modifying an L-82
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
modifying an L-82
I know most people will say, "forget it, get new heads, cam, etc." but I want to keep this stock. What I am looking for is ways to boost this slouch of an engine. Really I was looking at getting the heads and intake ported out really well. The exhaust manifolds gotta go though, so I will at least put on headers for now.
I also was going to invest in a new camshaft, though I've heard many comments that the L-82 cam is pretty decent. Also the idea of using 1.6 rockers.
What about upping the compression a bit with flattops, or is this just pointless with the heads I have?
Any suggestions you have I'm interested, and I'm not limiting this with money.
I also was going to invest in a new camshaft, though I've heard many comments that the L-82 cam is pretty decent. Also the idea of using 1.6 rockers.
What about upping the compression a bit with flattops, or is this just pointless with the heads I have?
Any suggestions you have I'm interested, and I'm not limiting this with money.
Instructor
Joined: Jul 2006
Posts: 112
Likes: 0
From: vt
i guess i'm a little confused, you say that you want to keep your motor stock, but then you are willing to change the pistons and cam? why not the heads? if you want to keep your stock parts for a possible return to stock someday, i'm all for that, but if you're willing to change your cam/pistons, why not do the heads while you're at it. the money that you'd spend modifying your current heads wouldn't be worth it, and then you'd never be able to go back to stock.
Drifting
Joined: Oct 2004
Posts: 1,496
Likes: 1
From: Lafayette Louisiana
The heads are the limiting factor on the L82. Most say the cam is ok, the pistons are already flat tops, the forged crank provides an ideal bottom end so why not just change the heads to bump up compression and hp. Resistance is futile. 
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
i guess i'm a little confused, you say that you want to keep your motor stock, but then you are willing to change the pistons and cam? why not the heads? if you want to keep your stock parts for a possible return to stock someday, i'm all for that, but if you're willing to change your cam/pistons, why not do the heads while you're at it. the money that you'd spend modifying your current heads wouldn't be worth it, and then you'd never be able to go back to stock.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
Let me ask this: What is so limiting on the 882 head that cannot be modified? Valve size? That can be modified. Flow pattern? Port job. Rockers? Upgrade.
I've always heard that the 882 heads are terrible, but why.
I've always heard that the 882 heads are terrible, but why.
Safety Car
Joined: Oct 2000
Posts: 3,593
Likes: 103
From: Southern Indiana
I understand what you want, some people just think you have to junk eveything and start over.
Get you heads ported and polished and use a .019 thick head gasket.
If your going to change cams then instead of usuing 1.6 rockers get the right cam in the first place.
1.6s add around .030 to the lift, so just buy a cam with the specks you want. But do get roller rockers.
Your gears and stall is a limiting factor.
The Comp Cams 268 extreme is a good choice.
make sure your timing is maxed out and carb is matched to your engine.
Forget the shiny pullies and chrome add ons and spend the money on parts with purpose.
Headers= YES very easy to install, then have a muffler shop connect them up with some 2.5 pipe and free flowing mufflers, not stock.
Flowmasters or Dynomax super turbos, the rest or a waste of money on a popular name buying IE; Magnaflows, Borla or anything else that claims free flowing with an "S" pipe in the muffler= restrictive!!!
Get you heads ported and polished and use a .019 thick head gasket.
If your going to change cams then instead of usuing 1.6 rockers get the right cam in the first place.
1.6s add around .030 to the lift, so just buy a cam with the specks you want. But do get roller rockers.
Your gears and stall is a limiting factor.
The Comp Cams 268 extreme is a good choice.
make sure your timing is maxed out and carb is matched to your engine.
Forget the shiny pullies and chrome add ons and spend the money on parts with purpose.
Headers= YES very easy to install, then have a muffler shop connect them up with some 2.5 pipe and free flowing mufflers, not stock.
Flowmasters or Dynomax super turbos, the rest or a waste of money on a popular name buying IE; Magnaflows, Borla or anything else that claims free flowing with an "S" pipe in the muffler= restrictive!!!
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
I understand what you want, some people just think you have to junk eveything and start over.
Get you heads ported and polished and use a .019 thick head gasket.
If your going to change cams then instead of usuing 1.6 rockers get the right cam in the first place.
