89newfun

iTrader: (3)

Hello, I have had an engine built by a small shop and was taken advantage of. I'm trying to figure out what was installed into my engines short block. I have a picture of the top of a piston, I was wondering if you would be able to identify anything about it. Like: brand, material, neg cc, size of the reliefs ( if able to run 2.02/1.6 valves). It's a sbc 350 .030 over. 4 valve relief dish piston. Here is the attached image. Thank you and any help would be appreciated. I'm lost in this department.
The engine is assembled and running, found the discrepancies after the motor was paid for, installed, and dynod. So I can't cc the pistons without tearing motor down, and I'm trying to avoid this. So again any help will be appreciated.

Thanks
Shawn

FRMULA88

looks like a stock 4 eyebrow piston to me.. what exactly is the problem ?

how were you "taken advantage of" ?

Ozz1967

iTrader: (4)

Why do you feel they took advantage of you?

89newfun

iTrader: (3)

We'll long story short is that I was promised a min 350 hp motor with stout bottom end. Car dynod with 230 hp to wheels. I started to dig into motor, found mismatched bolts all over engine, stock 76 c. Heads, 600 eddy carb, 2oclock balancer on an engine that is tdc timed at 12. ( just different year balancer I believe). Supposed to have given me a 2800 to 3k stall and got a stock 18 or 1900 s10 one. Changed number on me and told me it is what it is.
Engine combo doesn't add up,
Cam is for 1500 to 6500
Intake is idle to 5500
Heads are junk to big of cc ( trying to figure compression ratio, one reason for this post)
Stall is to low and car fights brakes at stop, doesnt stall car, just feels like engine brake at stop light.
Broke interior pieces and butchered my wiring harness.

And that's the short story.

89newfun

iTrader: (3)

It's my fault I guess, I didn't to do diligence in my background check on their shop. ( which was a large pull barn on property, seems like nice legit people when I visited before agreeing to motor. Paid 2500 for motor installed and they took my 305, used parts from it for the new motor too. Supposedly a zz4 block or bottom end, which I know is wrong since zz4 has flat top pistons.

But just want knowledge of type of brand, neg cc, material type, and maybe if I could run anything larger than the 1.9/1.5 valves due to the eyebrows.

Night rider327

iTrader: (13)

Sorry you did not get what you and builder agreed on... I hate to hear things like that because I am a true engine builder and work out of my home shop and work 1 on 1 with customers.

Although you didn't get what they told you, you still didnt get a 'bad deal'. $2500 built and R&R'ed is not bad. Your's is about 270 HP at crank.

No real markings on top of those pistons to ID them by, but what I see is a cast, dish (about 10-12cc) rebuilder's piston. Looks to be more than .025" in hole, so I'm guessing rather than std 1.560" compression height, its a common rebuilder piston thats 1.540 to 1.550" compression height.

Yes you can run 2.02"/1.60" valves with out any probs. The valve reliefs in the pistons do not become a major point untill you get higher in cam duration and lift and tight quench height.

The rated RPM range of parts really don't mean very much. It's just their to help DIY guys get somewhere close. What are the real specs on cam like duration @ .050" lift, lope sep angle, valve lift, etc? Or atleast cam part #.

What intake? I'm assuming based on what you said, it's an edelbrock performer.

89newfun

iTrader: (3)

Yea, I wish I've found some one not so shady. I'll post image of cam card. Also the intake is a performer, I've recently picked up at air gap though. I'm going to install that soon. Think that'll help me?
Heads are stock, and valve train is as we'll. want 1.6 rr think that will help me too? Sorry for randomness, good help is hard to find.

Question is that my converter was not electrically locked on dyno, could that make a difference.

Thank for good info so far

FRMULA88

You probably don't have enough engine vacuum to run power brakes.

a vacuum can will remedy that and will make it so much better to drive.

2 sides to every story I suppose. flywheel HP and rear wheel HP not the same

230 RWHP is pretty stout if consider drivetrain losses that engine IS making over 300 flywheel HP. from the factory 3rd gens were rated at SAE NET Flywheel HP.
so you are ahead of curve.

FWIW you CAN run slightly bigger cam (advertised RPM range) versus the advertised RPM range of the intake manifold. so I don't see problem here.. you don't want a single plane intake (with a higher advertised RPM range) on a motor this small especially on a street car.. it will kill low end torque.


the problem is the slightly bigger cam means you have less engine vacuum.. hence the need for a vacuum canister to run power brakes.. if you want even better you can do vacuum pump..

Carb size does sound right for the application..

