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GMC Carburetor

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0% found this document useful (0 votes)
275 views32 pages

GMC Carburetor

Uploaded by

Mat Jones
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© © All Rights Reserved
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Ralph; Enclosed are the DELCO carb parts Uist for the GMC motorhome. The seven carbs used on the GMC are covered in the three bulletins, #9C-4000, #9C-4001 and #9C-4002. Two of these. sulletins, #9C-4000 and #9C-4001 show by their issue date that they were up-dated versions, and I'm sure there has been up-dates since then, especially in some of the parts numbers, ab improvements were made, and as some ob the various parts were consolidated to be used on several cars numbers. This is a common practice used by parts suppliers, and results in the ever-changing format of cunrent pants lists, Also included are the sheets on Brad Urban's Carb Shop. I have hi-lited the items that pettain to a proper carb for the GMC, the boring of the primary throttle body and installing larger throttle plates should remain strictly up to the individuat owner, as I feet it is not for ever application. These sheets were furnished to me from Bob Miller, who has helped Wally Arntzen convert from E.F.I. to a cank built ty up by Brad Unban, Wally Aintzen bought Fritz Slama’s burnt coach, and it had the 500 CAD engine with uel injection, which was causing Wally a lot of problems. They sent 4or a carb designed for use on the motorhome, and after numerous phone calls between Bob and myselt, they have it up and running, and seem to quite satisbied with the change-over pergounance. Just a Wriek histor on the Rochester Quadrajet Carburetor: It was introduced in 1965, a revolutionary design for that time, and went thu subtle changes up to 1975, when stricter emission standards were introduced. These emission standards forced changes in idle, obf-idle and main system metering control, ad noted in the. canks and their components for the’ 75 to’ 78 GMC's, especially the '77 and'76's. Though this does not pertain to the motorhomes, but in 1981, the Q-JET carbs were equipped with electronic. metering conthols, to meet the stringent emission and economy regulations, and this continued until 1986. This is good prook of the solid basic design and the versitility engineered into the Q-JET. I hope this will be some. info you can use, it is always good to have ample reference material, especially on some of the specialized items. When one looks at the cost per mile ob driving the coach, and of that cost per mite, hued is the biggest percentage, 10 a good, solid working fuel system is quite an asset. Ba Dew GMC MOTORHOME CARBURETORS The GMC motorhomes came factory equipped with the Rochester Quadrajet carburetor. Seven different carb numbers were used, depending on the year and if it had Federal or California emission standards. The 1973 and 1974 years had carb # 7043254, while the 1975, 1976 and early 1977 with the 455 engine had carb # 7045254 for Federal emissions, the California carb for those years is # 7045554. The 1977 coaches with the 403 engines has carb # 17057254 for Federal use and the California carb is # 17057559. The 1978 coaches have carb # 17058254 for Federal application, and the California carb is # 17058559. These carb numbers can be found on the left side of the carb, stamped on the flat surface close to the secondary throttle shaft. The numbers will read from the bottom up. There will also be a four digit number in that same area, which is the date of manufacture. The 1973 to 1976 coaches have carb numbers that start with "70", while the 1977 and 1978 carb numbers start with "170". The carbs with numbers starting with a "170" were built for the stricter emission standards, and some parts for these carbs