jvaughn

iTrader: (1)

Hey guys and gals,

Pretty new to this site and to the third gen world. I have found a lot of great info on here, and now feel that it is time for me to take a dive to the deep end of the pool. Now I am going to say right up front that I have never done anything close to this. I just got into cars in the last two years, but I love tearing things down and fixing them. I learn quick, but dnt know all the lingo, so be patient with me.

I am looking to change out my 89 305 TPI set up with a 350 and have some upgrade questions.

I picked up a 350 block casting #14093638, roller block, that has been bored .30 over and the crank is .10 under ($60.00). No heads, cam, or lifters in it (short block). Guy I got it from pulled it from his 76 Camaro he was restoring. Said he believes the motor has less than 60k on it. Here is some info I found on the pistons. Looks like they come from Flatlander Racing, and they are TRW pistons.

Specs:

Part #H631P-30
CID 355
Comp Ratio

58cc-10.41
60.5cc-10.11
64cc-9.73 -With the 906 heads this is where I should be.
68cc-9.33
72cc-8.97
76cc-8.63
Comp. Dist-1.560
Piston Shape-F/T

I wanted to build it up a bit but not sure where to go. I dont want a speed demon, just want to spin the tires, and maybe beat a couple of college kids off the red light.
Maybe 300-350 hp? I have a budget of 1k-1500.

Picked up a set of 906 vortecs that are in really good shape. Planning on porting them to them to the best of MY abilities. Think of doing 1.5 roller rockers with them, or just leaving the stock one in it. Im seeing that there really isnt a big difference in the two.

Looks like from what I am seeing the heads stock should take up to a .450 lift, so I am thinking about going with the Edelbrock 2103 cam. Duration 288/288, Lift .442/.442.

Now my current car has a 305 TPI in it, and I have purchased a complete 350 TBI, with wiring, harness, and ECM for 250.00. Im trying to decide if I want to get a better intake and use an adaptor plate for the TBI, trying to use the current TPI, or just carbing it.

A vortec intake for the TPI is crazy expensive, but I feel like I would get more performance from it. On the other hand the TBI setup looks like it can be just as good with the right combo. But I really am liking the simplicity of the carb.

Right now the car is pretty stock, except some cosmetic changes. It does have a posie, but Im pretty sure it has 2.73 gears. I am planning on changing them out, and adding better lower control arms, panhard bar, and frame supports to stiffn up the underbody.

Car has a stock 700r4 as well. Seems like the previous owner may have installed a stall converter, but not sure until I pull the 305.

So here is my parts list so far:

The block and pistons listed above
906 stock heads-that I am going to port alond with the intake
Edelbroc 2103 Duration 288/288, Lift .442/.442 Flat Hydro
Comp Cam 2100 Double Roller Timing chain
Headman Hedders 68460
Summit Racing intake and carb kit-Dual Plane 0-6000 Idle range Intake Manifold, 600 CFM Carburetor with electric choke, Air Cleaner, Fuel Line, Gaskets, Bolts

What do you think? Worth it? Am I going to reach that 300-350 hp range? Am I in over my head here? Please guide me old wise ones! LOL

Thug Life

if its a roller block then go with hydrualic roller cam I suggest LT4 hot cam tested it before and it was great on L98 aluminum heads but with vortecs and pistons you will get to 350hp easily

travis401

iTrader: (1)

those vortec heads flow great even without porting. if youve never tried porting anything before id suggest trying on some junk heads before diggin into the vortecs. over all not a bad set up, youll enjoy it. just take it easy on the stock auto and rear end

jvaughn

iTrader: (1)

Overall not bad? Is there something I should be changing? I know the stock rearend will need to be upgraded, but should the 700r4 stock take 320 hp? THis combo shouldnt go over that will it?

Thanks for the advice on porting, Ive got a set of swirl ports that came on another motor im going to practice on first, befor the vortecs. Dont want to mess them up.

jvaughn

iTrader: (1)

The LT4 cam would require me to change out the springs and such on the heads. Not sure I will have the cash right away for that. The lift is to high for the stock heads. And the roller cams are so expensive. 349.00 for the same duration w/o the roller lifts. Kind of a budget eater!

travis401

iTrader: (1)

the autos tend to hold up to more hp more readily than the t5s. as long as you arent too rough on it i think it should be fine. but i am no expert on the autos...

jvaughn

iTrader: (1)

Dont plan on taking it to the strip. Just intown driving and a few light to lights

Orr89RocZ

iTrader: (20)

leave the heads alone. If you dont know what your doing, you may mess them up since they are finicky heads to work with. They flow enough stock to make more hp than what you are trying to make.

