Heads--including Edelbrock's popular aluminum castings--interchange. The Pontiac 350 engine was a great choice for drivers looking for a reliable engine with plenty of power. If youre looking for the best in Pontiac engines, look no further than DCI Motorcars. Pontiac V8 Engine Bore Sizes. The 60-psi Ram Air IV pump driven by a heavy-duty pump driveshaft is sufficient if you control bearing and rod side clearances. The cars engine was a 400 cubic inch (6.6 liter) V8 with large valve heads ($48s), and it was rated at 330 horsepower (246 kilowatts). From 1959 on, engines displacing between 326 and 400 inches contained a main journal diameter of 3 inches, while 421-, 428-, and 455ci engines featured 3.25-inch journals. Posts made up 1,398 of the total. A Pontiac 350 can be bored up to 4.155", which is a 0.060" overbore from the standard 4.095" bore size. We Were Wrong on the 2024 Camarobut at Least We Weren't Idiots About It! When the same head is used, it works better if nine out of ten times the overbore is used. A quench pad is available for the 4X and 6X heads of the Pontiac. Many numbers were available. I would say 300 horse is easy on a 350 Pontiac. How To Bore Out A Pontiac 350 V8 For Increased Power - OsVehicle Stock Pontiac 400 Specs: 400 standard bore is 4.120, stock stroke is 3.750, stock rod length is 6.625, stock wrist pin size is .9805. The 1968 Pontiac Firebird 350-cid HO V-8 engine, with high-performance camshafts, better exhaust gas scavenging, and revised carburetion, produced 320 horsepower, 35 more than the original 326-cid engine. I will find out what the cylinder heads and machining costs. Engine block and cylinder heads were cast at Saginaw Metal Casting Operations then assembled at Tonawanda Engine before delivery to Pontiac Assembly for installation. If there is evidence of burned or over-temped valves, it is required to pull them. Stock Stroke. So far, it seems that the 350 has a smaller bore, but the 400 and 455 share the same bores, but different strokes. A stock 1969 350HO was rated at 325hp. Boring and honing should always include a honing plate. HOT ROD Captures the World of Racing: 1968 in Photos. This will also allow you to accurately measure the bore size before and after boring. Beginning in 1968, Pontiac located the block casting number on a ledge just rearward of the No. All Pontiac V-8s have the same size and weight, ranging from 287 to 455 pounds. It is safe to bore all 350s with a hole of 0.060-over. If properly prepared, bottom end iron cranks can handle anything thrown at them. Its worth noting that the Pontiac Astre comes in a 2.2 L 17% silicon block. Most Pontiac blocks from 1970 forward have four or five engine-mount bolt holes on each side, which allows easy installation into any chassis. A few manufacturers now offer Pontiac-specific solid lifters that are internally restricted, lessening the need for this modification. The wider journal also compromised main saddle rigidity. Boring the cylinders larger than this can cause problems with piston-to-wall clearance, piston ring seal, and ring end gap. Ill be using some of the high compression small valve heads from my previous project, and Ill also be converting my project to use screws. Loose-fitting plugs sometimes push out when exposed to very high oil pressure, and that can result in a massive internal oil leak. A cast crank capable of 650 HP will last for many years. Why do the 350 HOs have a compression ratio of 10.5 to 1? 8 cylinder. Safe to bore 400 60 over? | Pontiac GTO Forum Those looking for a reliable engine that was both powerful and efficient could find it in this vehicle. It was the successor to the Pontiac 455 engine, and it was identical to its predecessors power and dependability. Enabling new startups in the electric and hybrid vehicle industry, Find Out Average Car Insurance Costs For A Pontiac. The block would not be removed. In the engine, the Total Seal gapless top rings, cast-iron second rings, and thin but standard-tension oil ring assembly are all used. I believe my transmission and rear end will be unable to handle it. The 7.5 rear end is a serious issue for the third generation. Leave it alone. Safely Connecting the Ground Wire to Your Car Battery, Cars with Batteries in the Trunk: Exploring the Benefits and Models, Your Roadmap to Buying a Used Car: 5 Essential Tips You Cant Ignore, When Your Car Battery Clicks: Understanding the Issue and Potential Solutions. The main bearing caps are fastened to the block by two large bolts in most instances and located by dowel pins to prevent the caps from wandering during high-speed operation. Those looking to improve their 350 small- block engine 's performance should avoid the 305 . When V-8 engines were first invented, they created an unprecedented amount of power in a street car. Nothing could be done about mileage. Generally measuring somewhere near 38-inch thick, it can be machined liberally without worrying about compromising its