89iroc-z559

Okay here's the thing this is going my first car that I'm goin to upgrade and I don't know were to start. First of all I have a 89 Iroc-z 350 auto. I read that these motors are supposed to put out 1 hp per cubic inch so that's wat I want.
I just don't know how to get there. So I was wondering if u guys could help. I've searched 350 builds but havnt found anything. So yea if u guys could help I would appreaciate it. Keep in mind I'm not very knowlegeble on mechanics but planning to learn along the way. And this is my daily driver. I have to take it to work and college so yea any help is greatly alpreaciated..thanks again

gcgarner

How do you get 350 hp out of that motor? Money. A lot of money.

You are looking at some serious modifications. Not the kinds of modifications you want to be doing to your daily driver. My suggestion is to enjoy the car as it is while it is your DD, then whenever you get a new DD, keep this car and start your mods.

For the time being, if you want to do some easy mods that don't cost too much (some are more expensive than others ... some are FREE), I would start with subframe connectors and maybe a wonderbar steering brace if the car doesn't already have them. Then move on to a cold air intake, headers and a cat-back exhaust system. You might want to learn a little bit about DIY tuning, also ... or find somebody that can program chips for you to support your mods. Look up "free tpi mods" on this forum. The throttle body coolant bypass is one of the easiest. Doing little things like these will help you learn along the way. A tranny shift kit and a rear-end gear swap are my personal favorites I have done to mine.

How many miles are on that motor? If you are looking for 350 hp, it might be a better move to just eventually buy a new motor. You are most likely going to have to put a power-adder of some sort on there for that kind of HP. But I might be wrong.

One drawback of having that kind of power in a third gen is that the 700r4 and the 10-bolt rear end weren't designed for that kind of power.

Z2EIGHT

Heads, Cam, HSR or other aftermarket intake and lots of professional tuning.

Quinny

I had this same discussion on a Corvette forum over the past few days.

I believe that the 89 IROC has the same L98 engine from the C4 Corvette - so this is what I learned:

1. Horsepower figures are overrated, especially when you are talking about the L98. They are built for low down torque, and the intake is what makes it - but it means less revs and therefore lower horsepower figures.

2. You need to decide whether you want dyno figures/race car or street driven torque monster.

3. Getting a set of higher flowing intake runners, and base plate helps alot to help the engine breath better above 4500rpm without sacrificing the great low down torque. Edelbrock and TPIS both make a stock replacement for the L98 intake which is a bolt up replacement for the stock one, using the standard plenum. The TPIS setup is better, but is more expensive.

4. The heads are also designed for low down torque rather than high horsepower. TrickFlow Specialties make a good set of alloy heads based on the L98 original, but with 195cc runners, and much better overall.

5. Don't be tempted to go for too big a cam. Even with the bigger cam and heads, the engine will only rev to around 5500rpm, and will make massive torque by 3000rpm. Something like the Comp Cams 218/224 cam should work well.

6. A good exhaust system is essential - again, don't go too big, 1 5/8" Tri-Y extractors and twin 2.5" pipes is plenty.

7. If you want a high revving strip monster, then go for a big cam, increased compression, high flowing heads and change the intake manifold to something like a SuperRam.

I hope that helps.

ap72

Running ported 416 heads (with 1.94/1.6 valves if you can swing it) with a good cam with about 220/225 duration @ .050" and .5"+ lift, long tube headers, a superram intake (or the very least a converted LT1 intake), open exhaust, and a good tune will easily get you there, you're a also looking at about $1500 for parts. Its a good street combo that's very durable though.

If you stepped up to some RHS heads or something of that nature you could easily surpass 450, but it'll cost ya another $500 or so.

89iroc-z559

so since i dont know how to build engines this is the setup that i am gonna try to get. Please let me know if this will work or if this is all i need to make this work. i am gonna get the Wieland vortec intake manifold from summit prt #7542, then the GM perfomance vortec cylnder heads prt #12558060, then the holley efi fuel rails prt# 534-186.
please let me know if i am missing something to make this work or if the vortec setup is really worth it or if there is something better and cheaper out there. since i dont really know alot besides just doin maintenence on my car amy help will be appreaciated.
also i hear that people talk aboout cams really often
. but i have no idea what cams are so if some can explain what they are and what they do that would be great.
oh and i am no longer expecting to make 350 hp. more like i just wanna get to the 300 mark.

