NowhereFast

My 305 had a leaky head gasket, so I decided pulling it out was easier than doing the gaskets in the car. Now I have it apart and on a stand, and I'm wondering what the next step is, or rather, what I should do.

Here's a shot of one of the cylinders, and one of the intake valley.



Not too bad.



Little sludgy. Surprising though, because the rest of the car was taken care of pretty well.

Seeing as the oil probably wasn't changed too often, I'm wondering if I should do main and rod bearings. Maybe even send it out to have it decked and bored .030 over, because I don't want to put it all together and find out the deck was warped, and the .015" head gaskets aren't sealing.

But if I'm going that far, would it be better to just build a 350 bottom end? I have a bare '87+ 350 4-bolt roller block just sitting around. I'd like the car to see high 12s or at least low 13s, but I want to stick with TPI.

sofakingdom

iTrader: (1)

Strip the roller apparatus out of it. Pull the heads. Trash everything else.

Yes it would be better to build a 350 than a 305. Not hard to do the math: same $$$$, 15% more results. Even I, as dumb as I am, can figure out that that's a deal where you only leave money on the table when you leave, if you TOUCH the 305. Match the pot & fold.

Tough to break very deep into the 13s, let alone 12s, with that crappy TPI on top of your motor, without a bunch of nitrous or something. Pipe dreams. Be realistic.

Tibo

iTrader: (15)

Since you are in New York and it's getting colder out make this your winter project. Use that 350 roller block. If it is a bare 350 roller block and you need to buy crank, rods and pistons just go ahead and build a 383. The 383 rotating assembly will not cost much more than the 350 assembly. High 12's with a 383 is not hard to do. Ditch the TPI in favor of the HSR for an easy bolt on install or the Pro Products single plane with an elbow if you don't mind extra set up work. Grab a set of used aftermarket heads and a used roller cam. Good Roller cams come up for sale here fairly often, I have a 280 XFI I will be selling soon. Alternatively you could put it together as a 350 with <9.3:1 CR and add an ebay turbo when money allows. Many members have done fine at lower power adder levels with the ebay turbo route.

NowhereFast

Trouble is, the 350 came out of my shop class, and it was bare when I got it. I'm sure the main caps were mixed and matched. Ive heard align boring is a pain in the neck when it comes to buying parts. Is it possible to determine if the caps are in the right place?

sofakingdom

iTrader: (1)

Of course:

Just move em around until they fit right.

There's only 4 of em.

Not exactly rocket science.

NowhereFast

I'm mechanically inclined and work at a shop, but I've never gone this far into a motor before.

You mentioned keeping the 081 heads. They would be a viable option on a 350/383? Compression would be sky high wouldn't it?

Night rider327

iTrader: (13)

Don't do anything to the 305 other than a head gasket change. If you are putting more money into or want more formance out of it, your just wasting time and money on the 305.

Straight edge / feeler gauge check the head and deck surfaces to see if they are flat. Put gaskets on it and toss it back into car and drive it until it has major issues.

Or if your wanting 12's out of the car, build your 350. I do not recommend a 383 build for your 1st time though due to having to grind the block's oil pan rails and bottom of cylinders.

Pull the 305's roller cam parts for your 350, of course do use the 305 cam in your 350 build.

Put your money into the 350, you will be much happier with the end results

sofakingdom

iTrader: (1)

You yourself may not have much use for the heads in your current situation, but someone else might.

A 305 short block, on the other hand... people can't even GIVE those away.

As far as the main caps, acoupla pointers:

The text cast into them all faces the same way; you won't have some facing one way and others the other. They should fit tightly into the register step. Attempt to install them GENTLY using the bolts; when the bolts are tight (a few ft-lbs is all that's necessary) there should be no more than .001" mismatch at the parting line in the bore, and the bore should measure the same in both directions. (i.e. it should be round, not oval) Once you find the first one, they get ALOT easier after that.

