Radical 355
Le Mans Master
Joined: Apr 2000
Posts: 7,562
Likes: 9
From: B'Ville NY
Cruise-In III Veteran
St. Jude Donor '05
Drifting
Joined: Apr 2007
Posts: 1,892
Likes: 3
From: Springfield Illinois
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,444
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
My 355 ci was 10.6 or 10.7 C/R with way to much money into 64cc 186 double hump castings. -5 cc valve relief flat tops with the .015 steel shim head gaskets. Mallory Unilite vac dist. With the crane 278 powermax H-flat cam 1.6 roller rockers weiand single plane 750 edelbrock and demon 750 right before it went to crusher. I had that motor for about 10 years and 100.000 some miles. with a Hot rodded TH350 and 355 gears it was over 21 mpg on extended highway trips.
California only has 91 octane
California only has 91 octane
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,062
From: altered state
St. Jude Donor '05
Heres a cheapir combo that runs real good (did this one years ago)
350 .030 over
CAT forged rotating assy (balancer too)from speed-o-motive
Hyperutectic flat tops, 11:1 with 0 deck
Perfprmer RPM heads with some cleanup work. 1/6 rocker
Comp Solid flat tappet 244/252, .520/.530 lift 110
Team G (it wanted a 1" open spacer) or Performer Rpm, 750 D.P.
Had very little in this thing, car absolutely ripped. We laughed because it was such a cheapie backyard build and ran so good
Probably wouldnt recommend the hypers, a better head would make more power too but it was what it was. It sounded real radical but actually drove pretty well, made halfway decent torque and would flat out scream. 700r, 4.11 and 2800 stall.
350 .030 over
CAT forged rotating assy (balancer too)from speed-o-motive
Hyperutectic flat tops, 11:1 with 0 deck
Perfprmer RPM heads with some cleanup work. 1/6 rocker
Comp Solid flat tappet 244/252, .520/.530 lift 110
Team G (it wanted a 1" open spacer) or Performer Rpm, 750 D.P.
Had very little in this thing, car absolutely ripped. We laughed because it was such a cheapie backyard build and ran so good
Probably wouldnt recommend the hypers, a better head would make more power too but it was what it was. It sounded real radical but actually drove pretty well, made halfway decent torque and would flat out scream. 700r, 4.11 and 2800 stall.
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
Building a 355 IMHO is generally a waste of $$$ given that it's pretty much a financial wash with a 383. If you're going to build one that's really rowdy, you're already into a forged rotating assy...so why not pick up the extra cubes?
Doesn't mean that a hot 355 isn't a fun engine
- but in terms of cubic dollars there are better choices.
I've built a couple of all forged 355s that saw north of 7K RPM...and they were a riot just because you usually don't hear them going that high One of them was a near-spec 1970 LT-1 that I had originally intended to build for myself, the other was an RHS 200cc head solid roller cam (retrofit) with a rev kit. Neither were engine dyno'd, and I didn't get any performance specs from the owners afterwards :/
Doesn't mean that a hot 355 isn't a fun engine
- but in terms of cubic dollars there are better choices.I've built a couple of all forged 355s that saw north of 7K RPM...and they were a riot just because you usually don't hear them going that high
One of them was a near-spec 1970 LT-1 that I had originally intended to build for myself, the other was an RHS 200cc head solid roller cam (retrofit) with a rev kit. Neither were engine dyno'd, and I didn't get any performance specs from the owners afterwards :/
Last edited by billla; Dec 6, 2008 at 09:36 AM.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,062
From: altered state
St. Jude Donor '05
Neither were engine dyno'd, and I didn't get any performance specs from the owners afterwards :/
Last edited by cv67; Dec 6, 2008 at 01:34 PM.
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
Well, for a lot of guys it's about getting the engine in the chassis as soon as possible
I don't do "professional" builds (i.e., I don't and don't try to make a profit) and so it's all friends or friends of friends. And the vast majority are what I'd consider performance overhauls vs. full designs.
I don't do "professional" builds (i.e., I don't and don't try to make a profit) and so it's all friends or friends of friends. And the vast majority are what I'd consider performance overhauls vs. full designs.
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Thread Starter
Team Owner
Joined: Apr 2002
Posts: 62,198
Likes: 1
From: All humans are vermin in the eyes of Guru VA
Cruise-In IV Veteran
Cruise-In V Veteran
Here is my cammotion camshaft.
Grind Number S2461-2531-10+4
Duration (intake/exaust) 246/253
Lift (intake/exaust) .560/.541
Lobe Center Separation 110
Intake Centerline 106
Comments valve lash .024 on int. and exh.
