Upgraded heads recommendation for my 87?

[Skunksmash]

My old truck just needs more power. Its not gutless, but its pretty far from great too. So I've got a few questions regarding upgrading the cylinder heads on my 1987 Silverado 5.7L. It has the stock engine. I'm looking to just bolt on a new upgraded set of heads (and maybe a few other necessary parts) and leave the stock bottom end. Not looking to pull the engine out or anything like that.


1. What are the best possible bang for the buck heads that will fit my 87 350, that are cast iron? Please be very specific because I'm not real familiar with this topic.

2. What are the best bang for the buck heads, that are aluminum?

3. Is there any reason I should buy aluminum instead of iron?

4. What kind of power increases can be expected from both sets? I assume that by now, that should be pretty well known by the 350 community.

5. What other parts should also be bought at the same time, to maximize the potential of the new heads? Don't want my old stock parts to be choking them out and hindering their power somehow.

6. Is there anything else that you think I should know, regarding such an upgrade? Please keep in mind that I just haven't dealt much with these old 350's. Aside from standard maintenance and just replacing consumable parts like spark plugs and distributor caps and oil pressure sending units and the like. Most of my work in daily life, is all done on modern engines, usually 4 cylinders like hondas and toyotas and such.

[Big Port Jimmy 6]

Well a motor is a motor is a motor. The same basic theories apply. Anything that nets more efficiency moving air from the intake to the exhaust is going to help with power. Now some questions for you.
Is it a TBI truck?
What kind of mods are already done?
If none perhaps there are some things to do before heads.
(Headers, Exhaust Intake etc)
How much power are you wanting?
Mileage and overall condition?
What's your primary use for the truck?

Jay

[bbbc10]

If its a factory tbi i would keep it like that......they make a intake manifold for tbi.....i would say stock vortec heads but u will have to ditch all the factory tbi stuff an run a carb setup....some longtube headers if ur not really low an exhaust

[Skunksmash]

Originally Posted by Big Port Jimmy 6

Well a motor is a motor is a motor. The same basic theories apply. Anything that nets more efficiency moving air from the intake to the exhaust is going to help with power. Now some questions for you.
Is it a TBI truck?
What kind of mods are already done?
If none perhaps there are some things to do before heads.
(Headers, Exhaust Intake etc)
How much power are you wanting?
Mileage and overall condition?
What's your primary use for the truck?

Jay

Yeah its a TBI truck. Don't really want to mess with a carb.

The only mod done to the engine is a CFM tech brand throttle body spacer.

For power, I'm not real sure. I think I'd want to net at least 50hp/50tq. At least. 100hp/tq would be great, but if that's not feasible due to price or road manners, I'll accept less. Like I said, the old girl needs a kick in the seat of the pants.

I can't be sure on the mileage. I really have no idea, since those old odometers only went to 99k. If we assume its rolled over only once, it would be 153k. Which, given I'm the second owner of the truck and the good condition that its in, might actually be true. But I can't say for sure.

My primary use for the truck is... well its really just a street truck. I use it to tow the boat to the lake, to go get parts from the parts store, groceries, hauling that a half ton can do, etc. Pretty much all a normal truck's duties, but I do need it to have road manners.

As for mods before the heads, I'd like to just do it all at once and get it over with. So once I'd settled on heads, I'd be looking for the right intake. Then of course I'd go ahead and put the longtubes on, since I'd have it all apart already anyway. So I want to have all the parts ready to go on at once.

Originally Posted by bbbc10

If its a factory tbi i would keep it like that......they make a intake manifold for tbi.....i would say stock vortec heads but u will have to ditch all the factory tbi stuff an run a carb setup....some longtube headers if ur not really low an exhaust

Yeah I will definitely be keeping the fuel injection system. I'd also already planned on some nice longtube headers, once I bought the heads. I didn't know you had to ditch TBI to go with votec heads.

[Nick_R_23]

If you have a TBI truck, the heads are what are initially limiting you, followed by the TBI system itself. It's not a very performance oriented setup in any way. You probably would never see much benefit from aluminum heads, other than weight savings, as the rest of the engine (TBI unit, intake, cam, and exhaust manifolds) will never reach the heads' flow capabilities from a stock system. Your best bang for the buck would be 5.7L Vortec heads from a 96-00 truck. You will need a matching intake manifold as Vortec heads utilize a different intake bolt pattern. I believe TBI-to-Vortec aluminum intakes are available now to bolt the TBI throttle body directly to the Vortec setup with no adapter plates. Headers will help a bit, as will a camshaft, but you will be limited to basically Police Package/Corvette cam specs, as the TBI system gets picky and likes to throw EGR codes with even mild cams such as those. The TBI unit itself will ultimately be your limiting factor, as you are basically working with an electronic two-barrel carb.