integrity. Might be a bit of a problem getting a cammed up motor to pass emissions. Solid lifters do not require it, and that can require the installation of lifter-bore restrictors that limit oil flow. Something to think about though. Light Em Up: Drag Racing, the HOT ROD Power Tour Way, Bottom fill with block filler, thermal clean, bore and hone with torque plate, line hone mains with studs, surface to zero deck, 428 Tomahawk Performance Products crankshaft, 3.00-in mains and BBC 2.200 rod journals, Professional Products Powerforce Elastamer, 6.800-in, Tomahawk Performance Products Ultra-Lites, 756g, King HP series rod bearings std, King AM series main bearings std, Tomahawk Performance Products, 3/4 stock type, Ishihara-Johnson, Zero-Tolerance Teflon, dual sides, 10540 Melling Select High Performance, 60 psi, 3/4 pickup, Tomahawk Performance Products Rocker Shafts System, 1.6:1 roller, S/A 9 Keyway true roller with removable bronze bushing, Tomahawk Performance Products, single-plane, Dyno/ACCEL Graphite for no computer interference. In 1964, the engine produced a respectable 280 horsepower as a result of a high output of 326 and a 4 barrel carburetor. The most you can bore a 350 is 4.000 inches. Those looking for power and performance were drawn to the 455, which was a fantastic engine for the time, but it was the best engine for those seeking power and performance. There would be more blocks to find. It employs the same 6.725-inch center-to-center Pontiac rods as the big motors, resulting in a fantastic 1.77:1 rod/stroke ratio. The head of a 1970s cylinder can be milling as small as 0.0600 inch in the most ideal conditions. So, if youre looking for the best in Pontiac engine building, look no further than DCI Motorsports. With today's long-stroke aftermarket crankshafts, a total displacement near 500 ci using a stock block is quite possible. It fits '64-'72 LeMans/GTO models and '67-'73 Firebirds. It is possible to bored all 350s with a speed of 0.040-over. Ace at Pacific Performance Racing, in California, has a neat kit that puts a 428 stroke crank (4") into a 3" main motor (326,350,389,400) to turn it into a serious torque monster. pontiac 350 vs SBC 350 (differences) | Team Chevelle A 4.020-pound engine is much better than a 400 engine, which is much smaller and has a much larger bore. Its robust design allowed immediate adaptability to future displacement increases. Then there are the 301 and 265 engines. Continental Engines, according to the instructions in SB03-3, can be powered by this engine. Compression checks on Lycoming engines should be performed by 1191A, according to 1191A. Its always best to Check the chambers by "CCing" them, I have seen most of the time, pontiac heads with the date codes a few days, to a few weeks apart.Not sure why, but that is the way I have seen it on many engines that have never been taken apart, so I assume it is common from the factory. This was a small block V8 produced by General Motors, and was used in Pontiac vehicles from 1967 to 1981. The process is risky in and of itself. While it's not practical or necessary for every performance level, hot honing may benefit those chasing every last horsepower when racing at the most competitive levels. It used to be possible to find good factory forged rods for the $uper Duty at the factory, but now there are cheap aftermarket forged rods everywhere. If a head is from a 455, the chambers are too large. If the cylinders cylinders are still in good shape, you might be able to hone them, ring them, and not have to worry about them for years. It was interesting to see how well it turned out because it was built to fill a gap left by Pontiac by replacing the 215ci engine it had used in the up until 1963. In M84-15, their previous instructions were revised. CID: Cubic inch displacement of engine. The A.P was most concerned about the cylinders leaking, because he could hear air coming from the exhaust as he approached. Pontiac 350 engine | Hot Rod Forum Pontiac heads are popular among Pontiac enthusiasts because of their ability to produce high horsepower, a characteristic that has made them a favorite among performance enthusiasts for decades. It was also known for its ability to be modified for increased performance. Pontiac heads also offer a great value for the money, making them a great upgrade for any Pontiac engine. In addition, the 2009 G8 GXP is powered by a Corvette engine. Stock Pontiac iron cranks can handle anything you throw at them if properly prepped. Though 400 and 455 blocks are most popular for modern performance builds, the 455 was far more desirable for many years for its larger displacement, and cost reflected it. Bottom End. The 350 Poncho is a damn fine little motor. Big-Block vs. Small-Block V-8: What's the Difference? - MotorTrend It replicates the load a block sees when a cylinder head is installed. All 350s can safely be bored 0.060-over. Going any bigger will require a larger aftermarket