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#53339 - 11/10/09 11:25 AM Dyno day for a 250
tlowe #1716 tlowe #1716 12 PORT ADVERTISER Active BB Member Registered: 04/01/04 Posts: 2327 Loc: Dysart, Iowa	Here it is, not all the way done with the 292 testing and you guys (and I ) want to do the same thing to a 250. I have a few of them and fellow inliners do too. Presently all the parts are ready and at the shop to do comparison testing 5 heads, stock, stock lump, 1.84 lump, 1.94 lump, high comp 1.94 lump 8 cams (Same used on 292) 2 intakes, OFFY VS Clifford and some other things. The dyno is also setup for this type engine. To dyno the 292 took lots of effort, money and supplies. Most of that would not have to be duplicated to do a 250. I am up for the task. Need help with : cost of dyno time parts swaps 1 good shortblock Strokersix has mentioned he has a good 230 and asked if I have 250 pistons. I have 250 pistons. I will talk with him about getting a 250 lower end together. Cost to dyno the 292 was in total 1800.00 and change . 400 of that being being supplies at the shop, like making and hooking up the exhaust, mounting engine ect. So true dyno time was around 1400.00. 4hrs fri, 9-8pm sat and 9-5 sunday. I expect the same for the 250. So around 1500.00 should cover it. Data collected would be fully shared with people who help support this dyno session. So if you donate atleast 20.00, you are in the full loop. Not all info will be put out on this site. Lets see how many are interested in this. What do you guy's think? Tom Edited by tlowe #1716 (11/11/09 05:31 AM) _________________________ 12 PORT ADVERTISER http://www.inliners.org/Advertisers/index.html trbo writeup http://www.inliners.org/ubbthreads/ubbthreads.php?ubb=showflat&Number=43253&fpart=1
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#53340 - 11/10/09 12:14 PM Re: Dyno day for a 250 [Re: tlowe #1716]
JimRJ JimRJ Active BB Member Registered: 11/01/09 Posts: 50 Loc: Portland, Oregon	Tom: I like the idea of more research and I'll send more money for 230/250 dyno time. I appreciate all your work, Tom. JimRJ
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#53344 - 11/10/09 01:42 PM Re: Dyno day for a 250 [Re: JimRJ]
Randy S. Hager Randy S. Hager Active BB Member Registered: 10/31/06 Posts: 116 Loc: Venus, TX	Since I'm getting my 250 ready for my truck I'm very interested in this one for sure. I'd like to see if EFI-DIY would offer a TBI setup to try out??????????? Randy S. Hager Venus, TX
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#53345 - 11/10/09 02:31 PM Re: Dyno day for a 250 [Re: Randy S. Hager]
popper6 popper6 Active BB Member Registered: 12/15/04 Posts: 218 Loc: La Harpe,IL.	Tom , I didn't get in last time. If your going again- I want in. You say go. I'LL chip in. 1 OL REDNECK _________________________ DARRELL KRAFT I.I.#113
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#53346 - 11/10/09 03:18 PM Re: Dyno day for a 250 [Re: popper6]
sprintbird sprintbird Active BB Member Registered: 12/17/04 Posts: 6 Loc: Ohio	I am in again. Looking forward to the 250 results. Rob
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#53347 - 11/10/09 03:55 PM Re: Dyno day for a 250 [Re: sprintbird]
Al Al Active BB Member Registered: 11/03/05 Posts: 177 Loc: Delta B.C.	I'm in again. As I run a 250, I will be especially interested in your findings. Al
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#53351 - 11/10/09 05:04 PM Re: Dyno day for a 250 [Re: tlowe #1716]
DeuceCoupe DeuceCoupe Active BB Member Registered: 04/17/06 Posts: 288 Loc: Northern CA	Tom, Of course, count me in same as on the 292. Suggestion, if Strokersix has a stout 230 already offered, why not a 230 dyno session? The 250 is right between 230 and 292 (or eh, 301) so would be easy to interpolate the extra 20cid from 230 to 250. And from 230 it's not far down to 194 which some folks still have. With the fewer inches, issues like too much port might come up on the 230 that were not a problem on the 301. Either way, 230 or 250, I'm in.
