I bought an 88 Formula a while back with a blown 305 TBI. I planned to rebuild a 305 for it since it will be a daily driver, but after seeing the GM Goodwrench 350 crate engines for about what a decent rebuild on the 305 would cost, I'm thinking about going 350 TBI. Would it be better to use the 2-piece rear main older style engine for about $1300 or the B-body(Caprice) engine for $1500? Does the Caprice engine use the junk swirl port heads? It sounds like the better buy with the roller cam and the ability to use the stock intake manifold. Besides a 350 knock sensor and a bump in fuel pressure, what would be needed to make the engine run properly? I'm definately keeping the TBI.

 

Gentlemen, I'd love to get the details on a swap from the 305 to 350 while keeping the tbi set-up. However, I really want it done "right" with no dependability problems. If it can be done, my 89 Formula would get the 350. If there's any doubt about reliability and computer hassles though, I guess the 305 stays but in a "warmed-up" state.

 

formula, the lo5 caprice has swirlport heads.
YOu could buy that engine, and probably trade or sell the heads and then get a better set of rebuilt locally. I was going to do that and they would have given me
$200 trade for a set of 285 HP heads so the net cost would have been about
$300. Not a bad way to go but you will also want to get rid of the lo5 cam too cause it is pretty weak.There is a lot of stuff on this in the archives so check it out.
YOu should add a 350 ESC module, 65# injectors and get a cop chip from a B body that will fit your ECM. I don't know what
the 88 ECM is but the 89 B body ecm is the same as my 91 f-body and so I could use the cop chip. Once again a few hours in the archives will really help you out.....bob


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91 camaro RS convert,GM crate 350 with LT1 cam,edelbrock 6085 heads,9.5:1 comp, edelbrock TBI intake, 65# injectors, GM cop chip,dual fan conversion,
ultimate TBI mods,TBI spacer,SLP 1 5/8 headers,
3"cat back,Flowmaster,
T-5, centerforce 2 clutch, 3.42 torsen posi,alston SFC's,Global West LCA relocation brackets, edelbrock STB

 

you may want to look for any post by jprevost. we did his engine swap and kept the TBI set up completely intact. he has all the details on his web site.

lata
tim

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91 Camaro RS-LO3,Auto.
14.209@95.46mph
Best 60' 1.917
Check Out The East Coast F-Body Nationals Home Page
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My MAFB.ORG Home Page
www.mycar.net/mafb/registry/detail.cfm?id=299

DSI Racing Home Page
www.geocities.com/foff667

 

yes the heads are junk. get the Lo5 shortblock ($1100) and put some non swirl port 350 TBI heads on it from www.sdpc2000.com and put a LT4 cam in it. Or some 23* Trick flow heads for $850.

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-Tas
'89 Formula WS-6

305, TBI, auto, 14x3 chrome flat based open element with K&N, Milodon 160* thermo, functional Formula hood, cross-flow Flowmaster, '99z28 rear pipes and tips....

Soon to be installed:
Hooker 1-5/8" 50 state legal headers, Dynomax 3" I pipe (PN 44063 and 43248), Catco 3" cat, and injector spacer.

Super GRK_Taz World
F-Body Dual Exaust
EFI & Intake Options
AOL IM: superGRtaz

 

I know everybody likes to bad mouth the swirl port heads but they really aren't that bad. I flow checked a pair stock, 178 cfm on the intakes 144 on the exhaust.

I did a little clean up on the intake bowls and ported the exhaust completely, then they flowed 196 on the intakes 186 on the exhaust.

This produced a solid 40 hp gain at the rear wheels. Not too bad for a junk set of heads with just a little time invested.



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Chronologically challenged. But still kicking!
'92 CAMARO RS
305 TBI 5/spd (now TPI)
B4C Alt.
'69 camaro-BB/Lenco,1050 dominators, /Pump Gas/no drugs 8.97-150+/3200lbs.
SoCal Thirdgen F-Bodies

 

There are several of us on this board who did this swap, just look through the back pages. I purchased the L31 short block from SDPC for $1199. It has four bolt mains, one piece rear seal, made for roller cams, same block, same rods as ZZ4 engine. Vortec heads with upgraded springs, LT4 cam, 1.6 Crane roller rockers, Edel intake, 670 Holley with 65lb injectors. Started with 89 cop car chip ANLU. It cranks great every time, cruises great has great torque, but just starting to tune the chip this week which it will need. There is not a stock chip for you to use, only one that will get you started on the particular combo that you come up with. Hope this helps.

