I'm rebuilding my 305 LB9 right now and was looking to see if you guys had any tips to get more out of it. I've already added a few minor things (as listed below), but was looking for a few more ideas within a decent range. Sure, I wouldn't mind dropping a 427 in it, but that much money is out of the question right now (but definitely in the future though). I've ran it a few times and watched a few 5.7's and Mustangs gain distance in the rear view, but I'd like a little more to play with until time comes for the BBC.

 

Vortec heads, intake (remember its gotta be compatible with the Vortec style head bolt pattern), headers, and some other things like wires, cap and rotor kit, maybe a HEI conversion, and if youre up for it, a cam.
Dont forget the free mods like taking A/C and emissions out or gutting the cat.

 

In Arizona, A/C is a necessity. I'd remove all the smog s***, but it's required for emissions. I gutted the cat, but had to buy a High Flow to replace it since the car wouldn't pass without it. I've got an MSD HEI module and coil, MSD wires and Bosch Platinum 4+ plugs. I was planning on installing a Comp 2040 cam since everyone here seems to be pleased with them. Vortec heads and a new intake is a little more money than I have right now. Thanks for the advice and any more ideas are welcome.

 

Vortecs on a 305 TPI borders on silly. You need that expensive SDPC Vortec base, you'll have to shave the heads to maintain compression, the valve springs that come with the heads are pure junk, you need self-aligning rockers and centerbolt valve covers (which your '86 doesn't have), you'll have to rig up some way to plumb exhaust up to the base for the EGR valve, and on and on it goes.

If you haven't already, port your plenum (there's a tech article on it IIRC, if not ask the guys on the TPI forum). You can get a lot out of your stock TPI heads by doing a simple porting job (follow the instructions that come in the Standard Abrasives Deluxe Porting Kit, ~$40 from Summit or Jegs). For a little more money, have 1.94" intake valves put in the heads. Those mods would complement an upgrade cam nicely. I'm not familiar with the specs on that cam, but stock runners limit RPMs to about 5000, so the cam shouldn't make power above the range of the runners (unless you spring for aftermarket shorter runners).

Exhaust is another key to making power. Your TPI system is the best they did with single cat, but headers would improve it even more. High flow cat and cat-back would top it off.

 

Thanks for the advice five7kid. As you can see I've added a few things, but really didn't want to get into changing heads or anything major. Changing the cam is no big deal since I've already got the motor out and it wasn't that expensive. Intake valves aren't that much and the porting kit is cheap (wish I new about it sooner). The headers are a little out of reach for now, but if there's anything else that comes to mind let me know. Thanks again!!


Also, I've got to replace the torque converter. Any suggestions?

 

Get a high-flow direct fit from Catco, Random Tech, Dynomax, etc. That's the hot ticket for any single-cat, high-performance exhaust set-up, and you've already got the right factory start.

If headers aren't in your immediate future, you can do some porting work on your manifolds while you're at it. I have a bud who has a highly modified ZZ3 TPI setup, he runs low 13's (altitude corrected) with self-ported factory TPI exhaust manifolds (dual cats, though).

 

you can always put on a shot of NOS too..
they just sold one on ebay for alittle over 200 bucks 75-125 hp


Sammy

 

-Link not allowed here.-

AJ

 

Thanks for the link and all the help you guys have been. I'm still waiting for parts to come in, but should be ready to start in the next week or so. Thanks again!!

 

Link above removed.

 

I've got know idea what you guys have against each other, but in my opinion any advice is better than none. As for now, here's what I have planned so far:

Install a Compcam 2040 cam and 1.94 intake valves, High-flow runners, TPIS AFPR, Custom PROM, Port the plenum and exhaust manifolds, and possibly NOS (if I can find a sys. for a decent price).

I've already have a High flow cat and Flowmaster cat-back exhaust, MSD HEI Module and Coil, and 8mm wires with Bosch Platinum 4+ plugs. I don't know if there's much more I can do without spending too much. I'm on a limited budget, but I've got a good start I think.

I've still got to decide on a torque converter for my 700R4. What stall should I go with? Any other HP ideas?

 

Installing larger valves is really kind of an expensive ordeal for not all that much gain. You'd be better off porting what you have and leaving the valve size alone. For info on porting, check the general tech board, theres a couple threads by Sitting Bull that will be helpful.

You could make your own AFPR, its not that hard. Vader has an article on it.

Custom PROM, burning your own? The off the shelf stuff is pretty useless, doesnt do a whole lot and is quite expensive for what little they change.

Rather than messing with the exhaust manifolds, you should consider getting some headers. The manifolds just cant be improved upon a whole lot.

Torque converter... well there are some people getting ok results with some of the converters out there, but the Vigilante is the way to go. A bit expensive, but worth it from everyone I have talked to. I have one sitting here, just havent installed it yet.