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#53352 - 11/10/09 05:08 PM Re: Dyno day for a 250 [Re: DeuceCoupe]
Mean buzzen half dozen A.K.A. Hank Mean buzzen half dozen A.K.A. Hank Active BB Member Registered: 09/23/04 Posts: 4546 Loc: Ca	Only thing I am not sure about is the 230 crank,,,does it have all 12 counter weights? If not,,,it might like to vibrate a little too much @ the higher RPMs. I have a 194 steel crank,( same stroke as 230 ), & it does not have 12 counter weights. MBHD _________________________ 12 port SDS EFI
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#53355 - 11/10/09 05:21 PM Re: Dyno day for a 250 [Re: Mean buzzen half dozen A.K.A. Hank]
chevy2inreno chevy2inreno Active BB Member Registered: 08/26/02 Posts: 38 Loc: Reno, Nv.	I'd support a 250 dyno day as well. I suspect most late-model Inliners run the 250 anyway. The 292 is not an easy drop-in for cars, like the 250, for most enthusiasts. My offer to borrow the Clifford 3X2, and Algon, manifolds stands for either engine for a high RPM test. The Clifford intake will need the carbs rebuilt and linkage made and the Algon setup will need everything but the intake, linkage, injectors etc. I don't have a pump or any of the accessories. Maybe some other Inliners can provide carbs or mechanical FI resources.
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#53357 - 11/10/09 06:21 PM Re: Dyno day for a 250 [Re: chevy2inreno]
tlowe #1716 tlowe #1716 12 PORT ADVERTISER Active BB Member Registered: 04/01/04 Posts: 2327 Loc: Dysart, Iowa	Talked with strokersix. He is willing to build a new shortblock 250. It will have a very good lower end with 6" Crower rods and custom aftermarket (light) pistons. I even have a lite weight GM crank that could be used. It would be a flat top piston engine with Zero deck. Chevy2inreno, the 3x2 and algon setup would cost valuable dyno time to get running properly. What we would be looking for is like with the 292, start with stock head / cam and work our way up. Just like most people do when building their ride. I'd be willing to bet the 250 can match or surpass a simular built 292, mainly because it can rev better and that is where HP comes into the equation. Hank, From the cranks I have seen, they are 12 counterweight. Only the earliest of engines got the 6 weight cranks. Tom _________________________ 12 PORT ADVERTISER http://www.inliners.org/Advertisers/index.html trbo writeup http://www.inliners.org/ubbthreads/ubbthreads.php?ubb=showflat&Number=43253&fpart=1
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#53358 - 11/10/09 07:00 PM Re: Dyno day for a 250 [Re: tlowe #1716]
Beater of the Pack Beater of the Pack Active BB Member Registered: 10/06/07 Posts: 2487 Loc: Northern Nevada	I'm in. The two engines should be as much alike as possible so we can compare apples to apples. There will be enough information to keep us jawing for a long time. It is already evident that no matter what evidence is presented it won't convince everyone, but we knew that. Let us know when to send the dough. Beater _________________________ "I wonder if God created man because he was disappointed in the monkey?" Mark Twain
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#53360 - 11/10/09 07:24 PM Re: Dyno day for a 250 [Re: Beater of the Pack]
CNC-Dude #5585 CNC-Dude #5585 Active BB Member Registered: 09/27/08 Posts: 1735 Loc: N. Georgia	Even though the shorter stroke engines dont have near the harmonic problems a 292 has, the fully counterweighted cranks are better in dampening them, and are smoother running. _________________________ There's no such thing as too much cam....only not enough engine! 12 Port Head Manufacturer
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#53362 - 11/10/09 08:05 PM Re: Dyno day for a 250 [Re: CNC-Dude #5585]
Kerry Pinkerton Kerry Pinkerton Active BB Member Registered: 01/04/08 Posts: 123 Loc: Near Huntsville, Alabama	I'm in too. _________________________ Kerry Pinkerton http://wheelingmachines.com