SpitotRs305

the vortec set up can make 400hp/400ft lbs @ the crank

but... not to sound rude or anything if you dont know what a cam is you shouldnt be touching that engine...

A cam short versions as the long version would take several years to fully explain...

the cam in a SBC is located directly above the crank and is what controls all valve timing the camshaft is made up of 16 lobes (and a possible eccentric lobe used on older engines with a mechanical fuel pump mounted to the block) when the cam is installed in a block the lobes align them selfs with 16 bores in the lifter valley each bore will hold a lifter of some type there are a few(solid flat,hydraulic flat,solid roller,hydraulic roller)the lifters job is to transfer the profile of the cam lobe to the rocker arm through the push rod so that the valve is opening and closing at the desired times... this precise timing is accomplished by gears connecting the cam and crank also know as a timing set and is a ratio the cam turns at half the speed of the crank

mattmerritt89

Yeah if you don't know what a cam is I would stay away from building youre own engine. But if you know someone that does get you a set of the HSR vortec heads a good cam. Get a dual plane intake intake youll make alot of youre power on the low end and a full exhaust system. I have a friend how has this setup and is making about 375-400 to the wheels.

InfernalVortex

iTrader: (4)

Do small things, learn, and then as you learn you'll be able to make yuor own decisions about what you want out of the car and how to get there.

I'll school you a little on cams.



That's a camshaft.



If you look past the crankshaft, you can barely see some of the nubs on the camshaft underneath it there.

The cam is what controls the valve timing and lift. The valve timing/lift is what determines your powerband. That's the range of RPMs taht your engine makes most of its power. If the valves are way open for a long time (a long percentage of the rotation of the motor) they flow a whole lot more air, but they run like crap at idle. (If you've ever heard a race car crackling and popping that's what you're hearing) That means you dont have much torque in the bottom end of the power band, but you make tons of torque at higher RPMs and (basically) torque times RPM = horsepower.

To make horsepower you need a cam that holds the valves open farther and longer. There are at least several hundred ifn ot thousands of cams for the sbc and each ahve different stats and specs to help you decide whether they'll work for you. You have to pick a cam that will match the rest of the parts you're using, and the rest of the parts you're using have to match each other too. This includes the intake, the induction, the heads, the torque converter, gears, and your compression ratio.

The key for a daily driver is you have to pick a cam small enough that the car is still drivable for commutes, but big enough that you can still have some fun with it and get to where you want to get. Generally you do that by getting a small cam and making the rest of the motor as efficient as possible. You want your intake, exhaust, and heads to flow as much as possible so that the cam is the bottleneck. That way you get the street manners you want, but it also still makes power. This also generally costs the most money.

Here's a quick rundown on numbers to look for when looking for a cam.

Duration (This is how long the valve is held open)
lift (this is how high the valve is opened)
Lobe Separation (This is complicated. If you stay EFI aim for 114. if you go carb, 110-114 will be fine.)

Duration is measured as total duration, and then duration at .050" lift. Pay attention to these. Duration at .050 is the big number you pay attention to. but you can get an idea of how good the cam is by subtracting the duration at .050 from the total duration. The smaller that number the faster the cam ramps up and the better street manners you get for a given amount of duration at .050.

.050 is a number chosen because basically the duration below that doesn't matter that much for power. At .050 things start to flow and you get an idea of how much time the valve is significantly open, therefore how much power you're going to make.

These are the measurements on what is priobably your stock cam:

Duration at .050: 179/194
Lift is .350/.384

That means the intake valve is open more than .050 inches for 179 degrees (out of 360 degrees of rotation) and the exhaust valve for 194 degrees of rotation. That's a tiny, crappy stock cam.

Aftermarket cams can improve the power over stock cams by opening the valve to higher lifts, or opening them for longer. Usually they go hand in hand. A good street cam will be around 210/210. A good street cam that will make some power will be around 230/230. Above that you get into cams that get a lot more impractical for daily driving. You start needing vacuum resevoirs and pumps and the car gets to be a pain in the behind to deal with and you also need a fairly high compression ratio to make it work. Really loose torque converters, and shorter gears in the rear end.

If you want to make it a drivable street car, aim for a cam in the 210-230 range on the intake and exhaust side. Your motor, if it's stock, is a roller motor, so you'll be pushing around .500-.550 lift for cams in that range most likely. Thats a big lift number so you'll make power. But you'll need new valve springs and you'll probably need some work done on your heads too.

