I work in a machine shop and have been remanufacturing and porting heads. I recently got a good deal on a set of heads from a '02 Grand Am 3400, but they appear they were left in the weather for a short time. I'm sure the previous owner felt "Hey, they're aluminum and it wont hurt" not thinking about the hardened steel seats.

The seats have a 5 angle vale job from the factory and I wasn't going to buy the equipment yet, but I need it anyways and was just wondering if anybody here has experience with the different brands of seat cutters/grinders.

I have been shopping around and found a good deal on the Neway carbide seat system, but have never used it and was hoping for some feedback/discussion.

The next setup I found is by Goodson and is quite a bit more expensive (more then double) but allows a radius cut on the seats with only a small flat surface for the sealing angle. Has anybody had a radius cut on their seats and flowed the heads?

Thanks in advance,

-john

 

i'll PM you a link for a website, that I don't want posted on here, because 16 year old kids with uneducated questions will jump ship over there, and that board is much higher end then this board and others.

 

yeah your gonna have to find more specific forums or areas for that kinda stuff. not many ppl own machine shops here. There was a forum that i been to that had alot of cylinder head builders and shop owners on, if i can get that link maybe you can sneak around in there and see what they have to say. I think i favorited it

 

Thanks to both of you!

I kind of browsed Xpndbl3's link and didn't see a specific area for head design, but I will be signing up to both.

Hopefully in the near future we can help some of the guys here go a little faster .

Even though no one here had a specific answer, it will be answered in a round-about way


-john

 

Now that's what I'm talking about. Thanks for the link, again.

Xpndbl3, your guys sent me to Orr89Rocz's link, lol. Asked the same question there and haven't gotten an answer otherwise.

A thousand thank you's to both.

 

yeah man its a sweet site

 

Care to share what board you’re talking about?

The only place that I can think of offhand is ST’s engine tech forum (bunch of guys there with machine shops and there have been a few discussions there about the different seat cutting setups), and then there is an “advanced tech” forum on another gm site but that one is largely dominated by a few *******s that really seem to feel that everything mentioned is theirs, proprietary and otherwise won’t share enough info to have a real discussion about anything.

I’ve been hanging out at a few engineering forums also, but it seems to me that for the most part there is more of a push for discussing efficiency and marginal tinkering with new technology rather than serious tech.

As far as a theoretical answer to your question, distinct angle cuts vs radiused seats both have advantages and disadvantages, and to a large extent, which is best depends on the particular engine and what you’re trying to achieve, just like whether you want sharp valve margins or radiused margins depends mostly on which valve it is, but also on chamber and port designs.

Secondly, I’ve yet to see any hard evidence of a 5 angle job resulting in better power production than a properly cut and blended 3 angle job. There are some serious, high flowing heads with 5 or more angle jobs on them, but I would give you a chicken/egg argument there, are they making more power because of the extra cuts or are they making more power because more attention was paid to doing it right in the first place?

 

Yeah i was refering to Speed Talk

 

In the origionl post, I was asking because the heads already have a 4angle valve job (I said 5), and the 3500 V6 heads now have a 5 angle. I started shopping for the valve grinding equipment because we need it in the shop anyways.

I have read that people who experimented withe the radii cuts, found a slight gain on the exhaust seat, but not as much on the intakes.

I'm going to stick with the plan and grab the Neway system. The kit I was looking at comes with the 15*, 30*, 46*,60* cutters, top pilot and a handful of guide pilots for $400. Then add the 75* cutter to make the full 5 angles for another $125. Not a bad price I think, especially if you never have to dress a stone again. I also liked that it can be hand driven (even though we have machinery) and one is less likely to go overboard on the cutting.

 

I've used it, the stone cutters leave a better seat finish but if accuracy is your thing its more accurate and easier to cut the same widths from one seat to the next doing them by hand.

 

Smooth enough to get away with only lapping after?

 

Definitely. Thats what I did after I was done.