Calaban007

My 89 IROC is smoking pretty bad. It desperately needs valve seals. Since I'm going to have to take the heads off and everything, I plan on just having the whole engine rebuilt from top to bottom.

So as everyone know this kind of project snowballs in a hurry. So now since it's going to be rebuilt I want to get some go fast goodies. I don't want a drag car, but something better than stock, maybe even close to my 95 Z28 when it was completely stock.

I'm going to do headers, cam, 1.6 RR, and possibly a new intake base. That's all I think will really need to be done besides a CHIP.

Any suggestions on the CAM, I want something with a decent idle, low to midrange since it will be a street car.

Well, any parts suggestions really. Bang for the buck is what I'm looking for. I don't mind spending the money on good stuff and having quality work done. Still, I like to see where my money's gone, you know?

Thanks a lot.

92RS(real slow)

your car looks identical to mine almost all l98s have valve seat problems its not that big of deal as long as it only does it on start up

Calaban007

Well it smokes on start up and if I rev a little it smokes. It's not like it's just burning off what's in the cylinder after it's sat all night. Then again I've only started it up twice since I changed the oil and spark plugs about a month ago to mow the grass. I need a shop to start working on the body.

BA92GTA

You don’t have to look very hard to make improvements to the feel and sound of the car.

Getting a lot more HP can be pricey and will likely take you away from a TPI set up and back to a carburetor. It is just the nature of the TPI and its airflow limitations.

I’m running a Comp Cam 08-422-8, with my TPI it’s a mild cam, sounds really good and gives a nice hole-shots “Low End”. Depending on what you want to do, you can go with a twin turbo set up or a nitrous injection system “NOS-05151NOS” along with the cam. It’s a hot set up, street and strip blast to drive.

I recommend a B&M shifter to enhance the street-strip experience. I added an exhaust cut out at the end of the y pipe. Yeah its loud, but when you have an import sitting next to you at a street light revving its engine with those coffee can muffler, pop the cut open and rattle his world a few times. They usually back off.

Dale

iTrader: (12)

I would install the vortec fastburn heads, and a new lower base intake. I read somewhere that it is a 60hp addon??

As for what cam, I'm just now entering the v8 world, so I dont know the specs on them. Just remember to buy for the intended use of the car. If your only driving it 2 times a month, I wouldnt waist my time n money on the bottom end, just replace the heads.

Abubaca

iTrader: (3)

Keep in mind that unless you're talking about the LT4 Hotcam, any cam conversation assumes you're running 1.5 rockers. The LT4 specs are assuming you're running 1.6. (don't know why, it's just GM for ya.) So, with that in mind, I can recommend the ZZ4 cam (with 1.5 rockers). It's a great mid to low cam, and it won't be to much for what you're talking about doing. With only cam, ignition and exhaust, my ZZ4 cam sounds great, idles perfectly with just a little lope, and EVEN PASSED EMISSIONS!!!! - All without a tune!!!!!!!! ...sure, you could gain a few ponies with a tune, but mine runs so well, I decided not to fix what wasn't broke!

.....anyhow, keep in mind that those 1.6 make any cam BIGGER, as far as valvetrain is concerned. If you're gonna do cam anyway, no need to spend money on new rockers. The stamped stockers are known to flex a little, so maybe just aftermarket 1.5s would help, but for a mild build, the stockers will work fine.

....also, with a bigger cam, you'll want new valvesprings and screw in studs. Your machinist will know what to use based on the cam specs you choose.

....you still runnin' the 700R4 in the Iroc? ...biggest bang for the buck would be a torque converter and a shift kit. I know, I know, it has nothing to do with the engine per se, but lemme tell ya! -After doing almost exactly what you're planning, I was pretty happy. I could tell a difference for sure, but it wasn't anything too drastic. Shortly thereafter, the 170,000 mile 700R4 blew up and I picked up a locally rebuilt tranny with a shift kit and a 2400 stall. D A M N!!!! What a difference!!!!!!! It was like a whole new car!!! ...just a little food for thought.

cronsformula350

Valveseats, don't cause the blowby problem, but the valve seals. But it's more the bad rings!

