View Full Version : 6 cyclinder performance


Dano
Jul 8th, 02, 03:44 AM
I believe that the early camaros came out with straight 6 cylinder engines. If so, as a change of pace it would be neat to hear what performance results people have with that engine.

Eric68
Jul 8th, 02, 04:01 AM
I think most people have swapped their turbothrift 6 bangers for a small block. I still have my original 250 I6 sitting in the garage and always wondered what a turbo would do for it. http://www.camaros.net/forum/biggrin.gif

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68 Camaro with 383 small block. ET - 11.9's at 112 mph and never trailered.

The combo:

10.3:1 KB pistons, Eagle cast crank, 5.7" SIR rods.
Trick Flow 23* heads ported 2.055 intake, 1.6 exhaust.
Comp Cams 282s mechanical cam with 1.6 rockers.
Victor Jr intake and Holley O-3310 carb.
1-3/4" Hedman Headers, full length Flowmaster exhaust.
TH350 trans, 3000 stall, 3.55 gear.
CE subframe connectors, drag shocks, SSM lift bars.

boodlefoof
Jul 8th, 02, 05:00 AM
www.cliffordperformance.com (http://www.cliffordperformance.com)

pdq67
Jul 8th, 02, 08:13 AM
Ditto Boodle. pdq67

Georgia_Gearhead
Jul 8th, 02, 09:45 AM
I built a 250 in 1980 using pistons from a 283/307 (same bore) Clifford headers and an Offenhauser intake with a Quadra-Jet. Put a 4-speed Muncie behind it. Used the hottest hyd. cam available and dropped in an HEI. Got sub 6 second 0-60 and over 150 top end with 3.21? gears. The trick is that inline engines make more torque ( proportionaly) than a V does. It's also coming in @1200-1500 RPM lower than the V. Ran like a scalded dog and would get 18+ mpg when not standing on it. HOWEVER, there are harmonics problems encountered that make it difficult to keep the flywheel on and will cause the balancer to shear sooner or later. But when it was running I blew the doors off more than a few big blocks and a stock SBC didn't stand a chance against it. Was in the low 13's and may possibly have had @170 top end (don't know for sure, didn't have any buddies with a 160 speedo back then). This motor can be really hot but does suffer from internal harmonics. Maybe some co. makes a fluid dampner for it now, it is necessary for longitivity. Do not use a HV oil pump! As a matter of fact, I'm going to do a search for a dampner to see if one's available now. You should see the look on people's faces when you open the hood after shutting them down. Yes, there is a replacement for displacement! Remember, torque is what moves your car, not horsepower. Also, Pontiac had an OHC version of the 250 but I've never managed to locate one. Imagine an aluminum DOHC engine with turbo and NOS and plenty of room in the engine bay to work on it! Also, the new generation inline is an aluminum engine with 270 HP. Add that to a 1st gen. and consider the weight differential and you can see that not only would you have good performance engine-wise but also wind up @ 3000 lbs. without having to strip anything from the car. That should make the basis for a hellacious G-machine that would be really unique as well!

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Steve

pdq67
Jul 8th, 02, 02:11 PM
Georgia is right.

A 261 to 300+ cubic inch Gimmy six hot-rodded was hard to handle back in their day!!

Heck, even today!!

The modern eq. is the long stroke 292 six truck engine! A very good engine but it can't be rpm'ed like the shorter stroke 230 and 250 versions! Just build the sucker for upper midrange (say 3000 to 5500rpm) torque and GEAR ACCORDINGLY!!! pdq67

MCGOO
Jul 8th, 02, 03:13 PM
DANO;

I've added a Clifford intake & header, with an Edlebrock 500 cfm carb, to my 250.

There is a significant increase in power, but not enough to keep up with a 327 that has the same changes. I think that my car could keep up with a bone stock 327 2bbl Camaro.
The fuel economy has improved. (if I keep my foot out of it.)

A lot can be done to the inline 6 to increase performance. If you have a Camaro with the 6 still in it I recommend keeping in the car just 'cause it is different. (It's amazing how many people have never seen a Camaro with an inline 6)

Check out Clifford Performance & inliners International.

Paul http://www.camaros.net/forum/cool.gif

Hey Georgia Gearhead; There is a balancer available from fisher. It is in the Clifford catalogue, & i've heard good things about it.
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250 inline 6, 4 speed & disc brakes.
V8 camaros are like navels.... Everybody has one.
www.geocities.com/pdmcgurran/My_camaro_pics.html (http://www.geocities.com/pdmcgurran/My_camaro_pics.html)

[This message has been edited by MCGOO (edited 07-08-2002).]

cavemanmoron
Jul 8th, 02, 05:05 PM
is clifford performance the same as Clifford's Research???
http://www.camaros.net/forum/smile.gifToday, Clifford Research, now known as Clifford Performance, is the undisputed leader in 4 & 6 cylinder cars and off-road vehicles.
I guess so! the link works Nice!!
I used to have a '65 Valiant 225 slant 6\
they made a 4 bbl intake headers etc....

[This message has been edited by cavemanmoron (edited 07-08-2002).]

Georgia_Gearhead
Jul 9th, 02, 10:45 AM
I didn't mention in my first post that I had also bumped compression to 10-1. Makes a lot of difference all by itself! pdq (and anyone else interested) the 292 must be used with auto or hyd. clutch as the mounting boss for clutch linkage is farther back on it. Paul, thanks for the tip, either I missed it or the balancer wasn't available last time I checked Clifford.

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Steve