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#53364 - 11/10/09 08:28 PM Re: Dyno day for a 250 [Re: Kerry Pinkerton]
tlowe #1716 tlowe #1716 12 PORT ADVERTISER Active BB Member Registered: 04/01/04 Posts: 2327 Loc: Dysart, Iowa	If we can get 30 people in at 50 apiece or 50 people in at 30 apiece, that would hit the dyno cost target. All the parts are on me as they are ready to go. The short block is Strokersix's. Labor on my part is free and anyone is welcome to come and help. Will try to pick a date in early January to run it. PM me if interested in supporting this and are shy to broadcast it. Also feel free to email me tom@12bolt.com This could be a very interesting test session. Tom _________________________ 12 PORT ADVERTISER http://www.inliners.org/Advertisers/index.html trbo writeup http://www.inliners.org/ubbthreads/ubbthreads.php?ubb=showflat&Number=43253&fpart=1
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#53366 - 11/10/09 09:33 PM Re: Dyno day for a 250 [Re: tlowe #1716]
efi-diy efi-diy Active BB Member Registered: 11/21/04 Posts: 1385 Loc: Calgary Alberta Canada	Beater - hmmm it would be easier shipping wise if your megasquirt was ready... no pesky customs people to deal with. _________________________ 51 GMC 4.2 turbo Can't solved today's problems using the same technology/thinking that created them
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#53367 - 11/10/09 09:49 PM Re: Dyno day for a 250 [Re: efi-diy]
Mean buzzen half dozen A.K.A. Hank Mean buzzen half dozen A.K.A. Hank Active BB Member Registered: 09/23/04 Posts: 4546 Loc: Ca	If anyone has three side draft webers & manifold to lend,,,that would be great,,,,,using that intake & carbs is AWESOME!!!!!! Talk about torque increase!!! MBHD _________________________ 12 port SDS EFI
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#53368 - 11/10/09 09:55 PM Re: Dyno day for a 250 [Re: efi-diy]
CNC-Dude #5585 CNC-Dude #5585 Active BB Member Registered: 09/27/08 Posts: 1735 Loc: N. Georgia	Testing a 250 as opposed to a 230 might give those thinking of building a 230 the incentive to step up and go with the extra cubes. Since the difference in the two engines is the stroke, it might offer more of a torque advantage than they realize. What to do about those interested in a 194 is hard to say. With the large selection in the different performance levels of heads being tested, im sure a head for all engine sizes is available for the 194-292 to suit the needs of everyone wanting to build a mild or wild engine combo. _________________________ There's no such thing as too much cam....only not enough engine! 12 Port Head Manufacturer
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#53370 - 11/10/09 10:15 PM Re: Dyno day for a 250 [Re: efi-diy]
Beater of the Pack Beater of the Pack Active BB Member Registered: 10/06/07 Posts: 2487 Loc: Northern Nevada	Originally Posted By: efi-diy Beater - hmmm it would be easier shipping wise if your megasquirt was ready... no pesky customs people to deal with. Pesky customs people? Marc they keep us safe! No telling what would be shipped in here if they weren't looking out for us. (real beer) But one way or another I see I'll get no rest until I finish the Megasquirt. So I'll get back to work on it and if there's interest in it I could box it up. Beater (one of many Toms) _________________________ "I wonder if God created man because he was disappointed in the monkey?" Mark Twain
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#53371 - 11/10/09 10:36 PM Re: Dyno day for a 250 [Re: Beater of the Pack]
justnwynn justnwynn Active BB Member Registered: 11/03/09 Posts: 5 Loc: Bossier City, LA	i've got 250 i'm about to put into my truck. i missed the 292 dyno, but i'll be in for this one. just let me know. will the block be bored? or did i miss that?