1.6s add around .030 to the lift, so just buy a cam with the specks you want. But do get roller rockers.
Your gears and stall is a limiting factor.
The Comp Cams 268 extreme is a good choice.
make sure your timing is maxed out and carb is matched to your engine.
Forget the shiny pullies and chrome add ons and spend the money on parts with purpose.
Headers= YES very easy to install, then have a muffler shop connect them up with some 2.5 pipe and free flowing mufflers, not stock.
Flowmasters or Dynomax super turbos, the rest or a waste of money on a popular name buying IE; Magnaflows, Borla or anything else that claims free flowing with an "S" pipe in the muffler= restrictive!!!
Get you heads ported and polished and use a .019 thick head gasket.
If your going to change cams then instead of usuing 1.6 rockers get the right cam in the first place.
1.6s add around .030 to the lift, so just buy a cam with the specks you want. But do get roller rockers.
Your gears and stall is a limiting factor.
The Comp Cams 268 extreme is a good choice.
make sure your timing is maxed out and carb is matched to your engine.
Forget the shiny pullies and chrome add ons and spend the money on parts with purpose.
Headers= YES very easy to install, then have a muffler shop connect them up with some 2.5 pipe and free flowing mufflers, not stock.
Flowmasters or Dynomax super turbos, the rest or a waste of money on a popular name buying IE; Magnaflows, Borla or anything else that claims free flowing with an "S" pipe in the muffler= restrictive!!!
Will upping the compression be wise though with these changes? If I really wanted to, couldn't I mill the heads a bit as well?
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Le Mans Master
Joined: Apr 2005
Posts: 6,363
Likes: 429
From: Seattle Area WA
You really can't mill the 882's since they are already pretty thin and it's very well known that they are prone to cracking. I'd much rather spend $800 on a new complete set of cast iron Dart Platinum heads that will outflow those 76CC 882 castings. You'll spend at least $800 on porting those 882s not to mention new valves or at least a multi angle valve job too. You'll be money ahead with the Dart's and they look relatively stock. Rebuild and recurve the distributor, get the Q-Jet set up correctly, and the stock L-82 intake is a good piece to use too. I agree with the exhaust system too. I installed the Summit headers, a 2 1/2" pipe kit from Allen's that I added a "H" pipe to and they flow into a set Dynomax Super Turbos. It sounds awesome. The L-82 cam is a good piece but I would advance it 2-4 degrees for some inproved bottom end. Aftermarket cams tend to have too much overlap which kills low end performance. The headers and dual exhaust will help, but IMHO, if you go with an aftermarket cam, I would have it ground on at least a 112 Lobe seperation angle (LSA) to reduce overlap.
Le Mans Master
Joined: Mar 2004
Posts: 7,507
Likes: 1,513
From: Little Rock AR
It would be very difficult for anyone to notice you have swapped heads as most of the head is hidden by the accessories. Nobody ever notices mine. 
This ups the compression and flow at the same time. The head swap changes the personality of the L-82 quite a bit. It doesn't run out of RPM's anymore. You can add the higher ratio rockers if you want but they will not do anywhere close to what you can get from the head swap.
FYI - If you are considering the Darts but still want to look totaly stock you might want to know a few things I ran into. The valve cover rails are raised up a little on Dart heads vs stock 882's. The only stock thing that does not just bolt back on is the factory EGR valve. The higher valve cover rails will cause interfearance with the stock cast aluminum valve covers and the underside of the EGR valve. The Iron Eagles do not have the exhaust passage so the EGR is non-functional at this point. The exhaust manifolds will also need to be dressed slightly with a die grinder on the top surface but that is a purely cosmetic area and not realy something to be concerned about. It does not show once they are installed either.
-Mark.
This ups the compression and flow at the same time. The head swap changes the personality of the L-82 quite a bit. It doesn't run out of RPM's anymore. You can add the higher ratio rockers if you want but they will not do anywhere close to what you can get from the head swap.FYI - If you are considering the Darts but still want to look totaly stock you might want to know a few things I ran into. The valve cover rails are raised up a little on Dart heads vs stock 882's. The only stock thing that does not just bolt back on is the factory EGR valve. The higher valve cover rails will cause interfearance with the stock cast aluminum valve covers and the underside of the EGR valve. The Iron Eagles do not have the exhaust passage so the EGR is non-functional at this point. The exhaust manifolds will also need to be dressed slightly with a die grinder on the top surface but that is a purely cosmetic area and not realy something to be concerned about. It does not show once they are installed either.
