CamaroStylin

Hey everyone. I currently have an 88 base model camaro that I use as a daily driver. Of course, it's got the little 2.8 litre engine, which wouldn't be that bad if it wasn't in a 4000 pound car. I'd like to build up an L98 (350 TPI) and drop it in there and would hope to get about 400hp at the rear wheels, if not more.
Ive torn down and re-assembled engines before, but I've never highly modified one. The reason I want so much power is because I want this car to perform to similar standards as set by the corvette Z06. For a first timer, this is pretty hard without some serious component information from more experienced builders. so here we go

Anyone who can help me out with reaching this goal would be a saint in my book. All I require is tips and suggestions on how to build this monster 350. I want to stay away from forced induction because the small block chevy can only hold so much pressure, and the vortech supercharger only gives a 35% increase in power. I'll be balancing the rotating assembly, installing 1.6:1 rocker arms, stronger valve springs, true roller timing chain and some ignition work using MSD products. aside from those definates, I dont know where to begin. Anyone know of any strong setups for this engine? I've already ordered John Lingenfelter's "Modifying a Small Block Chevy," which I am told has a setup for the L98 that claims 442hp.

this will still be a daily driver, so optimizing the engine for wide open throttle is not an option, although i know many performance builders like to do that. Smooth idle is of course not a high priority at all. I cant expect that kind of power from an engine that idles like an accord.

anyway, i just need someone to point me in the right direction here. FYI, I do have a fully functional copy of Desktop Dyno 2000 on my computer, so actual performance levels can be measured given a suggestion from anyone who isn't exactly sure what to expect from whatever setup they have in mind. so please, speak up!

thanks!

ZWILD1

Not to brag on myself too much, but I've owned 5 '88 IROC's (don't ask why!). As for TPI, my feeling is that it is the best truck motor Chevy ever built. Too bad they never installed them in trucks, but from personal experience: trucks love TPI. If you have no problem going to a non-TPI setup, there are a number of ways to get to 450 efi ponies. They range from cheap (StealthRam) to absurdly expensive (MiniRam). So my first question would be: how much do you want to spend?

Secondly, I would suggest finding a beater 5.7 car. It will be easier swapping parts you wish to keep from your RS to that car, than it will be to convert a v-6 car to v-8.

Finally; as regards using a Vortech blower: their TPI kit will bring a 230 hp 5.7 TPI up to 330 hp. That equals a 43% gain, and when added to a 300 hp TPI (fairly easy to attain) it equals a capable Z06 hunter. No it won't be quite as fast as the Vette, handle as well or look as good, but no one will write you off as a poseur.

Steve in Seattle

I don't have much to add beyond what's available in Lingenfelter's book. While it hints at LT1's a few times, and really discusses L98 heads at length from time to time, the heart of the book is geared for the SBC in general. You won't be disappointed.


The one item you may want to address before the engine is the rest of the drivetrain. I really doubt the RS's rearend will be abel to hold the power from a built-up L98. Their as bad a 4th gens, except they have even FEWER splines. You'll want a bigger rear with a posi or torsen unit for starters... then look for a tranny.

I'm sure the 4th gens 4L60E and T56, or even the C4's ZF 6-speed will hold up fine, I don't know much about the 3rd gen trannies other than the 700 was good enough fo GM to put them behind L98's. But the T5? well.... it's a T5.

I belive D&D Performance has a kit for adapting a T56 to 3rd gen camaros if you decide to row the gears yourself.

ZWILD1

As regards L98 heads, give them a pass. By the time you've spent enough where they flow like Iron Eagles, you could have just bought Iron Eagles.

If you decide to start with a v-8 car, here's some tips:

if it's a 5.0L (LB9 TPI or LO3 TBI) look for the G92 option code under the console lid. on an '88 or '89, G92 gets you:
-9-bolt, 7.75" rear-end (arguably the stongest factory rear-end in third or fourthgens)
-posi
-rear discs
-engine oil cooler

- if it's a 5.7L (BL2 TPI), the G92 option was mandatory-standard
- to confirm it is a 5.7 car, look for an '8' as the eighth digit in the VIN or 'BL2' is one of the three-digit option codes under the console lid. '88 and '89 were the most popular years (saleswise) for the 5.7L engine and they're generally cheaper than the '90-'92 cars.