It's not a matter of just bolting a part on the motor. You've got to get dirty and do some real work tearing things apart to make 350 hp to the wheels.

SpitotRs305

also
https://www.thirdgen.org/sbc-camshafts-primer

lots of useful stuff in that

89iroc-z559

thanks for all the help.
and you guys are right is shouldnt and will not be touching the engine. i will be buying the parts and have someone install them. thats i wanted to know if those where all the parts i needed to make the vortec setup work. will i need to get the vortec intake or does the stealth ram come with it? also is the hypertech chip anygood because i have been told i am gonna need a better chip but i dont know what to get. also thanks for all the info on cams. i kinda understood it i think. i wanted to know if someone could recomend wich one to go with. i do drive my car pretty often so it is gonna have to be realiable. i dont think ill go to the track to race because i dont even know if we have one in my area. so i basically want to just be able to beat some of the newer mustang and imports.
again thanks for all the usefull information i really appreaciate it.

SpitotRs305

you will need an intake specifically for vortec heads the stealthram might have the option i am not certain the hypertech chip would be a waste of money then again i think all mail order tuning is a waste as they will never be as good as a tune done actually being able to drive the car... as for the cam you will have to nail down your other parts first then we can help you pick what would get you as close to what you want

IE i know there are some tuners out there for LT1s and LS1/2 that will actually lend you a cable to datalog and you can then email him the logs and he can tune the car over the course of a week making corrections/adjustments with each new log... dont know how that would work with a 3rd gen as the hardware is a bit different but dont see why it couldnt be done

InfernalVortex

iTrader: (4)

If you're just gonna pay someone else to do the work, that's gonna escalate the costs tremendously. You'd get more bang for your buck and swapping in an LS1 at that point. Might even cost less if the LS1 is a running pull, since they wont need to tear it down like they will for what you have. The LS1 will hit your power goal too, easily.

You'll have a lot of money sunk into a Gen I build up when you can easily just go LS1 for similar amounts of money.

Guest

Wow you guys are talking like this is an impossible thing to do. Why? 350hp at the crank is only ~280 at the wheels and that is not that hard to do. You can get that far with the right cam, ported aluminum L98 heads, and the stock intake. I'll bet you could even get there on ported stock heads. If you were to want 350 at the wheels then yes its going to be more difficult and you'll be replacing most of the engine from the heads up but nobody ever said HP was free.

I might suggest though if you are going to build this thing yourself, read a lot, learn how motors work, post your combo here for advice before you buy anything, and don't expect to hit your goal the first time. If you do, great! If not, well... it happens.

InfernalVortex

iTrader: (4)

Nobody wants crank horsepower. They want wheel horsepower. 350 at the wheels is the upper limit of a what a reasonably-priced streetable combo can accomplish. You want 400 horses and you're gonna have to spend some major money or deal with a really lumpy cam or go for a power adder.

Unless you go 383... But I dont get the impression he wants to rebuild his motor.

Guest

There are a bunch of local guys here running smog legal 350's and putting down 350+. I put down 330 with partially blocked exhaust ports and stock runners. Nothing exotic unless aftermarket heads and base scare you.

InfernalVortex

iTrader: (4)

Aftermarket heads considerably increase the costs. That was the point of my original post... when you're spending $1500 on just heads and you're paying someone else to do all the work. removing, rebuilding, and reinstalling the engine and associated costs, I think you'd be a lot better off doing an LS swap.

If he could do the work himself I'd say aftermarket heads all the way. But if you're gonna pay all the labor to have all that removal and reinstallation work done, the difference in cost between a hopped up Gen I block and a running pull LS1 get a lot less significant, and the LS1 is gonna make just as much power and be far more streetable.

Saabster

iTrader: (2)

I love how this one gets spread around.

Guest

I agree about the LS1 having a lot more potential but he lives in Cali... even though its Porterville he may have to deal with the smog police and trust me that is no fun. It would be a lot less headache to do some bolt ons to a 350 rather than deal with the nickel and dime you broke LS1 swap. No dealing with frame notching for AC, special mounts, fabbing in the wiring, etc. He doesnt even know what a camshaft is, apparently, so... the last thing I would recommend is doing a LS1 swap. With some decent heads (I picked up a set of AFR's with very low mileage for $800), a used base (that I got for $250), and a basic engine rebuild I dont see his new goal of about 300hp being an issue and its not costly either if you are patient and choose the right parts. There are even some low priced heads besides AFR's that will do a lot better than factory stuff and get him close to if not past his goals.