-Mark.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
Well, I guess nobody likes my idea of stock. I mean headers are absolutely necessary. I mean if I'm gonna get new heads I might as well get some AFR 195's. Then I can really make some modifications and get this car moving.
But what is the big problem with the 882 heads? Is it the 76cc's thats just too big?
But what is the big problem with the 882 heads? Is it the 76cc's thats just too big?
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
Well, I guess nobody likes my idea of stock. I mean headers are absolutely necessary. I mean if I'm gonna get new heads I might as well get some AFR 195's. Then I can really make some modifications and get this car moving.
But what is the big problem with the 882 heads? Is it the 76cc's thats just too big?
But what is the big problem with the 882 heads? Is it the 76cc's thats just too big?
Safety Car
Joined: Oct 2000
Posts: 3,593
Likes: 103
From: Southern Indiana
Just have somebody polish and clean up the rough cast in the bowls.
Upping the compression with the head gaskets won't put you in the danger zone. .019 gaskets is like milling .030 off the heads.
With a 4 speed and those gears , you can go up 1 or 2 sizes in the cam, like the 274 cam.
Go with a 110 lobe separartion, and go woth a set of $100 valve springs from Comp or Crane.
Not trying to build a 7 second screamer, just a street bad azz cruise night loper.
Upping the compression with the head gaskets won't put you in the danger zone. .019 gaskets is like milling .030 off the heads.
With a 4 speed and those gears , you can go up 1 or 2 sizes in the cam, like the 274 cam.
Go with a 110 lobe separartion, and go woth a set of $100 valve springs from Comp or Crane.
Not trying to build a 7 second screamer, just a street bad azz cruise night loper.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
Just have somebody polish and clean up the rough cast in the bowls.
Upping the compression with the head gaskets won't put you in the danger zone. .019 gaskets is like milling .030 off the heads.
With a 4 speed and those gears , you can go up 1 or 2 sizes in the cam, like the 274 cam.
Go with a 110 lobe separartion, and go woth a set of $100 valve springs from Comp or Crane.
Not trying to build a 7 second screamer, just a street bad azz cruise night loper.
Upping the compression with the head gaskets won't put you in the danger zone. .019 gaskets is like milling .030 off the heads.
With a 4 speed and those gears , you can go up 1 or 2 sizes in the cam, like the 274 cam.
Go with a 110 lobe separartion, and go woth a set of $100 valve springs from Comp or Crane.
Not trying to build a 7 second screamer, just a street bad azz cruise night loper.
Le Mans Master
Joined: Apr 2005
Posts: 6,363
Likes: 429
From: Seattle Area WA
Well if you are set on using the 882s then I would suggest that you find a quality shop for your head work that has "Bowl Buster" cutters to clean up your bowls and perform a mulit angle valve job. Several cutters these days cut a standard multi-angle job all at once anyway. This would be a lot cheaper than grinding the bowls by hand and provide you with good flow results. I've ported lots of heads and you will spend 16 hours minimum carefully cleaning up bowls. Translate that into a shop rate and you start having some money invested in these 882 heads. I would use a Fel Pro 1094 Hypalon coated steel shim head gasket which measures .015". Personally I do not like cams on 110 LSAs, they are fine for the cruise-in with their rumpty rump sound, but I would prefer a much snappier throttle response that a cam ground on a 112 or 114 LSA will provide in your mild 350 build. A new set of Sealed Power VS677 springs would be an excellent choice for freshening up your valve train as well.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
Well if you are set on using the 882s then I would suggest that you find a quality shop for your head work that has "Bowl Buster" cutters to clean up your bowls and perform a mulit angle valve job. Several cutters these days cut a standard multi-angle job all at once anyway. This would be a lot cheaper than grinding the bowls by hand and provide you with good flow results. I've ported lots of heads and you will spend 16 hours minimum carefully cleaning up bowls. Translate that into a shop rate and you start having some money invested in these 882 heads. I would use a Fel Pro 1094 Hypalon coated steel shim head gasket which measures .015". Personally I do not like cams on 110 LSAs, they are fine for the cruise-in with their rumpty rump sound, but I would prefer a much snappier throttle response that a cam ground on a 112 or 114 LSA will provide in your mild 350 build. A new set of Sealed Power VS677 springs would be an excellent choice for freshening up your valve train as well.
