getting a camaro or firebird to bite


Staff member
one of my friends recently purchased a 1967 Pontiac fire-bird as a project car,
500 hp with a 400-455 Pontiac is VERY doable, its just not all that commonly done with stock parts,
Pontiac designed most of the more common , engine combos with heavy passenger cars and daily transportation, firm;ly in mind,
the original stock engines, compression, cams, heads etc, were selected to maximize torque in the 1500rpm -4500 rpm power band.
that in no way suggests the engines can,t be tweaked to produce impressive power

THIS INTAKE , Edelbrock Victor Intake Manifolds 2957 with the larger than stock 215cc port #60599 EDELBROCK ALUMINUM HEADS


cams like this, crane cam linked here,
if matched to a 428-455 with 10:1 or higher compression and mildly ported heads,
can produce impressive power in cars like a 1967 firebird with a muncie transmission and 3.55:1 rear gears
(but obviously new valve springs and checking clearances is mandatory)

yes theres a roller cam thats even better

it looks amazingly similar to this picture I found on the internet

a very noticeable improvement in launch and traction is easily available,
through the addition of traction bars, youll notice a very obvious improvement in the cars launch with either option, obviously carefully reading, before and following the instructions installing either traction aid is mandatory

two options the LAKEWOOD STYLE traction bars


LAKEWOOD STYLE traction bars normally cost between $70-$120 there not quite as effective but they work reasonably well. ... _21607.pdf
or the CAL TRAC TYPE bars






he had a 428 Pontiac engine , and a muncie 4 speed, sitting on his shop floor for several years looking for the right deal on a car to come along, (that I had done a basic rebuild job on several years ago ),and he eventually found the car at a good price,that had a decent body and interior and a blown up engine for sale, the car had 3.90:1 rear gears in a ford 9" rear differential, added by the previous owner,which were not ideal on a street Pontiac,but the price was good so he jumped on the deal,
the engine is where I did a minor port and bowl clean-up and cam swap (crane 105082) which has a 228/228 duration and a 480/480 lift on a 110 lsa, the engines about a 10:1 cpr , the result was that he could destroy tires easily but traction was a huge problem


In 1967 the 421 was bored to 4 1⁄8 in (104.8 mm), increasing its displacement to 427.6 cu in (7,007 cc). The 428 had the same 4.00" stroke as the 421, and was produced from 1967 to 1969. This engine produced 370 hp (280 kW), or 390 hp (290 kW) in High Output (H.O.) form. The crankshaft in the 428 also had a N cast on them as opposed to the 421's Armasteel. In 1969, Pontiac also used a revised crankshaft out of a Pearlitic malleable iron, although it still used the" N" casting letter. This new material had stronger alloys in the iron. All 428 engines were factory install in large cars only. However, there were a few dealers that would install a 428 in a customers GTO or Firebird for higher power levels.
a fairly heavy car,a decent engine and sticky tires will kill a 10 bolt rear differential, but I don,t think you'll have any durability issues with a 10 bolt G.M. differential with a posi unit, installed behind a 383 SBC , if you never install high traction tires or try to launch the car like I see all too many un-informed people do occasionally, by dropping it into gear or backing the car up to put slack in the suspension,and drive train, then flooring the car and dropping it into gear, or deliberately launching the car off wet or sandy pavement, before reaching dry surfaces,
from my perspective, after shredding, several 10 bolt differentials personally, just by applying BBC engine power,in passing or rapid acceleration,using decent racing type tires,and watching guys install serious BBC and similar high power/torque engines I've built into cars that very quickly did the same thing ,
I almost universally suggest anyone thinking of racing a car with decent tires strongly consider up-grading any 10 bolt G.M. differential to at least a 12 bolt, or better yet a ford 9", dana 60, 9.3" pontiac differential, or at least a 9.25" mopar differential. you only have too puke axles, loose a wheel, and shred ring gears a few times to have that bit of experience,brought home so you don,t forget it!
street tires generally act like a safety fuse they loose traction and spin, so the full shock loads don,t impact the rear differential, that certainly does NOT mean you can,t shred a 10 bolt rear differential with street tires it simply means its takes a bit more time and effort compared to having decent traction. ... il&p=23874

and added a much better intake manifold



THIS INTAKE , Edelbrock Victor Intake Manifolds 2957 with the larger than stock 215cc port #60599 EDELBROCK ALUMINUM HEADS and with a 750 cfm holley,HAS PROVEN TO WORK REALLY WELL ON MANY PONTIAC PERFORMANCE COMBOS WHERE IT FITS UNDER HOOD CLEARANCE
BTW IF YOU RETAIN THE STOCK CAM AND Q-JET CARB, or have an automatic transmission and 2.87:1-3.36:1 THIS INTAKE WORKS BETTER

this intake and carb when matched to a decent mid range cam,in the 225-240 duration range,usually produces a very noticeable improvement in power levels in most 389-455 Pontiacs engines once the heads are cleaned up and headers are added to use the increased flow they provide