block. The Pontiac 400 is a mid-size V8 engine produced by Pontiac from 1967 to 1979. For those who fit into either category, Ken "Ace" Brewer from Pacific Performance Racing (PPR) has an answer. But how much boost can a stock 350 Pontiac take? The volume specifications of the chamber should be considered. If youre looking for a car with the most horsepower available in a Pontiac, the 2006 Grand Prix is the vehicle to buy. There is no need for high-volume oil pumps. Here is a sample from Chapter 2 to get you started. The smaller journals reduce bearing speed and improve block integrity, giving racers the performance and reliability required for high-speed operation. The cast crank has plenty of strength, so it can withstand being battered for years. Impressive numbers like these made our dyno day go by pretty fast. This engine, also known as the Small Block, was first released in 1967 and was used in a variety of Pontiac vehicles until the mid-1990s. Still going to be a major obstacle to get any compression in a little 350 with 87cc chamber.you need heads down around 72cc just to get somewhere near 9.2:1 compression wtih a flat top piston. In the first version, the bore was 3.75 and the stroke was 3.78, both of which were actually 3.525 and 337ci. There are many powerful Pontiac engines, but Tommy Youmans Twin-Turbo Judge stands out as the most powerful. High CR will not be supported by low octane fuels. Thanks Last edited: Jun 18, 2008 Jun 18, 2008 #2 9 9firebird5 Veteran Member Dec 4, 2007 160 The G8 GXP exemplifies Pontiacs commitment to power and performance. But now I have learned that many prefer the Quadrajets. Check for valve-to-bore contact by placing the valves, retained by clothespins, in the heads. You might want to consider getting your hot side built if you have a set of them. Start by selecting a good 010 casting. The thin cylinder walls in a cylinder wall are likely to be found when it is pushed to090 degrees. It is recommended that all 350s be bored to a safe temperature of 0. Murilee Martin / May 29, 2023 Eclipsed by the larger 389, 400, 421, 428, and 455 engines, the 350 is the Rodney Dangerfield of Pontiac motors. If necessary, I would then save some money or, if possible, upgrade gradually. Though external dimensions remained very close to the original 287 design, the V-8 eventually displaced as much as 455 ci by increasing bore diameter and stroke length. The blocks of all of these engines have remained the same size and weight, making it difficult to distinguish the 11 different engine displacements. Some of these parts will fit on all of these blocks, but they may or may not work. Doing so will allow for a better understanding of the engines capabilities and will assist in making informed decisions about how to rebuild it for optimal performance. What does the emission test in germany consist of? The main bearing caps are fastened to the block by two large bolts in most instances and located by dowel pins to prevent the caps from wandering during high-speed operation. When it comes to understanding the performance capabilities of a classic Pontiac 350 engine, one of the most important factors to consider is the compression ratio. Unlocking The Potential Of The Pontiac 350: How Much Boost Can It Take The combination of modern engineering and classic muscle car appeal is the perfect match for drivers seeking a classic vehicle with a modern twist. The engines feature a cast-iron block and head and two valves per cylinder. 326 CU. Stock Bore. It usually takes one to two days for the engine and major component casting dates to appear. I could get an old Pontiac # 13 cylinder head with 72cc, 2.11 / 1.77 or a head with 1.96 / 1.66. This engine uses Dana-Perfect Circle rod (CP-758P-20) and -groove main bearings (MS-483G-20), which are available in common oversizes. It should be driven regularly in the city in summer. Said to enhance sealing by 6 percent, this engine uses the latest Total Seal gapless top rings, conventional cast-iron second rings, and a thin but standard-tension oil ring assembly. I would like to have more power cheaply without the suitability for everyday use suffers. With the MP T70s w/.68 a/r turbine housings, there would be no room in the turbine housings for water. SB03-3 contains all of the information you will need to perform the compression check and interpret the results. The most common method of boring 350s is to use 0.060-over oil. With a bore of 0.060-over, all 350s can be bored safely. The 230-cubic-inch engine came in mid-1960s passenger cars like the Chevy II, Camaro, Chevelle, and some full-size cars as well. Their Semco 409CI Pontiac, which demonstrated their ability to produce engines that will exceed even the most demanding drivers expectations in the Jeg Engine Masters Challenge, is yet another example of their capabilities. It is one of the most powerful vehicles ever made with a 6.0-liter LS2 V8 engine that can produce 400 horsepower and 400 