ive been considering doing the heads on my LO3 guys and this may have come up in a previous thread but my question is are those heads bolt on and go mods or do they need a lot of tuning with the prom??

if theres another thread can i get a link?

thnx,Dennis

 

I dont know if they would need much tunning by them selves, but if you are running a stock cam I wouldn't waste the time or money.I dont think you would see much improvement. If you go to a bigger cam and heads you will need to do prom tunning.

I used S/R torquers with a ZZ4 cam and broke like 11 out of 16 spring dampers even though I did not reach the max rated lift for the heads. I emailed a tec at World products to find out why but they wouldn't respond. I have also read in other posts about broken dampers on S/R heads.

If I was doing it all over I might use modified (for extra lift) vortec heads, or maybe Edelbrock Etecs. World Products won't get another dime from me.

 

The heads should be a direct bolt on. You will see a gain especially in top end power since the exhaust and intake runners are significantly bigger than the 187 castings and the S/Rs eliminate the valve shroud on the intake runner and the cast in swirls that generate that harsh low end torque you find in a stock L03. I had a picture comparison awhile back where I had 416-187-S/Rs side by side and you could see the difference in the heads. I just have to find the pics.

I bought bare S/R castings and assembled them with Comp Cams parts and never had a problem with anything breaking.

 

As soon as you ad mods to these cars you are gonna have to get into prom tuning. Even a full exhaust makes the stock tune inadequate.

 

thnx for the input guys

 

Are the S/Rs 100% emissions compatible without any special work? I think I remember a post a looong time ago saying that you have to tap into the heads to get them to work the EGR functionaly. Is this true? Reason being I'm thinking about changing heads this summer, and they come as a complete set; or I'm going to get some 305 TPI heads.

 

That is for the vortec heads. The Worlds have an EGR crossover.

 

Thank you very much, Shifty