SpitotRs305

i dont think people were trying to make it sound like a hard goal... because your right it isnt

i just didnt want to tell him to run out and get a set of heads, intake, fuel rails, cam easly over $1000 worth of parts without him understanding why he is buying the parts because i sure could rattle of a top end combo that would make right around 400HP and 400ftlbs @ the crank on a 350 all below 5700rpms

but thats not understanding that is being bossed around

Blackdog36

iTrader: (3)

89Iroc, I'm in a similar situation to you. Although I have another car for my daily driver, I recently bought a camaro. Tough part is that you want to start modifying the car right away. It's tough to accept but best thing would be to sit tight and learn. Your plans and goals for the car will most likely change the more you learn.

I have read as much info on this site as I could. Even though it's been a few months, I know way more than I thought I could. Many people have used the 350 and modified it for more power. There is a lot of good posts here and people are always willing to chime in on your questions.

You could get 300 HP to the wheels with some better flowing heads (like vortec), intake (TPIS large runners and big mouth base) and a little more aggressive cam. moving up to 350-400 HP you will need some really good flowing heads (like AFR). For this much power the stock rear end & transmission will need to be upgraded or replaced. 400+ HP will require a 383 stroker, new rear end, built up tranny and costs the most $$. As mentioned above you might be able to find some good used parts.

You can do some other things to help HP now and in the future with any upgrades. Full catback exhaust system with tubular headers and good tuneup. I bought this book that helped me a lot with understanding engines. It comes with a DVD showing engine rebuild process too.
http://www.amazon.com/Rebuild-Small-...2540591&sr=8-6

Keep us updated

Dustytrix

iTrader: (3)

I thought that was neat info on the camshaft Vortex. I got something out of it anyway.

kenny123

For that little power he wont need afr or a real expensive aftermarket heads if he doesnt have the money. I would just use a set of old double hump 202s. They are usually easy to find and will,(with the hsr and a cam) make that power just fine.

89iroc-z559

Wow. Thanks for all the input guys. Yea I'm not really planning on doing any of this soon. I'm just trying to ge ideas on what to do when the time comes. In the time being I'm gonna take your advice and just try to learn the most as possible before I take out the motor. By the way I just read about the FIRST tpi system and I was wondering your guys oppinion on it, it is more expensive than the stealth ram though. So is it worth it?

InfernalVortex

iTrader: (4)

I dont think those old dinosaur heads are gonna make any more power than the 083's he already has. He'd be better off getting his L98 heads redone for larger valves.

I still think the biggest bottleneck of a TPI car is the TPI.

Saabster

iTrader: (2)

A set of vortecs are always a nice upgrade as well. Double hump heads are old tech. They were amazing in the 60's, but we have better things today.

kenny123

haha dinosaur heads. That really is funny. but they really are great heads, and i know that in 2009 we have better heads. i was just saying they are an easy find and upgrade, they work just as well as any other 202 160 head, dont knock em just because they are older. some guys already said vortec and the vette heads, i was just making another suggestion. thats what the orig poster was looking for right? some suggestions

SpitotRs305

here is the engine i am running in my camaro although i dropped the CR from 10.5 to 9.5 not a whole lot of difference

Vortec heads 062 castings complete $400(junkyard special request)
only work was a deburr of the combustion chaimbers and a polish on the exhaust so i used a stock flow numbers heads were moddified for more lift although it was more of a rather be safe than sorry moment

and the XE274H10 a great cam for the vortecs plenty of vacuum has a noticably lopey idle but makes great midrange power

and summits RPM airgap knockoff stage 3,holley 700DP

mattmerritt89

They may be dinosaur heads, but if you don't have a ton of money they are great budget heads. You make pretty good horsepower, and you can upgrade them later when you have more cash. We had one on the dino we put 320 to the crank.

IROC UR WORLD

Here's my $0.02 worth. HP cost, but 350 hp doesn't have to break the bank. Here's a link that may be of interest to you. And others on a budget.

http://www.hotrod.com/techarticles/e...ild/index.html