- take a pass on anything advertised as 1LE. these cars are rare (8 built in '88, 111 in '89). they command a substantial price-premium for the authentic ones, and there is an increasing number of faked ones being sold (i.e., I recently saw one on eBay that was advertised as a 1LE with a race-history, 5.7L/5-sp. -that engine/trans combo was never available- and worse yet, the engine pic showed factory a/c -a/c was deleted on 1LE's-).

Fast Caddie

Well since you have a traditionally cooled SBC and want BIG power, why not look into some of the more radical heads offered out there? One project i've been contemplating is getting an L98 and punching it out to as many CI as it'll take (can a L98 go to 400+CI? I think i've heard of a 406 L98 before), then getting the Brodix 18 STD X heads and putting them on top. The 18X is an 18* head with the 23* valvetrain and standard SBC exhaust(very good when trying to find headers). They advertise that it doesn't require offest lifters, but i think it will need offset rockers. 245cc intake ports and flows over 300CFM right out of the box, so it'll be a radical head on a regular disp small block. That's why i wanted as many CI as possible to tame them a little. As far as intake.... either modify a HSR, LT4, or rework the carb manifold(Brodix, HV 1800 or HV 1801) for EFI use. The heads themselves are close to $2200 a pair, but that's assembled with springs good to over .600 lift, titanium retainers, and around a 2.15 intake valve. This is the way to make HUGE power NA

If you just want to get something like 400rwhp without too much of a hassle, various bolt-on and power-adder combos will get you there. Porting the lower plenum, adding larger runners, ZWILD1's suggestion of dart heads, a good blower cam, and that Vortec kit should do well more than 400rwhp. Or save the money on the intake mods and switch to a HSR or LT1 intake then boost it.

Just some things to think about

SStrokerAce

Before we go getting into big heads and motors, what kind of money do you have? That's always the #1 limit for building anything up.

Anyways a L98 is a traditonal SBC so any SBC part goes right into it. The cheapest way is to get a 400+hp crate motor and drop EFI on it. I think GM has a 383 with Fastbrun heads and with a decent intake that thing should make 450-500hp for you.

There are a TON of great parts out there for what you are looking to do.

Bret

Injuneer

This would appear to be an appropriate post for "3rd Gen Tech". Moving it there........

ZWILD1

I'm a little biased towards the Iron Eagles, because I've used them on two L98 rebuilds and got very good results. Flow-wise, the 180cc IE's as-cast intake flow is better than 180cc AFR's as-cast. Where the AFR's shine is on exhaust flow and chamber design. Still, for the money you'll save over AFR's, you could pay someone to work the exhaust ports on the IE's (not much you can do to improve the IE's modified-wedge chambers without spending big bucks).

Z28SORR

Posted this once before as an example.

401wrhp. ZZ4 350 short block, reworked L98 aluminum heads(bigger valves, 5 angle valve job, pocket port and port match), LT4 hot cam kit(1.6 rockers), 58mm throttle body, 24lb/hr injectors, adjustible fuel pressure regulator, High performance fuel pump(in tank), CAI, LPE/edelbrock superram air intake, Borla cat back w/high flow cat, and of course programming. Over $5,000.
But all was new so it could be done for less.
Also I would not do this combo today, better parts out there now!

This engine had excelllent idle, mileage, and was emissions compliant. I originally intended to do this with the 385 fast burn heads, but no TPI base was available at that time. It is now!!

BOZS89IROC

It's actually not to hard or expensive (depending on what you consider expensive) to get 400 h.p. out of an L98. Alot of people dont like them or think that carbs are the way to go. It all depends on what you want. If your not looking for a drag car but you want a high performance street, daily driver than by far TPI (or at least F/I) is the way to go. If you are looking to make alot of h.p. quick, cheap, and easy then carb it. TPI is the most popular F/I system for a reason. If the ability to make decent torque and/or h.p. and still find the car streetable and getting decent gas mileage with minimal emissions is what you want then here are some things you can do.

Siamesed air runners
Big mouth plenum
Big mouth intake
keep the stock injectors
adjustable fuel press. reg. (adjust f/p to no more than 55 psi)
longer duration cam (roller cam and lifters if already doesn't have it)
58mm throttle body
if it's MAF remove screens and/or buy ported MAF sensor
headers
high flow cat
recalibrate ecm, chip ecm

also, you could add a LT1 intake, the shorter runners give you a little more h.p. but slightly reduces torque capabilities.

