stress on the tranny too.

i was also thinking of changing the rear end ratio, which do you think is the most appropriate? (car is used as a cruiser, but id still like it to be reasonably "fast")


will be posting some photos of the car when i get home, im off at college now.

if it is reverse rotation double check to see if it is not an Olds 307 first

Thanks for keeping us updated. As for the trans cooler, if you run your engine a quart low on oil all the time it will still last a while, but you would be better off keeping it at the right level. Its the same way with a trans cooler, it will still last a while, but you would be better off with it. JB

Limey wrote:if it is reverse rotation double check to see if it is not an Olds 307 first

it says on the valve cover sticker that its 305 cui. ive never heard of oldsmobile engines being rebadged to mercruisers, thought they were only chevy engines...

I see.......... but that would be the only explanation I would have for the reveresed rotation for the oldsmobiles do that. Do you have a pic of motor ??

The only thing reverse rotation about an olds is the distributor. The engine itself rotates the same direction as any other automotive engine.

now i know on my next statement ill end up kicking off a big debate but the 200r4 is an easier install and can handle decent power stock and with rebuild with a kit from art carr (not the shop that still carries his name) cand hadle well over 400hp. as far as gears seems like most people ive seen run no more then 3.55

gonna be 4.56 here sam with a full spool

but your n ot running 700r4 right and not designed for cruise friendly either

i do have a few pictures of the motor and will post them during the weekend. but im pretty sure that its a chevy motor because its completely the same to ones i saw in the books i have been reading and the one thats in my car now. some marine engines have reverse rotation because it helps the boat keep its direction if two engines are installed.

about 200r4, i know they are easier to install and quite durable, but there are two reasons i picked this one:
- its not that easy to find us car parts in slovenia, so i had to take whatever came up
- i only paid about $550 for it, and its completely rebuilt. the guy bought it for around $1200 before finding out that he needs an electronic version. you see, as hard as it is to buy us car parts over here, its even harder to sell them. his loss my gain.

as far as i know, the crossmember will have to be moved back into already drilled holes and the driveshaft will have to be shortened. i have a friend that is an experienced welder so this shouldnt be a problem.

i see you do recommend the oil cooler then. how about the lockup converter kit? how hard is it to install one of those?

and where can i buy new gears for the rear end? i was thinking that around 3.08:1 would be enough for now... but i have no practical experience with that so i wouldnt know

abajc3 - The Kickdown cable on a 700 is actually referred to as a TV cable, and it is of the UTMOST importance when installing a 700. If you do not have it adjusted correctly, you can burn up your transmission before leaving your neighborhood streets.

Here is a link to TCI's website on the matter.
http://www.tciauto.com/Products/Instructions/instructions/gm_tv_cable_adjust.htm

There are a couple different TV cable systems out there that make them very simple to adjust. I would highly recommend getting one of them. I personally have one from Bowtie Overdrives that works very well.

http://www.tvmadeez.com/


As far as the crossmember goes, you will definitely have to move it back and shorten the driveshaft. However, the pre-drilled holes in the frame won't work for you. You'll have to drill four new ones. Not really a big deal, but thought you should know.

Mercruiser used Chevy small & big block engines, as well as Fords in some years. Seems like it was the low bidder for supplying engines. They also used the 4.3 V6 Chevy engine. A good cam for that low compression 305 engine is a Comp Cams HE252, which I've used in the 305. I also put one in a friend's Mercruiser 305 on his boat, so he could get skiers up on the water easier. The in-expensive Magnum rocker arms from Comp are available in 1.6 ratio also, to help that small valve engine breath a bit better.

If you have no experience (or the right tools) you may want a gear change done by a pro.
At least you have a 8.5" rear, which will hold up to a lot of power, except maybe a built big block.

drilling new holes is not a problem, but its goot to know what has to be done so i can keep track of things during instalation. i will also read a book or two about th700 before installing it.

pila, that info about the cam and rockers will sure help, thanks! im also planning on gasket matching the heads and polishing them, maybe even smoothering the inside of the combustion chambers a bit (i know that polishing the chambers is only used for really high performance engines, but smoothering the casting remains is supposed to help. i will maybe polish the crank too, but i think that it is already better finished than the one from automotive engines.

i suspect that one of the main bearings might be spun, because the crank wont move. i removed everything else from the block so nothing else is stuck and from what i checked it doesnt interfere with the engine stand on the back.

i dont have any experience with the rear ends (actually almost everything i do on this car is a first for me, im 19 and i still have a lot to learn, but im picking it up quite fast). is there any good websites that describe this procedure, so i could see what needs to be done?

and thanks to you all for your advice, it really means a lot to me because there are very few people i can turn to with a question about my car over here. i hope that my english is clear enough for you to understand and i apologise for any mistakes i make

abajc3, we do not pay attention to language here. We know that this site can entertain visitors/members from all over the world. Not only that, but the English language varies so much from region to region in the USA that we pay no attention to it. JB

Don't get too involved in the combustion chambers. Every bit you grind or polish off reduces the compression ratio. Intake ports work best with a semi-rough surface to help keep the mixture in suspension, and not clinging to a polished surface. Exhaust ports benefit most from porting and polishing.

the max a 305 can be bored is .060 for 315 cubic inches yukon gears or radies ring and pinion or even richmond gears are the ones that pop into mind. and sorry i didnt realize your location

correct me if im wrong guys but the crome buckets on 76-77 montes work on same years of malibus. i know off topic

i know that messing with combustion chambers reduces compression, but there are some nasty casting remains in there and i think there would be some benefit from removing them. please correct me if im wrong, because i have very little practical experience with this and thats why your advice means so much to me.

i dont want to bore the engine just yet, because its almost new (300hrs, which is by my calculations about 5000miles) and boring it would be a waste of good block. i dont want to go all out on this engine and invest too mush money into it, because its just a practice engine for me and also my favorite toy:) i figure that i should get around 300hp out of it, maybe a little less, anything else would be too expensive. im planing on building a 383 or maybe even a 454 one day, so i have to save some money for then

If you have any metal flashing in there it will create problems, especuially in a modified engine. On a stock engine it matters not as much to a point. On the other hand, as long as you do not go overboard it wont hurt. Moderation has its advantages. JB

300 hp out of a stock 305 is kinda asking alot with out the new aluminum 305 heads and a good cam and bump in compression

What? Get some 416 head castings, around 220 duration cam, an aluminum dual plane intake, & you should be good to go. Since you disassembled the motor anyways, might as well step up the compression. I could possibly see close to 300 streetable hp without aluminum heads.

