Note the diff in smaller carbs as it slows the car compared to the larger cfm version. 450 hp Buick 350s run great with a 850 Demon, and 550 hp na motors have been proven with a 1000 cfm carb. That said a 650 cfm will work ok in lower rpm ranges.
That said a 650 cfm will work ok in lower rpm ranges. actually, for a less than 'full race' build, the 650 should be much more responsive.
The small primaries on the Q jet provide good velocity and therefore great throttle response compared to a holly style square bore carb with four equal sized bores.
I didn't know that Kenne-Bell had there own manifold. KB44200?. It looks like they did a cam change along with the manifold change, and not a huge improvement over the stock one (Test #12).
the kenne bell manifold should have been a ta performance manifold,they where a dealer for ta back in the day
Great info. From both attachments, it definately looks like the 350 benefitted greatly from a simple gearing change, but not as much as I would've thought when the headers were slapped on. I wonder how different the times would be on a stock 350 Skylark of early 70's vintage, with 4-bbl. an dual exhaust, if the 350/3.64 (or 3.42) tranny and gears were swapped out for a 700R4 / 4L60 and 3.42's. ...hmmm.... Bob
Hey Bob the Tomatoe, I think your answer is in test# 40. By going to the 4 spd(in this case manual) they picked up 3.1mph and .5 seconds. It would seem that a 700R4 with a 3.73 rearend would be very nice for a street application.
71CustomConv, :gp: That has me wondering if the auto's ability to shift without letting off the gas is enough to overcome its less positive connection with the tires, compared to the manual (plus, the 700R4 has better gearing). I think I would go with the slightly taller 3.42's, too Even stock small Buick V8 has oodles of torque coming off the line. This means you can use less gear and still get a decent launch. Too much gear and all that power goes up in smoke....literally! :3gears: :beer Bob
Does anyone know if you can put a different first gear in a 700R4? The 3.06/1 is a little high like you said. The final ratio on a 3.64 rear would give you the cruise rpm of the 2.56 to 1 from a Custom with AC. My car just purrrrrrrrrrrred at 70mph on the highway with the 2.56, but was a dog off the line. In the notes above the say big valve heads. Are they just referring to the 73 and new heads with the bigger valves or did they actually go even further?
I am not a fan of the 700R-4 myself and you would need the adapter plate to convert to the BOP boltpattern. If you have driven a vehicle with a 700R4 you will notice that the spread between 1st and second gear seems too large. I suggest, 3.73 gears with a 200 r4. Would give you great acceleration and a peferct highway cruise rpm, and a very easy swap if you had a th-350 or ST-300 trans which most smallblock cars have. More info here: http://www.v8buick.com/showthread.php?t=109774&highlight=overdrive+swap And using a calculator you can experiment with the gear ratios: http://www.f-body.org/gears/ Using the above calculator you can see that with a 27" tire, a 3:73 gear would really get you into the sweet spot for all driving conditions when using an overdrive. First graph is using a 5000 rpm shift point and the second is a sunday cruise with decent fuel economy. notice how the rpms never get too low after the sifts are made, which made the engine happy and ready to pull from any speed. *keep in mind there will be 5-8% converter slippage unless the converter is electrically locked so these rpms are not EXACT.
Todays lock up converters would widdle away at that advantage the manual trans had over the auto forsure. And I completely agree with you opinion on gear choice!
Sean, Personally, I'd drop the lock-up TC. IIRC, it requires a computer to activate it (maybe that's only with the "E" tranny's), it's an easy swap and its 37 lbs. you won't have to drag around. 3.73's + 200-4R, in 4th gear = 3.73 x .67 = 2.4991:1, effective. If a 27" tall tire is used then the formula is 3.73 x .67 x 60mph x 336 / 27, which all equals roughly 1866 RPM. Not a half bad crusinig speed. I wouldn't want to go much slower with the engine though (i.e., oil pressure). The thing is, I wouldn't want to put too much engine in front of that tranny. Remember, the TH200 (the 200-4R is basically the same with an OD gear added, internally) was originally designed as a 3-spd auto for The VEGA (remember those? ), so even though, by design, its part of that great family of Turbo-Hydramatic trannys, its actually built for a fairly low power application. Yes, Buick used it in the GN's, but those were "beefed" versions of that tranny, not to mention that engine power enhanced via turbocharging places different stresses on the driveline, compared to more traditional forms of engine power enhancement. Don't think you can pull any ol' 200-4R out of junkyard, rebuild it and bolt it behind your 300-400 V8 and expect it live indefinately. If your SBB is stock or close to it, then you'll probably be ok, but once you start hot rodding the engine, its time to move up to something bigger that'll handle a larger load, better. ...oh, and the 700-R4 has been around since about 1977. You should be able to find one with a BOP bellhousing pattern. It might not be the easiest thing in the world, but they should be out there. ------------------------------------------- 71CustomConv, As for the 700R4 having a "tall" first gear. It's actually the lowest I've ever heard of in a passenger car tranny. TH350 is 2.52, TH400 / 4L80 is 2.48 and TH200 / TH200-4R is 2.74. 1rst gear in TH700-R4 + 3.42 rear gears is litterally the same (slightly shorter, actually) as 1rst gear in TH350 + 4.10's....and you end up with a much nicer cruising speed with the 700-R4. 2nd ends up being about a 1/2 point taller with the R4 +3.42's, compared to 350 + 4.10's, of course by that time you're already moving so the taller overall gear ratio can actually work to your advantage, depending on how your engine is set-up. Bob
I have seen hens teath but never a BOP 700R4 and no sadness on my part... As stated earlier in this thread the 200-R4, not to be compared to the th-200 is a very good trans. and the lockup is worth a bunch. I would only use a manually locking converter on comand, but this is simple stuff. The 4L80E is a different story, it either requires a full manual setup or a computer. Having a tunable shift firmness, rpm and rpm based on load patterns is almost more important than making the power. The Th400 is the most reliable heavy duty trans and the 200R4 is the best medium duty trans, the 4L80E is almost perfect till enter the new 6 speed GM auto....
71customConv Does anyone know if you can put a different first gear in a 700R4? The 3.06/1 is a little high like you said. Bob the Tomatoe As for the 700R4 having a "tall" first gear. It's actually the lowest I've ever heard of in a passenger car tranny. Bob he didn't say "tall", he said "high". as in high numerically. it's the same as "short gearing" although i agree that it's really easy to get these terminologies messed up. their argument isn't with the short 1st gear in the 700 it's the big spread on the 1st to 2nd shift. notice what Sean says here: "If you have driven a vehicle with a 700R4 you will notice that the spread between 1st and second gear seems too large."
That is right. I would rather 1st gear be closer to the TH350s but with the O.D. With the amount of torque the Buick 350 has I think the numerically high first gear is a waste. If you have a pickup and need to get a load moving its great. I think you would break the tires loose to easily in a car. On the 200R4 - If builts correctly it will handle a well built SBB. My issue is it costs 2 to 3 times more than a 700R4 in that condition. I can go to the junk yard and get a 700R4 from a early 80's pickup and have it freshened. I have to spend a lot more to get the 200R4 to take the same amount of power.