pound-feet of torque. Compared to many other V8s, the 400 is considered to be a good balance between power and efficiency, making it a popular choice for many car enthusiasts. However, it appears that the OP will probably refuse to try that option. The main journals of a 389 or 400 block Pontiac head are smaller, which means more main webbing material, resulting in a stronger overall structure. The small-block beast delivered an incredible power curve that looked more like what a fat Rat would produce. The date for joining was September 1999. My nac piston on my 455 was going to get nearly 9:1. As a general rule, it is safe to use up to060 blocks. With pump gas, the 409 CI Pontiac engine was able to generate an impressive 561 horsepower. Whether you need a mild street engine or a powerful race engine, DCI Motorsports has the experience and expertise to help you achieve your dream for your Pontiac engine. With careful planning and expert knowledge, it is possible to bore out the Pontiac 350 to an even greater degree than the Chevy 350. The Pontiac 350 is a reliable and powerful motor that can still be found in many cars today. How much over standard bore 3.250 can you bore safely without getting into the coolant territory? It's beneficial when running a camshaft with very aggressive specifications. This powerful engine produced an incredible 561 horsepower at pump gas, which is nearly as powerful as that produced by the majority of engine builders. Be sure the block you select has the correct mounting points for your chassis. A V8 in a Pontiac is the same size as one in a Chevrolet. Some argue that because there are only ten bolts per side for a Pontiac head, it may have sealing issues if it is used in a high-powered environment. This can increase the engines displacement from 400 ci (6,554 cc) to as much as 416 ci (6,784 cc). Some earlier blocks may be of similar or better quality (particularly the '60s Super-Duty castings) but such examples are rare and may present compatibility concerns with today's parts. This may make it difficult to determine the displacement of your Pontiac V-8. If you're considering a stock Pontiac block for your build, identify the casting you're starting with. It will take several years for the cast crank to produce enough power to match its strength. Blocks with four bores can still be found everywhere. In 1968, the 350-cid HO V-8 engine in the 1968 Pontiac Firebird reached 320 horsepower, 35 more than its predecessor, the 326-cid HO V-8 engine. However, its important to note that it can also be easily bored out to increase the engines displacement and power output. Facts and Information About the Chevy Inline Six Engine - OnAllCylinders Ford 9 4:11s: Thats a pretty good sounding engine. 305 Engine Build Questions & Much More - Car Craft Magazine - MotorTrend It's drawn in, pressurized, and dispersed by a positive-displacement rotary pump that's driven by the camshaft. You can find a variety of online calculators that can assist you in calculating compression ratio. Pontiac used the Quadrajet on engines ranging from 301 to 455 ci. Another common modification performed to the lifter bores in a stock Pontiac block is to tap the lubrication holes and insert small restrictors whenever a solid-lifter cam is used. This years JeGS Engine Masters Challenge saw DCI Motorsports take part, with their Semco 409CI demonstrating why they are a household name. Blocks made between 1968 and early 1970 were the most desirable to look for. Lifter-bore brace kits, such as the Mega Brace from SD Performance contain formed plates that are bolted, epoxied, and/or welded into the lifter valley to improve lifter bore strength. It is advantageous to modify the heads of your Pontiac to improve engine performance and fuel economy. Description of specs and parts included in Street & Strip 400 Pontiac rotating assembly kits. After installing the rear of the 4th Gen at the request of Pontiac High Performance, the rear was repainted and eventually sold for nearly $1,700. It is important to note that when boring a Pontiac 400, you must use a torque plate to ensure the cylinder walls are properly supported. If youve recently installed new valves or modified the combustion chamber, youll need to measure them first. If it didn't, we wouldn't waste time telling you about it. It was a watershed moment in history because it was the first time a street engine capable of such power had been built. Its not a problem to make 350 horsepower from a 400 Pontiac engine. The major drawback is the small 3.875-inch standard bore, which restricts ultimate breathing potential and creates valve-to-bore interference with big valves and high-lift cams. The V-8 was a truly revolutionary engine that set the standard for performance and gave rise to a new era of power in the automotive industry. If the block had an overbore of 90 degrees, the holes would overlap by about a half inch, except at the end, which would be out in the open.