Machine services to be considered:

port & polish heads (if using stock heads)
port match intake to heads
bore and stroke (377-383) (would need new crank and/or conn. rods...can get expensive.)
3 angle valve job
good choice to have the block magnafluxed, hot tanked, and honed.

This is all worth much more than 400 h.p. but remember you can't just throw parts onto a TPI and expect them to work well together. You need to shop around and ask the manufacturers questions about compatability.

Good luck

-Boz

trackbird

Your goals are reasonable.

You'll need fuel, so an upgraded pump is in order.

Your going to need air. The factory mass air is a restriction at that power level and there are few choices for much else to use as a properly sized MAF. I'd suggest a custom tuned prom from Ed Wright or TPIS and a speed density EFI computer.

For induction, you'll need something with shorter runners. A Holley Stealth Ram should be capable of doing what you ask, or the TPIS mini ram (while putting a larger dent in the checkbook).

Cam selection will be something on the order of a hydraulic roller with a duration of at least 220 degrees at .050 (crane has a 220/230 with a .510/.520 lift as I remember) that may work well, or a grind from TPIS can do what you require as well.

Heads are key (other than a high flowing intake) for a high power TPI motor. You may consider the AFR aluminum heads in the 190-195 cc range (verify that they will mate with your chosen manifold). Or, Edelbrock Performer RPM heads are a decent choice for less $$$ (they will probably cost you in the HP department slightly though).

Have the bottom end balanced and assembled with good rods, pistons, rings, bearings, etc and set it up for about 10.5:1 compression (still pump gas friendly). Have the machine shop "0 deck" the block to help avoid detonation. At this power level, a good crank and rods will assure a long, healthy life.

Exhaust will need to be headers and a free flowing exhaust system. You may do ok with the 1 3/4 inch tube SLP headers, but you would be better off with 1 3/4 inch hooker super comp headers. This will require some type of fabricated exhaust and may be difficult to tuck under the car.

Those ideas should get you started. I'm sure others will have stuff to add to that list.

Have fun and good luck!

My thoughts....

AutoRoc

If you're not exactly sure on how to go about modifying an engine, and are concerned that you may make a mistake somewhere, paying a professional is theee way to go. Listening to numerous opinions on "what might" make good power is a lot different than hearing about actual results.

I'm not sure why I've been promoting crate engines lately, maybe it's just because it's such a craze right now. Time, Money, and Stress can be saves by just buying a 100% built/tuned/dyno'd engine from one of the many reputable builders out there.

You want ZO6 comparable or better power I see and that seems to be the only goal and you want it to be moderately tame in traffic. $10,000 can get you pretty much any engine you want and it will make pretty much any amount of power you want(under 650hp for small blocks and under 850hp for big blocks ROUGHLY..). Bill Mitchell Harcore Race Parts sells 415, 427, 454 cube small blocks that can make from 450-600+hp. Their 454 makes over 600hp and a LOT of torque for about 10 grand all while running on premium pump gas and sporting a warranty even.. With good traction in your "4000"lb car and normal gearing, that's EASILY an 11 second car and it would lay waste to any stock motor ZO6 Vette. If you wanted more, Nitrous Oxide is always fun. Swapping to a big block could get you into the 700-800hp range but you would need other special parts like headers that won't be a problem, maybe new springs up front...just little stuff like that. GM sells awesome crate engines, Edelbrock sells VERY tame mills that make 400+hp. BES and BRE both make aggressive street engines. Buying an LS6 engine just like the ZO6 has would be cool also! Gm readily sells them. If you want more than that, MTI and ARE in Canada build MONSTER 420+ cube LS1 and LS6 engines and they're more than willing to let one go to you for a reasonable sum...hehe Goodluck!

ZWILD1

It's actually not to hard or expensive (depending on what you consider expensive) to get 400 h.p. out of an L98.

Having played with a few L98's and having spoken to quite a few folks who've done the same, I can confidently say that it is neither easy nor inexpensive to get an L98 to 400 rwhp. You can spend $1500+ on "Big Mouth" this and "Siamesed" that and not reach 375 hp. Or you can spend under $1k for a StealthRam or Performer EFI setup (using the stock ecm) and get equal or better results.

