1.88 vs 2.02 Valves

[AprilsPink72Cuda]

Well, yesterday I got my heads off and will be sending them in to be redone including a 3 angle valve job.  My J heads have the small valves.  I was wondering if anyone had any info on changing to the 2.02 valves.  What kind of price difference do you think I will see at the machine shop, and do you think the results will be worth the money?

Also, what do you think about this cam?  280*/474" for my 340?

Thanks guys!      

[CudaNut]

A lot depends on the rest of the combo...compression, intake, headers, gearing. The large valves hurt torque a little on the low end but the big valves breathe better up top especially with a little bowl work on the heads. A few years back I ran a 340 in a 72 Cuda with the exact same cam you mention, it had  10-1 pistons, 1.88 "J" heads, dual plane Edeldrock with 700 DP, headers and 3.91 gearing. I switched to the 2.02 heads and it picked up 2/10 in the 1/4 but my 60ft and 1/8 times were slightly slower.

[AprilsPink72Cuda]

I guess I should have mentioned that I will be using a 6 pak set up, I have 4:10s and TTI Headers.  Not sure about the compression.

[Chryco Psycho]

can you gat a set of the truck 308 castings locally
?
 They are worth 40 hp , seriously , I have witnessed it twice on the dyno , far better heads
 the 474 cam works well , too bad the 471 isn`t still available , too bad the .474 isn`t available in the 114 cl version

[AprilsPink72Cuda]

Thanks Chryco, I am going to see if I an find a set of the 308 castings.  I forgot all about those.  Do you think it is going to be worth my while to go with the 2.02s?  Will I notice a big difference with my everyday driving on the street?

[Oldschool]

April,  it sounds like you are very interested in getting the most performance potential from your small block.  I base this on what you already have done.  Cam, 6-pack, Tti headers, & 4.10 gears.  If you want to really let her breath, get the 308's.  Will you feel the difference by "seat of the pants?"  Yes, but the difference will be above 2500 rpm's. Anytime you are wanting performance, you must let the engine breath. That's what these heads/valves will do. If you can't find the 308's, it would probably still be worth the effort to get the 2.02's installed along with appropriate bowl work. It's all about the breathing. Just my         .......Oldschool

[moparnut]

can you gat a set of the truck 308 castings locally
?
 They are worth 40 hp , seriously , I have witnessed it twice on the dyno , far better heads
 the 474 cam works well , too bad the 471 isn`t still available , too bad the .474 isn`t available in the 114 cl version

Chryco What year trucks were these on?thanks

[MEK-Dangerfield]

I appreciate what she wants to do, but the one unknown is her torque converter. All this new found power and all, I wonder if it can handle it?  

  Mike

[Chryco Psycho]

87-92 360 trucks , yes April I would use the 2.02 in you application Assuming you wil be bowl porting the heads
 if she cavs the converter I guess it will be replaced next

[Follicly Challenged]

Ever thought about using some "cut down" 2.02 valves ?

We found great success, as in "quicker off the turns" in CASCAR by cutting down some 2.02's to 1.97", gave back valve "margin" on some wore out pieces. At the time, we were just looking for "Anything to get back running", but stumbled upon some huge torque increases. Yes, we were using 308 heads back then. This assumes the stems aren't wore out too of course.