Vortec CT350 crate in a street car.

[ClassicRob]

If someone gave you a smoking deal on a new CT350 crate, what would you do to it to make it run better? This is going in a 2nd gen Camaro with a 4 speed and 3.73's.

I would love to eclipse the 400-425hp mark with a 4150. How much cam? I know there are many circle track guys who know these things well... The problem is getting them to spill the beans. I am not a circle track racer. I am simply wanting to optimize the little 350 for street usage so you can forget any rule book.

This is what I am going to use until my vintage small block is done (whenever that will be)

[BOOT]

I've always herd vortec heads will support like 400+ unported, so the right cam and supporting parts(ie exhaust), there are plenty of vortec builds to research. I wouldn't worry to much what the circle track guys do, your car will be heavier, normally operate at a lower rpm and as you said your not held to any rules.

I know some will advise you to at least pull the heads and use a thinner shim gasket to raise compression, then it depends how handy you are with a grinder.

edit: changed the HP unported, I've read multiple diff but 400+ just seems like a safer estimate

[jred]

firc stock vortec's can only have about .440 lift the retainer hits the top of the guide or spring go into coil bind can't remember ,,

[1980RS]

If someone gave you a smoking deal on a new CT350 crate, what would you do to it to make it run better? This is going in a 2nd gen Camaro with a 4 speed and 3.73's.

I would love to eclipse the 400-425hp mark with a 4150. How much cam? I know there are many circle track guys who know these things well... The problem is getting them to spill the beans. I am not a circle track racer. I am simply wanting to optimize the little 350 for street usage so you can forget any rule book.

This is what I am going to use until my vintage small block is done (whenever that will be)

That's easy, Find the Elgin line of hyd cams for a SBC, there is one that's .480 lift with a 108°lca that should work, put some better valve springs in it, RPM Performer or Air Gap with a nice set of 1 5/8" headers, should make over 400hp.

[F-BIRD'88]

Use Isky "Z-27" Street strip solid cam cam 201027. Z-27. Use the GMPP LS6 behive valve springs #12499224 + Comp 787-16 retainers.
Shim the springs for 120 seat pressure.
Approx installed height 1.70 to 1.72"
Use stock rockers but check rocker to stud clearance at full lift . Grind the stock rocker slot longer as required.
Not wider.. The guided type rockers are fine Use a round wire feeler guage or a Pin .016" to set lash..
ISKY Z-27 282/282. 247/247@.050" .507/.507" lift
108 LSA 104/112 .
Do not use the stock springs.
Check to comp 787-16 retainer to valve seal clearance at full net valve lift. (.491" net w lash) should be plenty but check.

Must recurve the diz.. Either lock out or mod for a short 10 deg mechanical adv curve.. 26+10=36.

Best to replace the head gaskets with shim .015" gasket while the heads are off for spring set up.
It will GLH.

[dynoflo]

put bullet cam # 278 285 08h.sn585232 with delfi lifters and new gm valve springs and locks. call alexs parts and get new racing valves. It will make 400hp 400 tq. Done a bunch and you wont pull studs. Will go 6300 no problem. Doesnt require ghetto grind and screw in studs. degree intake to 102. The guided rockers will work with stock pushrods. Run stock head gaskets as cam works for lower compression very well on pump gas. dont go over 32 degrees timing and it will live a long life. I will probably get a lot of flack but believe me it works. KISS (keep it simple stupid)

[F-BIRD'88]

If you'd rather just use a simple Hyd flat tappet that bolts in and makes 400+ hp in that motor, a Isky cam #201278
gets it done very nicely..
278-278 234/234 @.050" 106 LSA 102/110. .450"/.450" lift..
Can again use the gmpp beehive springs (shimmed for seat pressure + the comp 787-16 retainers..
Or you can use any stock diameter Z/28 type high perf spring (.550" lift type) such as Summit or Elgin etc and just remove the inner damper to install.
Stock vortec retainers.. stock seals, stock rockers.
Its only .450" lift..
This cam gets er done in this motor.
Again if you want more CR change the head gaskets to .015" shim type and go..

400+ hp. great torque curve..

With either of these Isky Cams in your crate motor
I bet you'll be in no hurry for your nostalgia motor

[dynoflo]

I fotgot to mention that the intake on the crate works very well. I had egts on the last one on the dyno and they were all very close with a stock 650 dp. KISS works very well on these engines. 1 5/8 headers work well with oddball 2 3/4 inch collectors. Keep your tubes around 34 to 36 long. The tip about distributor timing is right on. Just remember max timing is 32 degrees.

[F-BIRD'88]

My vortec head motor runs best at 35-36 deg ..
The diz is locked out so it retards a bit itself at higher rpm. Could be at/near 32 deg at high rpm.

You can play with that +/- yourself At the track to dial your car in.

[ClassicRob]

I really want to keep this simple. Alex’s HFT kit looks good, as the beehives from comp are roller springs. 246 duration seems like it would be too big? I was thinking 280H max… but I’m open to others. I appreciate the feedback. I have never done a vortec deal despite all its popularity.

[ClassicRob]

Need to get compression up some

[F-BIRD'88]

There is no such thing as "roller springs".
The gmpp behive springs with the comp 787-16 retainers are your best bet.
You can lead a horse to water but you can't make em drink.

[1980RS]

There is no such thing as "roller springs".
The gmpp behive springs with the comp 787-16 retainers are your best bet.
You can lead a horse to water but you can't make em drink.

Or, you can lead a guy to HP but you can't make him use it.

[ClassicRob]

There is no such thing as "roller springs".
The gmpp behive springs with the comp 787-16 retainers are your best bet.
You can lead a horse to water but you can't make em drink.

Roller cam spring pressures… ie, very hard on a smaller FT lobe.

[BillK]

To be honest with looking at the specs in the GMPP catalog I would put it in just like it is. With the 3.73 gears it will probably be more than you will ever need. Save the money for your traditional build

Just my opinion,