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Budget Build


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I am going to start a resto project on my first car. My dad bought a 1984 Monte Carlo for me when I was a senior in highschool. It came with bucket seats, T-Tops, counsel shift. Right now it has a 305 and a tired TH350. This is where the budget build comes in.

I have a 350(4-bolt) out of a '74 3/4 truck. In an attempt to add some cheap HP I am considering taking the heads off the 305 and using them on the 350. I haven't taken the heads off yet or even looked at the casting numbers so I am not sure what I am working whith quite yet. Has anyone had any experience putting the heads off a 305 onto a 350? Any feedback?

Here again in order to try to go cheap, I am also considering going with the Q-jet I already have. Any feedback / suggestions / etc. on the Q-jet?

I am also considering using the TH350 but also considering trying to find a 700R4. Any opinions on building the TH350 vs. going with the 700R4?

Any other tips, tricks, hints, suggestions, experiences, or even snide remarks grin would be welcome.

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The heads on the 350 4 bolt main are probably 2.02 heads. You would not want to put 305 heads on that motor. The 305 heads are probably 1.94 which means they have a smaller intake valve. If you are putting on a 4 barrel card, you want the bigger valves. Plus that 350 engine would have used regular gas.

Trany, I am not sure on that. I always went with a turbo 350 or 400.

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The heads off the 350 are only 1.70's crazy. If they would have been 2.02 (or even 1.94's) I would have tried to re use those. I think by that time they were putting the low compression dogs in the trucks so they weren't looking to crank much out of them. It even had dished pistons sick.

I haven't look at the casting numbers or pulled the heads off the 305 yet so I don't know what size valves they have. The plan to go with those is because of the smaller combustion chamber. I won't mind if I have to run premium, it isn't going to be a daily driver.

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To start off, how wild or mild do you expect to get with the motor?

The 305 heads will fit but many if not most of the 305 heads are also only 1.72 valves. Often they are a bit lighter casting, so even if they do have the bigger valve, they are frequently prone to cracking. Hard to know the CCs or valve size without casting numbers, but if you can post them I can tell you. A decent set of 1.94 are more than adequate for street use, and will not yield that much less performance than 2.02 in most cases. Make sure whatever head you use has the proper holes in them for mounting your accessories, they are not all the same, and alternative mounting can get complicated and spendy. Knowing what I know now, I would buy a set of aftermarket heads and bolt them on, rather than doing the set I had and not saving that much money.

A properly built q-jet is actually a pretty decent carb for the street, and can be set up to perform well at minimal cost, and are a very simple rebuild. (I actually have one on my car right now)

A turbo 350 is a cheaper rebuild than a 700R4, but the 700 with overdrive works well for the street in that you can get away with a slightly lower rear end gear if you are changing that.

Building hot rod motors can get spendy really fast. Unless you are doing a full rebuild with pistons and rings, your least expensive gains in performance will be in a camshaft, and bolt ons like heads, headers and a good intake manifold.

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Not too mild and not too wild. I am thinking 300 hp would be just fine. I want something that will sound good, get up and move a little but I am not looking at trying to turn 12's in the 1/4 mile. I want it to be a driver once I am done.

I have been looking at other sources of info on the topic and there is quite a bit of feedback on the subject.

Aftermarkets would definitely be nice but even the cast iron heads I have looked at online go for $350 each bare. I'd love to go aluminum but that is even more $$. I guess I could see what these heads are and compare what it would cost to get these in shape vs. what it would cost to get aftermarkets... I'll keep thinking about that one.

You brought up another good reason I was considering using the heads off the 305. They came with the car and the accessories will mount right back where they were.

Everything is at my parents house right now. I am planning on picking the 350 up soon and possibly pulling the 305 out of the car shortly after. I will definitely get the casting numbers as soon as I can.

It is going to be a full rebuild. The 350 is all ready torn down to the bare block. The camshaft will definitely be replaced. I am thinking about going with roller lifters. The manifold will be another item replaced along with adding headers. The Q-jet is still up in the air.

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As my budget build moves along like a herd of turtles. I have a crank that is a bit rusty but the price on it was right... free. Is it something that can be salvaged or do I need to look for a different one. If it is salvageable do I do something with it myself and if so what? Or do I as a machine shop to do something when I have it reground/cleaned up?

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Interesting thread.

Did you make a choice on the trans and the carb yet?

I had an 84 Trans Am back in the late 90's and that was probably one of my favorite cars that I have owned. If you are still in the process of doing things have you ever considered looking for a Camaro of the same year that was wrecked to see if you could get it cheap and use the 305/700r out of it? The Camaro should have had Tuned Port Injection and that would be a nice option for a street car over the carb IMHO.

