Ok, I've checked out all the information on this site about swapping a V8 into a V6 f-body. One thing that I've noticed is that some people say you will need to swap the cat & cat back exhaust when making the switch others make no mention of it.

What I would like to know is if you HAVE to swap out the exhaust system along with the motor/trans? I just put a new exhaust on my car (a little over 1yr ago) and can't afford to do it again.

If the exhaust has to be changed then I guess I'm putting the V6 back in

TIA,
Don

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Black 87 2.8l Camaro

http://photos.yahoo.com/bc/z2point8l?d&.flabel=fld1&.src=ph

Aka Z2point8

 

Without a doubt the stock cat for a V6 will be too small for a V8. But, if you have at least a 2" to 2-1/2" cat & catback, they will support a 305 (depends upon how healthy the 305 is).

The way I put it when discussing the V6 to V8 swap parts-needed topic is "exhaust from the heads to the rear bumper". If you replaced your exhaust with stock-size parts, figure on needing to replace them.

FWIW, between Summit & JC Whitney, my exhaust is costing me around $575. That includes 1-5/8" primary headers, 3" y-pipe, 3" cat and catback to 2-1/2" dual tailpipes.

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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R4. 2.93 limited slip. 2-1/2" cat-back, ZZ3 intake, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LG4 CC system w/'87 LB9 block, ZZ3 cam, ported World 305 heads, Hooker 2055 headers, 3" Catco cat & 3" catback, restalled TC, Spohn SFCs).
57 Bel Air, my 1st car. '66 396, 9.7 CR forged TRWs, Weiand Action+, Holley 750VS w/4150 conversion, GK 270 cam, Magnum rockers, Jacobs Omnipack, 1-3/4" Hedders & 3" Warlocks, TH400 w/TCI Sat Night Special conv & Trans-Scat shift kit, MegaShifter, 3.08 8.2" 10-bolt w/Powertrax, AMSOIL syn lubes bumper-to-bumper. Idles smooth @ 600 RPM in D. Best 15.02/95.06 @ 5800' Bandimere (corrected 13.93/102.4 @ sea level).

[This message has been edited by five7kid (edited September 13, 2001).]

 

Thanks,

My exhaust system is a Walker free-flow cat with a Carline Free-flow muffler. All the inlets/outlets are 2 1/4". Total cost was about the same (but in CDN$, Installed)

 

That will do, but will be restrictive for anything more than LG4-type power.

You'll need a V8 y-pipe, of course.

 

How do I know if the 5.0 I have is infact an LG4? All I Know is that it came from an '83 and that it was an H.O engine.

 

CanadianCamaro,

If you're interested I've got a complete brand new exhaust system in my garage minus the CAT for a V8. Hooker SuperComp shorty headers, 3" Y-pipe, Flowmaster 3" CAT back with 2-chamber muffler and dual polished 3" outlets with ***** cut tips. I bought it before I got the big block and I can't use it any more. I live in south-eastern Washington. It's not cheap but it will save you about $120 if you want a good exhaust system.

 

Well, that's an interesting edit... s-l-a-n-t cut tips.

 

Thanks QwkTrip, but at this time I don't have the $. Gotta get a second job this 16hrs a week is B.S.

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Black 87 2.8l Camaro
Soon to be 305/5.0

http://photos.yahoo.com/bc/z2point8l...l=fld1&.src=ph

Aka Z2point8

[This message has been edited by CanadianCamaro (edited September 15, 2001).]

 

If truly an HO, then it is an L69. If possible, get the exhaust off of it - it'll be better than your V6 exhaust.

 

I would but the car is long gone The engine has been sitting out of the car for atleast 4 years, did a compression test & everything seems to be ok

Is there a vin # or something on the block that I use to see if it's an LG4 or L69?

[This message has been edited by CanadianCamaro (edited September 17, 2001).]

 

My LG4 has "LG4" stamped either on the block or the intake manifold, I dont remember which.

Mike

 

An LG4 will have an "H" in the VIN. I forget what the L69 has.

 

http://www.mortec.com/castnum.htm if you have the id numbers go to this site and it will tell you pretty much everything to do with the motor you have in your hands