I have done a lot of work to my formula 350, one out of 25 made, lately, and it should be running by june 25th. Last night, I noticed there was a build sheet right behind the front end. I advanced the cam 4* today, it is supposed to make a ton more of torque, with the same hp, and I also put in the manual gear this weekend. The flaming river gear is what I put in, it's 2.5 turns from side to center to side.

I had 156K miles on my L98 motor in my iroc, and it broke the trans my third run, and ran a 14.86 at 86 mph, but mine never blew any oil. But if your always revving the motor, right after you start it, that makes the problem get worse. You could take the oil filter flange off, and tap the bypass, and plug it, then that should help a bit. But you could take it apart, and get some machine work done to freshen up the bottom end, with new bearings, you may need to undercut the crank, then if you can't buy new rods, have the stockers shot peened, that strengthens them quite a bit.

Use some new bearings. You can push L98 motors quite a bit, one has been pushed to 675 hp, as long when you get to the end of the track, you want to slowly rev the motor down, and that makes the rods and bottom end last longer, it sounds crazy, but it is what all guys with aluminum rods do, and rebuild it every 100 rods to be safe.

But the 700-r4, the gear spacing between first , second is huge, and I'm thinking about going to the 200-4r, it's still overdrive, and can take 800 hp. But if your making 600 hp, a 4L80E, is the overdrive version and updated electronic Turbo 400, that when built can take about 1200 hp, before you need some help.

For the 700-r4, I'm going to put a full, manual, reverse valve body in, because in time, this motor with two superchargers, on page 3 of my site, then you'll be able to understand why I want it.

Stalls make a huge difference, even with a stall, it can help, but the stock ones are only a 2:1 torque improvement, so yeah, more can be had. Any thing else, let me know, I have had a ton of knowledge of a lot of things, so. Just ask me. Check out page one of my site.

Calaban007

Thanks for the suggestions.

I'm going to talk to my Father-in-law's friend who builds race engines and stuff. I'll probably let him rebuild it. I know I want to get around 270-300hp at the flywheel. I'll probably just go with the mild cam, 1.5 RR, headers, chip, and a few other bolt ons.


I'll look into the Stall converter as well, but wouldn't that be more for a drag setup?

The shift kit sounds good.

Eventually I'll probably put some gears in it, maybe some 3.42's or something close.

I'll probably end up building one of the "ram air" setups behind the fog lights as well. I'm not going to race it or anything. I plan on just driving it occasionally during the spring and summer.

According to what I've read it came with around 230-245hp stock, so with cam, headers, and exhaust I might be tapping on 270-280hp.

What's your guesses on price? I figure at most 3k more that likely 2-2.5k if I pull the engine, which I probably will.

I'm not worried about he money, not that I'm loaded or anything, but I want it right and I'm not going to rush. I bought it with the intention of pretty much "restoring" it. As soon as I can get the interior out and surface rust off I'm going to sand, prime, and paint it. I'm going to do it myself. More or less just to get rid of all the surface rust. I used some rustoleum primer on it after I sanded the surface rust off and it was great for about a month but now I can see rust starting to form in the primer. After reading up on it, I found that primer wasn't a good thing to leave with out a coat of paint. So, I'm just going to sand it down again prime it and put a temp coat of white paint on it until I can get a proper paint job, but it will come after the engine and suspension. Interior will be last. I'm ready to get to work on it though. Wish I was loaded... it's going to be awesome.

cronsformula350

well I wrote this to another guys posts about questions regarding mods for a tpi, and there have been some that are stock short blocks and have gonge to 675 horses. But check this out:

Well with a HSR, and headers; you'll add about 100hp.

35 hp proven on the dyno, with one unported

25 hp with shorties and exhaust.

Spend the money and get the Comp Cams, Steel Pro Magnums, 1.6 ratio, they drop oil temps by 35*'s as proven by John Lingenfelter, get his book. And you'll add about 12 hp.