Tibo

iTrader: (15)

Almost any machine shop will clearance the block for a negligible amount if they are already doing work on the block. On a machine it takes longer to setup than to do the actual clearancing. It's a pretty simple operation even for a novice with hand tools. Put the crank and a rod in with some old bearings and slowly clearance it out to whatever is recommended (0.05-0.10?) Choose a rod with cap screws (ARP 8740 or so) and you don't have to clearance much. 383 will make 15% more power than a 355 for only a small amount more.

NowhereFast

What has to be ground down? I'm sure I could do it, or worst case have the machine shop do it.

I have to buy a rotating assembly anyway for my 350 block, so I may as well stroke it.

The main caps are in place, but I haven't looked at them to see if they're right or wrong.

Say they are wrong, which is the most likely scenario, would putting them on that way have damaged anything?

sofakingdom

iTrader: (1)

Probably not.

That will depend on the rods you use. Generally, cap-screw rods, as opposed to stock-like nut & bolt ones, will save you AHELLUVALOTTA grinding, since the top of the bolt, and the area right around it, is what hits things. Places you will encounter interference are the oil pan rails, the bottom of the cyliders, and the cam. Obviously you can't grind on the cam, gotta deal with that one some other way.



Which one do you think has the better chance of fitting?

NowhereFast

So cap-screw rods are definitely the way to go.

I guess I'll be building a 383 this winter. Obviously I'm new to this, so would you guys mind helping out along the way? I'll buy a book or something to supplement.

Suppose the first step would be taking the block to the machine shop and have them go through it. Hot tanked and checked for cracks. Zero decked? .030" overbore? Anything else?

Tibo

iTrader: (15)

Zero deck, Line hone the main journals, hot tank, new cam bearings, 0.030" overbore, Check the block for cracks. Then ask how much they would charge to clearance the block, ya know, since they are already doing a bit of work for you. Because you are "just curious" if it would be better for you to just do it. They would probably cut you a deal then, that is if you were still timid about doing it.

Something like this ( ) should be helpful. Yes all of that information can be found online with more detail and better pics but this is all in one place and requires no searching or internet connection.

If you get cap screw rods you most likely will not need to worry about any street cam you would run. Cams can be ground on a small base circle but then they will require longer pushrods and/or different lifters.

MoJoe

iTrader: (5)

Don't cut more than is NEEDED to get the deck flat or bores round. This allows the block to be rebuildable in the future.

Deck height: From the crank centerline the the head surface of the block, stock is 9.025". The stock stack is 1/2 of the 3.48" stroke (1.740") + the 5.7" rod (7.44" so far) + 1.560" piston compression height = 9.000". So, a stock 350 has the piston 0.025" in the hole.

383 - the cranks is 3.750". 1/2 of that is 1.875".
rods - available in 5.700" or 6.000".
pistons - that leaves1.425" (w/ 5.700" rods) or 1.125" (w/ 6.000" rods) compression height* to get the 9.000" stack.
*compression height = pins bore axis to face of piston.

Looking at Summit, pistons are available for 4.030" bore in 1.425" (9.000", 1.430" (9.005"), 1.433" (9.008") for the 5.700" rod and the same increments for the 6.000" rods... 1.125", 1.130", and 1.133" for a total stack of 9/9.005/9.008.

Bores: Stock is 4.000". Rebuild pistons should be available in 0.010" increments, with 0.030" being popular. I haven't looked closely at available pistons in 20 years, so do your homework. Next, have the machine shop see what it will take to clean up.

Q: Why is the deck height and stack height important? A: to determine your compression ratio. Answer us:
- Intended purpose? daily driver, street, drag.
- Do you want good gas mileage? That means a milder cam and a lower SCR.
- Are you chasing max power? That means a longer duration cam and a higher SCR.
- what heads are you going with? Chamber size?