are quite different from the "70" series. DO NOT INTERCHANGE parts between these different series carbs. One example is the "170" series has primary metering rods that are 0.080" shorter, they have a different taper to the rods, and these carbs used different sizes of primary jets. Genuine Rochester parts are marketed only thru GM or DELCO parts dealers, and are made to the proper spec's to bring the carb up to it's correct settings. Repair Kits are available thru DELCO that include all gaskets, needle valve and seat, etc. Other parts that should be included in an overhaul are the float, which has an updated part number, (7046301), the power piston spring #7036019, and the correct primary metering jets. A proper carb overhaul should start with the carb dismantled and soaked in carb cleaner to remove all the dirt and the varnish that has accumulated over the years of use. The varnish residue comes from fuel evaporating during periods of non-use. -2- Warpage of the fuel bowl and air horn assembly should be checked. Numerous fuel bowl assemblies have been noted to be severly warped, this is a problem caused by over-torquing the 5/16" front mounting bolts. These bolts should be torqued to 10 ft/lbs only to prevent carb damage. A common complaint of GMC coaches is hard starting, especially after the engine has been shut off for several hours or overnite. This is caused by the fuel leaking out of the fuel bowl thru the four soft plugs in the bottom of the fuel bowl assy. This problem can be remedied before the carb is re-assembled by coating the bottom of the four plugs with a high-temp, two part epoxy. A good choice for this epoxy is DURO Master Mend metal repair #QM-80. It is a high-temp epoxy that sets in 4 to 6 minutes, and is a product of Loctite The Rochester carbs used on the GMC have some internal parts that were designed and built just for use on the motorhome. Keep in mind most loaded coaches will weigh at least three times of what a full sized car does, so power demands are quite different The primary metering rods are an example of this, they were designed with a special power tip, and in the "70" series carbs these rods will be stamped with "D-50". The "170" series carbs have metering rods of a different design and should NOT be used in "70" series carbs. All Q-JET carbs have primary metering jets that were designed only for the Q-JET carb. Other jets may screw into the jet ports but may have a different height, thus not matching the metering rod, therefore giving an improper fuel flow thru the jet. All GMC carbs have the same secondary metering rods, and will be stamped with a "CJ" on them. These are quite durable rods and usually give no problems. The secondary jets are factory installed and not easily removed, but are also quite durable and give satisfactory service. With the proper metering rods and jets, the correct power piston spring and a good, true intake manifold vacuum, the carb will dispense an Air-Fuel ratio of approximately 14 to 1. This will be with manifold vacuum of 8" or more When power is required and the carb is operating on both the primary and secondary bores, the Air-Fuel mixture furnished to the engine will be in the range of 12 to 1 .This power ratio is a richer mixture, used to develop the power needed, and a richer mixture also helps to cool the internal engine parts, such as the pistons, valves and heads for longer engine life During a typical drive with the motorhome, whenever the intake manifold vacuum is at 8" or above, the carb will be in the so-called cruise mode. It is operating on the primary part or the front two bores of the carb. With the proper power piston spring, #7036019, which has an operating range from 4" to 8" of vacuum the vacuum overcomes the spring tension and the power piston is pulled down, pulling the metering rods down into the jets. This Positions the large