I have an 87 lg4 (i think) carbed z28 with a 5 speed manual that im putting back together for my stepson. The engine needs to be redone, wile im at it I'm thinking of installing a 350 block with maybe vortec heads. I'm hoping to keep the changes to a min. so is there a combonation of 350 block and vortec heads that will allow all of the accessorys, intake and exh. to be reused?

thanks

 

Stock 1996-02 vortec heads can not, will not fit your intake.. They do make intakes to fit the vortec heads and your stock induction system.

All of your acc. brackets, pulleys, etc will fit onto most all gen 1 sbc block.

Your exhaust will fit most all stock type heads, even vortecs.

 

thank you Night rider327, is there an aftermarket/or stock intake that will allow me to reuse all the accessorys and the stock carb with the vortec heads?
again I'm looking for a setup to keep everything original other than the displacment and the heads. or are there other heads that i could use inplace of the vortec?

Thanks

 

Your welcome. Yes they make many aftermarket intakes to do that with.

If you will be reusing the Q jet carb you will need a spread bore intake, or a squarebore with spread bore adapter. If using a holley or edelbrock carb, they are square bore designs.

Here's the part #s for spreadbore dual plane vortec intakes on summit racing
EDL-2116
PFS-52007
PFS-52006

Those above will fit your stock carb, acc. bracket, water neck, etc, etc.

Here's the square bore vortec intakes (for holley/edelbrock carbs or use Q jet with adapter plate)
SUM-226018
WND-8121
SUM-226019
PFS-52028
EDL-2716
EDL-7116
EDL-7516

The vortec heads are the best bang for the buck, hands down. In fact they are the best production gen 1 sbc heads GM ever made. Vortec heads will gain you around 40 HP easy over other stock heads.

 

Night rider327 thank you for the help, I think I understand most of this but let me make sure.

I can replace the 305 block with a 350 and vortec heads buy the correct intake then reuse everything else just tune the carb to match the 350?

are there any other issues I need to know about?

thanks again

 

Yes:

Your stock LG4 exhaust is already The Bottleneck to your 305's performance. It becomes The Coffee-Stirrer-Neck to a 350.

Get rid of EVERY SINGLE PIECE from the heads to the street. Worst offender is the Y-pipe and I-pipe; too small for a 305. Next problem is the head pipes (the ones that hook to the manifolds); also too small for a 305. Problem with that is, the head pipe is the same size as the manifolds, meaning, to improve the head pipes, the manifolds gotta go too. Solution is, get rid of the ENTIRE 305 garbage, EVERY SINGLE PIECE from the heads to the bumper, and replace with a GOOD QUALITY set of headers (as opposed to, the cheeeeeeeeeeepest thing you can find that it's not illegal to print "headers" on the box) for a 350 in THIS SPECIFIC CHASSIS (NOT "universal"), such as for about a 88 350 TPI or something, which I HIGHLY recommend having ceramic coated; a good high-flow cat; and your choice of COMPLETE 3" cat-back (I personally prefer the Hooker one but there are others that are perfectly good too). You can install all of that yourself in a matter of minutes. Don't bother with muffler shops, "custom", "true duals", or any of the rest of the Friday night McDonalds parking lot monkey-spank you always hear about. Not only will none of that work any better, it will cost more than a set of headers, a cat, and a cat-back.

{copied & pasted from yesterday's answer to basically the same question}

 

sofakingdom thank you, I have a 2 post lift so the exhaust will be no problem. so 350 block vortec heads new intake along with headers to tailpipe.

are there any other issues I need to watch for, I'm good with the LS1 but the third gen is new to me.

Thanks again to all who have provided information.

 

Your welcome. Yeah you got it. It's a very basic swap.

Oh if doing the vortec heads, use Felpro MS98000T intake gasket set, I also recommend felpro 1094 head gaskets.

 

I wouldn't use cats unless you have to get the car inspected, my 86 has a 350 with headers going into 3.5 inch single exhaust ran like factory to a rear mounted single in dual out magnaflow muffler.

 

Use a cat.

Reason is, all that other stuff won't bolt up without one; it'll miss each other by about .... the length of a cat.

Modern ones don't hurt performance at all. And as CHEEEEEEEEEEP as they are, there's no alternative that's any cheeeeeeeeeper ANYWAY, so there's nothing to gain by not using one. All maze, no cheeeeze. Leftover anti-tech from the 70s.