advice on cam choice for 74 l48 with dart heads
#1
Safety Car
Thread Starter
advice on cam choice for 74 l48 with dart heads
I recently bought a project 74 with the l48 /th400 and After confirming the compression is good (155psi on all 8 cylinders)? I started looking for upgrades.. I picked up a set of dart iron eagle 180 heads (65cc I believe) and crane gold roller rockers for 300 bucks on Craigslist. I intend on purchasing the obx side pipes and baffles for those. The car has a new edelbrock performer intake and Carb (600) and hei style distributor.
My question is what would be a good choice for a came for low and mid range torque ? (street use only) I'm just looking to wake it up a bit... I do like the choppy idle of the more extreme cams but realize this may not be the possible with a mild cam which would be a better choice for me? .. also any ideas what head gaskets to go with to raise my compression a bit ...say to 9:5 again I'm looking for street ability and more torque?
I've been doing a lot of reading and there are so many choices and options... I don't want to make a mismatched purchase?
My question is what would be a good choice for a came for low and mid range torque ? (street use only) I'm just looking to wake it up a bit... I do like the choppy idle of the more extreme cams but realize this may not be the possible with a mild cam which would be a better choice for me? .. also any ideas what head gaskets to go with to raise my compression a bit ...say to 9:5 again I'm looking for street ability and more torque?
I've been doing a lot of reading and there are so many choices and options... I don't want to make a mismatched purchase?
#3
Race Director
Felpro 1094 head gasket.
This cam & lifter kit.
http://www.summitracing.com/parts/HRS-CL111145-10/
It will give you the sound you want and the operating range is perfect for your TH400 (it has a 2000 stall convertor stock) and 9.5 to 1 with iron heads. It will likely get you 25-30 HP over a comparable flat tappet with your heads.
This cam & lifter kit.
http://www.summitracing.com/parts/HRS-CL111145-10/
It will give you the sound you want and the operating range is perfect for your TH400 (it has a 2000 stall convertor stock) and 9.5 to 1 with iron heads. It will likely get you 25-30 HP over a comparable flat tappet with your heads.
#4
Safety Car
Thread Starter
Thanks for the replies... That cam is a bit on the high side as far as price compared to other ive seen. Not sure if I will be able to justify it to myself... I had to spend a lot on interior restoration and still have to tackle the body work.... two terrible paint job layers to strip away before repainting the original corvette gray.
#5
Race Director
Thanks for the replies... That cam is a bit on the high side as far as price compared to other ive seen. Not sure if I will be able to justify it to myself... I had to spend a lot on interior restoration and still have to tackle the body work.... two terrible paint job layers to strip away before repainting the original corvette gray.
#6
Safety Car
Thread Starter
Yes good point.... I noticed it was a roller cam. Is there anything else required for a roller over a flat tappet?.. The heads have the dual springs but I don't have the specifics on them.
#7
i'm doing the same type of rebuild on my L48 except with 64cc chev 186 heads, for the very stock look, roller tip rockers and a eddy performer manifold.
i entered my info into the comp cams web site, and they recomended the xe262h cam with the stock 2000 stall and 3.08 rear.
but othere have suggested i go one bigger to the xe268h. ??
i too am only looking to wake up the old girl and keep it drivable
i entered my info into the comp cams web site, and they recomended the xe262h cam with the stock 2000 stall and 3.08 rear.
but othere have suggested i go one bigger to the xe268h. ??
i too am only looking to wake up the old girl and keep it drivable
#8
Instructor
Member Since: Mar 2012
Location: Lancaster Pa
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i'm doing the same type of rebuild on my L48 except with 64cc chev 186 heads, for the very stock look, roller tip rockers and a eddy performer manifold.
i entered my info into the comp cams web site, and they recomended the xe262h cam with the stock 2000 stall and 3.08 rear.
but othere have suggested i go one bigger to the xe268h. ??
i too am only looking to wake up the old girl and keep it drivable
i entered my info into the comp cams web site, and they recomended the xe262h cam with the stock 2000 stall and 3.08 rear.
but othere have suggested i go one bigger to the xe268h. ??
i too am only looking to wake up the old girl and keep it drivable
#9
Team Owner
Member Since: Oct 2004
Location: altered state
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St. Jude Donor '05
A wiped lobe can take out every machined part on teh motor.
Youll need lifters springs etc. Yeah hard parting wiht the money but totally well worth it in the long run. More torque hp vacuum smoother idle than comparable cam specs in flat tappet.
They are the way to go.
Youll need lifters springs etc. Yeah hard parting wiht the money but totally well worth it in the long run. More torque hp vacuum smoother idle than comparable cam specs in flat tappet.
They are the way to go.
#10
Race Director
The valves on those are quite likely +.100 over stock so your probably buying new pushrods anyway. Check the seat and open pressure on the springs and installed height - coil bind height - .060 is max lift. If you don't have the tools or know how it is cheap at a good machine shop.
#11
Melting Slicks
I really like my thumpr cam. It sounds good, and gives a good performance upgrade (I have the 2nd from the bottom of the list) - I also have a higher stall converter.
