Aaron-74

I have a set of 882 heads that will be an "over kill" for my motor. The have nicely pocket ported bowls. Ported much larger exhaust ports. Manley SS valves. 1.94/1.60 true 3 angle valve job. New valve seats and seals. Bronze valve guide liners. Comp Cams 1.50 single springs. It's been bead blasted. Decked on the intake sides and combustion side. Painted Chevy orange in High Temp ceramic paint.

since my motor is pretty much stock and my cam isnt all that radical. The exhaust ports will be a major over kill for my motor. My auto shop teacher told me they need to be on a 9.5:1 motor with atleast .510 270+ cam. Since they exhaust ports are so big, they will flow good. But there will be no velocity with my weak cam. So, how much do you think the heads would be worth. He told me I should try to get a set of Iron Eagle Dart heads. There the best out of the box street heads. But, I need to get rid of these heads first. I've got about 400$ in the, with receipts.


[Modified by Aaron-74, 2:35 PM 2/13/2002]


[Modified by Aaron-74, 2:37 PM 2/13/2002]

gerry72

Tell your teacher that the Dart Iron Eagles out of the box outflow those ported 882 heads on both the intake and exhaust. Either will work better on an engine with more compression and cam and either will really punch up the midrange on your stock engine even with the wimpy L-48 cam and 8.5:1 compression.

Aaron-74

He said I should be me concerned with velocity.

TedH

I have found the 882's to max out on torque at around 300ft lbs at around 2500rpm. They just run out of flow capacity. Go for the Darts; your engine will breath better and longer.

Aaron-74

but how much could I get rid of these 882 for. I KNOW the Darts are better...How much can I get rid of the 882's for.

john's '81 mouse

Not sure that you can get back your $400 investment in these heads, not at least for those of us looking to significantly improve performance and don't care about not being 'factory/NCRS original'.

These heads might be of some value, and perhaps worth close to your invest cost of $400 to a vette owner who wants to retain factory original appearing parts, but increase performance, perhaps someone who has an L82 vette engine, but believe the 'demand' side of this market equation is severely limited.

Guess you could post on e-bay with a $400 reserve, and see what you get.

Good luck.

KenSny

Given that these heads have dual heat riser ports and run really HOT and are therefore prone to cracking - who wants them? Maybe someone trying to maintain the stock part#s, but anyone going for performance will probably pass to aftermarket heads or some earlier stronger GM heads.

BTW: these heads were also used on the L82s (1975 for one) with 2.02/1.6 valves. Yes the cam was a little more than the L48 but not as much as your teacher recommended. They would really have to have had the exhaust hogged out to "need" that big a cam.....

Aaron-74

All I'm worried about is low-end torque. I could really care less if I make 1,000HP@ 7000RPM. I want 500ftlbs @ 3500.

With the cam and everything DD2000 says that I'll make 320HP and 402Ftlbs with STOCK 882 heads. With the darts with everything else the same It make 356HP and 420ft lbs.

Will the big exhaust ports REALLY hurt my power that much??

I beleive my teacher for the most part because he's build MANY motors, is on a Top Fuel team and runs in the Super Gas on week ends. So, I'm pretty sure he knows what he's talking about.

Lt1er

Send him back to school! :yesnod:

I'm suprized that you didn't go ahead and go 2.02 intake. I had a car with fully modded 882's I had the full D port exhaust screw in studs guide plates 2.02/1.6. Springs for .540 lift.

Traditionally the exhaust side is very weak in CFM flow and everything should be done to help it out (Bigger Valves and Porting) The big determining factor in port velocity is not just the head. How restrictive the exhaust is plays a bigger part.

Many cams have wide split durations to help poor exhaust flow with longer duration and higher lift than the intake.

With small lift hydro cam like your and cast iron exhaust you need all the help you can getting the high pressure hot gas out as fast as you can. The higher the flow of the ports the less cam you need to make the same HP.

Aaron-74

I had thought about going with the 2.02/1.60 valves. But then there's a lot of valve shrowding,right? Then I'd have to grind the chamber walls and that would be lowering the compression more than it is.


So, your saying with the 882 heads, and the HUGE exhaust ports, and the HUGE headers, with 2.5 pipes and Dyno-Max Bullet mufflers (HIGH flow exaust) I will still make good power/torque with the 882 heads???

gkull

My L82 came with 2.02/160 and then I worked them over and had hedman 1 5/8th headers true duals no cats.

The first thing to ever really wake up my motor was more compression. during one upgrade all I changed was to ported 186 casting double hump heads with the same 2.02/1.6 and just under 64 cc So it went to @10.7 c/r with my two valve relief flat tops.

The flow and ports were about the same, But you could feel the difference.

I now have massive exhaust ports with the biggest valves that will fit in the heads. 2.08/1.625

KenSny

Depends on what you mean by HUGE headers. The bigger the tube the less power you are going to see down low with your setup.

BTW: Just because he teaches doesn't mean he can't make mistakes..... or maybe you're not hearing something he's implied, but not directly saying. Anyhow what he's saying doesn't make much practical sense.

Ganey

You do not have huge headers or even big valves. Sounds like you would be fine. You might want to get a photo or measure final port size & post.
Which carb are you going to run?

TedH

I paid $300 for a fresh set with all new moving parts from an outfit in Oakland, CA. So, used, I'd say $200 or less.

gerry72

The theories you want to understand from your teacher are flow, scavenging, velocity, and gas dynamics. Computational fluid dynamics are complex but there is much to be said for practical experience with street cylinder heads. There really isn't much of a market for your ported/modified 882 heads except, as previously stated, to someone looking for a set for a restoration project. That being the case, I couldn't see anyone knowing what 882 heads are paying more than around $300.00.

jaggeedfire

I got mine for $130. That was for the heads completly rebuilt and no core!! I did the pocket port and gasket matching. I think if your really wanting to make some power, go to a good aftermarket head as a good base. The 882's just will never flow as well as a base aftermarket head. I went with the 882's because I was on a budget when I built my 350, but I built it so later I could put on better heads. If given the chance, go with something better.

jaggeedfire

Aaron-74

I don't know what size my headers are, but the size of the pipes where the flange is is bigger than standard.

I know my motor has a LOW compression. No more than 9.0:1. So, I'm kinda screwed there.

Ganey-I'll be running a Holley 600 elec. choke with vac. secondaries.

Ganey

You really don't want more than 9.5 & normally those heads are cut to raise c/r.

Aaron-74

There getting milled, but not enough to really see a difference.

There 1 5/8 headers with 2.5 dual pipes being put on..


[Modified by Aaron-74, 5:52 PM 2/14/2002]