How much hp/lb-ft?

[SwiftDrift]

If i had a low mile 3500 swapped to the 65mm tb, hollowed the cat, ran a flowmaster 80 series, maybe ran headers, about how much torque and hp would it put out? And also, how far can i cam it like this, and how much hp and torque would it have then? Sorry for asking a million questions in my posts, but i love learning about these engines.

[caffeine]

How much hp/lb-ft?

Should make about 200whp/250ft lbs (torque peak @ 4800 rpm and hp peak @ 5000ish).



With 65mm TB, 3500 exhaust manifolds, crush bent y-pipe, stock Fiero air cleaner/filter.

[Superdave]

What exactly do you mean by "How far can I cam it like this?"


So, your combo basically ends up as a stock 3500 (stock TB is 65mm) with a hollow cat (which hurts exhaust flow) and an 80 series Flowmaster (which is not a very free-flowing muffler).. You'll be right around what Caffeine said.

What type of headers you run will determine a few things, equal length longtubes make better torque and more peak HP. Shorties are less predictable but typically make less torque than LT's however similar HP.

What trans you have is going to make a big difference on RWHP. Most 3500/5 speed Jbodies are putting down a little over 200 WHP, One that I can recall with a set of WOT's headers made around 215WHP but with some other upgrades like a good exhaust and intake he'd probably be a little higher. That's around 235HP @ the crank. 34hp more than stock application/tune.

[SwiftDrift]

when i hollowed my old grand ams cat, it had more pull to it. made it noticeably peppier. i figured the tb was smaller just because people reffered to the 3.6s tb as a 65mm... i just like how the 80 series sounds. and for the cam, i just want to know how much headroom i have without porting anything. i want the cam as close to the limits of the ports as possible, i will probs need a custom grind because i want to use 100% of the potential of the ports. i may polish them. and while its apart i will balance the assembly.

[caffeine]

You can probably run whatever cam up to the point where piston-valve contact becomes an issue. Any head porting will help get more out of it though.

[SwiftDrift]

are there any cams i can throw in that will bring it close to 300lb-ft? while maintaining somewhat decent hp..

[caffeine]

I'm hoping to dyno my Fiero soon which has a fairly wild cam.

[SwiftDrift]

one of my dads old friends got wierd results from putting a rough cam in a stock motor, whats the worse that could happen when putting in a mean cam?

[robertisaar]

match parts, trust me.

what happens when you don't is you get a 83 el camino with a 350 with a weak intake, stock heads, monster cam, good long-tube headers, giant carb, 11.5" wide tires with a 2.xx rear end.

absolute crap economy, not that great of output, will do 60MPH in 1st and is hell to drive.

[SwiftDrift]

it probably wont decrease power, but are there cases where a milder cam will give better performance than the harshest strip cam on a stock motor?

[robertisaar]

yes, think of it this way: heads, intakes, exhaust are all setup to generate maximum VE at around 4,000RPM, then you throw in a cam that wouldn't normally peak until 7,000, you end up with a pretty pathetic power curve.

it would sound great, but it would be slow, to say the least.

[SwiftDrift]

uhm, well what cam would you recommend??

[1988GTU]

Probably stay away from lift, dont wonder away from the stock lsa too much, and focus on duration. If you feel you should want more lift, might try messing with the rockers IF you can even source something with a different ratio than stock that will be worth the change.

Sadly, valve springs are going to need to be upgraded anyway.

[Superdave]

yes, think of it this way: heads, intakes, exhaust are all setup to generate maximum VE at around 4,000RPM, then you throw in a cam that wouldn't normally peak until 7,000, you end up with a pretty pathetic power curve.

it would sound great, but it would be slow, to say the least.

Sounds like what's under the hood of my Nova. Massive cam, great intake/carb/headers and trash heads. My 3500 made more HP than my 355 does. lol




WOT-Tech offers a cam selection service, Ben can help you design something that will do what you need it to do. Set some goals, make a solid plan and then Ben can help you out. Like Robert said, everything needs to match or you'll end up with disappointing results.

[SwiftDrift]

well i want about 270 lb-ft of torque, but i dont want to sacrifice top end. for hp i would be happy to get at least 250. i dont have a job right now but i am getting one shortly. how much is a custom grind roughly?