Regarding the 700r4,
Having done the swap myself just last year, hopefully I can be of some help.

There's nothing too out of the ordinary about swapping. You'll probably have to chop your driveshaft down by 3 inches and move your crossmember back slightly, but other than that is goes in smoothly. You will almost certainly need an adapter for your speedometer since the gears that turn it are different. When I first installed mine I had to skip that part since one was not immediately available and my speedometer was extremely inaccurate especially at higher speeds.

Finally, as mentioned the TV cable adjustment is critical but fortunately very easy to do. All you need to do is make sure the cable comes out all the way at full throttle. The TV cable will have a piece to tighten down so that you can pull your carb throttle back, pull the TV cable all the way out until you can't pull anymore, then sit that piece on the cable right up against the throttle arm so it can't slip back into the sheath. That'll pull the cable out all the way at full throttle every time. I recommend reading up more on the process.

Also, make SURE your overdrive lock-up works. If it does not lock-up, your transmission will shift between drive and overdrive way too often and burn out the clutch packs. You can have an elaborate wiring set-up so that this happens automatically based on vacuum in "drive" then shifts back down again if you press the brakes if you want. As for me, I just went with a toggle switch.

EDIT: And I might add, this is worth your time so don't think you can skip it. Importance to your clutches aside, the lock-up personally lets me cruise at under 1,500 RPMs on the highway. I love it. I flip the switch and I can practically feel the gas mileage soaring. Very good money saver.

There is a big difference between an 82-86 R4 and an 87-up R4. Make sure you find out what you have, there should be an easy to locate code on the case for you to look up. Aside from having different input spline counts (only relevant to your torque converter) there are a lot of structural improvements on the newer ones that make it the much stronger choice. Parts can also be retrofitted, and as grossly overstated as the transmission's weakness can be, it can also be built to withstand over 600HP with today's aftermarket rebuild kits. This isn't the 90s, don't put too much into anyone telling you it's a weak transmission. For your HP, a stock 87 or up should handle it just fine as long as you don't thrash it too much.

Oil coolers are ALWAYS a good idea but not necessary. Ditto with a deeper oil pan on it. A cooler transmission is a happy transmission. Heat and low pressure are the biggest things that will wear out your transmission.

Finally some personal bias to this post: ThrottleValve (sorry) bodies are available for the 700r4 which can turn it into a clutchless manual or even that but with the ability to retain full-auto in 'drive' giving it the best of all worlds in performance and comfort. If you take care of the 700r4, the ONLY downside if you are not running a monster motor with extreme torque and HP will be a little bit higher price tag and 100 extra pounds. You also can't dump a clutch manually. A very fair trade, IMO. I'll keep my auto.

Also, again this isn't the 90s. Small block GMs can put out more HP than you can use but it won't be as cheap as simply dumping in a big block. However, the small block is lighter and will not restrict the uses of your car to simply a straight line.

My two cents. Good luck man.

thanks for all the info, it really helps. i will definitely have to read a lot about th700 before i install it.

what mods do you recommend for the engine besides headwork, carb, intake, headers, cam, rocker arms, msd distributor...

I think you covered the basics if you're trying to just keep the cost down for now with a rebuild project in the future. It's more about how you apply those modifications.

With the 700r4 as your transmission, you really have no reason to go with part that build power under 1500 RPM since your torque converter probably has a stall at just a little bit over that anyways. Since you're dealing with a fairly mild 305, I don't see a reason to go over that either.

If it were ME, the first things I would do would be to add an Edelbrock air gap intake, headers, and... maybe a carb in the 450 range for now. When you tear everything apart for the cam and head work, that would be a good time to port the intake up to the heads. For simplicity DIY sake, look into gasket matching. Personally I dremel the majority of the material and do the fine touches by hand. Research your angles, talk to a mechanic or two, and see if you can't learn how to scuff the inside to get the swirl for your fuel. That is, you want your gas to hit intentional scuffs just past the port match so it gets a swirl to it as it leads into the cylinders. The only exception would be if you're building a supercharged motor.

But the intake, headers, carb, and porting are "free" performance. You shouldn't notice much of a gas consumption increase with those things since you'll be driving at the same RPMs as before, but you'll get much more power per RPM than you did previously.

Again, just my opinion on the matter. Someone else will probably give you an alternative to look into.

abajc3 wrote:
i was also thinking of changing the rear end ratio, which do you think is the most appropriate? (car is used as a cruiser, but id still like it to be reasonably "fast")

Since the other topics have been answered, I figure I will take a whack at this one now.


Here's my thoughts on the subject. Look for something in the mid 3's like 3.31, 3.42, 3.55 if it's a daily driver. Since you plan to run the 700r4, a 3.73 gear would be a great gear too. Obviously if you just buy a complete rear from another G3, then your choices are going to be seriously limited so you might as well find someone with experience in setting up rear gears & buy a new gear set with some sort of limited slip unit.