One will assuming you are getting heads to support your desired power level. IE iron L98 heads will not support 400hp.
For the power level, you determine the cam duration. Then target 7.5-8.5 for your Dynamics Compression Ratio (DCR), factor in the cam to determine the Static CR (SCR), which you juggle head CC, piston dish or dome and head gasket thickness to achieve.
Although ideal quench (piston-to-head clearance) of 0.035" to 0.050" limits your adjustment head gasket adjustment.

NowhereFast

It's funny you mention that, I ordered it right after I last posted in the thread. I would like to know how it all goes together and why it matters, rather than just throwing together parts from a list.

Thanks for that, now I can kinda picture how all all the measurements come together. Basically, the end game is to get the piston to be dead even with the deck at TDC? Or in other words, stack should be equal to deck height?
1: The car will be almost purely street, being that there are no tracks on Long Island. I'm going for a pro-touring kind of deal.

2: Gas mileage isn't super important, but I want the car to be somewhat docile while still making a good amount of power, and I know the cubes of the 383 will help with that (again, pro-touring).

3: I don't know about max power, just something that will push the car to low 13s or better.

4:I know nothing about heads. I don't know what numbers like "175cc" mean, but I know chamber size affects compression, and you pretty much want them to flow as much air as possible. Was hoping I could get some suggestions on a decent head to use.

MoJoe

iTrader: (5)

Zero deck should not necessarily be a goal, but it can work just as well as anything. For instance, 0.025" in the hole + 0.015" head gasket = 0.040" quench. 0.015" + 0.026 gasket = 0.041", 0"+0.045" gasket = 0.045". So, there's plenty of combinations to get to the quench target.
That's why you see what it takes to clean up the block, whether 10,15,25 thousandths of the deck, and 30,40,60 thou on the bore. THEN you order pistons, for the bore. Playing with head gasket determines if you need something other than the "standard" 9.000" stack.

Here's a background on Quench, and why I am harping on it: this is the piston-to-head clearance, and is the flat part of the head over the piston, that is not the valve/chamber. I think it was David Vizard who got this as low as 0.026" before the piston hits the head due to heat expansion, rod stretch, etc. 0.040" is the optimum figure I've landed on... as small as practical without worrying about contact. When the piston compresses the gas+air, the mixtures gets squeezed out of the quench area, squirting toward the sparkplug. This give the mixture motion and better turbulence to help combustion happen faster. This leads to less timing (less combustion pressing down on the piston while still traveling UP), and more complete combustion which means less emissions and more power.
You can read more on this thread, with picture on post #13.

Next start plugging numbers into a compression calculator:
4.030 = bore
3.75 = stroke
75cc head chamber size (this is one major detail for heads)
5cc dish or -xxcc for a dome. This will be an advertised number for pistons.
0.015" deck clearance
0.026" head gasket thickness (again desk + gasket can be adjusted)
= displacement = 383ci
= compression = 9.84:1
FYI: change the head from 75cc to 65cc and CR goes to 10.96:1... probably TOO high. Then change piston from 5cc dish to 12cc dish and it drops back to 10.16:1... which is more pump gas friendly.

I am building 9.8:1-ish on an iron Vortec headed 350. If you get aluminum heads, you could go another 0.5:1 higher and still run pump gas.

Using some of the SoCal member's accomplishments, a cam with timing at 230* @ 0.050", with advertised duration in the 280* area will make really good power, and still pass emissions, which I take as an indicator of fairly smooth idle or "docile". This cam timing also brings the 9.8-ish SCR down to 8-ish DCR, for use with pump gas.