IDK, maybe you had unrealistic expectations with a 2,000 $ budget. ? My transmission and Converter alone set me back about that much

89newfun

iTrader: (3)

Ok, that could be why slam on brakes car acts funny and dips to one side. Wot to complete braking.

Someone told me that the converter not being locked won't show actual rwhp. They said 30 to 50 hp difference. Is that true? Mine is on a switch.

The rpm air gap is still a dual plane, is it ok to run it. Think I would see a hp raise? Picked it up cheap so no loss really. 100 bucks.

What about the rr? With current heads would the 1.6 be noticeable?


So: stock rebuild pistons neg 10 to 12 cc, cast style. I'm prob at 8.5 or 9:1 I'm thinking. Pretty week. No nitrous, lol.

89newfun

iTrader: (3)

Also, some one told me 650 dp carb would wake car up, right or wrong ?

Night rider327

iTrader: (13)

Don't buy into the bigger is better. The 650, or 680, or 750 carb is NOT going to help.

For street use a 600cfm is perfect for your engine and needs. I ran a 600cfm carb on my 355 daily driver well into the 11 second range (best was 11.40's @ 118 mph), at that point yes a bigger carb would have made more power, but the smaller carb had better street manners.

The cam is WAY too big for your compression. I would want 9.8 to 10.2:1 compression with that cam.

Right now your performer intake is a better suited match to your engine.

The only 2 things you can do right now to really improve the engine is.....
1) cam swap to a smaller cam
2) and the best option... Replace heads with better performance based heads and smaller 60-64cc chambers.. At that point the RPM air gap would be a better match.

As it stands right now, your compression is really low. Depending on head gaskets used and true deck height your compression will be in the 7.8 to 8.5 range

89newfun

iTrader: (3)

What carb did you run?
And I would love to do heads, just wife doesn't see why spen another grand when I just had motor built, the shady shop said that they were shaved down so maybe 72 and max cut to 70 cc.. Who knows if that's true or not.

Night rider327

iTrader: (13)

I ran an edelbrock 600cfm man. choke. I did mod the carb alittle, smoothed out some of the transitions, dailed in the jetting/rods/springs, removed choke, etc.

I now run a Holley HP 750 cfm on that car but have more head, cam, gear and stall now. It's more of a drag car now. My driver now is a S10 with 355. Vortec heads, 216/228 @.050 cam, performer intake (modded), 600cfm edelbrock carb.

I can fully understand not wanting to do a head swap right dropping $2500 on an engine.
If the heads have been milled of course the compression will be higher, how much higher depends on how much was removed. Anyway to ask builder how much was cut from the heads?

2005Impalla

Your pistons look a lot like the 12 cc dished pistons used in my vortec 350. I would try to get some better heads and I would run a larger carb like a 650 if your shifting at 6,500 RPM. The other and probably better option is to just keep every thing how it is and get a smaller cam. I would get something that followed the power band of your intake, something that will pull to 5,500 RPM. Your intake, heads and carb should all be able to handle a little over 300 HP at the flywheel with a different cam. Stock 1.94 heads our usually good for up to 350 HP if you have enough compression and the right parts but being your compression is probably in the 8s your probably capable of building a 300-325 HP motor with the parts you have.

89newfun

iTrader: (3)

I have and 3 different answers. Most accurate was being like 72 cc. But again who knows they pretty much hang up on me ever since I started asking questions about the parts within the motor. Hard to even text or call them anymore. Sorry no help there.

Dyno guy said some on the table with carb tuning and bigger carb. Who knows, torque was at 275 rwtq. Which isn't bad I suppose. What heads would you guys recommend, not going vortec or alum? Possibly a stock head option that would liven it up and not break the bank.

89newfun

iTrader: (3)

What cc did you get out of your car, vortec is 64 cc, so 9.5:1?

2005Impalla

I did not cc my heads so I am not for sure. I ordered a vortec crate motor and had to machine them to fit my valve springs because my valve guide boss was to large and I wanted screw in studs as well. They say my compression is suppose to be 9.4:1 Your pistons should easily except 2.02 valves as long as your not running a cam with a lot of lift. Any thing in the low .500 lift range or lower should be fine. You know I just looked at your cam card while I was writing this and think the carb, cam, and intake are matched just fine. I would run the same set up my self. I am betting your problem with power is low compression. I retract my last post and think you should find a different set of heads that will raise your compression. Track down some aluminum L98 heads from some one, get a new stall converter and you should have a good set up. The performer says 5,500 but it can pull a little higher than the recommended power band and most intakes can. A RPM would probably make more power but your low compression is holding your motor back the most. If you have 12cc pistons your compression is probably near 8.5:1 or a little lower. Heads are were the power is at and the better they are the easer it is to make power. If you could afford it some aftermarket heads would be best. Even some cheep summit heads would be better than tracking down some good stock heads.

