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67rally
02-07-2012, 05:59 PM
Hey guys, I posted this over on TC as well, but looking for all the advice I can get...

Looking for a few opinions on carburetor, camshaft, etc. for a spirited street car (67 Camaro).


I just picked up a clean used set of Vortec 906 heads (assembled w/valve springs, self aligning rocker arms) with a Edelbrock Vortec RPM intake and am looking for some suggestions. My current engine is a bit of a dog. It is a very stock 350, casting numbers 10054727, '87-'95, center bolt valve covers, non-vortec, summit racing headers, and an Edelbrock 1406 600cfm carb. 4 spd Saginaw, 3.31's 12 bolt posi.


I'd like to keep the heads the way they are...I'll be installing the new heads and intake sometime in the next couple of months, and it just needs to hold me over for a year or two when I do a 500+hp LS swap.


Will my 600cfm Eddy be enough? Or would the 650cfm Edelbrock AVS be a better fit? Would the 800cfm Edelbrock AVS be too big? If I buy a new carb now, it needs to be sufficient for the LS swap as well.


Thoughts on cam selection? I don't believe this block is setup for a roller cam...So, stick with the stock one for now? Hydraulic flat tappet? Lunati? Comp Cams? 262? 268? Thanks.

shmoov69
02-07-2012, 09:53 PM
Here's a combo that I had before the turbos. Not a monster, but a killer street engine that ran pretty hard and sounded even better
Chassis dyno'd 325hp/425tq on a dynojet dyno.

355 ci
.125 dome pistons
Mild port work on the vortec heads
Performer RPM intake
Holley 650 puddle dumper
Lunati 232@50 duration 510 lift flat hyd cam

If I remember correctly, I got it to run mid 12's in the 1/4 with 3.70 gear in my 69.....but that was awhile ago!

Good luck

SLO_Z28
02-07-2012, 10:06 PM
The comp XE268H is the most cam you can fit in there with stock springs. A 10:1 engine with a 650 carb and edelbrock RPM air gap makes north of 400hp and 450# at the flywheel.

67rally
02-08-2012, 02:51 AM
The comp XE268H is the most cam you can fit in there with stock springs. A 10:1 engine with a 650 carb and edelbrock RPM air gap makes north of 400hp and 450# at the flywheel.

Is that cam pushing the limits of lift, or will it be ok? I'd rather go with a 268 if it will work, but would drop down a size the 268 isn't a 100% fit. I would be very happy with anything close to 400hp on this motor. I was thinking mid to high 300's would be good.

SLO_Z28
02-08-2012, 04:44 AM
Is that cam pushing the limits of lift, or will it be ok? I'd rather go with a 268 if it will work, but would drop down a size the 268 isn't a 100% fit. I would be very happy with anything close to 400hp on this motor. I was thinking mid to high 300's would be good.

It will be OK. GM advertised the stock springs are good to .480, and the XE268H has a little more than that, but I know of many engines that have that combo and are OK years later. The engine is good for high 12's in a properly prepped car, so it has plenty of grunt.

67rally
02-08-2012, 05:27 AM
It will be OK. GM advertised the stock springs are good to .480, and the XE268H has a little more than that, but I know of many engines that have that combo and are OK years later. The engine is good for high 12's in a properly prepped car, so it has plenty of grunt.

That's very good news.

How do these compare to the Lunati cams? It looks like Lunati's 60103 268/272 has too much lift .489/.504 but their 60102 262/268 would work with lift .468/.489. But what about performance?

TT302Z28
02-08-2012, 05:46 AM
Be sure the bottom of the spring retainer doesn't hit the guide. The retainers get really close to the guide at .480 lift even if the springs are rated.

SLO_Z28
02-08-2012, 04:35 PM
With the amount of support that Comp gives to racers, and the level of quality and technical support, I pretty much only look at them for camshafts. I cant really speak to the lunati either way. It doesn't work any more but I used to have a dyno sheet of a 350 with hyper pistons (5cc), vortec heads, XE268H, Eddy RPM Air Gap, 750 holley SA, 1-5/8ths full length headers, flowmaster super 40's, and a TH350 making 321hp at 5800rpm at the wheels. Ive contemplated this as an engine build several times, you can build this using 100% new components for around $2500.

GMPP makes "performance spring kits" that are relatively cheap. You could order those and have the valves cut and some exhaust work done on the heads at the same time by a machine shop. That would open up more cam options too, and id bet you could find power up to the 272 range with ~520 or so.