I'd just take them to a machine shop, and get the deck resurfaced and have screw in studs installed so you can run a good cam and good springs.

I'd go with a slightly smaller cam than the edelbrock. If its a roller block, a hotcam would be a great budget cam. I'd use that and just have the heads setup to handle the lift. Its not that much of a cost to do so.

Carb is likely cheaper than vortec TPI and will make more power than either TPI or TBI. If you can, go edelbrock proflo XT for vortecs as I think they make those now, or Weiand/holley stealth ram for vortecs. About same cost as aftermarket TPI if not cheaper and works better.

Ozz1967

iTrader: (4)

The rear will easily handle up to 350hp, 350ft-lb of torque on street tires. After that, or if you run slicks or drag-radials it's a time-bomb.

The Vortec's are the best 350 heads chevy ever made (not counting the LS heads that came later). Edelbrock sells a good dual plane intake that will work with any setup you want. Just look up the performer and performer RPM.

For the carb...can't go wrong with the QuadraJet, though several people here will tell you otherwise. that's a never ending battle! haha

jvaughn

iTrader: (1)

I thought the rear end should hold up, but will change out eventually. So far what I have read about the Vortec's, seems like I'm heading in the right direction. Thanks for the comments, getting one heck of a education on this site!

jvaughn

iTrader: (1)

Dont really want to change out the springs and such right now, maybe down the road? Why a smaller cam? Too big? Isnt the hotcam bigger than that? I'm liking the carb idea better. Seems I can get more hp and it will be a easier setup than messn with all this ECM computer stuff. And the simplier the better at this point for me! LOL

86bumbleb

Duration at .050 in. 218/228, Lift .525/.525, LT4 Hot Cam Lift With 1.6 rockers
.492 with 1.5 rockers

86bumbleb

.492 lift with 1.5 rockers

jvaughn

iTrader: (1)

That is bigger than what I was planning on running. Not sure if I want to go that extrem on the first build. Benifits of this one rather than the one I was looking at?

Orr89RocZ

iTrader: (20)

Nevermind the cam you had is fine, and is quite mild. Hotcam is abit larger but not radical and if you go carb it will be easy to tune. Is that edelbrock cam a flat tappet? if you have a roller block I'd stick with roller cam since they require no break in time and work well with todays modern oils that have less zinc and phosphates that are required with flat tappets. Hotcam you would need to swap springs/have heads worked to handle lift. The edelbrock cam should drop in and use stock replacement type springs. Its a mild cam not much bigger than LT1 L98 cams so expect 275 whp or so, maybe 280s my guess. Hotcam should be 300+ with vortecs. The extra lift and duration help a lot

jvaughn

iTrader: (1)

Thanks for the info. I have been toying with the idea of the roller cam, just seems pretty expensive. I know that the 305 I have now is a roller and I could use the lifters from it, but wanted to keep the motor complete to sell. If I do a roller with the same duration would I gain any HP?

Also if I did go with the HOT CAM, what all needs to be done to the heads to make them compatible?

Sparkytfl

Vortec heads like cams with a split lift/duration favoring the exhaust side. Meaning like ten higher on the exhaust. It's because the intakes flow really well, but the exhaust not even close.

You're better off not trying to port the heads yourself. Most people screw up the shape of the runners, lose the swirl characteristic, and make them flow worse than before.

You're going to want to measure your specific heads to see your max lift. Measure every valve because you might find one limiting you more than the rest. The 906s I had let me use one with a 469 exhaust, that was with about a 030 safety margin, half whats recommended but was fine. But you're best off having the valve guides cut down to allow more lift and bigger springs. But keep in mind the flow chokes up at a little over 500 intake lift.