Price US$$177.00 + frt.
Grind Number S2461-2531-10+4
Duration (intake/exaust) 246/253
Lift (intake/exaust) .560/.541
Lobe Center Separation 110
Intake Centerline 106
Comments valve lash .024 on int. and exh.
Price US$$177.00 + frt.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
Very nice intake lift.
Last edited by Little Mouse; Dec 8, 2008 at 04:08 PM.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,444
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Heres a cheapir combo that runs real good (did this one years ago)
350 .030 over
CAT forged rotating assy (balancer too)from speed-o-motive
Hyperutectic flat tops, 11:1 with 0 deck
Perfprmer RPM heads with some cleanup work. 1/6 rocker
Comp Solid flat tappet 244/252, .520/.530 lift 110
Team G (it wanted a 1" open spacer) or Performer Rpm, 750 D.P.
Had very little in this thing, car absolutely ripped. We laughed because it was such a cheapie backyard build and ran so good
Probably wouldnt recommend the hypers, a better head would make more power too but it was what it was. It sounded real radical but actually drove pretty well, made halfway decent torque and would flat out scream. 700r, 4.11 and 2800 stall.
350 .030 over
CAT forged rotating assy (balancer too)from speed-o-motive
Hyperutectic flat tops, 11:1 with 0 deck
Perfprmer RPM heads with some cleanup work. 1/6 rocker
Comp Solid flat tappet 244/252, .520/.530 lift 110
Team G (it wanted a 1" open spacer) or Performer Rpm, 750 D.P.
Had very little in this thing, car absolutely ripped. We laughed because it was such a cheapie backyard build and ran so good
Probably wouldnt recommend the hypers, a better head would make more power too but it was what it was. It sounded real radical but actually drove pretty well, made halfway decent torque and would flat out scream. 700r, 4.11 and 2800 stall.
Race Director
Joined: Apr 2000
Posts: 17,665
Likes: 194
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Build it and see, I built a solid roller motor with top notch 220cc 23 deg aluminum heads and a cam with 250 duration ,620" lift with 406ci, 11:1 cr to get that kind of HP, maybe I should have just built a flat tappet 355ci 
Thread Starter
Team Owner
Joined: Apr 2002
Posts: 62,198
Likes: 1
From: All humans are vermin in the eyes of Guru VA
Cruise-In IV Veteran
Cruise-In V Veteran
I did say if you believed that sorta thing... I am skeptical.
If you believe these sorts of things this is what DD2k says about your 406 best I remember it.
If you believe these sorts of things this is what DD2k says about your 406 best I remember it.
Last edited by Guru_4_hire; Dec 8, 2008 at 09:41 PM.
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
I was more than agnostic, but I came up with similar numbers in DD Advanced/Pro Tools: 539FWHP@6500 RPM and 480FWTQ@4500-5000RPM. I honestly can't see it from the specs...but The heads are pretty decent - 261/172 flow @ .500 and the cam is pretty healthy too.
It's worth noting this is with large tube headers and open exhaust - big engine dyno numbers :/
It's worth noting this is with large tube headers and open exhaust - big engine dyno numbers :/
Pro
Joined: Dec 2006
Posts: 665
Likes: 0
From: wilmington nc
Guru, this may be of interest to you, looks like a similar engine to what you have in mind.
http://www.chevyhiperformance.com/te...ild/index.html
http://www.chevyhiperformance.com/te...ild/index.html
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
I see they used a 220 runner head, a cam with more duration even if the lobe centers were narrow.
I had an article in one of the rags I sent the whole magazine to ratflinger when he was considering dart heads for a 383/396, anyway this was before dart came out with the platinum iron heads, they tested all five of darts iron heads 165,180,200,215,230 runners on a 355, 10.0 comp. Considerable less cam then guru is going to use, edelbrock dual plane holley 750 carb. The people writing the article were expecting the 180 runner head to be the best match, after the testing the 215 runner head made the most power not just at the upper HP limits of the engine, the most overall power across the intire power band of the test, even the 230 head came in second in overall power.
I had an article in one of the rags I sent the whole magazine to ratflinger when he was considering dart heads for a 383/396, anyway this was before dart came out with the platinum iron heads, they tested all five of darts iron heads 165,180,200,215,230 runners on a 355, 10.0 comp. Considerable less cam then guru is going to use, edelbrock dual plane holley 750 carb. The people writing the article were expecting the 180 runner head to be the best match, after the testing the 215 runner head made the most power not just at the upper HP limits of the engine, the most overall power across the intire power band of the test, even the 230 head came in second in overall power.
Last edited by Little Mouse; Dec 9, 2008 at 01:29 PM.