For carb I would stick with a 750 Holley like the 0-80770, its a 770 street avenger with electric choke and vacuum secondarys, and a capable carb for performance while not losing streetability.

shmoov69
02-08-2012, 07:01 PM
BTW- I did have to cut the guides and pockets down on the heads to clear the lift. But now I got a .600 lift with vortec heads with no issues.

makoshark
02-08-2012, 07:10 PM
The 600 cfm carb you mentioned will be plenty of carb for that motor. I personally would run a 650 DP for a little better throttle response, but what you already have will work perfectly. DO NOT go any bigger. A 750 would be a pig on a street motor.

eldogg
02-10-2012, 07:12 AM
Check out the GM Performance HOT cam. You have a block that will accept OE roller cams. Take advantage of it. I have built 2 Hot cam 350's and it just flat works. Chevy High Performance did a build with one. http://www.chevyhiperformance.com/techarticles/49083_inexpensive_roller_cams/index.html
Thats whats in project Eldogg and has been bulletproof for almost 10 years now.

67rally
02-11-2012, 05:26 AM
Check out the GM Performance HOT cam. You have a block that will accept OE roller cams. Take advantage of it. I have built 2 Hot cam 350's and it just flat works. Chevy High Performance did a build with one. http://www.chevyhiperformance.com/techarticles/49083_inexpensive_roller_cams/index.html
Thats whats in project Eldogg and has been bulletproof for almost 10 years now.

I'm not sure my block will accept a roller cam. I have only seen one site that says it will. The rest of the sites I have seen reference my block (10054727) as a non-roller block, or don't indicate one way or another. If it turns out to be a roller block, I will definitely use a roller cam, but won't know until I tear it down.

SLO_Z28
02-11-2012, 10:28 AM
I'm not sure my block will accept a roller cam. I have only seen one site that says it will. The rest of the sites I have seen reference my block (10054727) as a non-roller block, or don't indicate one way or another. If it turns out to be a roller block, I will definitely use a roller cam, but won't know until I tear it down.

Thats the "K" truck motor. It will take roller cams. That GM Hot Cam, and the lingenfelter cam are both good options too.

67rally
02-11-2012, 01:54 PM
Thats the "K" truck motor. It will take roller cams. That GM Hot Cam, and the lingenfelter cam are both good options too.

That would be great if it does. Do you know for sure?

I posted over on TC and got mixed responses. The replies said that some blocks are set up for roller cams, some have bosses that may need to be drilled for the spider, and some of the blocks didn't even have the bosses cast into them.:dunno:

67rally
02-11-2012, 01:59 PM
Here's a quote from another site that I found:

"The casting numbers here are for production blocks manufactured from 1986 to the end of GenI/GenII production.

For 350 flat tappet blocks look for casting number 10054727, 14079287, 14088548, and 14101148.

Roller blocks are more complicated because even though the casting number indicates the block is provisioned for a roller cam, it doesn't for sure mean the block has a roller cam. But if so provisioned, a factory roller cam can be installed to one of these even if it currently has a flat tappet cam. For 350 roller tappet blocks look for casting numbers 10243880,14011148, 14088526, and 14093638 these can be a 2 or 4 bolt block. The 880 is the Vortec block it appears in mid 1995 production with swirl port heads and TBI and may have a flat tappet cam but is fully provisioned for a roller in all instances. It appears again in some 1996, 49 state vehicles with Vortec heads and TBI."

67rally
05-05-2012, 12:31 PM
Just a quick update. I pulled the heads and intake off my motor, and will be replacing them with a set of Vortec heads with LS6 beehive springs, and an Edelbrock Performer RPM intake. I'll be swapping in a new cam at the same time (not sure which one yet).

The block I have #10054727 is not a roller block. Even though it is an '87-'95 block, there is no provision for a roller cam. There are no bosses in the valley, no spider, nothing.

69X22
05-05-2012, 03:06 PM
http://www.chevyhiperformance.com/techarticles/67838_budget_vortec_head_cam_355_build/index.html
This is the one I have in my 57 and it runs like a scalded ass ape. Doesn't sound real radical but it runs awesome. I agree about the guides needing to be cut down, you need to elongate the pushrod holes and install screw in studs.

67rally
05-05-2012, 03:26 PM
I can't use a roller cam. It's not a roller block, that's why I asked about the retro-fit roller cam in my other thread.

68TTT
05-05-2012, 05:34 PM
I just pulled my vortec headed 355 out, I used the comp xe268 in it but I had the heads worked to take the larger valve springs. With an air gap intake and a 650cfm edelbrock it ran great. I later put a speed demon 750 on it and I felt like I lost a little of the bottom end but it felt better in the upper rpms, given this was a street car I wish I had just put a better 650cfm carb on it.

musclecarmatt
05-05-2012, 05:41 PM
i'm running the "906" heads on my 357 SBC Gen 1 motor.....got them ported intake/exhaust,3 angle valve job,hot cam spring/retainer kit which takes up .525 lift....will outflow GM fast burn heads.....i got comp cam magnum 270,edelbrock RPm air-gap,custom tuned holley 650 street hp...it pulls and revs up amazing...