Edit: Here is the intake you would need to run your TBI directly on Vortec heads http://www.jegs.com/i/GM+Performance...FQ5EfgodQr0HeA

[Dead Parrot]

I recommend you get a compression check done on your existing engine before you do any buying. No point in putting hundreds of dollars of new parts on a wore out lower.

Spend some time browsing the Jegs and Summit websites. They will give you some price info before you get too settled on a solution. And you can see what adapters are made for what manifolds etc.

You might also consider buying a crate motor. I know you said you didn't want to pull the motor but it might wind up being a lower cost solution. And if you pull the transmission at the same time, you can have those leaky seals replaced.

[Big Port Jimmy 6]

This guy seems to have the TBIs figured out, but I have no proof so Caveat Emptor.
http://tbichips.com/?page_id=73

And I'll agree with what Nick said above.

[chris989]

Skunkmash,

Here is my TBI build. I have about 2500 mile on it and could not be happier. After some simple tuning experiments I reinstalled my OEM chip with zero modifications. I get ~14 mpg around town.

I just towed my 8500lb camper up to McCall, Idaho and did not have one issue. There are some really steep grades that slowed to 45mph on but honestly it was winding road anyway.

http://67-72chevytrucks.com/vboard/s...d.php?t=696544

Not sure of your tire size and gears but for return on investment maybe gears and an OD might be more power were you need it???

[Malo83]

Try a bigger Holley TBI, good reviews
http://www.jegs.com/i/Holley/510/502-6/10002/-1

[Skunksmash]

Looking at all the costs that everyone has laid out here for me...

Its probably better just to upgrade to a 5.3

[chris989]

Originally Posted by Skunksmash

Looking at all the costs that everyone has laid out here for me...

Its probably better just to upgrade to a 5.3

An LS swap is 100 percent diferent motor. unless you have a complete doner it will be more $ than you thought.


Lets not over look the simple stuff.

what is the condition of you current motor? Compression, wipped cam? distributor slop, chain slop?? if the motor is toast, get a new one for 1600 and be done. after selling my core motor i was in the new motor 1300$
http://67-72chevytrucks.com/vboard/s...d.php?t=696544


What gears are you running? tire height?

you can put thousands into a motor and if you have 278 gears it will still be a dog.

find out and post what you have to start with and you will get real world options.

the OEM swirl port heads get a bad rap but under 4000 rpm they do what they are designed for. low rpm torque, not a lot, but for a tock motor it does ok IMO.

[Skunksmash]

Originally Posted by chris989

An LS swap is 100 percent diferent motor. unless you have a complete doner it will be more $ than you thought.

what is the condition of you current motor? Compression, wipped cam? distributor slop, chain slop?? if the motor is toast, get a new one for 1600 and be done. after selling my core motor i was in the new motor 1300$
http://67-72chevytrucks.com/vboard/s...d.php?t=696544


What gears are you running? tire height?

Yeah it always ends up being more money than you thought. The current condition of the motor is... well fine I guess. Can't complain. I haven't done a compression check yet but my guess would be that its probably ok. Although it does burn about 1.5-2.0 quarts before its time for the next oil change. So maybe there is some issue there. S

Far as I know the cam is ok. Distributor doesn't seem to have any slop. Stock tire height, and I believe it has the 2:73 gears, or whatever the equivalent is. Its got a 700R4 and in 4rth gear it will do 80mph at what looks like about 1900 RPM. (got autometer rpm gauge now instead of giant fuel gauge) I guess you really can't fault it for being an old engine from 1987. It will still squeal the tires pretty good if you just floor it from a dead stop. (no power braking)

And, I'd say its still got a reasonable bit of its power left. It will still pull the pontoon boat up a hill, although at that point you can feel that the power has drained somewhat. So the ol girl really just needs a boost. And I was thinking something like 100hp/tq would really wake it up. Help with pulling the boat up hills and such.

[chris989]

If you are running 278 gears and an OD I would honestly start there.