Two major numbers on heads are
1) the combustion chamber size to get a good CR:
1a) 58cc is typical on a 305.
1b) 64cc-65cc is typical on a 350.
1c) 65-75cc for a 383, as mentioned above, play with pistons to get low, medium or high CR.
2) intake runner volume. Too small and you get good low rpm velocity, but choke off high rpm hp. Too big, and you don't get low rpm benefit, and if you don't need the extra size, you will never get the high rpm benefit of all that flow.
2a) 175cc is a very good torque port, and is probably matched to the rpm limits of a TPI intake.
2b) 195cc is a better choice. Not too big, yet will still flow enough to feed a 383 at 6000+ rpm.
2c) 220cc is a big engine race head. If you are building a 400+ci engine and/or turning it to 8000rpm, then you can use this.
The Air Flow Research 195cc head is very popular because it is high quality, makes great power, and is reasonably priced. That would have been my choice if I was playing with a larger budget. (Complete L31 Vortec 350 with head machine work for $2500 vs spending $1500 on just heads)

NowhereFast

I was hasty and bought a Crane 2032 cam when I thought I was just gonna re-gasket the 305. Could it be used in a 383 with 1.6 rockers, or would it be too small? I want something that will work with TPI and minimal computer tuning until I can get a better intake and learn how to program.

Tibo

iTrader: (15)

That will require tuning to run well.

MoJoe

iTrader: (5)

"Too small" means you could have more power. Too big, and you probably won't enjoy the car/engine. Here is a thread discussing that cam. The 383 can handle a bigger cam, but between 305->383 and a bigger than stock cam, you WILL have a power increase.

It is a lot more lift and duration than a stock TPI or LT1 cam. Here is a comparison between the 2032, LT4 HOT, and Comp502 cams.

Crane 2032 LT4 HOT Comp 502(XR269)
lobe lift .301/.310
lift w/ 1.5 .452/.465 .492/.492 .495/.503
lift w/ 1.6 .481/.496 .525/.525 .528/.536
@.050 214/220 218/228 218/224
duration 270/276 279/287 269/276

LT4 - popular and a bit cheaper than the Comp502.
Comp502 - With 10* less advertised duration than the LT4, but the same or less duration at 0.050, the 502 is a 'more modern" grind and has steeper ramps. More power, smoother idle, but NEEDS better springs.

NowhereFast

My good friend just offered me a 383 for free. 4-bolt main, but it's an earlier block, 2-piece RMS and not set up for a roller valve-train. It's been sitting for the better part of 14 years.

Should I take it and run with it? It'd be a lot cheaper than building my block from scratch, the 383 only needs a set of heads because he messed up a DIY porting job. Will all the sensors for a TPI bolt into the older block? He also offered me a never used cam and lifter set from about 12 years ago. Old Crane grind. Would I be better served getting a roller conversion for the motor? Here's the card on it.

MoJoe

iTrader: (5)

My take is go with a roller cam. Period. You will always get more power and smoother idle with a roller than a comparably spec'd flat tappet cam. Modern oil blends do not have ZDDP additive, so there is a higher chance of the flat tappet cam and lifter eating each other, which means you end up replacing the cam. What is the cost of aftermarket roller cam, lifters, thrust plate, & button?

You're not making enough power for 4-bolt to be necessary.
2-piece RMS only affects your choice of flexplate or flywheel (expensive after market, if you end up looking at a T56).

Sorry, back to you to do the math on what you can afford, and are able to do.

FRMULA88

Not to discourage you from learning or DIY.. BUT there is nothing special about a 383 that you need to have a shop build one from your stock motor for street 'pro-touring' use.

In the long run you will save a lot of time and spend less money and yield similar results buying a crate engine 383.

If you were building a max effort race engine by all means a machine shop is the way to go since you will be a repeat customer for the shop.

FRMULA88

http://www.summitracing.com/search?S...crate%20engine

Night rider327

iTrader: (13)

Yes you should take the free engine and run with it. Even if it's not what you want parts wise, it's a good base to start with, and it's free.

Budget comes into play on flat tappet vs. roller cam... Yes a roller cam is better. No question about that, but a retro fit roller setup is around $700-900.

I would much rather have great heads and a flat tappet cam, than a roller cam and ok heads. The better heads will make more power than the roller cam would.

If you have the budget for both, good heads and roller cam then by all means go that route.

