engine performance guess's, cam advice.
Thread Starter
Pro
Joined: Apr 2015
Posts: 551
Likes: 142
From: Warrington PA
engine performance guess's, cam advice.
going to do a freshen up on a rebuilt engine (less then 3000 miles) was done by previous owner. Not looking for a race engine just a good street performer that can handle pump gas, for my '74.
engine runs good now but the stock 882 heads are killing it, short block has flat top KB hyperurtectic pistons, stock block (has not been decked)so looking to put a set of used/freshened up pro topline iron heads (167cc runners/67cc chambers/1.94-1.60 sst valves/ hardened ex seats/.545 milodon springs), looking at a comp cams X series cam?
want a cam that has some lobe, makes power but is still streetable on pump gas and and works with the trans/converter & existing gears (th-400,shift kit,10" 2500 stall converter,3.08 gears)
I am thinking I will come in around 9.5 to 10-1 compression with the set up mentioned above.
what cam can any of your guys recommend, anyone have a similar set up?
engine runs good now but the stock 882 heads are killing it, short block has flat top KB hyperurtectic pistons, stock block (has not been decked)so looking to put a set of used/freshened up pro topline iron heads (167cc runners/67cc chambers/1.94-1.60 sst valves/ hardened ex seats/.545 milodon springs), looking at a comp cams X series cam?
want a cam that has some lobe, makes power but is still streetable on pump gas and and works with the trans/converter & existing gears (th-400,shift kit,10" 2500 stall converter,3.08 gears)
I am thinking I will come in around 9.5 to 10-1 compression with the set up mentioned above.
what cam can any of your guys recommend, anyone have a similar set up?
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
That set up gives you 9.7 CR if the pistons are 7cc flat tops and you use a .015 felpro head gasket. That gives you lots of options for a cam.
If you go with a 270 advertised duration and a 108 LSA you get 8.08 dynamic. Isky has a lot of 108 LSA cams.
Sounds like you are talking flat tappet cam.
XE 268 would fit the bill pretty good. Gives you a 8.03 DCR.
An XE262 might work as well. DCR is getting high for an iron head though at 8.19 DCR.
I have read about XE cam failures with the flat tappet so that is a consideration.
If you go with a 270 advertised duration and a 108 LSA you get 8.08 dynamic. Isky has a lot of 108 LSA cams.
Sounds like you are talking flat tappet cam.
XE 268 would fit the bill pretty good. Gives you a 8.03 DCR.
An XE262 might work as well. DCR is getting high for an iron head though at 8.19 DCR.
I have read about XE cam failures with the flat tappet so that is a consideration.
Last edited by REELAV8R; Dec 30, 2015 at 07:11 PM.
Thread Starter
Pro
Joined: Apr 2015
Posts: 551
Likes: 142
From: Warrington PA
9.7 is fine with me & I was going to use a .015 head gasket. so many cams to choose from, thats why i was hoping for some fellow vette guys to tell me about there combos if they were close to mine.
thanks for the info
thanks for the info
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Hard to go wrong with an Isky 270 mega cam afr 180 head 650dp, good dual plane headers etc. Can daily drive if you want, power comes on hard.
Not saying its the best combo in the world but will sure work well if youre sticking to h. flat tappets
Not saying its the best combo in the world but will sure work well if youre sticking to h. flat tappets
Melting Slicks
Joined: Apr 2009
Posts: 2,632
Likes: 112
From: Great Plains Iowa
going to do a freshen up on a rebuilt engine (less then 3000 miles) was done by previous owner. Not looking for a race engine just a good street performer that can handle pump gas, for my '74.
engine runs good now but the stock 882 heads are killing it, short block has flat top KB hyperurtectic pistons, stock block (has not been decked)so looking to put a set of used/freshened up pro topline iron heads (167cc runners/67cc chambers/1.94-1.60 sst valves/ hardened ex seats/.545 milodon springs), looking at a comp cams X series cam?
want a cam that has some lobe, makes power but is still streetable on pump gas and and works with the trans/converter & existing gears (th-400,shift kit,10" 2500 stall converter,3.08 gears)
I am thinking I will come in around 9.5 to 10-1 compression with the set up mentioned above.