I now run 456 gears and 33 inch tires. sort of puts it back to 411s if i have stock tires.

If you have OD already, I would swap to 411 gears for a few hundred$. The gears will make the biggest single improvement for performance and it will be the cheapest.

after that, in order i would modify;

exhaust
cam/timing chain. sometime the chains get so much slob the cam an be retarding and ruining what tiny performance it had OEM

Did you get a chance to read my TBI build. You can always PM me or call to discuss.

Chris

[rfmaster]

TBI system in itself is not a limiting factor - it does need some love!

Plain and simple - swirl port heads were designed to provide low end torque under 4300 RPM. Commonly found on 5.7L LO5 engines (87 to 95 various applications) with 11402193 heads that have 65 +/-1 CC combustion chambers. Other casting numbers are 191, 810.

Question is how much more power do you want and what is you budget?

Stock LO5 engines were rated around 190 to 210HP (optimistic) depending on application. GM TBI system can easily support 250 to 275HP at higher fuel pressure, or with BBC injectors and different timing maps. The problem with a stock LO5 is a tiny flat tappet camshaft: 0.382/0.402" I/E, @.050 166/174.8 deg, LSA 112deg and restrictive heads.

A very common upgrade to LO5 (while retaining TBI) is to ditch stock cam and heads. Since bottom end is not coming out you'll have to live with stock dished pistons, which are okay for stock to mild builds up - 250 to 275HP levels.

If you are on a tight budget I would suggest first find your block casting number. Since you have 1987 truck you may have a block that has roller cam spider bosses cast, but not drilled and tapped. This requires intake removal. From the factory truck LO5 were equipped with a flat tappet cams. Car version of the LO5 (Caprice) were equipped with roller cams! It is likely that you may have a roller compatible block that was not drilled and tapped to accept the factory roller lifter "spider" in the lifter valley or the cam retaining plate behind the timing chain gear. The block can be drilled and tapped by you or machine shop and then a roller cam can be installed. If your block happens to be drilled and tapped even though it has a flat tappet cam in it right now, then you're all set. Once you figure this you can select which type of camshaft you can use. Since today's oil contain low Zinc it is better to go with a roller camshaft. It is very common to wipe out brand new flat tappet cam running today's oils.

If your block has roller cam shaft provisions you can go with either roller or flat tappet cam.

On the budget.
ROLLER - a used LT1 cam is hard to beat and it will work with TBI. You'll need roller lifters, spider plate, dog bones, camshaft retention plate (there are two different types depending on the block mounting holes). For an exhaustive and detailed information on LT1 I would recommend this guide.
http://www.thirdgen.org/forums/tbi/2...-ultimate.html
A milder (dirt cheap) approach is a Vortec camshaft 12530282 191/196deg I/E, 0.414"/.428" I/E lift; 111º LSA. These cams can be pulled from JY L31 donor together with all needed hardware (spider, dog bones, lifters, plate + bolts).


FLAT TAPPET
Numerous choices, but you must get a 'computer compatible' cam! My past choices that worked with TBI: CS-1014R; CS1105R; COMP Cam 12-262-4; Lunati 30138; Summit SUM-1102 (same spec as CS-1014R)

Once you know what camshaft you can go with cylinder head selection becomes a bit more clear. Separate post on cylinder heads, but in a nutshell it is tough to beat (money and performance) a brand new, complete after market AL or CI heads from Summit, Jegs, SW, + others. Just make sure that you have 87+ intake compatible holes drilled and tapped and the head is setup for the camshaft that you're running. Look for 64 to 65cc heads. 68+ cc heads are too big and you will loose compression!! You want at least 9.0:1 or higher for performance depending on the gas that you run.

//RF

[WorkinLonghorn]

I must have missed it, what were the results of a compression test on each cylinder ?
If this hasn't been done then do it now or even a leak-down test.
Dead Parrot already asked this but I didn't see an answer. Brian

[Skunksmash]

Originally Posted by WorkinLonghorn

I must have missed it, what were the results of a compression test on each cylinder ?
If this hasn't been done then do it now or even a leak-down test.
Dead Parrot already asked this but I didn't see an answer. Brian

Haven't done one yet, but I do have a compression tester. I was just seeing if it was really even worth it, and getting some good ideas and comparisons.

[Nick_R_23]

Time for a 6.0L!

[Skunksmash]

Is the 6.0 any better than the 5.3? I'm sure it has a bit more power, but how are things in terms of fuel mileage?