I explained that he had two options the LAKEWOOD STYLE traction bars or the CAL TRAC TYPE bars


cal-track bars normally cost about $350, but you can, measure and fabricate decent cal trac bars if you have a welder and some basic machine shop skills, and understand the basic concepts involved,keep in mind most street rated tires are hopelessly useless in the pursuit of gaining consistent traction on a car with over 400 plus horsepower , the engine simply over powers the available traction, youll need a properly set up suspension AND decent RACING SLICKS to get power to the ground consistently.
yes, the addition of traction bars to the stock suspension, generally help's very noticeably, once you have good racing slicks or even some of the better street tires, they did on my 1969 big block (396- then later 496)camaro and on my 1967 400 and later 421) fire bird!

btw I rapidly learned about the 10 bolt differential and its lack of ability to take abuse in that fire-bird, once I tried slicks, and a correctly modified Pontiac engine, and the 12 bolt chevy rear differential only lasted a few months behind a 13.7:1 compression 496 once I added slicks.
both work, but on both my 1967 fire bird and my 1969 camaro the 60 foot times improved slightly with the caltrac traction bars over the lakewoods, and yes I swapped them back and forth a few times to compare times....your results could of course differ depending on your power and suspension and tires and obviously drive train gearing etc.
street tires act like a safety fuse that prevents the stock u-joints and differentials from the shock and torque loads a true high performance engine and properly geared drive train can transmit to the street tires, as they simply loose traction and spin, thus the full potential loads never get transmitted to the drive train with street tires.


my friend installed a used set of slapper bars he found on Craig's list for $50 , the results were a marked improvement but he still has traction issues if he forgets and just floors the throttle without thinking, hes learned that a slightly more gradual application of the gas petal allows the car to maintain traction now that the slapper bars are installed

IF I was designing it ID be using 1" or larger DIAM ,1/8" wall thickness MINIMUM chrome moly tubing and a MATCHED grade 8 OR BETTER, HEIM JOINTS and GUSSET the intersecting joints, and use a TIG WELDER ... &top_cat=0

heim1.jpg ... read/smc20?


17" & 18" rim size slicks are available



Id bet 40% of the members don,t know what those traction bars even look like or how they work, so for those members heres some basics


here are now 17" slicks available ....but a serious power level and a dana 36 combined won,t be a good combo with slicks

17" & 18" rim size slicks are available ... s_id=12401

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READ THIS ... assis2.asp


The bolt-on "Slapper Bar" is one of the most basic traction devices available. Originally pioneered by Bill "Grumpy" Jenkins in the mid-sixties, it gets its name from the way it works. One end of the Slapper Bar replaces the stock spring pad and is clamped to the rear axle housing. The front end of the bar is suspended just below the spring eye. When the housing begins to rotate during launch, the bar also rotates until it contacts or "slaps" the spring. (Unlike other brands, Competition Engineering Traction Bars make contact directly below the front spring eye, preventing spring damage). When contact occurs, the Slapper Bar becomes a lever trying to push the axle housing down and planting the tires in the process.


A revolutionary, patented, completely bolt-on traction device, the Slide-A-Link designed for both street and strip use is track tested and competition proven to outperform conventional â Slapper  bars. A solid mounted front plate is installed inside the original front spring pocket and clamps to the leaf spring to provide a positive displacement for the torque that is transmitted from the rear axle through the telescoping bar and special durometer shock pad. These forces, along with improved instant center geometry, provide better weight transfer for increased traction. Free travel and pre-load adjustments are made on the vehicle by adjusting the jack screw at the rear of the bar.

reading the links, and sub-links would not hurt a bit!
if youve tried both lakewood slapper bars then tried the CALTRACS youll see the difference in how the weight transfer to the suspension works, yes both designs have some adjustments, and yes both work, but try both and Ill bet you go with caltrac design bars
slapper bars basically limit spring wrap and differential rotation, caltrac use the force the differential rotation provides to redirect the energy info forcing the car weight down on the tires


LAKEWOOD STYLE traction bars normally cost between $70-$120 there not quite as effective but they work reasonably well. ... _21607.pdf

THERE ARE BOLT IN FORD 9" rear differential housings designed for fire birds and camaros ... 2380330902

I got asked why I prefer the dana 60 over the 12 bolt differential, well, I shredded my first stock 12 bolt in my 1969 camaro 375 hp 396 bbc,(yes it had slicks and a 13.7:1 compression, 496 BBC with crower injection,)
so I spent a great deal of cash on a new 12 bolt, and summers brothers axles a a spool, and supposedly stronger bearing and gears, this was back in the early 1970s
and keep in mind all those parts cost me almost as much as I could at the time buy a used 1969 camaro for ...
I had already installed traction bars , better shocks and leaf springs, frame stiffener extensions and a 4 point roll bar, and a much stronger set of u-joints a custom drive shaft, wheel studs, and yoke.
that very expensive differential lasted about 5 months... I swapped too a dana 60, I bought from a salvage yard from a wrecked car, that had a bad engine fire, out of a 1970 hemi cuda, and never had a single issue
here,s a picture of me in 1970 (47 years ago) with a 1969 camaro I installed a BBC-496 with a tunnel ram into, then later CROWER FUEL INJECTION



Now, I'm older, much more experienced, have a lot more tools, a better shop,
I've had 47 years to learn from almost 200, successful, engine and car builds,
and made my share of mistakes and learned from it all,
I'm bit heavier, and still wasting a great deal of money on cars,
and yes, it took me almost 40-47 additional years too get that far




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reliable source of info
Does his car still have the mono leaf springs that came on all '67's and the un-staggered shocks? If so, going to '68 setup with multi leaf springs/staggered shocks will make a world of difference.