Night rider327

iTrader: (13)

Oh BTW, no you do not want to add 1.6 rockers to that engine. Cam is already too big for what you have. The rockers will just make it worse.

GM vortec heads are listed as 64cc but ever one I have checked has came up at 62 or 63 cc.

I know you do not want to hear this but a set of vortec heads would be the best answer for you. You will gain 60-75 HP at crank, get your compression up, etc.

If you use fel pro 1094 head gaskets (.015" thick), we assume 12cc dish pistons, .045" down in bore (rebuilder pistons) and vortec heads, your compression would be around 9.3:1
If the pistons are the correct compression height and sits .035" in bore you would be at 9.55:1

If you shop around, the vortec heads can be the cheapest stock option. Other good useable stock performance heads are rare and high $$$... Not very many options really.. L98 iron heads, L98 alum heads, and 40-50 year old double hump heads that will need a ton of money put into them.

I looked in Detroit MI CL and came up with these
$200 http://detroit.craigslist.org/mcb/pts/4839066620.html
$500 full 350 vortec engine.. You could pull heads off and resell the short block for $300-400
http://detroit.craigslist.org/wyn/pts/4834801066.html
$300 http://detroit.craigslist.org/mcb/pts/4871595096.html

Sell your performer and RPM air gap intakes, buy a summit stage III vortec intake, $45 valve springs, $15 +.050" locks, Fel pro $55 MS980000 intake gasket set, $45 fel pro 1094 head gaskets.

You will rockers off center bolt valve cover heads or the vortecs (2 of the above listed has rockers)

Then use the cam you have, carb, etc

2005Impalla

If you don't want aluminum than I would say the iron L98 heads. I believe the iron heads use a different intake bolt angle on the 2 center bolts though. The aluminum L98s have a slightly smaller chamber at 58cc instead of the irons 64 and will allow you to reuse your intake manifold.

89newfun

iTrader: (3)

L98, I'll start browsing them. Some heads I've found are 790 pair for no name aftermarket heads, which may need extra machining to clean em up. I def need a bigger stall, thinking 2600 to 3200. Just takes money, lol. Wife and kids are a pocket book security team, hah.

89newfun

iTrader: (3)

Awesome info here, I thank you much. I've looked into vortec before, but with just getting the intake I was thinking I would save a bit due to the cost of vortec intake. Also my cam is max for vortec I think, or .500, I can't remember. I'm definitely going to hunt 64 cc heads to bring compression up.
Could I run the heads from donor motor right off the motor, no work. Or do I need to do the springs and retainers? Just curious. Might wait til next year this time to do it since I just put a grand into rear end.

89newfun

iTrader: (3)

Could I actually do 58 cc? Someone told me quench area wouldn't be able to get set right, or something like that.

FRMULA88

Just get a set of Dart Iron Eagle heads, 64 CC chambers, 185 CC runners
a bigger engine like a 383 you would use 215cc..

way better than anything you can get from the OEM.

If you want Alum try AFR

either way everything will bolt right on

Ozz1967

iTrader: (4)

You need to take a breath my friend.

WIth your cam, 2200-2400 stall would be just about perfect.

With as low as your compression is, you want to get a better flowing head with a lower CC. Your cheapest option would be a set of 64CC L98 heads. Better than what you have, only because it brings the compression up. They'll flow about the same.

The best cheapest option is what was mentioned. Sell off both of your intakes and heads, and buy a Vortec intake and Vortec heads.

FYI, until the introduction of the LS motors, the Vortec Heads were the BEST factory head GM ever made. EVER.

You can find them for $300 for a set used on many web sites. You can then have the minimal work needed to have them accept .500 lift to match your cam.

To give some comparison.

I started with a used 350 block with a spun bearing. After buying all the parts myself to save money and then having the shop prep the block and do the assembly, I was into the motor, just the motor, over $4000. It was north of $6000 once you factored headers, exhaust and some other stuff I needed to get done once it was in that I broke and had to fix.

On a dyno, my 355 has 262 rear wheel Hp and 281ft-lb of torque.

Your motor isn't too far off that now. You just need to tweak it.