So whats the 882's problem? Is the combustion volume too large?
Race Director
Joined: Sep 2002
Posts: 10,362
Likes: 5
From: San Diego - Deep Within The State of CONFUSION!
More along the lines of I want to keep the visible parts stock. I want the original 882 heads on the motor, I just want to port them so I can get the flow. Same with the original intake. Internally, I'm willing to make the necessary adjustments to open the car up. This is what I'm willing to do, but what I need to know if its feasible.
I know in my engines future is a set of AFR's or at least Edlebrock aluminum heads.
Le Mans Master
Joined: Apr 2005
Posts: 6,363
Likes: 429
From: Seattle Area WA
They do have large chambers since these are smog castings, they are very thin so they tend to have cracks in them, and basically they have poor port design since they were never meant to be performance heads.
With that said, they can be made to work OK, but before I would spend $300 for guides and a valve job plus another $100 for springs, keepers and maybe new valves for another $150, and/or another $600-$900 for porting or a few hundred for bowl buster work I would think twice before sinking money into weak heads. For less money you can buy better 64-67cc heads with 180cc ports off the shelf.
With that said, they can be made to work OK, but before I would spend $300 for guides and a valve job plus another $100 for springs, keepers and maybe new valves for another $150, and/or another $600-$900 for porting or a few hundred for bowl buster work I would think twice before sinking money into weak heads. For less money you can buy better 64-67cc heads with 180cc ports off the shelf.
Last edited by Scott Marzahl; Jun 26, 2007 at 02:38 PM.
Le Mans Master
Joined: Mar 2004
Posts: 7,507
Likes: 1,513
From: Little Rock AR
GENERALY the lower the lobe separation angle, the "lopier" it will be with all else being the same. It will not sound "stock" with a narrow lobe separation angle such as 110 or 108 degrees. The added power will be more concentrated at a higher RPM and you will loose low RPM torque and efficency. If that sounds like what you want then go for it.
Wider lobe spacing will give you better road manners, efficency and a wider RPM power band with somewhat less peak power. Lots of this depends on stroke length and other factors so these are general statements. Bigger cube strokers can work fine on the street with lower lobe separation angles but narrow lobe centers on a short stroke motor make it very difficult to drive on the road. All the torque will be concentrated at high RPM and you will have no power off the line.
Hope this helps,
-Mark.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
The L-82 cam will not lope much even with the added compression.
GENERALY the lower the lobe separation angle, the "lopier" it will be with all else being the same. It will not sound "stock" with a narrow lobe separation angle such as 110 or 108 degrees. The added power will be more concentrated at a higher RPM and you will loose low RPM torque and efficency. If that sounds like what you want then go for it. Wider lobe spacing will give you better road manners, efficency and a wider RPM power band with somewhat less peak power.
Lots of this depends on stroke length and other factors so these are general statements. Bigger cube strokers can work fine on the street with lower lobe separation angles but narrow lobe centers on a short stroke motor make it very difficult to drive on the road. All the torque will be concentrated at high RPM and you will have no power off the line.
Hope this helps,
-Mark.
GENERALY the lower the lobe separation angle, the "lopier" it will be with all else being the same. It will not sound "stock" with a narrow lobe separation angle such as 110 or 108 degrees. The added power will be more concentrated at a higher RPM and you will loose low RPM torque and efficency. If that sounds like what you want then go for it.
Wider lobe spacing will give you better road manners, efficency and a wider RPM power band with somewhat less peak power. Lots of this depends on stroke length and other factors so these are general statements. Bigger cube strokers can work fine on the street with lower lobe separation angles but narrow lobe centers on a short stroke motor make it very difficult to drive on the road. All the torque will be concentrated at high RPM and you will have no power off the line.
Hope this helps,
-Mark.