I'm planning on my 3.1 build up (still) I've used dyno2000 to just get a feel for what may work. what do you think of this cam and every thing? I'm just looking for about 200HP and decent TQ. I think this set up would pull that off.

I've got an 85 Bird with 2.8 orginaly, and as such I have the 3.42 gearing so take off should not be a problem. Not looking for a race setup just a quick car to have fun with. Other question would this work well for a turbo? (and correct my bore and stroke if need be I'm not sure on those.)

 

any one? bump.

 

Here's the file I use to simulate a completely stock 2.8. It's pretty accurate, although the torq's exaggerated as DD2000 tends to do. Stroke on the 3.1 crank is actually 3.307" What pistons will you be using? Stock 3.1 or milled 2.8? Head porting? Induction mods?

 

I was going to use aftermarket pistsons. raise the compression a little (9.5:1) probably hyperectic (or whatever that word is) ported heads, biggest valves I can get to fit, this is going to be just a temp build to get my car running so I can actually drive it. I will probably put pacesetter headers on it though, I could go complete stock, but I figured if I've got it tore down might as well add some power to hold me over while I create a 3.4 hybrid turbo, rebuilt trans, and 4th gen rear ^_^) t

 

There aren't many aftermarket pistons available. The only ones I'm aware of are the probe forgings the fiero store has been hanging onto. You'll have to come up with a combo of gm parts that get you close to where you want to be. If you mill 2.8 pistons to zero deck height you'll get about 10.4 compression. You'll need a larger cam for that much compression to be useable with cheap gas, but since it sounds like you're planning on a custom grind anyway that won't be a problem.

 

the 2.8 pistons would be too small though diameter wise though wouldnt they? (or is that what milling is? making them bigger some how? I'm up on that stuff) i was going to get a master rebuild kit from northernautoparts.com they have the pistons for a 3.1 RWD GM application in stock sizes up to 40 over. I was thinking about just getting it witha 20 over bore to clean it up and pick up a cube or two.

OR since this is just a temp engine, should I just rebuild it to stock specs and throw in a delta 260 or melling MTC-5 cam and call it a day? I really just want it to run again and be enough to beat a civic or focus..

 

The 3.1/2.8 have the same bore. If you're spending the money to rebuild it you might as well put together a combo that'll give you some umph. Milling the piston crown (top of the piston) down on 2.8 pistons to zero deck height (level with the block) will give you 10.4 compression and an excellent .04" quench height. A delta 260 cam won't give you enough intake duration to use that compression on pump gas, look for something with an intake closing point of about 40*. Both the comp 16-115-4 and 16-233-4 will have enough duration, the 16-233-4 will make more hp higher in the powerband and the 16-115-4 will make more torq, but neither are a very good choice for turbocharging. Here's a combo I made with milled 2.8 pistons and a cam that would work well with turbocharging and still give you the right int. closing point with a 4* retard (easily done with a cloyes timing chain).

 

Thanks for your help, I'm really liking the comp cams 16-233-4. I think the smaller starting tq is good for my car because the trans is stock and its an open rear diff. Once I get the trans rebuilt and the rear a locking diff I'll look at something with a higher low end tq band. off hand how much TQ will the V6-700R4 generally handle?

 

I'd guess about 300ft/lb, maybe more. You can get more life out of it with fresh trans fluid and a shift kit. You can get a regrind done by delta for about the same price as a new cam.