2005Impalla

Ya I am about $4,500 In to my motor as well. Its just want it cost to build a whole motor. Ozz is right the L98 heads will not flow much better they will just raise compression. The aluminum L98 heads will work with the 58 cc chambers just fine. The compression will probably be just under 10:1 which is fine for aluminum and would wake your motor up. Who ever told you the quench thing did not know what there talking about. I would swap the spring from the motor you are running now to the new set of heads unless you get some new aftermarket heads because you already know they work with the cam you are running. I also agree with Ozz on the stall. A 3,000 would make the car a little faster but I don't think it is worth it with the cam you are running and would stick to a 2,200-2,500 stall unless it is a strip only car. Wait tell you get new heads on the motor, re adjust your carburetor and timing then see if you still think you need a new stall.

2005Impalla

A better 2,500 RPM stall might not pull like the cheep one you have now. A torque converter designed for the torque of a small block instead of a 4.3 V6 might have a true stall speed that's higher than the one you have while still having the same flash stall speed.

Ozz1967

iTrader: (4)

Unless he wants to drop $800 on a truly good converter.

89newfun

iTrader: (3)

Ozz and impala again I thank you for great advise.
My original plan was a vortec motor with 1.6 and airgap with a 750 dp. The shop talked me out of it saying this would be cheaper and would perform the same. I was naive with the decision obviously. I've seen bbth these choices, Vortec or camel hump heads with or without accessory bolts. Would either one match with equal work done to both. Port on the camels and valve spring work on vortec. This is a street mostly car maybe a couple trips to track a year, bracket race or two. So your right a lower stall is prob better and streetable. Most convertor I've looked at are 800 as you mentioned since u have a lockup.
So I guess 2500 isn't so bad to swap 305 to 350 I guess. Just bummed I didn't get what was discussed hp wise and then they became like ghosts after I trailered the car off their property.

89newfun

iTrader: (3)

Funny these heads come up again. Friends tell me to just wait and hunt for these heads to pop up on Craigslist. Matter of fact there is a set on there now. Sucks cause I can't jump on anything now. But through all your guys help I will have a solid plan of attach once this money tree grows back a little.

89newfun

iTrader: (3)

Also I hadn't seen your advise on whether or not a unlocked convertor can show a hp difference on a dyno compared to a locked convertor . I did research on another site and they posted actual results of runs with and without locked convertor. Only car that was similar was a 92 lt1 with same 700r4 trans. It ran a 40 hp difference between the locked and unlocked. Explained this to be due to the convertor absorbing the power rather than transferring it directly to trans. Any truth to this you think?

89newfun

iTrader: (3)

Anyone with advise or previous knowledge of hp difference with converter locked vs unlocked on a dyno? Based on example from previous my post.

Ozz1967

iTrader: (4)

Not sure why your concerned about it. The converter won't lock on a dyno Unless you let it or have it on a switch. The difference is less than 10hp

skinny z

Have you done a compression test? If not, do one and post your results Your compression can be reasonably calculated with the right amount of data.

89newfun

iTrader: (3)

Just because I was told its a more accurate result if it's locked.

89newfun

iTrader: (3)

I'll borrow a compression tool maybe during week, that's my weekend. Once I do that I'll try to post the results. If I don't get it done soon, I'll pm you skinnyz on the results and can help further.

Ozz1967

iTrader: (4)

a locked converter actual sucks some hp. The converter isn't locked when you do WOT runs, so that's when and how you should test it.

couchmotors

2500 is not a bad price for.what you have got. Hell my bottom end cost that much.anyway you have a good starting point for what your tryingdo do. I would find a set of dart heads like mentioned before. They will do wonders. Lanuati has some very good cams for.what you tring to do and it will help with hour vacuum issue. As for camel hump heads you will have issue with your accessory cause there are no bolt holes in them you will be better off with vortec if you dont want to buy dart heads. The vortec top end will help in search for more power. And bigger is not always better in a small block

couchmotors

Remember this torque is have far you move the wall and Hp is have fast you go through it.you need to find middle ground torque is what gets you off the line and horsepower is how fast you go on the topend. Also you only have a 2:73 gear in rearend. So until you change that your off the line is not going to be very neckbreaking

skinny z

We have most of the info to do a reverse calculation. Bore, stroke, rod length, advertised intake duration, lobe separation and intake centreline. The only other variables are your elevation, the ambient air temperature during the test and of course the results of the compression test.

FRMULA88

http://www.dartheads.com/products/cy...der-heads.html

save some money.

check out the flow ratings on the 180 cc heads.

with these heads you could used 1.5 rockers on the intake and 1.6 on the exhaust..

the other plus is you can retain your current intake manifold.

if you can get flow data on the glorified vortech heads you will see they leave a lot on table compared to quality aftermarket parts..