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I'd take the crank to a machine shop. After they grind they'll let you know how much they took off and what size rod cap and main bearings you'll need to get.

If it were me I'd go 700r4 trans over the TH350 all day long. Lots of rods have them and the overdrive is a good money saver. During the install make sure the TVC is adjusted properly or the tranny won't last very long.

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I haven't made a decision on the tranny or carb yet.

I was leaning towards the TH350 because I already have it but that is far enough down the road I could change my mind on it.

Carb, I haven't totally decided yet. The TPI is an interesting idea I hadn't thought of... I wonder what type of investment and work that would be beyond just getting it (How much work to run the wiring harness? What kind of chip or prgrammer to get it tuned with current motor configuration? Etc?). You got me thinking though...

Will the machine shope be able to clean up the rust on the crank? It is just surface rust but it is all over.

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I am not sure what the market is for the Camaro's of that vintage (or even Trans Am's) but maybe look at trying to find a complete engine and Trans. Possibly in a wrecked car that you could do a complete swap of. Engine and Trans. One thing to consider on budget rebuilds that you may want to consider that I used to do when I was restoring old Chevelles and GTO's was to build a network of guys that have knowledge of similar cars and parts. I would buy a non running car for cheap from somebodies back yard and use the parts I could to upgrade mine and then strip the car and sell the parts for cash to fund other parts or to barter for something else.

There is also a market for your motor and Trans so for instance if you found a complete TPI motor and 700r Trans you could swap them in and sell your motor and Trans to another guy needing them for his resto.

Just a few things to think bout but if you aren't in a rush you can upgrade stuff and do it without spending much money.

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There's a lot going on here....

The questions nobody has asked are:

What's the budget?

What's your timing?

There is some pride in piecemealing it all yourself, but you might be better (and cheaper) in the long run with a crate engine of some sort.

http://www.summitracing.com/parts/MLL-BP3832CT1/

One thing to consider is the rear axle ratio cars from that era were typically pretty high gears which means pretty doggy performance. And, they're not particularly friendly to cams aimed at increasing midrange and high end power.

I had an '82 Monte that I put a mild 350 in.

Bored 30-over, Comp Cams 268, flat top pistons, 1.94 heads with 3-angle valve job, valve guides re-done, spring heights/pressure set, Edelbrock Performer intake, true dual exhaust with headers, Holley 600 CFM vacuum secondary carb, a re-curved HEI distributor. TH350 trans, rebuilt with a shift kit, trans cooler, and had the radiator re=cored with the biggest one the rad shop could fit in. Got second gear scratch on a good day.

Ran good, but the car had a 2.41 rear axle so while top end was decent, the low end never really lived up to the potential of that setup. Oh, by the way, blew a couple of those dinky rear ends with that combo.

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I am trying to stay under $1000.

Timing... well... this is the car may dad bought me when I was a senior in high school... I am now 35 grin It isn't a real big rush.

It isn't just about the end product, it is also something to do in the garage. It is a little cast iron therapy grin.

I am kind of expecting this to be a continual project. First, motor and tranny. Then probably body resto. Then ??? Maybe suspension... Maybe... ???

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$1000 is pretty tight.

You may be able to get all the necessary bits like headers, intake, exhaust system, re-ring kit, oil pump, timing set, and cam & lifters, then all the miscellaneous tidbits that you come across for that amount, if you really bargain shop.

However, that assumes no machine work is necessary to the crank, block, and heads, which is a risky assumption. At the very least you're still going to need to (or should) get the block tanked/cleaned and pressure checked, heads cleaned & checked for warp, valve job, etc.

Having run a similar car, I do advise that you seriously consider ensuring the rear end ratio is straightened out as one of the first things you do. Getting that rear end into the 3.xx range helps quite a lot in the "pep" department. 3.23, 3.42, or maybe even 3.73 since it's not a daily driver. I know the rear end isn't a fun, glamour part for everyone to see, but trust me on this...you want to get that ratio down (higher number) from stock.

For a cam in this type of setup, something with intake duration (@ 0.050") in the low 200s. A 204/214 with around 0.430 - 0.450 lift is a nice cam for low/midrange torque, probably peaking HP around 4500-5000 RPM. 5K is probably about as high as you'd want to go anyway assuming you're not going to put any money into a good valve train and heads.

Pair that cam with some small tube headers, dual exhaust, Performer intake, ~9:1 compression, and rear end of 3.23 or 3.42 and you'd have a decent rig. Wouldn't be a race car, but it'd be a snappy driver.