diameter of the tapered rods in the jets thus restricting the fuel flow thru the jets and resulting in a leaner mix. As the power demand is low, this results in good economy. When more power is required and the throttle is opened more, manifold vacuum starts to drop, and as it drops lower than 8" of vacuum, the power piston spring tension is stonger than the vacuum and the spring starts pushing the power piston up, raising the metering rods with it. As the metering rods are raised, the smaller diameter of the rod is positioned in the jet, and a larger volume of fuel can flow, causing a richer mix to supply the added power called for. When vacuum has been reduced to 4", the spring has completely overcome vacuum and the power piston and metering rods are in the fully raised position. At this stage the primary bores are furnishing close to their maximum volume of fuel, and the A/F ratio will be approx 13 to 1. As the trottle is opened even further, calling for more Power, the back half or secondary part of the carb goes into operation. When the vacuum drops below 4", a vacuum break diaphragm on the side of the carb allows the air valves on the secondary bores to open up. As the air valves open up, they operate a cam that lifts the secondary metering rods. As the secondary rods are lifted off their seats, fuel begins to flow thru the secondary jets, furnishing the added fuel needed to satisfy power requirements. If the power demand is strong enough, the carb will eventually be at W.0.T.(wide open throttle), and the A/F ratio should be in the 12 to 1 range When power requirements start to diminish, the throttle begins to close and manifold vacuum begins to increase. As it increases past the 4" mark, the same vacuum break cylinder that allowed the secondary air valves to open, now begins to close the air valves. As the vacuum increases, the secondary air valves become fully closed, the secondary rods are seated and fuel is stopped flowing in the secondary jets. The carb is now back to operating on the front or primary bores again, and as vacuum goes up and past the 8" mark, the carb will be back in the cruise mode for economy So from the above, it is easy to see how important good manifold vacuum is to carb operation and engine efficiency Manifold VACUUM is the SIGNAL the engine gives the CARB, so the carb can adjust to the immediate fuel demands of the engine. This is why vacuum hose replacement should be part of any carb re- build. Vacuum hoses are subject to engine compartment heat and fuel fumes and can become cracked and brittle, allowing vacuum leaks, allowing unfiltered air to enter the engine and to give false vacuum readings. Don't forget the short hose on the transmission modulator, located on the lower right side of the transmission. Use a top quality hose with heavy enough wall thickness so it won't collapse during high vacuum conditions. A good choice for this is the Belden brand sold through NAPA stores. It is a good policy at this time to replace the PVC valve, located on the right rocker arm cover. The proper replacement for this is Delco # 679, as this valve has the correct tension spring and valve for both Olds engines. The PVC hose can be replaced with a heavy wall 3/8" fuel line hose, with a small hose clamp on each end. I hope this helps to understand the Q-JET carb A proper carb overhaul can result in as much as 1 mile per gallon increase or more in mileage, so for the GMC that is about a 10% improvement, plus you have the added performance. This is a good return for the few dollars invested in the carb repair. An increasing problem for Q-JET owners is finding a repair shop that has the skill and knowledge to do a top-notch repair job on the Q-JET carb. Most present day fuel system technicians have been trained for the fuel injection systems that are on the late model engines. The removal and dis-assembling