Orr89RocZ

iTrader: (20)

Just need to find the factory spider retainer plate and lifters and the dogbone holders for the lifters and thats it. Really not all that much money if you find a guy selling a set used. Then need the factory front cam retainer plate if not already on your block and then a timing chain for an OEM roller cammed motor. Not all much to it if you have the roller block

Rollers usually run smoother and can make more power due to more aggressive lobes for similar duration. But it all depends on the cam lobe design. You can have a roller thats very tame and make less than a flat tappet hydraulic cam. I just seen alot of LT4 hotcam motors run very well and they are the most readily available cam out there used for cheap. Cant go wrong with it on a budget. Its a good 350 cam and can make over 400 hp on motor with decent heads.

jvaughn

iTrader: (1)

Can use all the parts listed about from my 305 TPI, lifters, dogbone holders? Going to go with a new timing chain, as I have been told they tend to streatch and wear out.

Also can I use most of the bolts etc from the other 350 I have as a donor? I mean is there anything that I should ABSOLUTLY replace new, other than the parts listed above? I was planning on using all the bolts, rockers, and push rods as long as they are not bent. I've heard that the roller rockers are more of a gimmick than a usefull addition.

jvaughn

iTrader: (1)

Ok, the exhaust is the first or the second number in the cam specs? ex: (1).447/.447(2)? And you were able to go to 469 without modifying the springs?

Really good info on the heads, thanks!

Orr89RocZ

iTrader: (20)

you can reuse most of the stuff from the 305 regarding valve train but replace the pushrods because you may need a different length than stock. Rockers are nice upgrade because factory arms usually dont have the tight tolerance that aftermarket ones have. Your cam lift could be way off rocker to rocker with factory stuff. Not necessary but your not getting the most out of the build with the factory rockers.

Sparkytfl

I've always seen it written with intake number first then exhaust.

I was able to use the stock springs with my cam (it was a lunati 60101 flat) without getting coil bind, but nearly anybody who's familiar will tell you that the stock springs are too weak to be advisable on anything above the low 400s. You want to keep your valves under control or you could wreck your engine. I only kept it that way for a few hundred miles of light use before pulling it all apart to use my shortblock in another car.

You do need to carefully measure (or have someone else with the proper tools to do so) every valve on your specific heads, with seals installed. Max lifts will vary depending on when they were made or which mold at the factory etc.

http://www.chevyhiperformance.com/ho...458/index.html Read this if you havent seen it yet. It explains about having them cut for more lift.

jvaughn

iTrader: (1)

Great article! I havent read that one. Thanks. So looks like I should upgrade the springs and such. Guess if Im going to go to all that trouble, might as well get the LT4 cam.

Also, if Im going to upgrade the springs, what should I be looking for?

jvaughn

iTrader: (1)

Good to know. I do have a donor 350 that has good puch rods in it, probably going to use those. Should I go with 1.5 roller rockers or 1.6?

jvaughn

iTrader: (1)

Did a little work on the heads last night. Got them all cleaned up, primed and painted. I know that no one will see them, but makes me feel better. Besides, should help with containing the rust. And I wanted to practice a bit using a spray can!

jvaughn

iTrader: (1)

Here are a few pics of the donor motor and the 355. The donor motor came from a 91 caprice station wagon. Motor had like 150k on it. It was a TBI motor, I got everything including the harness and ECM for 250.00. Not sure what Im going to do with all the left over parts.

Also have the 305 TPI thats in the car right now. Its a roller motor, so going to use the roller lifters from it.

Decided that Im going to go with the roller cam now, thanks to all the advice on here.

jvaughn

iTrader: (1)

Ok, so now I am reading is several other places that the Vortec 906 heads are good up to .460 without any modifications to them. Can anyone confirm this?

Sparkytfl

Go with 1.5s. 1.6 is more for cases of "whoops I should've put a bigger cam in".

Springs depend entirely on what's recommended by the maker of the cam you choose. But without getting the heads modified, about the only decent springs you can fit at are the "beehive" ones that are unreasonably expensive.

Don't risk it, measure the lift for your heads. Every head is different. I've seen plenty of people say they're only good to 420.

And it's still really recommended that you have those valve guides machined as shown in the article. Besides ensuring that you wont max out, it also allows you to use proper double springs with specs that are appropriate for your cam. Of course they'll have to clean them up after and there goes your new paint.

jvaughn

iTrader: (1)

Ok so witht eh behives can I use my current retainers and valve locks from the 906 heads?

andrew-wagers

i have a qustion i was thinkin bout building a 383 for my 84 z28 could you tell me the difrence in a 355 to a 383

jvaughn

iTrader: (1)

355 is a 350 bored .30 over. The 383 has a bigger crank. I think the crank comes out of a 400.