My advise is never skimp on heads buy best you can afford. Dart also has a CNC ported version this head.. just navigate their site and check the tech data.. and if you want them in aluminum
they have that too..

FRMULA88

lastly don't get hung up on what the chassis dyno says... someone else's dyno will say something else.

The best gage is a time slip !

89newfun

iTrader: (3)

I've been really looking into dart iron eagle 180 heads. For the price I can find them used, can't really beat them. Then I can use the air gap with 1.6.
What is the benefit to using 1.6 and 1.5 rockers vs all 1.5 or all 1.6?
It will be at the track this spring due to new posi rear end installed. Sit and spin one leg before, not a real good gauge on cars build . Lol. I'm thinking 14s, is that realistic with current setup?

FRMULA88

with your camshaft you don't need more than .500 lift on the intake with these heads, so 1.5 rockers should be fine on the intake.

But you will gain better scavenging / charging of the cylinders with 1.6 rockers on the exhaust because these heads flow better on the exhaust with a bit more lift. ( .600 lift )

since your cam is not a dual pattern (meaning both intake and exhaust lobes have same duration / lift) you can accomplish this with slightly higher ratio rockers on the exhaust valves.

This is a trick I learned from a veteran builder.

86LG4Bird

iTrader: (1)

I just saw this thread and can chime in with more info on how much hp the TC can "absorb" on the dyno.
If you have anything like a stock converter, an S-10 converter, or ANY quality converter below 3000 stall, expect less than a 5hp difference between locked and unlocked. The only way you would ever see a 40 hp difference is with either a completely screwed up TC or by operating something like a 4000 stall converter with an engine that produces peak power at 5000 rpm.
I've run quality converters (Vig 3000, Yank 3000, and Yank SS3600) on dyno's and observed a maximum difference of 2 hp , That's right.... TWO HP, between unlocked and locked. With a cheaper brand 3400 stall converter behind a motor that power peaked at 5300 rpm, the difference was about 18 hp. Running an 8" non lockup 4200 converter behind a 540 hp motor peaking at 6400 rpm showed about 20 hp less than a locked 3600 converter behind the same powerplant. But it went down the 1/4 quite a bit quicker
Ozz, I'm not sure what you meant with the comment: "a locked converter actual sucks some hp", but unless I'm misinterpreting what you said, I have to say that's not the case. Locking will always show a better dyno number than unlocked.

89newfun

iTrader: (3)

Awesome, thanks! With the dart heads as example right? So keep in mind flow number on intake and exhaust, if exhaust flows better with larger lift, help it with 1.6 rr. Got it. Love the old tech tips with explanation. Thanks

skinny z

Keep in mind too that a lot of street cars suffer from a poorly designed exhaust system. One that doesn't have sufficient CFM and consequently develops backpressure. Something that's very common on the typical 3rd gen with its limited room for a decent dual exhaust. Adding to the exhaust lobe will help overcome that to some degree. That's part of the logic behind a dual pattern cam although such a cam has it's drawbacks.

89newfun

iTrader: (3)

86LG4Bird,

Thanks for chiming in. I pretty sure that they put in a stock s10 converter, doesn't stall real high. Actually feels like same as the 305 stall, maybe they just painted it and again took me for a fool. But I'm guessing I would see a whole difference, also I definitely feel a stronger pull with converter locked. But I hardly do that, iirc the the fluids won't flow through cooler with converter locked, right? 2500 stall still best suggestion?

89newfun

iTrader: (3)

Speaking of exhaust let me run this by you.. I currently am putting exhaust on car now, slp cat back 3", custom 3" ypipe. Slp bullet muffler. Think this will be good or to much exhaust for the car?
Got the slp for 100 and ypipe for 60, couldn't pass on it.


Image of stuff

89newfun

iTrader: (3)

Also, if I were to get a ss dart iron eagle, could I use the guts from current heads, valves springs retainer ect.
Only asking, cause 202 16 valves with a 64 cc combustion a nd 1.6 on exhaust I don't want the valves to interfere with the eyebrows on those pistons. What's max lift with 64 cc heads could I go to keep from slapping valve into the eyebrow cuts?

86LG4Bird

iTrader: (1)

Don't let that seat-of-the-pants impression fool you. Yes, of course at any given rpm (typically you're at part throttle when you make the observation you noted), it truly does accelerate better locked. BUT....a brisk or WOT acceleration up through the gear changes will have the best average acceleration with the TCC unlocked. I'm sure you already know this, but don't ever keep the TC locked through gearshifts; broken hard parts won't be far in your future!
Although reduced, there is still sufficient flow through the cooler when locked to keep temps in check.