of the Q-JET is not a overly difficult job, as long as it is done slowly so as to familiarize one-self with some of the components, and their respected positions. There have been several good books written on these carbs, one of them being ROCHESTER CARBURETORS written by Doug Roe and published by HP Books, #014. The DELCO carb repair kit has all the necessary instructions for re-assembly, and list the complete spec's for proper adjustment. GOOD LUCK AND HAPPY GMC-ing Yop LDeawae Feb 1, 1994 Ralph; I read with interest the chart you sent on the GMC engine numbers and the carburetor numbers for the various year coaches. It is important to note that there are numerous errors and deletions for the carb parts in the 78Z motorhome parts book. Just some of the examples of this; on page 12-12 of the parts book, there are only THREE primary metering rods listed, (key # 24), where if you check the DELCO parts list that I sent you, there will be FOUR metering rods, used on the seven carbs for the various years. As for the primary jets, (key # 25), the parts book only list THREE jet numbers, when actually there are FIVE jet sizes used, depending on the engine application. This has caused a lot of confusion, especially when the part numbers used by GM and the DELCO part numbers differ for the same part. This is more-so aggrevated lately by the fact Delco now has up-dated their parts list, and are using the last FIVE DIGITS of the GM number for a DELCO number. An example of this is the DELCO POWER KIT, say for the 1973 to 1976 coaches, is changed from the original DELCO number of 9258 and 9269 and combined into one kit with a DELCO number of 76057. The GM number for this kit will be 17076057, note that it carries the same last "five digits",only is preceded with "170". These changes were to consolidate parts and keep better inventory control. So, it is easy to see how valuable a good parts man is when it comes to keeping up with changes, and be willing to dig up this info! As stated above, the 1973 to 1976 coaches, and the early 1977's with the 455 engine have a POWER KIT number of DELCO 76057, and the late 1977 thru the 1978's with the 403 engine will have a DELCO POWER KIT with a 76031 number. The overhaul kit is no longer available from DELCO,that kit had all gaskets plus the primary metering rods, the primary jets, needle and seat,etc for that particuler carb. The kit available now is the "POWER KIT", which has all gaskets, needle and seat and other small parts for a proper re-build. A VERY IMPORTANT step in assembly of a carb is to have the correct gaskets for that specific carb, as there are changes in air passages in the body casting of some carbs, and without the proper gasket, these passages may be blocked off, if the gasket does not have a punched hole to allow these passages to operate. EXAMPLE; From the DELCO PARTS LIST ITEM #2,the AIR HORN GASKET for the 1977 coach is #17051797, while the gasket for the 1978 carbs is #17056357. Both of these gaskets will be in the DELCO POWER KIT #76031, as this kit covers all the carbs for the '77 and'78 coaches with the 403 engine. While we are on the subject of gaskets, the heavy gasket that is used to mount the carb to the intake manifold, and also the gasket between the throttle body assy and the fuel bowl are of a design to not only be a vacuum tight seal, but also to be an INSULATING barrier to prevent intake manifold heat from transferring to the carb and causing fuel perculation in the fuel bowl. To comment on the use of different carbs for GMC motorhones, be it from a Toronado, Eldorado ect. or having a carb number not listed in the DELCO carb numbers for the motorhome: EVERY ROCHESTER Q-JET CARB HAS A NUMBER STAMPED ON THE CARB. This is NOT a PART NUMBER, it is a CARB NUMBER that idenifies what the carb was designed and built for. It may be built for a passenger car, it