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Yeah... like I said trying, but as I get further into it I am realizing I will more than likely be going well above that number but it was an attempt to keep the cost reasonable and the motor fairly tame grin

I was thinking 3.42 at the lowest for gears because I want this to be a bit of a driving / touring car... but ??? 3.73's would be pretty snappy

... I know the rear end isn't a fun, glamour part for everyone to see, ...

Unless you're J.Lo blushlaugh (Sorry, couldn't resist)

I have 58cc chamber heads so the comp. ratio will probably be pretty decent. Cams... I had a few in mind 206/212 with .425/.440 or 210/210 with .440/.440 or 214/224 with .442/.465 or 216/216 with .454/.454, although that last one or two might be getting a little lopey. You are right, I am not planning on going to wild with the valve train and I am going with a dual plane intake, no stall converter... so the cam wouldn't be any more than what I have listed.

Probably one of the bigger factors of keeping it pretty mellow is drivability. Once the motor is in the car, set up and broke in I don't want to have to fiddle with it much. Turn the key and go.

Thanks to everyone for the input and if there are anymore good suggestions, keep 'em coming.

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58cc heads on a 350 with standard flat top pistons will, I think, push the compression ratio higher than you want.

The Comp Cams HE268 I had in mine was 218/218 @ .454 and it was too much for the stock gears. I stepped back to the 204/214 and it worked out better overall in that setup.

Cams are an interesting topic. Almost always people tend to err on the size of too big, just in case, then wonder why it's soggy. As did I, even against similar advice smile and found out they were right.

Also, a HEI distributor is a good setup with an aftermarket module. If I can find it I'll show you a trick about modifying it to allow full advance. Even with an aftermarket recurve kit the shape of the flyweight cam in the distributor can limit the advance. So, to try to get up to the typical ~36deg, total mechanical timing (initial + advance) requires lots of initial advance which isn't necessarily a good thing in conjunction with the vacuum advance. With the mod you can cut back the initial timing and get it back for the higher RPMs in the advance curve.

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58cc heads on a 350 with standard flat top pistons will, I think, push the compression ratio higher than you want. ...

I was thinking it wouldn't be too terrible with flat tops, 10.75:1, assuming a .04" gasket thickness and .035" deck height. I was also considering going with a 11 cc dished piston which would bring it down to about 9.5:1. I was planning on running premium either way.

There's good info out there on cams. Like I said, I am staying fairly tame so I appreciate the advice.

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If you are looking at getting a complete rebuild kit, check out Northern Automotive. I have used their kits on two different motors in the past and they have held up well.

I built a .30 over 350 using their kit with flat tops, cast 76cc heads, performer intake, and comp 268h cam. This was put in a 83 firebird along with a turbo 350 trans and 373 gears. I wouldn't recommend the 373 if you are going to hit the freeway. At 65-70 I was pulling about 3000rpm.

Other then that it was a nice combo.

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I started out with the 700R4 and the 2... gears and once the trans died I found it cheaper at the time to swap out to the TH350. Later I swapped the rear end for one out of a trans am that had the 373 posi/rear disk set up. That's when I ran into the higher rpm issue.

A 700R4 with a shift kit would be a great way to go.

A simple solution would have been to run a taller tire but for the little bit of freeway travel I did with the car I didn't bother.

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10.75 is pretty high for cast iron heads with the gas we have today.

So what do you think? Stay under 10.5:1, 10:1,...?

The 700R4 is really starting to tweak my interest too. I was planning on going with the TH350 because I have it (which would make it a little cheaper) but if the 700R4 is going to make the car a better driver it may be something I seriously consider.

Thanks again everybody, this is all good stuff.

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So what do you think? Stay under 10.5:1, 10:1,...?

The 700R4 is really starting to tweak my interest too. I was planning on going with the TH350 because I have it (which would make it a little cheaper) but if the 700R4 is going to make the car a better driver it may be something I seriously consider.

Thanks again everybody, this is all good stuff.

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Probably 9.5 unless you're going to go aluminum heads or try some other trickery. Maybe unless you want to run it on E85 or a high alcohol blend, but then you burn a bunch more fuel too.

My '91 Z-28 is rated 9.3:1 (iron heads). I use 91 octane and if I watch the knock sensor on scan tool I can see it taking away some advance at times.

I know you can get 111 octane in St. Cloud at one of the fuel banks, but it's currently $8/gallon. frown I think it's leaded too so no O2 sensors or cats.

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