what cam can any of your guys recommend, anyone have a similar set up?
engine runs good now but the stock 882 heads are killing it, short block has flat top KB hyperurtectic pistons, stock block (has not been decked)so looking to put a set of used/freshened up pro topline iron heads (167cc runners/67cc chambers/1.94-1.60 sst valves/ hardened ex seats/.545 milodon springs), looking at a comp cams X series cam?
want a cam that has some lobe, makes power but is still streetable on pump gas and and works with the trans/converter & existing gears (th-400,shift kit,10" 2500 stall converter,3.08 gears)
I am thinking I will come in around 9.5 to 10-1 compression with the set up mentioned above.
what cam can any of your guys recommend, anyone have a similar set up?
With the tall 3.08 gears you'll need a short duration high lift cam like a 268H Competition Cams.
Thread Starter
Pro
Joined: Apr 2015
Posts: 551
Likes: 142
From: Warrington PA
Yes the cam would be a hydraulic cam, I plan on going to 3.36 or maybe 3.55 gears in the future so I. Need to make sure the cam I choose works with my 3.08s and will be even better with either of those gears (most likley the 3.36s).
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Verdad Gallardo
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
DO NOT buy a POS cam called a ZZ9 from TPIS Chaska Minn......
I made that mistake some years ago, and it drove me krazy.....damn nearly destroyed the car looking for it, wiped cam lobes that yielded a very INTERMITTENT rough idle.....mostly rough, but every once in a while it was smooth as silk.....damn CAM.....
I made that mistake some years ago, and it drove me krazy.....damn nearly destroyed the car looking for it, wiped cam lobes that yielded a very INTERMITTENT rough idle.....mostly rough, but every once in a while it was smooth as silk.....damn CAM.....
Thread Starter
Pro
Joined: Apr 2015
Posts: 551
Likes: 142
From: Warrington PA
Safety Car
Joined: Jan 2009
Posts: 4,000
Likes: 299
From: New York
going to do a freshen up on a rebuilt engine (less then 3000 miles) was done by previous owner. Not looking for a race engine just a good street performer that can handle pump gas, for my '74.
engine runs good now but the stock 882 heads are killing it, short block has flat top KB hyperurtectic pistons, stock block (has not been decked)so looking to put a set of used/freshened up pro topline iron heads (167cc runners/67cc chambers/1.94-1.60 sst valves/ hardened ex seats/.545 milodon springs), looking at a comp cams X series cam?
want a cam that has some lobe, makes power but is still streetable on pump gas and and works with the trans/converter & existing gears (th-400,shift kit,10" 2500 stall converter,3.08 gears)
I am thinking I will come in around 9.5 to 10-1 compression with the set up mentioned above.
what cam can any of your guys recommend, anyone have a similar set up?
engine runs good now but the stock 882 heads are killing it, short block has flat top KB hyperurtectic pistons, stock block (has not been decked)so looking to put a set of used/freshened up pro topline iron heads (167cc runners/67cc chambers/1.94-1.60 sst valves/ hardened ex seats/.545 milodon springs), looking at a comp cams X series cam?
want a cam that has some lobe, makes power but is still streetable on pump gas and and works with the trans/converter & existing gears (th-400,shift kit,10" 2500 stall converter,3.08 gears)
I am thinking I will come in around 9.5 to 10-1 compression with the set up mentioned above.
what cam can any of your guys recommend, anyone have a similar set up?
Look up a ZZ465 ..Or ZZ430 .. If you get heads in line with GM fast burns the cam specs for those 2 motors are good on the street and have some nuts ..
I should have the ZZ430 cam and lifters on a shelf at the shop.
Last edited by diehrd; Jan 1, 2016 at 12:05 PM.
Racer
Joined: Jul 2009
Posts: 344
Likes: 5
From: oak harbor wa
Gears will open up your choices
Like others have said with your rear gears stay out of the lower LSAs cams it will move the power band way to high in the rpm to work for you and just upset you. If you want it to sound mean the mother thumpr cams are pretty good but $$. The 108 lsa cams might give you a head ache with the power brakes.