may be used in a delivery van, or , in our case, it was designed and built for use in the GMC motorhome. The AIR HORN ASSY, FLOAT BOWL ASSY, and THROTTLE BODY ASSY may be of a common basic design, but the INTERNAL PARTS and COMPONENTS will be installed to make this carb do the job it was intended for. when the engineering for the carb on the GMC was done, Rochester took into account what was required, such as weight of the vehicle wind resistance, payload carried, economy, and proper Air-Fuel mixture to insure longivity of engine components, and starting in 1975, to meet emission standards. This research resulted in the installation of the various internal carb parts specified to provide the performance required of the vehicle it is going to be installed on. These parts usually consisted of various sized primary jets, sized primary metering rods, the correct power piston spring, and secondary metering rods. There may be some subutle changes in air bleed orfices or fuel pick-up tubes,ect, but the above items do the main job of meeting the spec's called for. An example of spec-ing out a carb is the ones used in the GMC, for instance, the '73 to early '77 have a primary metering rod that was designed JUST for the GMC, and is stamped with "50-D". This rod is a special designed rod that has a “power tip" that meets the needs of the motorhome, and is used in conjunction with the #7031970 metering jet and the #7036019 power piston spring. This combination of parts in the primary side of the Q-JET carb gives the 455 engine the proper fuel ratio needed. The LAST TWO digits on the jet number gives the jet size this jet being a #70 (.070" orifice size), and the power spring has a range of 8" to 4" of vacuum. This carb is provided with SECONDARY METER RODS that will perform according to the requirements asked for, in this case it is rod #7045780, which will be stamped with the letters 'CJ'. These are the parts used in the Q-JET carb for '73 thru the early '77 coaches with Federal emissions. The ONLY change for Calif. emissions carbs in regard to the above internal parts, is the PRIMARY METERING JETS, which are #7031968, a jet .002" smaller in size.This jet size difference and a few minor changes in the throttle body assy was all that was needed to pass Calif. standards. This is a very modest part change, but in order to IDENIFY the difference between the two carbs, ROCHESTER stamped a DIFFERENT CARB NUMBER on the CALIF. carb, (#7045554) to distinquish it from the FEDERAL carb, which has (#7045254) stamped on it. This is why the GMC has SEVEN CARB NUMBERS in it's five years of production, improvements and changes brought on mostly by the emissions compliance, but every change in a carb requiring a NEW CARB NUMBER -4- TORONADO CARBURETOR NUMBERS 455 ENGINES 1972 7042251 7042252 1973 7043252 1974 Fep 7043252 CALIF. 7044557 1975 rep 7045185 CALIF. 7045485 1976 FED 17056252 CALIF. 17056552 403 ENGINES 1977 FED 17057257 LATE '77's 17057259 CALIF. 17057552 LATE '77's 17057555 1978 FED 17058257 17058259 CALIF. 17058555 I am enclosing the spec sheets that come with the DELCO POWER KIT, spec sheet #153 from the KIT #76057 which covers the carbs on the '73 to early '77 with the 455 engine, and the spec sheet #158 from the KIT #76031 which covers the carbs on all the 403 engines, '77 thru '78. Sheet #153 has almost 190 carb numbers listed with sheet # 158 just a few less, so it is easy to see just how many different carbs ROCHESTER built for a specific job to do, each carb with a different number and different parts and various settings to accomplish it's assigned job. This is not to say that some carb bodies cannot be used on the GMC, there are some expert carb shops that can measure and test various carbs and bring them up to a level for good motorhome performance. The use of improper repair kits and poor workmanship are the causes of the majority of unsatisfactory carb repair jobs. A worse situation is an owner exchanging the original carb for a rebuilt carb and not getting the proper spec's for the motorhome. 