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#53373 - 11/11/09 04:43 AM Re: Dyno day for a 250 [Re: justnwynn]
Winter Winter Active BB Member Registered: 08/27/06 Posts: 206 Loc: North Carolina	I'll send funds for the 250 dyno also, as I did for the 292 dyno. Personally, I'd like to see some other camshafts tested. Comp Cams 260H (0.489 lift/212 0.050 duration) so often mentioned as a recommendation for the 250. Isky 256 Supercam (0.492 lift/202 0.050 duration) or Schneider 256H (0.470 lift/204 0.050 duration) for those wanting a little more low end torgue. Can exhaust systems be tested? Original stock cast manifold. 292 cast manifold Langdon cast headers Clifford short tube headers Long tube headers
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#53374 - 11/11/09 05:26 AM Re: Dyno day for a 250 [Re: Winter]
tlowe #1716 tlowe #1716 12 PORT ADVERTISER Active BB Member Registered: 04/01/04 Posts: 2327 Loc: Dysart, Iowa	Exhaust is a hard thing to test. It takes time and money to make the couplings/ pipes. The headers were relatively easy. I am in for the cams, Can anybody supply those? Just from the #'s the comp 260H should be a good street choice. Even in a 292. Remember they need timing gears and thrust plates, I can also get, but they add additional cost. Beater/EFI, There are a couple problems with the TBI thing. First is the fuel system, this room is not setup yet for the fuel pressure needed or the return line. 2nd would eat valuable time to tune the TBI. 3rd there would be no real power gain over a carb. Once tuned, probably more torq. Hank, I agree, to test a weber setup would be great, who has one and also has what is needed to tune them? _________________________ 12 PORT ADVERTISER http://www.inliners.org/Advertisers/index.html trbo writeup http://www.inliners.org/ubbthreads/ubbthreads.php?ubb=showflat&Number=43253&fpart=1
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#53375 - 11/11/09 05:33 AM Re: Dyno day for a 250 [Re: Winter]
Gabbyp #865 Gabbyp #865 Active BB Member Registered: 03/26/09 Posts: 7 Loc: North Carolina	I will also be in for the 250 dyno runs as I was for the 292 dyno runs. Just say when its a go and its in the mail.
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#53376 - 11/11/09 06:28 AM Re: Dyno day for a 250 [Re: Gabbyp #865]
JOE LARSON JOE LARSON Active BB Member Registered: 01/03/02 Posts: 124 Loc: VA BCH, VA	Tom, Me too. Count me in for fifty again, and remember, I've got that Comp Cams 268H w/ plate, wheel, & even lifters if you want to try it. wish I could swap it for 'new' Chevelle oil pickup tube..........had more interference problems so I/m out and opened up again. This time #3 has nearly rubbed a hole in the pipe. _________________________ JOE II# 3486 '48 FLEETLINE AERO http://s639.photobucket.com/albums/uu117/lars62go/
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#53378 - 11/11/09 07:47 AM Re: Dyno day for a 250 [Re: JOE LARSON]
tlowe #1716 tlowe #1716 12 PORT ADVERTISER Active BB Member Registered: 04/01/04 Posts: 2327 Loc: Dysart, Iowa	Sorry to hear that , Joe. I remember when doing mine, had to really work on getting the clearance for the crank and rods. There is one of the cams, Comp 268H Who has a Comp 260H? Or the other 2 grinds? Tom _________________________ 12 PORT ADVERTISER http://www.inliners.org/Advertisers/index.html trbo writeup http://www.inliners.org/ubbthreads/ubbthreads.php?ubb=showflat&Number=43253&fpart=1
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#53379 - 11/11/09 08:06 AM Re: Dyno day for a 250 [Re: tlowe #1716]
ACH57 ACH57 Active BB Member Registered: 05/21/07 Posts: 42 Loc: Clarkdale, AZ	I'm in for this. I would vote for testing a 230, since I have one myself. It's also in between the 250 and 194. In my case, I have a good running 230 with good compression and oil pressure so I will be doing bolt ons-head, intake, cam-before I do a complete rebuild.