I will warn, though, power comes on like a light switch at 3500 rpm.
I have holley sidepipes, and the quietest muffler they have - and it still sounds really good.
I will warn, though, power comes on like a light switch at 3500 rpm.
I have holley sidepipes, and the quietest muffler they have - and it still sounds really good.
#12
Safety Car
Thread Starter
I have a flat tappet air cooled VW kit car so I've been aware of the need for ZDDP in the newer oils to help prevent prevent wiping out the cam.... honestly I believe there is a bad lobe on the stock cam in this vette now one of the rockers was very loose and I have noise coming from the what seems like lifter area on that side of the engine there an exhaust leak as well that I have to fix before I can tell for sure. I'm still learning but the previous owner was a kid who knew nothing.... The horn stopped working for example and he used lamp cord to run a doorbell switch to end electric siren.... All the horn needed was a tap to knock the element loose and the horn button was assembled wrong.
#13
Melting Slicks
I have a flat tappet air cooled VW kit car so I've been aware of the need for ZDDP in the newer oils to help prevent prevent wiping out the cam.... honestly I believe there is a bad lobe on the stock cam in this vette now one of the rockers was very loose and I have noise coming from the what seems like lifter area on that side of the engine there an exhaust leak as well that I have to fix before I can tell for sure. I'm still learning but the previous owner was a kid who knew nothing.... The horn stopped working for example and he used lamp cord to run a doorbell switch to end electric siren.... All the horn needed was a tap to knock the element loose and the horn button was assembled wrong.
In my case, I can't believe how brutally easy it was to take the slug of an L48 and make it run hard.
I also run roller rockers - and they will back off a bit if you didn't invoke the right roller rocker saint when you tightened it down (St. Thomas - the saint of lost causes in case you need to know )
#14
Burning Brakes
Felpro 1094 head gasket.
This cam & lifter kit.
http://www.summitracing.com/parts/HRS-CL111145-10/
It will give you the sound you want and the operating range is perfect for your TH400 (it has a 2000 stall convertor stock) and 9.5 to 1 with iron heads. It will likely get you 25-30 HP over a comparable flat tappet with your heads.
This cam & lifter kit.
http://www.summitracing.com/parts/HRS-CL111145-10/
It will give you the sound you want and the operating range is perfect for your TH400 (it has a 2000 stall convertor stock) and 9.5 to 1 with iron heads. It will likely get you 25-30 HP over a comparable flat tappet with your heads.
#15
Race Director
#16
Safety Car
Thread Starter
Ok so a bit has changed since I started this thread and I could use more advice.
I ended up deciding to pull and store the original block mainly because I found a great deal on a 75 high nickel 4 bolt that was just bored 30 over and has 4 relief flat tops...with the 1094 felpros and dart iron eagles i estimate about 10:4 compression...I have also purchased an rpm style intake and am getting a holley750 carb...this should work with my obx stainless header/sidepipes....
My Struggle is still with the cam choice.... I dont have the funds to go roller.
I am considering the voodoo 60103 cam but am concerned about it being a dog with 3:08 gears and the auto..... I dont mind replacing the converter before the engine goes in the car but id like to get this engine together and the cam is holding me up....
I have a 268h cam and a small 12-600-4 thumpr but after researching them they are both not ideal for my 355 for efficiency from what I've read..
Any suggestions for a hyd tappet cam choice.... I like a somewhat rough idle but not if it comes at a cost in my application
I ended up deciding to pull and store the original block mainly because I found a great deal on a 75 high nickel 4 bolt that was just bored 30 over and has 4 relief flat tops...with the 1094 felpros and dart iron eagles i estimate about 10:4 compression...I have also purchased an rpm style intake and am getting a holley750 carb...this should work with my obx stainless header/sidepipes....
My Struggle is still with the cam choice.... I dont have the funds to go roller.
I am considering the voodoo 60103 cam but am concerned about it being a dog with 3:08 gears and the auto..... I dont mind replacing the converter before the engine goes in the car but id like to get this engine together and the cam is holding me up....
I have a 268h cam and a small 12-600-4 thumpr but after researching them they are both not ideal for my 355 for efficiency from what I've read..
Any suggestions for a hyd tappet cam choice.... I like a somewhat rough idle but not if it comes at a cost in my application
#19
Drifting
Do Your Homework!
I had the luxury of driving my car 50K before I decided what changes I wanted to make.
Then I did my research on other forum members and how happy they were w/cam and gear choice. Only you know how you drive and where you want power and what rpm you will cruise or race at.
Best advice I've heard from a pro:
Do all your research, make your best choice, then go one size smaller!
I added 1.6 RRs, cooler and quieter!
JMHO
R
Then I did my research on other forum members and how happy they were w/cam and gear choice. Only you know how you drive and where you want power and what rpm you will cruise or race at.
Best advice I've heard from a pro:
Do all your research, make your best choice, then go one size smaller!
I added 1.6 RRs, cooler and quieter!
JMHO
R