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Erg zeiek | SNiiias sxoHo | ~suaaVvoTNA ‘ONLLaS trois ci awons £861 Arenuer Z Jo z eBed gL wos WH Seo ae aie THzce0cr vn S20 ave para zocceoct Teper S20 eee ‘ee0990c1 ci S20 aie eSS00C1 YN 30 aie zes88001 pu ‘60 aie 65r8021 ap 060" az S6sve00t YW seo az ‘cecre0ct WN S20 ste ezve0Lt ro zeceooLr of. aezes0ct ww m, eezROLL WN of Ww eee we ww Ww ww wy WN YN wy ‘ezo80ut wy oszoeut YN ‘eszogout YN eaz090u1 YN zaz09010 WN oS sz0g0.1 WN oi ww ose oe WN ot oF 29% ww ott ote oie WN oft ote, 2 WN fr ro 002. ww ose ove, 90 ww oe ove, 08, Nz. ott Pa ote, Ne St oe ore | Ne ost, ee of az | ost eee, ate {een eye a 8 off 095802 CARB KIT Ie | g INSTRUCTION SHEET FOR ROCHESTER QUADRAJET CARBURETORS-4MC,4MV Rochester Products Carb Kit contains all necessary parts and instructions to tune-up your Rochester Carburetor properly. When similar parts are contained in the Carb Kit, choose the ones that most closely match the existing parts. Some parts in the kit may not be needed. 1, DISASSEMBLE carburetor, Use accompanying exploded view as a guide. ‘= Remove pump lever by driving roll pin through far enough to permit release of lever: + Remove air horn screws. See tightening sequence for locations. * Power piston and retainer removal: (A) Plastic Retainer, press down and release with a snap, or (B) Spring Clip, push up on clip to release, or if Ne Visible Retainer, use needle nose pliers to pull up on metering rod hanger. + Turn idle mixture needles clockwise and record number of turns needed to lightly bottom them, for use during reassembly. Remove needles. 2, CLEAN carburetor by soaking in an approved cold immersion type cleaner, such as Delco X55 Metallic Parts Cleaner. Solenoids, choke cover, float, float bowl inserts, vacuum breaks, seals or other parts containing rubber, should not be placed in carburetor cleaner. All passages should be blown ‘out with compressed air. 3. REASSEMBLE carburetor and ADJUST following sequence illustrated. Refer to model number for specifications. : TODEL NO. =, MODELNO, 1 MODEL M4MC QUADRAJET 1978 GMC MOTOR HOME 403 CUBIC INCH OLDS ENGINE. PARTS SHOWN ARE FOR IDENTIFICATION ONLY. CONSULT PARTS LIST FOR CORRECT PART NAME AND NUMBER [FLOAT BOWL PARTS Le ae esa cae FEDERAL CALIFORNIA, ‘APPLICATION 17056254 17058569 ‘CARBURETOR No. 24-409 24-410 REPLACEMENT PACKAGE No. 77055636 17065067 OVERHAUL KIT 9341 POWER CARBURETOR KIT 40-466 GASKET SET ee: ‘AIR HORN PARTS — 7 17056632 1706503 ‘ir Hen Assen 2 17086367 | 3 —roasi69 ing 4 9428787 ump & Lockout Lever Hinge — — 7929912} — raw=Aic Horn == =e 7014699. rew=Air Horn $— |} te 80 eat Maing Radon 3 i onary — TOSAE22 Soe Mtring Red Ho RT = 0 7 = Lever=Air Valve Lockout = 7OR63aa = Air Valve Spring & Ca = = =F airvalve Stop CO, WO, 131, 132:M, 9X, 9FD PRINTED IN USA. © 1977 GENERAL MOTORS CORP. BULLETIN: 9¢-4002 PAGE: 2 17058254 17058559 CARBURETOR No. Tis, No. a ORETERTS i OSES ‘Stat Cover, Col & Gasket Assy. 42 417050961 ‘Gasket—Stat Cover ~ 13 7084435, ‘Vacuum Break Control & Bracket Aaiy- 14 = = ‘Vacuum Break Control Assy. 15 Toa Rod: Vacuumn 16. 17050732 r= Control ARCHING 17 17056631 17056632 Cam=Fart dle 7026339 Hose=Vaeuum 7038289, TE thoi Sat 7048804 — 7029866: = TO3231 7oaia72 7 17056615 T0500 ‘Choke Housing Acerbh = 17050764 ‘Intermediate Choke Shaft & Lever Assy. 7037865, =] Sentmintermediate Choke Shaft yoasse7 | ‘Seal=Choke Hig, to Bow) 7043368 Tover—Stat’ = 7019709. rew=Coll Level 7038808. Screw=Choke Hea. 10 Bow! 7081542 a Lever=Choke = 7029866, ——| eee Tae = 7000814 Retainer—Stat Cover 7ON1270~ I Serew=Siat Cover — fi WL PARTS. = 17055633 Fioat Bowl Asiembiy_ 7 eT 7031074 "7002117, 7028849 30-134 zi Hit ONLY ‘Gatket—Needle Seat = 