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#53380 - 11/11/09 08:51 AM Re: Dyno day for a 250 [Re: tlowe #1716]
CNC-Dude #5585 CNC-Dude #5585 Active BB Member Registered: 09/27/08 Posts: 1735 Loc: N. Georgia	Originally Posted By: tlowe #1716 Hank, I agree, to test a weber setup would be great, who has one and also has what is needed to tune them? Tom, we ran (3)sidedraft Webers on Cotton's engine for almost a whole season. Even though they had real sharp throttle response and excellent idle characteristics, and allowed us to set a few class and division records, the (3) Holley 2 bbls. we switched over to made almost 40 HP more. _________________________ There's no such thing as too much cam....only not enough engine! 12 Port Head Manufacturer
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#53382 - 11/11/09 09:39 AM Re: Dyno day for a 250 [Re: Winter]
DeuceCoupe DeuceCoupe Active BB Member Registered: 04/17/06 Posts: 288 Loc: Northern CA	I very much like Winter's suggestion of dyno testing exhaust systems if that is possible. Maybe once the carb jetting is dialed in for the current headers, it might be ok to skip the sensors if that is making it hard to test exhaust systems. There might be some real surprises in comparing the various exhaust iron to exhaust headers. Maybe even a test of the stock 1v carb and intake too?
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#53384 - 11/11/09 11:16 AM Re: Dyno day for a 250 [Re: tlowe #1716]
efi-diy efi-diy Active BB Member Registered: 11/21/04 Posts: 1385 Loc: Calgary Alberta Canada	Tom, Re TBI For a dyno pull the only real tuning required is idle, off idle tranisiton to WOT and WOT. The mid-range normally used for driving is not seen during a pull except for the off idle trasistion. If the AFR from previous pulls on a carb were entered into the AFR target table and a wideband O2 sensor used to gather actual AFR data by logging the pull with the MS tuning interface you would only need 2-3 pulls to have a fully tuned system. The tuning process involves data logging a pull, then use the fuel curve optimization s/w. Once the optimization application on the laptop is running then the datalog, and tuneup file for the logged run are opened. The tuneup file contains the fuel table, AFR target table and spark table. Once opened the optimization anaylsis is run which will adjust the fuel table rich or lean based on the AFR target table and the datalog. The resulting fuel table is then loaded into the EFI controller and a confirmation dyno pull made with logging enabled. Repeat the above process once and you have a fully tuned system. This whole process would take no more than 15 min's including the 2 dyno pulls. Idle and off idle tuning does not have to be precise and can be done in 2-3 min's. If the AFR is a bit off at idle/off idle it doesn't matter. As for the fuel system I think Beater has the complete tank/pump/lines ready to roll. If it wasn't so difficult to get there from here I'd come down to handle the tuning. Edited by efi-diy (11/11/09 11:22 AM) _________________________ 51 GMC 4.2 turbo Can't solved today's problems using the same technology/thinking that created them
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#53392 - 11/11/09 04:41 PM Re: Dyno day for a 250 [Re: efi-diy]
jalopy45 #4899 jalopy45 #4899 Active BB Member Registered: 04/09/06 Posts: 665 Loc: Oregon Outback	I'm in again for $100.00, Talked to Tom Langdon (oredering more parts again) and he wants in too. He didn't know about the 292 until close to the date so he would like to get an advance notice of the date when it's decided. _________________________ '45 Ford PU '63 Nova Wagon 250 4 spd. '63 MGB GT Ecotec Altered
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#53393 - 11/11/09 06:05 PM Re: Dyno day for a 250 [Re: CNC-Dude #5585]