With your gears I would suggest the summit sum-1104 unless you decide a gear change, if you wanna have a little fun and still hit the highway go to 3.55 gears and the summit 1106.
I have never had a issue with the summit cams but use other people's lifters.
With your gears I would suggest the summit sum-1104 unless you decide a gear change, if you wanna have a little fun and still hit the highway go to 3.55 gears and the summit 1106.
I have never had a issue with the summit cams but use other people's lifters.
Last edited by lowes-yellow77; Jan 3, 2016 at 11:27 PM. Reason: Wrong thread
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
Like others have said with your rear gears stay out of the lower LSAs cams it will move the power band way to high in the rpm to work for you and just upset you. If you want it to sound mean the mother thumpr cams are pretty good but $$. The 108 lsa cams might give you a head ache with the power brakes.
With your gears I would suggest the summit sum-1104 unless you decide a gear change, if you wanna have a little fun and still hit the highway go to 3.55 gears and the summit 1106.
I have never had a issue with the summit cams but use other people's lifters.
With your gears I would suggest the summit sum-1104 unless you decide a gear change, if you wanna have a little fun and still hit the highway go to 3.55 gears and the summit 1106.
I have never had a issue with the summit cams but use other people's lifters.
Both the 1104 and the 1106 summit cams have long slow ramps on the cam giving lot's of overlap reducing cylinder pressure. Not a real good situation for a 3.08 rear diff.
Racer
Joined: Jul 2009
Posts: 344
Likes: 5
From: oak harbor wa
Cam
I run a 108 and get 14" of vacuum at a 800 rpm idle, more than the brakes or vacuum acc need. Even in gear with a 600 rpm idle I get 10" of vacuum. Granted it is a roller cam so I get a bit more than a flat tappet but 108 is not a vacuum killer unless the overlap gets excessive.
Both the 1104 and the 1106 summit cams have long slow ramps on the cam giving lot's of overlap reducing cylinder pressure. Not a real good situation for a 3.08 rear diff.
Both the 1104 and the 1106 summit cams have long slow ramps on the cam giving lot's of overlap reducing cylinder pressure. Not a real good situation for a 3.08 rear diff.
and 14'' on a 108 lsa is pretty good I'm at about 12 on a 110 lsa sitting at 850rpm
Drifting
Joined: Mar 2006
Posts: 1,263
Likes: 188
From: Wabasha Mn
The isky 264 mega cam 214-214 450 lift 108 lsa is one step below the 270 mega camband will have better low end. Used one in my 76 l82, had better low and mid range than the l82 and had plenty of vacuum.
Thread Starter
Pro
Joined: Apr 2015
Posts: 551
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From: Warrington PA
lots of good info here, thanks guys. I have to run the 3.08's for awhile ($$$) so I may have to suffer a bit with the cam & those gears for now? when I do the gear change I was leaning towards the 3.55 set up too.
I looked at the summit 1103-04-06 cams. this car will be a driver, just want something that runs better (way better) then a stock L48, still is drivable, has good power & sounds cool (not stock/not street strip). i want to make a decision because the more people I talk to the more it makes me change my mind which intern increase's my budget & timeline because I start thinking of doing other things. I know for a fact there are probably a few dozen owners locally in the corvette club or at local cruise nights with very similar set ups but its winter no ones cruising now for me to go hear it and ask them for there cam opinions. I have to rely on what I get from personal experiences on the net.
thanks, Paul
I looked at the summit 1103-04-06 cams. this car will be a driver, just want something that runs better (way better) then a stock L48, still is drivable, has good power & sounds cool (not stock/not street strip). i want to make a decision because the more people I talk to the more it makes me change my mind which intern increase's my budget & timeline because I start thinking of doing other things. I know for a fact there are probably a few dozen owners locally in the corvette club or at local cruise nights with very similar set ups but its winter no ones cruising now for me to go hear it and ask them for there cam opinions. I have to rely on what I get from personal experiences on the net.
thanks, Paul