Staff member
who ever swapped in the 9" ford rear swapped in multi leaf springs from a similar car, I think they may be custom made, or possibly 68-0r 69 camaro springs but its not original single mono spring leaf springs

related thread


Item: Years of Interchangeability:
Engine Block: 1955,1956,1957,1959-60,1961-64 (Full size V-8), 1964-69 (Tempest & Grand Prix V-8), 1970-79.
Bell Housings: 1955,1956-57,1958-60,1961-64 (Fullsize), 1964-79 (All but 1964 Fullsize)
Oil Pump: 1955-58, 1959-79
Oil Pan: 1955-58, 1959-60, 1961-63, 1964, 1965-71, 1972-79
Windage Tray: 1955-58, 1959-60, 1961-62, 1963, 1964, 1965-72
Oil Filter: 1955-59, 1960-1979
Oil Filter Housing: 1955-59, 1960-1962, 1963, 1964-1970 (Straight), 1967-1979 (Tilted)
Crankshaft: 1955-1956, 1957-1958, 1959-1966 (3" Main), 1967-1976 (3" Main), 1962-1969 (3.25" Main)
Harmonic Balancer: 1955-1962, 1963, 1964, 1965, 1966, 1967, 1968-1979
Flywheel: 1955-1957, 1958-1960, 1961-1962, 1963, 1964-1979
Connecting Rods: 1955-1979
Pistons: Must be the same as bore, stroke, & head series. **455 SD only fits with SD rods !!!
Wrist Pins: 1955-1957, 1958-1962, 1963-1965, 1966-1979
Rings: Interchangeable within same bore size except 455
Heads: 1955, 1956-1960, 1961-1966, 1967-1979
Rocker Arms: 1955, 1956-1960, 1961-1964, 1963 (421 HO)-1964 (GTO Tripower), 1965, 1966, 1967 (326 only)1967-1979
Pushrods: 1955-1960, 1961-1966, 1967-1976 (except Ram Air IV), ***Match pushrod to year of head
Valve Covers: 1955-1957, 1958-1960, 1961-1962, 1963-1966, 1967-1979
Lifters: 1955, 1956-1979
Camshaft: 1955-1959 except for Ram Air V & 455 Super duty
Intake Manifold: 1955, 1956, 1957-1958, 1959-1960, 1961-1962, 1963-1964, 1965-1971, 1972-1979
Exhaust Manifolds: 1955, 1956, 1957, 1958, 1959-1979 (D-port) 1968-1974 (Round port)
Distributor: 1955-1979 except for Ram Air V & 455 Super duty
Starter: 1955, 1956-1960, 1961-1964 (Fullsize) 1964 (Tempest & Grand Prix)-1979
Timing Cover: 1955-1959, 1960, 1961-1962 (Pontiac 8 & Tempest 4), 1963, 1963 1/2-1965, 1966-1967, 1968, 1969-1979 ... elect.html ... ucts_id=15

caltracks will cost you $260-$350 to buy
you can very easily fabricate a really nice custom set for about $100-$150 LESS if you have a welder tools and fabrication skills

now you can buy far cheaper traction bars but you need to compare prices with what your buying vs what you can fabricate in any design and in almost all cases youll find that saving 30%-70% is easily done IF YOU HAVE THE FABRICATION SKILLS AND TOOLS
pontiacegdis.png ... index.html ... index.html ... index.html ... index.html ... ssion.html ... index.html ... sheet.html



viewtopic.php?f=44&t=1154&p=17809#p17809 ... 20head.htm ... cu_in.html



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Active Member
I would have him check pinion angle and also get a good set of tires. No matter what he does to the suspension, if he's on a true street radial tire, it isn't going to hook at all. Just my .02.



Staff member
I recently had the fire-bird with the 428 Pontiac engine come back by and I took a ride to the local NAPA auto parts store to get the required parts for a tune-up, it was really interesting to see how this car responded to a tune-up, it went from a car that could easily smoke the tires only in first gear and part of second gear before the tune-up to a much more responsive car that easily smoked the tires up to at least 30-35 mph and most of the way thru 2nd ger with a health screech of tire tread on shifting into third gear.
even the guy driving it had forgotten how much better the engine ran when correctly tuned because the power loss had been very gradual, things like a better air cleaner, adjusting the ignition timing ,replacing the spark plugs and ignition wires, replacing the distributor cap , replacing a cracked leaking vacuum hose and setting the float levels and replacing the fuel filter all might have been over looked but each contributed to improving performance.
some of his spark plugs were gaped at over .060 thru wear and indicated a lean idle condition
heres some pictures from the spark plug thread that might prove useful



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