I have a 1987 305 tpi with 140k I just bought a 96 vortec 350 (complete) that has rebuilt heads 906 w/ new valves, seals,springs,rockers and pushrods. bottom end has piston slap. Im want to hone the block if possible , if not .030 over.I paid 250 for the motor and I was looking for opinions on what to do for the most cost efficient set up.. keep the tpi, and switch the manifold-injectors-knock sensors, or go with a carb manifold, carb ( I have a 650 vac sec,just needs rebuild), distributor, and lock up kit for the 700r4 I just had rebuilt( overhaul kit with 2400 stall,corv servo, .500 bv). Im just tryin to find out which way will get this 350 up and running cheaper, and what exactly I need to do for either. Thanks so much for any ideas. ps not looking to machine the heads(budget) but I did see some cone shaped springs for vortec heads that said up to .520 lift for under $100. might consider once I find out if there junk or not.

 

You don't hone to fix piston slap. You might knurl the piston skirts, but it makes more sense to bore the cylinders (basically more of a hone these days) to the next oversize and build from there. That's assuming the problem is piston slap.

The TPI Vortec set-up will cost a little more to support the Vortec engine properly, since you'll need runners as well as the base. Either set-up should have headers. Long-term the TPI will cost you less to operate.

The beehive springs are pretty good. But, it's the valve travel that you need to verify - with the retainers you're going to use, check each and every valve without the spring installed.

 

I just bought a 350 vortec myself for $250. I have the L31 heads and the rest is a stock shortblock. Are the vortec heads worth my time...I was thinking of buying an edelbrock top-end kit- heads, cam, intake...with my tax return. So my question is: I want to build an engine with 400+hp...should I use these L31's I got or just go big on the top-end. Also keep in mind I plan to bore the cylinders 30 over. And have the block hot tanked and re machined; I may try to stroke it out and build a 383 stroker. Is it worth it to keep these L31 heads for my stroker build or go for the edelbrock kit.

Also havent decided on fuel injection or carb. trying to keep somewhat of a budget....any help is great, thanks.

 

Check out the sdparts.com Vortec TPI crate engine. It has heads like yours but upgraded. It has the LT4 Hot Cam kit. With aftermarket runners, 52mm TB, and 1-7/8" headers, it puts out 360 HP.

That same engine with an RPM Air Gap and 750 Holley would make well over 400 HP.

TPI will hurt your power, no getting around that without many more $'s. But, carb will cost you more to run. It all depends on your priorities.

 

why do you say carb will cost more? Are you refering to the long run with reliability, or do you mean the initial switch from tpi to carb. Also Ive heard the carb will get the motor to put out more hp per $ put into parts. Thats what I really want to know... ex. If it cost me $500 to do the tpi (base injectors k sensor)or $500 to carb(base,dist,700r4 lu kit); will the carb make more hp. http://cgi.ebay.com/ebaymotors/SBC-V...mZ230219056587 this is a kit a member sent to me, What do you think?

 

You'll get better fuel economy with properly tuned TPI. You'll get more HP/$ out of carb.

That eBay Vortec spring "kit" is typical eBay blather. He repeats a long-discredited myth, in the fine print admits .520" lift is about all you can expect - basically a band aid on a sucking chest wound.

If you want it right, do it right.

 

i have the 350 vortec ( L31 ) and put the tpi on it,the edelbrock intake is all i needed,reused the factory runners.leave the tpi if your gonna keep it a street car. the L31 with the tpi on it is a beast!!!!!!!! i have the edelbrock headers on my car also.it wasent the cheapest option but its worth it.

 

Don't get the ebay springs. They are good to .520 lift at low RPM. They don't have enough pressure to keep the valves from floating. I contacted comp cams and got springs from them on my second time with on the same engine. With an xr 282 hr cam (similiar in specs to the LT4), I got 436 at the flywheel without anything special. Take your time and work over the combination and it should be good.