Mean buzzen half dozen A.K.A. Hank Mean buzzen half dozen A.K.A. Hank Active BB Member Registered: 09/23/04 Posts: 4546 Loc: Ca	Originally Posted By: CNC-Dude #5585 Originally Posted By: tlowe #1716 Tom, we ran (3)sidedraft Webers on Cotton's engine for almost a whole season. Even though they had real sharp throttle response and excellent idle characteristics, and allowed us to set a few class and division records, the (3) Holley 2 bbls. we switched over to made almost 40 HP more. Just a question,,,how would you think the 3 2 bbl Holley carbs & intake would work on the street? What was the RPM range of that set-up? MBHD _________________________ 12 port SDS EFI
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#53395 - 11/11/09 06:14 PM Re: Dyno day for a 250 [Re: Mean buzzen half dozen A.K.A. Hank]
tlowe #1716 tlowe #1716 12 PORT ADVERTISER Active BB Member Registered: 04/01/04 Posts: 2327 Loc: Dysart, Iowa	He does make a good point, I say that chuckling. We are aiming at street engines. Jalopy, I will see if Tom can lone a set of the cast headers for dyno use. We did find the EGT never got high, so no need to add the temp bungs. Still would need to bend up pipes. EFI, I am still not sold on trying a TBI. And you know EFI is nothing new to me. EFI is awesome for tuning. It would be alot more work and not sure if anything would be proved. It is proven on many Vthings how much power they can support. _________________________ 12 PORT ADVERTISER http://www.inliners.org/Advertisers/index.html trbo writeup http://www.inliners.org/ubbthreads/ubbthreads.php?ubb=showflat&Number=43253&fpart=1
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#53396 - 11/11/09 06:21 PM Re: Dyno day for a 250 [Re: Mean buzzen half dozen A.K.A. Hank]
CNC-Dude #5585 CNC-Dude #5585 Active BB Member Registered: 09/27/08 Posts: 1735 Loc: N. Georgia	Well they are only available in 350 CFM as the smallest, so even(3) of them would probably be to big for most street 6's. However, a lot of the older vintage hotrodders use the small Rochester 2 bbls. with 2 or 3 carbs on inlines, so maybe that could be a possibility for a multi-carb setup that would be streetable and not to much CFM. They were like the old tri-power GTO's back in the 60's. I forgot also, that the Webers will fit under the hoods of most cars since their side draft, the Holley's will make you have to cut a hole in the hood and use a hood scoop in some cars. _________________________ There's no such thing as too much cam....only not enough engine! 12 Port Head Manufacturer
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#53397 - 11/11/09 06:28 PM Re: Dyno day for a 250 [Re: CNC-Dude #5585]
Mean buzzen half dozen A.K.A. Hank Mean buzzen half dozen A.K.A. Hank Active BB Member Registered: 09/23/04 Posts: 4546 Loc: Ca	What was the RPM range for that 3 2 bbl set-up? MBHD _________________________ 12 port SDS EFI
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#53399 - 11/11/09 06:39 PM Re: Dyno day for a 250 [Re: Mean buzzen half dozen A.K.A. Hank]
CNC-Dude #5585 CNC-Dude #5585 Active BB Member Registered: 09/27/08 Posts: 1735 Loc: N. Georgia	In the Comp rear engine dragster, it was launched at around 5000 RPM and shifted at 7200. _________________________ There's no such thing as too much cam....only not enough engine! 12 Port Head Manufacturer
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#53400 - 11/11/09 07:12 PM Re: Dyno day for a 250 [Re: CNC-Dude #5585]
efi-diy efi-diy Active BB Member Registered: 11/21/04 Posts: 1385 Loc: Calgary Alberta Canada	Tom I think you will pick up power from better fuel control. That said you can only lead a horse to water..... _________________________ 51 GMC 4.2 turbo Can't solved today's problems using the same technology/thinking that created them
