#54792 - 01/11/10 06:26 AM
Re: Dyno day for a 250
[Re: jalopy45 #4899]
|
Mean buzzen half dozen A.K.A. Hank
Active BB Member
 
Registered: 09/23/04
Posts: 4546
Loc: Ca
|
Just curious Hank, did you personally ever deal with Leelites?
No, I choose not to get a headache, but my friend has &,,,,,,,,, coo-coo.
_________________________
12 port SDS EFI
|
|
Top
|
|
|
|
#54803 - 01/11/10 04:42 PM
Re: Dyno day for a 250
[Re: Beater of the Pack]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
Yep, the tests will be going on. This weather has slowed me down. Had to clear my shop to get the F450 4X4 flatbed in there. Talk about leaving the freezer door open. That truck has a winters worth of ice and snow stuck to it, and winter is only about 2 weeks old! It took over 24 hrs to thaw it out. Now to change the fuel pump.
Next the 250 will go in the shop and be dismembered for rebuild. Only the one divided head to work on also. The rest of the parts are still ready from the 292 dyno tests.
Contributions are coming in. Got one from SOB, Bill Mulholland from down in Texas, sounds like they are also getting a taste of winter (not liking it much either).
If anyone is interested in helping, here is the wish list. Possibly 3 cams from Compcams 3 cam timing gears from cloyes funds to help pay for dyno time
If anyone wants contribute funds, here are the 2 ways
Paypal to tom@12bolt.com (send it as a gift and they don't seem to take out fees)
or by mail
Tom Lowe 3063 200th st Dysart, Iowa 52224
Telephone 319 476 2172 evenings 6-10 pm
Anyone who contributes get the data collected from the tests. For the 292 dyno tests, over 50 contributors helped make it happen. Some from far away in other countries. Contributors are also kept confidential. I do have a 250 dyno list of contributors started. Thanks again to those who have allready.
Now out to change that fuel pump. Tom
Fuel pump is done now, fuel at 50 psi really helps make that diesel roar.
Edited by tlowe #1716 (01/11/10 07:19 PM)
|
|
Top
|
|
|
|
#54808 - 01/11/10 07:52 PM
Re: Dyno day for a 250
[Re: tlowe #1716]
|
GMCCORBETT
Active BB Member
Registered: 07/08/02
Posts: 34
Loc: Englewood, CO USA
|
Tom - Just wondering how your magazine article was progressing. Will it run before the 250 tests or will you wait until after they are done?
Bob
|
|
Top
|
|
|
|
#54819 - 01/12/10 10:41 AM
Re: Dyno day for a 250
[Re: GMCCORBETT]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
Bob, The article is going good, most of that is in Scott's hands now. He is a much better writer than I.
Doubt it will be in a mag before Dynoing the 250. From reading articles in many mags, they seem to be about 3-4 months slow. Tom
|
|
Top
|
|
|
|
#54840 - 01/13/10 04:38 AM
Re: Dyno day for a 250
[Re: Mean buzzen half dozen A.K.A. Hank]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
Do not know the brand, they are just not a familiar carb to me. Believe they are 45 mm.
As far as the 194 head. Not going to build any with small valves. The 1.84 valve in that head will not flow as well as a 1.84 in a open chamber head. Will rerun the one run on the 292. May open the chambers some. To match a open chamber heads clearance, might as well started with a open chamber head.
I personally think there is more power to be had with different techniques than a "194" head. Which has also been proven to me with flow tests and dyno.
Still open to someone supplying a prepped "194"head. Tom
|
|
Top
|
|
|
|
#54936 - 01/16/10 12:38 PM
Re: Dyno day for a 250
[Re: tlowe #1716]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
The 250 is definately started now. The boy and I tore down the donor 250 today and took it in to be hot tanked. Next the machine work will start. The motor was a 76' 250 with a 1bbl integrated head. The head is in the iron pile now. It had to be as heavy as the block!
Recieved the 3 weber side draft on Friday. Carbs are also coming.
A few more contributions have came in and thankyou's to you guy's.
Taking pictures as we go on the teardown and build. Tom
|
|
Top
|
|
|
|
#55066 - 01/23/10 07:36 AM
Re: Dyno day for a 250
[Re: jalopy45 #4899]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
Jalopy, Not sure on a date yet. Just yesterday( Fri) the block was hot tanked and magnafluxed. That all looks good. Preliminary checks indicate a .040 overbore. Block will be decked and bored next week, then order the pistons. Crank will need to be turned and balanced. The dyno has a Pontiac on it now. The operator was teasing me and said when running the Pontiac, the dyno popped up a message stating to test only 1 inline 6 at a time as the torq reading was too high. The Pont is a big cube sucker and was pegging the tq beyond the 500 ft pd mark closer to 600 ft pnds.
The lower end should go together relatively fast. The top end stuff is still ready from the 292 tests. Still aiming for later feb. Anyone interested in coming here to help? I know my local club will. Maybe some of you guy's could come too. Tom
|
|
Top
|
|
|
|
#55245 - 01/28/10 05:33 PM
Re: Dyno day for a 250
[Re: tlowe #1716]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
Pistons ordered today, block did bore to .040. Deck height measured 9.135 so ordered pistons for a zero deck and pure flat tops. Crank was deburred and going into the grinder on Fri. Tom
|
|
Top
|
|
|
|
#55503 - 02/06/10 04:54 PM
Re: Dyno day for a 250
[Re: Beater of the Pack]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
Recieved the OER/Weber carbs and extra parts from 1/2 way around the world! He also sent a new side draft intake. Now that is stepping up to help out with the 250 dyno tests. Will be interesting to see how it runs with this setup compared to the normal parts. Pistons should be here in a 1 1/2 weeks. Tom
|
|
Top
|
|
|
|
#55549 - 02/11/10 07:33 PM
Re: Dyno day for a 250
[Re: Mean buzzen half dozen A.K.A. Hank]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
One reason not to run the weber type carbs. No choke. Would not work well in my climate. He sent the carbs with 40mm chokes? (venturis). Also 36mm and 32mm.
Got the crank back. It is turned .010/.010. I deburred it before taking it in, oil holes are all chamfered now. Really looks nice! Cam, rod and main bearings are all ordered. Crank is getting balanced next. Got the new oil pump, will disassemble and deburr it.
Block work includes: Plugging the oil bypass (like full oil filtration all the time), plug the front timing gear oil spout. Deburr the internal block. Chamfer the cylinders near the intake/ exh valves ( better flow).
Get a couple more cams ready with timing gears.
When pistons get here, get rods/ pistons balanced up.
Winter is going fast if I keep this up. Tom
Edited by tlowe #1716 (02/11/10 07:35 PM)
|
|
Top
|
|
|
|
#55550 - 02/11/10 09:12 PM
Re: Dyno day for a 250
[Re: tlowe #1716]
|
Mean buzzen half dozen A.K.A. Hank
Active BB Member
 