[Skunksmash]

Also, there is this option. These guys seemed to do pretty well with this thing, and I could just take their advice on fitment and boost control into account. Plus, I'm not looking to gain their kind of power. So maybe I could even go with a smaller turbo, and have less turbo lag.

https://www.youtube.com/watch?v=oFLqaSNp45Q

[chris989]

Originally Posted by Skunksmash

Also, there is this option. These guys seemed to do pretty well with this thing, and I could just take their advice on fitment and boost control into account. Plus, I'm not looking to gain their kind of power. So maybe I could even go with a smaller turbo, and have less turbo lag.

https://www.youtube.com/watch?v=oFLqaSNp45Q

I think you need to realize what your end result needs to be. Racing, DD, offroad?

the turbo looks like a mess, I can't imagine the amount of fab work to install it in the real world. I know of a few guys that added turbos to motors and the next step was new head gaskets.

If you want to blow;
5k, go LS swap.
2-3k go vortec swap.
1-2k follow my build
500$ install a set of gears.

But without knowing what you have now, we are all guessing. No one has any ideas what to compare anything to.

If your motor is worn out, a stock TBI will be an improvement.
If you have 278 gears, 411 will blow you away.
if your motor is fresh and you have 373s you will need to go vortec or ls for improvements.

Good luck

[chris989]

here is that same kit installed in a truck, looks like he has a ton of headaches and had to cut the frame on both sides.


https://www.youtube.com/watch?v=M44XCYqgBCI

https://www.youtube.com/watch?v=U2FMv0yM-0A

[Skunksmash]

Originally Posted by chris989

I think you need to realize what your end result needs to be. Racing, DD, offroad?

the turbo looks like a mess, I can't imagine the amount of fab work to install it in the real world. I know of a few guys that added turbos to motors and the next step was new head gaskets.

If you want to blow;
5k, go LS swap.
2-3k go vortec swap.
1-2k follow my build
500$ install a set of gears.

But without knowing what you have now, we are all guessing. No one has any ideas what to compare anything to.

If your motor is worn out, a stock TBI will be an improvement.
If you have 278 gears, 411 will blow you away.
if your motor is fresh and you have 373s you will need to go vortec or ls for improvements.

Good luck

Thanks for the replies.

I really like being able to do 80 mph at 1900rpm or thereabouts. Wouldn't even just installing 3:73's pretty much kill my low RPM highway cruising? Seems like 4:11's would utterly destroy my good time cruising on the highway. Which I do a lot of.

[chris989]

Not sure if you will ever get the answer you want to hear.

If you want power to the ground you will need to change the 278 gears. You can find 373 gears all day long for just about free. I threw mine in the trash after my swap. Install them in and check it out.

You might be surprised that if the motor is is working more efficient you might get better MPG even with more RPM.

If you do the gear swap, verify MPG before and after. Also, if you have a vac gauge, get some readings at cruise speed before and after. You can always go back to 278s


With 456s and 33s tires, similar to 411s with stock 28, I cruise ~70MPH@ ~2300.

If you want to cruise at 80 and 1900 RPM you might look into a set of 2.41s

You are trying to push a ~5000lb brick into the wind. You want power, cruise speed and MPG. pick two for a compromise. pick one for the best results.

[Skunksmash]

Well I've pretty much got my answer. The 350 really isn't what I'm looking for. Another question for you:

Did you ever get the burb in the link dyno'd? I'd be curious to know what its final power numbers were. Also, what kind of mileage does it get around town, and on the highway. Also, have you verified that by doing the math at the gas pump.

Honestly even now, when not towing, I've got nearly no problem with the power the truck has. While of course its not "fast", it will get out of its own way. Its usable on the highway. I can pass other vehicles no problem, and use the fast lane without everyone trying to get around me and without drinking gas. I think that I actually like the gears that it has, pretty well. While I'm not going to win many races, it fulfills its function ok.

But I did say "nearly" no problem, cause we've all been to that place where we'd like that bump up to the next level in power.

[Nick_R_23]

If you want to get a little more kick with what you have for now and still keep it budget friendly, the Vortec heads, conversion intake, and decent headers will wake it up a bit and keep the cost down. In addition, add better gearing without losing highway drive ability, 3.42s would likely be a nice compromise. That is about as bang for the buck as you can get and still gain power while keeping it budget, and not diving into a huge conversion project.