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#53403 - 11/11/09 08:10 PM Re: Dyno day for a 250 [Re: efi-diy]
tlowe #1716 tlowe #1716 12 PORT ADVERTISER Active BB Member Registered: 04/01/04 Posts: 2327 Loc: Dysart, Iowa	The EFI is just too much of a pain to do. There are many more important things that need to be swapped and checked. A glick with a EFI unit could cost a 1/2 day. That I am not willing to sacrifice. I run EFI on my car and know it is the cats meow for tuning, just not willing to do it on a motor that is designated to test parts and theories. By the way, what do you do with that horse once you lead him to water? _________________________ 12 PORT ADVERTISER http://www.inliners.org/Advertisers/index.html trbo writeup http://www.inliners.org/ubbthreads/ubbthreads.php?ubb=showflat&Number=43253&fpart=1
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#53405 - 11/12/09 03:56 AM Re: Dyno day for a 250 [Re: tlowe #1716]
Twisted6 I.I #3220 Twisted6 I.I #3220 Lump Port head builder Active BB Member Registered: 07/04/00 Posts: 3833 Loc: EdgeWater FL. USA I.I. # 3220	You let him stand there an figure it out himself. duh. lmao _________________________ Larry/Twisted6 #3220 }[oooooo] $\:\)$ Adding CFM adds boost $\:\)$ $\:o$ God doesn't like ugly.
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#53406 - 11/12/09 04:38 AM Re: Dyno day for a 250 [Re: Twisted6 I.I #3220]
Sam Welch Sam Welch Active BB Member Registered: 03/17/01 Posts: 240 Loc: Castle Valley, UT	I prefer my horses under the hood. _________________________ '38 Stude/292
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#53408 - 11/12/09 07:14 AM Re: Dyno day for a 250 [Re: Sam Welch]
DeuceCoupe DeuceCoupe Active BB Member Registered: 04/17/06 Posts: 288 Loc: Northern CA	On the 3-2v setups: They may not be too big although admittedly they take a lot of tuning. As you probably know, the 2v carbs' CFM are rated at 3.0" Hg, whereas 4v CFM are (usually) rated at 1.5" Hg. So, a trio of 350cfm Holleys, if rated by the 4v rating, does not flow 3*350=1050cfm, but rather about 750cfm total. It can get even better: The smallest 2300 Holley 2v I've found is not the "350" (about 250cfm using 4v rating) but rather the 1-1/16" venturi Holley which I rate at about "265" cfm, or 190cfm on the 4v rating. Three of these carbs would give 570cfm with the 4v rating which is just about the size Tom used on the 292 tests. Not so bad. I have one of these carbs, it is List 2463, a factory AMC application. These small 2300's dont exactly grow on trees but they are around. As you said, the little Rochesters are similar. The 283-2v carbs are pretty common and were about "278" cfm (2v rating) or 184cfm on the 4v rating. So a trio of them is only 552cfm. With three of either the smallest Holley 2300s or the small Rochester 2g carbs the 250 dyno engine should be happy enough, but they are still time consuming to set up unless somebody has already dialed a setup in on their own street engine. I'm glad the 250 dyno will give us a "Part 2", so much data will come out of this even if Tom can't do all the ideas.
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#53410 - 11/12/09 08:26 AM Re: Dyno day for a 250 [Re: DeuceCoupe]
Beater of the Pack Beater of the Pack Active BB Member Registered: 10/06/07 Posts: 2487 Loc: Northern Nevada	One of our local guys runs 3 Webbers on his 292. I'll talk to him at our meeting Saturday. Maybe the shot at fame would get him to switch for a while. Probably get some of the members to kick in beer and help with the switch. It'll be tough! Edited by Beater of the Pack (11/12/09 08:27 AM) _________________________ "I wonder if God created man because he was disappointed in the monkey?" Mark Twain
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