Lurbie

iTrader: (3)

I totally agree! Hindsight's 20/20 as they say. If I had to do it over, I'd buy a crate engine. In my case I could have saved over $2k for other mods and had my car on the road 2 yrs quicker. Start pricing out everything and you'll realize that unless you're just all DIY or doing a goal-specific build like racing, a crate engine is way better choice.

Tibo

iTrader: (15)

Whether or not purchasing that short block for $2,000 would be debatable. Some machine shops are really inexpensive while others charge an arm and a leg. If you have no time constraint and can be attentive to detail, building an engine isn't very difficult. You can purchase a name brand rotating assembly balanced for under a grand. So it is just in how much a machine shop charges. If you have a competent and experienced friend to help you the argument for building it yourself is even better.

FRMULA88

Shops service racers (repeat customers) first.

Go to any shop with a "no time constraint, pay as I go attitude " and see what that gets you. It gets' you to the end of the line waiting 1-3 years OR MORE for a motor VS buying it out of a catalog and having it drop shipped to you 1-2 weeks.

Not to mention the crate motor will come with a warranty, a shop built one, not so much.

I think for what OP wants to he should save his money call Summit or Jegs and pull the trigger.

Night rider327

iTrader: (13)

I don't agree with the above. I do know that happens, but I build engines for a living and I never put the avg. guy in a line and cause him to wait that long.

Yes you keep your repeat customers happy, but you can't get repeat customers if you treat new customers as second rate customers.

I build them in order that they come in and I tell my customers how many I have ahead of them and give them an estimated build time for theirs. If i'm more than 2 weeks past the written est. date then I make it right to them in some way or other. Be it free upgrade of X parts, or knock X % off the total price.

Lurbie

iTrader: (3)

I think that's the problem, we ALL know there are really good engine builders out there. I am very analytical and do a lot of research before I pull the trigger on anything. Unfortunately, I am also one of the ones that got things I didn't ask for and didn't get things I did. I won't slam the machine shop I went to because they had family and medical hardships at the time. It was my fault for leaving it there having known that, it was my fault for not forcing them to correct the incorrect parts, it was my fault for not forcing them to fix the poorly clearanced block. Granted I took care of what needed to be taken care of to make my engine work, but I put almost 2k down just on a rotating assembly and basic 383 block work to find out after the place shut down that I didn't get what I paid for. Doing a slow build was also part of it taking so long to notice all the things I didn't get that I believe I paid for. I've since put another 3k into it over the last 3 years. Like I said, hindsights' 20/20, having known then what I know now, I would've bought a crate engine. Nothing against the good engine builders out there, but they're extremely hard to find. In my case, it seemed that whenever I thought I found a good place the person that made it good had moved on to something or somewhere else.

NowhereFast

Decided to use the 383. Gonna have it sent out and gone over.

I'm gonna convert it to a roller set up. Anyone have any recommendations on a good set of heads and cam, other than the $1500 AFRs?

I've heard great things about the XFI268, looks like it will be just right for a mild 383.

Might throw a stealth ram on in the future if the TPI doesn't do it for me.

Tibo

iTrader: (15)

That cam in the 383 will idle almost like stock. XFI280 is a much better choice, I ran it and switched to a slightly better cam. I have the XFI 280 i am selling now.

Any used aftermarket name brand aluminum heads will do you fine.

NowhereFast

Any difference between the XFI268 and 280 other than duration? Comp's site says the 268 is for retro-fit roller, like I'm doing, and the 280 is for OE roller motors.

Night rider327

iTrader: (13)

Stock vortec heads are good budget heads

Aftermarket for cheaper but good heads all are gonna be in the $1,000-1300 range
Jegs brand alum heads
Pro filer
Summit brand alum heads
Brodix IK

For a 383, other than the vortec heads I would look at 180-195cc intake port heads

LB9GTA

iTrader: (1)

That's what I had in my previous 383.
280xfi, flat tappet
Afr195
Flat tops
With a lt1 converted intake

Ran a best of 12.09@110

I wouldn't waste the money on a roller setup. With everything it'll cost well over $700

Night rider327

iTrader: (13)

Put your money into the best heads you can buy rather than a roller cam swap, then if you have the funds to do a roller cam retro fit, do it.