Registered: 09/23/04
Posts: 4546
Loc: Ca
|
Some Webers have a cold start circuit (choke), others don't, it is very easy to flood the engine and wet plugs using the cold start mechanism, as it very crude in operation. The accepted technique for cold starting is as follows:-
Allow the float chambers to fill if you have an electric pump, this should take about 5-10 seconds, fully depress the accelerator rapidly four times, then on a light throttle, turn the engine over, if it does not start immediately, repeat the procedure three times. The engine should fire, but may need 'nursing' for a minute or two before it will idle, gentle prodding of the accelerator should keep it alive long enough for it to warm up. If the engine does not fire within three attempts, then try five or six pumps. If this does not work, depress the accelerator fully and hold it open while turning the engine over for 5 to 15 seconds, then close the accelerator and try again.
A different guys quote: And cold starts are no problem since they have an accellerator pump and a cold start ... My Alfa with webers started easily in zero deg weather. ... That aside, a properly tuned IR set-up using Weber DCOE, IDA, ...
_________________________
12 port SDS EFI
|
|
Top
|
|
|
|
#55559 - 02/12/10 04:09 PM
Re: Dyno day for a 250
[Re: panic]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
Enough about the choke. This engine will start just fine in a controlled dyno cell enviroment.
More interested in power output. Tom
|
|
Top
|
|
|
|
#55562 - 02/13/10 10:19 AM
Re: Dyno day for a 250
[Re: tlowe #1716]
|
Herb I.I.#3241
Active BB Member
Registered: 12/16/06
Posts: 37
Loc: Covington La.
|
Tom, I thought my 68 250 block already was full flow filterd! also why the timing gear oil blockoff. Herb 3241
_________________________
68 Camaro 250 Clifford intake headers Holly 700r4 3:08 Cruiser I.I.3241
|
|
Top
|
|
|
|
#55565 - 02/13/10 01:54 PM
Re: Dyno day for a 250
[Re: Herb I.I.#3241]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
Herb, These series of engines are full flow filtered. But at startup, with thick oil viscousity, there is a bypass that can and will open. This will allow unfiltered oil to bypass the filter. GM put this in so that when dummy's did not change their oil and the filter became plugged, the motor would still have oil pressure.
I plug the front oil spout to keep more oil for the crank/ rods. Later Gm engines did not use this feature. Plenty of oil flying around down there. Tom
|
|
Top
|
|
|
|
#55591 - 02/15/10 08:02 AM
Re: Dyno day for a 250
[Re: Turbo-6]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
Sent a email out to all contributors. It is the schedule of tests to be run. If anyone was missed please contact me.
There is one recieved over the weekend not added to the list. Will be this evening.
Got a bunch of test scheduled. Have atleast 7 cams to choose from and 4 different head configurations. Testing a divided port and maybe will even turbo it! Blow thru down and dirty. Tom
Any requests?
|
|
Top
|
|
|
|
#55656 - 02/19/10 07:56 PM
Re: Dyno day for a 250
[Re: tlowe #1716]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
Had a present sitting on the porch today! 6 shiny forged pistons all wrapped up pretty. Looks like I have some work to get done now. Tom
|
|
Top
|
|
|
|
#55665 - 02/20/10 01:16 PM
Re: Dyno day for a 250
[Re: jalopy45 #4899]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
Just got back from the shop. Block is now deburred and the cylinders are chamfered. Then worked on some heads. Block will get honed next with a tq plate and head studs. then cleaned again for final assy.
Jalopy, I sent the email out the same as with the 292 tests. Checked and you are on the list. Will send out again. Subject of email will be 250 dyno day.
Hank, Took plenty of pic's, wife went to a program and took the camera. Will get some posted later. Tom
|
|
Top
|
|
|
|
#55667 - 02/20/10 03:10 PM
Re: Dyno day for a 250
[Re: tlowe #1716]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
Here are some pics of parts and some cylinder reliefs. Tom





|
|
Top
|
|
|
|
#55669 - 02/20/10 04:57 PM
Re: Dyno day for a 250
[Re: panic]
|
tlowe #1716
12 PORT ADVERTISER
Active BB Member
  
Registered: 04/01/04
Posts: 2327
Loc: Dysart, Iowa
|
Please ask questions in layman terms.
The top ring land is down .300 and the chamfers go down .150. Should be no ring sealing problems. If you look at the way the valves are located offcenter of the cylinder, these chamfers will remove the sharp 90 degree edge the airflow hits leaving the intake valve. Tom
|
|
Top
|
|
|
|
Moderator: Webmaster
|
|