Sparkytfl

The most commonly mentioned beehives are the ones by comp. I looked at them, saw they were $180 not including the keepers or retainers (which I believe are different) and decided not to bother doing any more research on something that would cost so much more than having them properly modded and buying regular springs.

Orr89RocZ

iTrader: (20)

Cost aint too bad with those beehives. A great double spring kit is gonna run you near as much, but on aggressive roller cams, I feel the double springs are most effective at controlling valve motion.

With valvesprings, you get what you pay for. The higher quality stuff that will last costs abit more.

But for this build, you wont need much spring to control the cam you will end up putting in, so in that sense you are likely to find a good spring kit thats not beehive and still work well.

jvaughn

iTrader: (1)

Ok, so I am going to go with the Z06 springs then. From what I am getting the stock lockers will work, but I may need to get new retainers. Ive seen that I can use the same retainers that the comp beehives have, so looks like I am going to order them today.

Also ordering Self-Aligning, Full Roller, Aluminum, 1.5 Ratio rockers, LT4 Hotcam, and a set of Hooker 2451HKR Headers.

After that will order up the intake, carb, and some other acessories.

Orr89RocZ

iTrader: (20)

what z06 springs? LS6? Will those work? I know the spring specs are good enough for a hot cam but just wasnt sure of the height of those springs.

If you can find a hotcam used in the classifieds thats where I'd get it. i wouldnt waste money on that cam buying it brand new. If you bought brand new i'd try the lunati voodoo rollers or the xe comp cam grinds in similar duration.

jvaughn

iTrader: (1)

Ive read a few post on the corvette and Nasty Z28 forums that the Z06 springs work with the 906 heads. Valve Springs, Beehive, 90 lbs. @ 1.8 in., 295 lbs @ 1.250 in., .570 in. Maximum Lift, LS6/LS2

Here is a article I found on Beehive springs:
http://www.carcraft.com/techarticles...ade/index.html

Why the other cams in the same specs?

Orr89RocZ

iTrader: (20)

Alittle bit more aggressive ramps on the lobe, should help out with some power across the curve. Usually on a good head with good low lift flows like vortecs, you can make best power with a faster valve motion cam. It usually works well on most heads too but really depends on the port.

jvaughn

iTrader: (1)

Gotcha, good to know. Talk about getting a education on this site! Ordered some parts, will start posting pics as they come in, and of it coming together.

jvaughn

iTrader: (1)

Got some work done on the heads this weekend. Installed the LS6 beehives and new retainers, as well as the 1.5 full roller rockers. Wnet together really easy. Feel good about this for a first timer.

jvaughn

iTrader: (1)

Question, if anyone is still following this. I am going with the Hot Cam, and need to get a timing set. Can I use the one from my 305 or 350 or do I need to get a new? If I need a new, is there a specific one that is required?

Thanks for all the help!

nightstalker12

hot cam good choice now as for the timing set DO NOT i repeat DO NOT use a USED timing set in anything spend the extra few bucks and get u a new double roller timing set the used 1 has stretched with use and putting it in an engine with a beefed up valve train will b murder for ur engine the old 1 will break under the increased load causing u to end up replacing pistons valves heads well needless to say ull end up with a lawn ornament a new set is something like 30 bucks much betr than 2000 id say myself i recently put in a melling mtc-1 cam kit (cam lift) int. 281/ext. 296)(valve lift int. 422/ext. 444) duration 278 int/288ext. lifters new valve springs to match cam valve locks valve seals and double roller timing set all new that cam really woke up that sleepy 305and as far as valve lift goes my stocker 305 heads handled the cam well good luck

jvaughn

iTrader: (1)

Ok so its been awhile and I have finally gotten around to putting this motor together. I have installed the LT4 Hotcam, 906 vortec heads with upgraded springs (will bring me to .495/.495), 1.5 full roller rockers from summit. Now Im running into an issue. It seems that my stock push rods are short maybe? There is not much thread once I place the rockers on. The stock pushrod length I have is 7.2. Any suggestions? Has anyone run into this issue with this build?

Ozz1967

iTrader: (4)

Vortec's require special pushrods. I don't know off hand which they require, I just know stock/standard pushrods won't work. Talk with an engine builder unless someone else here knows. Maybe a search would pull up some info for you.