You will make more power and get the most from your money out of the heads.

A roller cam vs. a flat tappet of the same size will gain you 20-25 HP or so.

Where a much better head can gain you 75 HP easy

NowhereFast

...

NowhereFast

Went to a machine shop today. The dude gave me a ballpark figure of about $3000+/- to take my bare block, machine it, and put in an all forged stroker assembly.

I figure it may just be quicker and easier to use a ZZ350 short block, and put the heads and cam I want on it.

How much of a difference am I looking at in the power each would put down? Whichever motor I go with, it'll get AFR 195s and a 268XFI cam, with about 10:1 compression.

Looks like ATK makes 2 383 short blocks, 1 for around 2000, and the other around 3000 with a forged rotating assembly. Just haven't heard much about them, but if they are any good, it might be worth it.

FRMULA88

3000$ to prep the block install & install new crank, rods, pistons & rings ?

What about the rest of the short block assembly ? ( timing chain, cam, oil pan, oil pump.)

see what I mean?

for 2,000 $ you can buy a complete short block 383 from Summit

and for less than 6,000$ the complete engine.

LB9GTA

iTrader: (1)

From Skip White
http://www.skipwhiteperformance.com/...?Item=406SBKFT

406 unassembled shortblock for $2800

Lurbie

iTrader: (3)

Wow!! That's a nice setup for that price. Dart SHP block, Scat rotating assembly, if you want to do it yourself, that'd be a nice starting point.

Tibo

iTrader: (15)

That crank isn't made to handle more than 500 horsepower. Sure it probably can but for how long and how much horsepower?

2005Impalla

I would just run a set of vortecs with some comp cams beehive springs and a coms cams Xtreme 268 cam.

2005Impalla

$3000 for a 383 short block is way to much. You need to find a new shop. You don't need forged internals if your just looking to hit low 13s. I ordered my new vortec 350 long block for $1997 shipped to my front door from Jegs. Its not a 383 but it has vortec heads, 9.4 compression, strong connecting rods and pistons, 1 piece rear seal and factory roller cam.

rusty vango

square up the block. or in other words "blueprint" it. looks as if you may have bore issues too. time for a overbore and some hypereutectic flat tops on a set of "H" beam rods. I would also spring for a scat forged crank too and balance the whole rotating assy. but , hey that's just me.

Tibo

iTrader: (15)

So you are advising this member to drop some major coin on his 305 engine?

VincentZ28

iTrader: (2)

Wanna run 12's on a budget? Strip the 305 block including the crank. Get all the bolts and screws from the 305. Reused the rear main seal holder. Have the crank balance with stock 350 powder metal rods. Buy some flat top pistion. Get new roller lifters and a little bit above stock cam. Put the stock TPI back on with 22lbs injectors. But a set of Dyno Don headers with a 3in cat-back Magnaflow exhaust system. This simple will get you into the low 13's or hi 12's at 105-110mph in the 1/4mi. This is thinking on a budget.

Oh by the way, 305 and 350 has the same crank with the same stroke. The 305 crank is machined lighter to accommodate the lighter 305 rod and pistion.

InfernalVortex

iTrader: (4)

Going roller cam is the best move you can make. I'd rather have a roller 305 than a flat tappet 350 at this point if I were building a new engine. Going roller in a flat tappet block is a huge waste of money, though. Roller blocks cost less than the conversion hardware.

2005Impalla

I know you want to re use your TPI but I would sell it and use the money to get a new carb set up. Its great in stock form but will not allow the higher RPM power your looking for to hit the ET you want with out replacing most of your intake and re tuning. The stock intake runners are too small unless you super charge. I would at least swap to a Holley stealth ram intake if your going to keep it TPI.