And despite what many folks may think, the stock intake components are not the most restrictive elements of TPI motors. That honor is shared by the heads and cams that came from the factory. Once you've got decent heads and valvetrain, you need to plan on spinning near 5500 rpm to get 400 rwhp from a 350. And that's beyond the capacity of TPI - even with the "Big Mouth" and siamesed parts.

keep the stock injectors
The stock 22 lb injectors are only good to about 450 fwhp, assuming an 85% duty cycle and assuming they are ALL in very good shape. Work them that hard for any length of time and you WILL run into problems. At the hp levels we're talknig about here, consider a minimum of new 24 lb injectors.

adjustable fuel press. reg. (adjust f/p to no more than 55 psi)
Good idea in principle, but not a good substitute for properly sized injectors. Bosch-style injectors are calibrated for 43 psi. Up the pressure more than 10% and you will start having problems with poor spray distribution and pintle seating and fluttering. 55 psi will drastically shorten the life of the injectors and they'll need to be replaced or rebuilt. Do it right the first time and save some money.

longer duration cam (roller cam and lifters if already doesn't have it)
EFI (especially TPI) gets harder to tune as overlap increases. Focus on LSA's of not less than 112° if you insist on TPI, or 110° if you are going with a shorter runner setup. Durations of up to 224° (@ 0.050" valve lift) work best with a near-stock TPI intake). Short runner manifolds seem to like 230° or more duration.

58mm throttle body
Bit of overkill. The stock 48 mm TB will support over 500 hp and 550 lbs/ft (Ramjet 502). Upping the TB bores will net relatively small gains while gradually diminishing throttle response. Buying a $50 TB air diffuser will gain as much hp as a $400 54 mm TB. If you foresee more than 500 hp or plan on going north of 6000 rpm on a regular basis, I can see getting a larger TB. Otherwise, there's better places to spend your money.

if it's MAF remove screens and/or buy ported MAF sensor
Factory Bosch MAF's are now 15 years old, so it wouldn't hurt to replace it, if you've got one. The ported MAF's are nothing more than reworked factory MAF's and need recalibrated MAF tables in the EEPROM to work properly. On the other hand, you could buy a new Wells MAF (about $150, use the money you saved from not buying an oversized TB ), which flows more with it's screens intact than the ported MAF, is more durable (thin film vs thin wire) and is calibrated for the factory MAF tables which almost all chip-burners use.

aklim

An LPE 383 will do nicely. You will shred the tranny and break rear end gears unless you rebuild the tranny right and have some sort of support girdle for the rear end.

CamaroStylin

thanks for all the info you guys. there's a lot of great stuff here. I feel like there's so much information that I've got more questions now than I did before, but hey, maybe that's good. Ive heard things on this thread ranging from "TPI is perfect" to "TPI is incapable" and dont really know what to think of all that. I find it hard to believe that a 350 with a fairly efficient fuel injection system could not produce this kind of power, so I'm going to stick with the TPI system. I do appreciate the info about the stock intake. Ive had many people tell me that it needs to be replaced, but I've always thought of it as being plenty large for the air flow that i require.

It seems most of the power would be comming from the heads, from what I've read today. is this correct?

It has been said that I'm using a "traditional SBC" and that any parts should bolt right on, which is what i've always thought to be true, but it seems that all the parts i look for now are for engines "up to 1986." whats up with that? all the rebuilt kits say the same thing, and the stroker kits ive been looking at. The heads also often say they cant fit on 86 and newer 350s. I dont quite understand what the difference is.

is it possible to buy a 450hp (just an example) "long block" and then just slap on a factory TPI system with aftermarket MAF and injectors (and fuel pump and reg) and get the performance I'm hoping for?

to save time, money and frustration, i'll be keeping the 700R4 setup, but I will be taking one to a transmission shop to have them "beef it up" a bit to hold this power. is the 700R4 computer controlled at all? what im getting at is, will it become a problem trying to get an a modified 700R4 to work with the camaro's stock ECU?

what all is involved in turning a carbed engine to F.I.? just swaping the manifold and intake system and fuel rail and what not? plus the ECU and harness and everything. that's a given.

thanks for all the support guys! just so you know, the v-6 camaro already has a tortion (sp?) bar from the tranny to the rear end, and I will be switching to posi traction before putting in this engine. thanks for the warning though.

I read also read that the 350 TPI came with rear disc brakes. I didnt know that... the only 3rd gen i knew for sure came with the rear disc brakes was the limited edition firebirds. do you guys think it would be more cost efficient to buy a disc brake conversion kit? i mean finding a car with all this stuff on it would be near impossible, especially for a good price!

thanks again for all the help. keep it comming!