Then if you do a 160* thermo, that's 3 hp, a tb bypass, that's 3 hp gain but with a HSR, you don't need to do that, because you shouldn't have it on that manifold anyway.

Don't do a diff throttle body, the stocker is good enough for the 502 with fuel injection. I wouldn't get a bigger TB unless your running a 406 CI'er and running to 6500K, with a lot of improvements to make up the need for one. But the TPIS air foil can give you another 36 cfm of airflow, TPIS says is worth 11.8 hp. TPIS is the first make of an AIRFOIL too.

Also having a Adjustable Pressure Regulator, works great, they are definitelly worth the fifty bucks, get a gauge also. Higher pressure is worth about 10 hp, and 9 lb ft of torque. At the track if your having some traction trouble, off the line, you can turn the pressure up a little higher, and the motor will bog, just until your off the line.

Then if you do some sort of cold air induction, with K&n's, cut out the baffles from the factory, dual filter lid, where the dual snorkel goes too. Then where the MAF attaches to the lid, that spot that is a restriction to the air flow, hurts the efficiency. Also remove the MAF's screens, and also you could remove the FINS, but not if your going to drive the car a lot, but I did, for my formula. I did a lot of these mods, if you go to my page 8 on my site, you can learn that it all worked great.

Then you'll be all good. I have a lot of experience with these TPI's so, let me know if you have questions.

Abubaca

iTrader: (3)

40 hp gain is "possible", I might not go as far as probable though. But keep in mind those numbers are at the flywheel, not rearwheels, AND you've got a used motor.

Camaros had "cold air" from the factory. No need to anything crazy. It'd carry some cool points if ya do it right though.

All depends how big ya go. Anything under 3000 will still be real streatable. 2400 is 'bout perfect for a TPI. Plus it'll still lock up at highway cruisin' speeds so you won't have to worry about makin' trips.

That statement is like saying "put mustard and relish on your dinner". What are you eating????? Great if you're eatin' a hotdog, BAD if you're eating lobster. The comp pro mag 1.6 are a GREAT product, but if they go with the wrong cam, you completely mismatch your engine combo.

cronsformula350

well to that rockers combo, even if you go with, 1.5 ratio, you'll drop oil temps by 35*, but 1.6's on the stock cam, help make the cam a little bigger, and add some duration to it. Advance it 4*, add a stealth ram, holley intake, and some good exhaust, and that would be all you need.

You could, get the spark plug plug tool, to put air into the cylinder, and put new valve seals on it that way. Just get a tool, that will push the valve springs down, and then pull out the locks, and then the retainers, and you can put some new valve springs on the motor. It would be the rings though, if you start the motor, then immediately start revving it, that's no good.

The stock cam with 1.5 ratio rockers would be good for 10-12 hp, headers 25 hp for long tubes with more torque, but shorties still help drastically. And the exhaust could be good for 10 hp. But a dynomax muffler, and a dump before the axle is cheaper, and works great, go to my site, and see the pictures.

So that would be 45 horses conservatively, with those things, and the oil will be cooler. And if you spend around $650 on a Holley Stealth Ram, and that would be for the fuel line, and fittings, that will add 35 hp, I'd also recommend a TPIS airfoil, it adds 36 cfm. All these power #'s are conservative and proven.

Also for the lower intake dual air cleaner holder; remove the baffles, for making sure that no rain gets into the MAF sensor, that helps so much. And also that spot close to where the MAF sensor clamps on, that notch from the molding, Grind it down, and use GOOP to make up the space in it, it helps alot, you always want to make at least the intake as close to 100% efficient as possible.

Go to this page of my site, towards the bottom, and see for the stock TPI intake, what needs to be done to the Plenum, and what needs to be done, to remove the baffles.

These things will help, read what I did to my IROC-Z L98 motor, and what it did, that car had 4 wheel discs, 3.27 9-bolt those, but car craft said '87's couldn't have them, but mine did, and it was never changed. And the manual steering, removed a/c, headers, and all the other stuff, and after tuning, read it, and you can learn somethings, everyone can.