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91 RS 350TBI VORTEC HEADS EDELBROCK PERFORMER INTAKE LT4 CAM AND 1.6 ROLLERS EDELBROCK HEADERS 3' EXHAUST 5SPD 3.08 GEARS

 

Dyno don, I heard similar flow numbers
from a local machine shop here in Denver.
I didn't believe them and thought that they would actually flow less than that. Given
those numbers, the stock lo5 is a good deal for the money. Sounds like with the head work
and a cam that engine would be good for 250-275 hp. Not bad for a $1500 bolt in.......bob

 

Gentlemen thanks for the information. Next question: Why not use the L98 shortblock and just build a nice set-up from there? I'm assuming that the L98 block is set up for a roller cam. Also, a nice set of AFR heads could top things off. My main concern is the computer compatibility with the swap. And then there's that "legal" question regarding emissions (I'm in California). I'm not shooting for monster hp/torque #'s with this set-up. An honest 300 hp would be nice (and practical). Comments?

 

Thanks for the replies, but what I'm wanting to do is basically a stock 350 TBI as if it came from the factory that way. I have a GMC pickup with a 350 TBI, and would be very happy with that performance in the Formula. Has anyone used the 69-85 Goodwrench engine in a TBI car? Can the stock TBI intake manifold be modified to work with the older style heads? I want to buy a crate engine and drop it in untouched. I'm not interested in a high performance combo, but if I can buy a 350 for what a 305 rebuild would cost, then it makes sense to go with the 350. Are ECM changes needed for a stock 350? I think the Caprice crate engine would be a better swap. Sounds like the swirl port heads would work pretty well for what I'm doing.

 

Rsilver, you're in Denver?
Did I read it right that you have the 350 TBI? I was planning on doing that for my car with the GMPP 350 crate, but everyone told me I would fail emissions everytime. Are you going to fail? It got so bad that I wanted to throw a supercharger on my 305 instead, but it turns out that it actually costs more to do that, and I'd be 100 hp short of what I really want.
Let me know, cuz I don't want to fail. Also, did you get it done? I need to find a shop that will do it because I'll f it up.

 

88 Formula I wish you lived close by. I would let you drive my 350 TBI truck and then make you a good deal on it. It has 87k miles on the shortblock. I had the L05 heads shaved, ported, 2.02 stainless intake and 1.6 exhaust valves, 3/8" screw in studs and guide plates, 110# valve springs with 1.6 ratio roller tip rockers. I run a Crane Compucam 2050 with double roller timing chain. Also put in a high pressure oil pump while I was doing the heads. I would like to get $1100 for the motor which is what I have in extras I did to the motor. Truck is really fast for a truck (a lot faster than my Camaro) and gets gas mileage within a couple MPG of stock. So you can get good performance out of an L05 especially in a car that weighs 1000 lbs less than my truck.

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91 Camaro RS 5.0L Black Convertible 700R4
** Added so far **
*GM Wonderbar
*Alston SFC's
*Turbo City Inj Spacer
*Dual Snorkel Air Filter
*March Performance Pulleys
*GM 3.42 Gears with OEM Zexel
*Edelbrock headers
*3" High Flow Cat
*3" Dynomax Exhaust
*Walbro 255 lph Fuel Pump
***Future 330hp Vortec Crate with LT4 hotcam and 454 TBI

[This message has been edited by brharris27370 (edited June 26, 2001).]

 

That's easy. Get caprice parts. Get the caprice engine from GM, get an '89 caprice 350 chip it will work in our ECM's, get the caprice injectors, get the caprice knock sensor, and you will have it, our intakes and TBI unit's are the same as the 350's, the only other difference might be the exhaust. I probably missed some biggie, but I'm sure someone will catch it if I did.

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1989 Pontiac Firebird Formula LO3 Auto
-180 degree stat
-Hooker Cat-Back
-velcro t-top bag
-Wonder Bar from my IROC
IAT MOD, 3.3ohm resistor

*****Possible future mods*****
4th gen seats, fiberglass spoiler, new paint

1985 IROC-Z, TPI Auto
-Accel Super Coil
engine and tranny overhauls coming this summer


http://www.geocities.com/krt80/

 

Pullmeover, yeah I am 100% emissions legal.
I checked with the state level emissions guys before i did the swap and they said I was ok as long as I ran an EGR and the smog pump cat etc.
There are a number of guys who have passed without the egr, but if they do a visual they will fail. the trick is to use egr heads/manifold which does limit you but still can provide decent performance. You can also use the vortech heads with the EGR manifold but you will have to do a lot of plumbing to the headers or exhaust manifold to make it work.
I chose the edelbrock heads cause they were egr heads and my swap was a 100% bolt in with no hassles. I did it with a friend who is a long time chev Gm tech but my role was mainly gofer stuff and staying out of his way.i would recommend him but he did it as a favor and rarely does it for others.
E-mail me if you have questions...........bob