7033751 Pull Cip=Float Needle a fee aces i inge Pin Float AsamBTy 7oa8aa9 — ower Piston Aer 7036019 17058329. Power Piston 17086055 17061363 ==>} 7081489, rimary 7059861 Inlet 7924281 Gener Fite Nut = Grist r=Fuel Tet TOS2TSE a ea Fuel Filter = Tle Compensator Assembly = Gasket ele Compensator —Cover—Tole Compensator — — “Serew=Cover Attachi [Spring=le Stop Sere 7o02T21 Serew=Tale Stop a 7041471 Tsert=Float Bow 7031365, —Batte= Float Bow” 7042978 —Spring=Pimp Fetura 17083072 —Pomp Assembly 7026138 Rod=Pump 17051796 — Tnsert—Anerora Cavity a 7041473. Lever=Secondary Lockout _ ‘THROTTLE BODY PARTS _ on Tl 77058648 17058964) “Throttle Body Assembl 62 KIT ONLY Gasket—Throtile Bod) — 7 3 7035790 Screw--Throtle Body — 4 7048532 le Needle — 7 65 Doe ‘Spring—Iale Needle 66 7041487, ‘Lever—Cam Follower 67 17051434 ‘Spring=Cars Lever = 8 7041488 Fast ile Lever 8 7036078 ~Screw-—Fast Idle Laver Serew=Fast idle Adjusting ‘Screw 410087, “euNWey eujGua aunjewiaid asneo Aiqissod ueo Kou) pue Woy) Uo Sioyeinqeo Boum ay) Lim poyeredo Buleg Aigeqoid ave pue sie@K oy) Jono peBUEYD usag eey siojeinqued sewo\iojou O”NO AuEYY “squinu Yed mau B y YEN AREY LOU DINOM WWD sMIOUIO ‘wed JOM) AN YIM axgEaBUELOLOIL IgISSod pue asojo Aven aqKew! 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S161 ZLPOOLAS “ON 1eUBS JeUY (S261) ‘98815021 szsror Psscror rele U61-.S/6L ZLPOOLAS ‘ON 1eUAg 01 1OUd (S261) zLe9%0L SzeroL vsecroe zesaly -SL61- PBL z189P0L vszevor Psecror o1gery e161 ‘SeuBUS Soy — yoog sued Zed 00g sued 782 00g sued ZeL Se10N ON INEUIEA “ON INEYIEAG IED “ON JoVeINqIeD “oN UOVeINGIeD ON oU|bUS see, cooled ov Wo Jeys0ys0u wo Wo rd. SuddWAN Luvd YOLAANGUVS 72 JNIONA ANOHYOLOW IWD anjea ajyzosya Asepuosag Buuarey W3LSAS AYVONOD3S sayeyd 8014130 2qny ig 119m 401813309 p3aiq ure yam ulew Asepuoces winnoe, :* wnnsea piojruew pos Buayaw yew Asewiig tht KL CARBURETOR SHOP PRICE LIST [ROCHESTER CARBURETOR: easaesctonmamms Remanufactured Quadrajets Early 65-76 Late 77-Up Non Computerized Stage 2 Stage 3 Stage 1 ‘Stage 1 Stage 2 Stage 2 Stage3 Stage 3 **Early style carburetors availabilty subject to core availability, Rebuild on your Rochester Carburetors sent in, Four Barrel Quadrajet Stage 1 Stage 2 Stage 3 Stage 1 Stage 2 Two Barrel Dueljet Stage 1 Stage 2 Stage 1 Stage 2 Two Barrel 2G Stage 1 Stage 1 Stage 2 (ROCHESTER TH ANDI Rebuild and modifications on your unit sent in. TPI . Stage 1 ‘Bored with larger throte blades. TBI Stage 1 Bored with larger throwle blades .. = Stage2 Complete rebuild, throtde shaft bushings and stage 1 work ace Stage 3 Clean injectors, check spray patter, pressure leakdown tes, and siage 1 & 2 work [BASE PLATE THROTTLE SHAFT BUSHINGS ‘All Quadrajets, primary side All Dueljets 3 F ‘Square bore Rochester TPI .. Rochester TBI |. scsco _ If secondary side needs bushings also add... [ROCHESTER QUADRAJET BIG BORE Bore primary throttle bore and install larger thoue blade. XLALL PRICES SUBIECT TO CHANGE WITHOUT NOTICE X SEE OTHER SIDE BRAD URBAN'S CARBURETOR SHOP ORDER BLANK 1457 E. Philadelphia #24 + Ontario, CA 91761 (909) 947-7744 + (909) 947-9722 Name Phone Address Cy State Zip ‘VEHICLE INFORMATION Year Make Model. Engine Size___.....___ Transmission Q Automatic Q Standard O 2 Wheel Drive O 4 Wheel Drive Q Cruise Control LENGINE SPECIFICATIONS Intake Manifold ‘Type Of Heads Stock Heads: O Yes QNo Modifications To Heads Headers: QYes ONo = QDualExhaust Single Exhaust Type Of Mufflers Air Filter DOpen Stock (CAM: Advertised Duration se tee teeta teste Ate 60 eee ify Gears ‘Compression ‘Maximum RPM How Driven: Q Steet O Stip O Street&Strip 0 Towing Altitude Where Driven FOR CARBURETORS BEING SHIPPED TO YOU, PLEASE CALL FOR SHIPPING COSTS SMALL PARTS Part ID# Description Quantity | Unit Price (California, add sales tax at the percent rate for your county, Tax COD add $3.75

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