Houston, we got a problem...
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Joined: Jul 2001
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
Houston, we got a problem...
I started assembling my Race car again and installed engine and transmission (powerglide) together... The powerglide came out of a 7 second C4 (backhalved) and I never thought anything about that.. However, the dedenbear case of the Glide has the transmission mount setup for a C4, so it's too far forward for my C3.. It's not as big of a problem as I was going to have a bolt on cross member fabricated anyways.. and now I'll have it fabricated for the different transmission mount.. The only thing that sucks is that I can't run the car before that is done.. When I'll have the crossmember made, I'll also have the rollbar upgraded to a rollcage etc. etc. and it might take a few more weeks until that is done... So that could mean that I won't be able to run before fall.. The chassis shop is very busy as they do great for for low prices..
Last edited by GrandSportC3; Jul 28, 2007 at 02:17 PM.
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The 'Glide uses a mount location like a regular 4 speed, or a T-350...old style stuff. Your 200R4 mount I believe is scooted back some in stock form..pretty close to a T-400.
Can you just take a flat steel plate and drill 4 holes in it and make an extension to join the trans mount to the crossmember? Might have to make a bend or two...something similar to how a stock C-3 or C-2 trans mount is made maybe? Look under your yellow C-3 to see if something like that will work.
I bet if you look around at the trans swap places you can find a bracket to bolt it all together.
JIM
Can you just take a flat steel plate and drill 4 holes in it and make an extension to join the trans mount to the crossmember? Might have to make a bend or two...something similar to how a stock C-3 or C-2 trans mount is made maybe? Look under your yellow C-3 to see if something like that will work.
I bet if you look around at the trans swap places you can find a bracket to bolt it all together.
JIM
Thread Starter
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Joined: Jul 2001
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From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
The 'Glide uses a mount location like a regular 4 speed, or a T-350...old style stuff. Your 200R4 mount I believe is scooted back some in stock form..pretty close to a T-400.
Can you just take a flat steel plate and drill 4 holes in it and make an extension to join the trans mount to the crossmember? Might have to make a bend or two...something similar to how a stock C-3 or C-2 trans mount is made maybe? Look under your yellow C-3 to see if something like that will work.
I bet if you look around at the trans swap places you can find a bracket to bolt it all together.
JIM
Can you just take a flat steel plate and drill 4 holes in it and make an extension to join the trans mount to the crossmember? Might have to make a bend or two...something similar to how a stock C-3 or C-2 trans mount is made maybe? Look under your yellow C-3 to see if something like that will work.
I bet if you look around at the trans swap places you can find a bracket to bolt it all together.
JIM
Thread Starter
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
The only good thing is that the power band is very wide.. I got approx.. 580 - 598 HP between 5500 and 7000 RPM.. They were running 1 3/4 inch headers and I'm running 1 7/8 which should also be good for a little bit.
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From: Pettis Performance 565 with two stages of Nitrous Supply nitrous 1.082, 4.61 at 155, 7.17 at 192
Something is not right Oliver............I just don't see how that motor can make such low numbers at such low rpms, then again maybe those heads can't feed a 434.
Can you post your cam specs again ?
Did you put fresh valve springs on the heads ? How many passes are on those springs? Those are the same heads that came off the 406 right ??
I would pull the valve covers off to see if there are some bent pushrods.
How did the motor act, did it idle fine, pull smooth through the rpms range??
Of course there is always the fact that dyno's are sorta like women........
If you do not find anything then I guess the track will have to be the real dyno.
One more thing I would do is post the entire engine build specs and dyno sheet over on speed talk.com. There are some very knowledgable and helpful guys over there who may be able to help you out.
Can you post your cam specs again ?
Did you put fresh valve springs on the heads ? How many passes are on those springs? Those are the same heads that came off the 406 right ??
I would pull the valve covers off to see if there are some bent pushrods.
How did the motor act, did it idle fine, pull smooth through the rpms range??
Of course there is always the fact that dyno's are sorta like women........
If you do not find anything then I guess the track will have to be the real dyno.
One more thing I would do is post the entire engine build specs and dyno sheet over on speed talk.com. There are some very knowledgable and helpful guys over there who may be able to help you out.
Last edited by 69 N.O.X. RATT; Jul 29, 2007 at 09:49 AM.
Thread Starter
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Joined: Jul 2001
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
Something is not right Oliver............I just don't see how that motor can make such low numbers at such low rpms, then again maybe those heads can't feed a 434.
Can you post your cam specs again ?
Did you put fresh valve springs on the heads ? How many passes are on those springs? Those are the same heads that came off the 406 right ??
I would pull the valve covers off to see if there are some bent pushrods.
How did the motor act, did it idle fine, pull smooth through the rpms range??
Of course there is always the fact that dyno's are sorta like women........
If you do not find anything then I guess the track will have to be the real dyno.
One more thing I would do is post the entire engine build specs and dyno sheet over on speed talk.com. There are some very knowledgable and helpful guys over there who may be able to help you out.
Can you post your cam specs again ?
Did you put fresh valve springs on the heads ? How many passes are on those springs? Those are the same heads that came off the 406 right ??
I would pull the valve covers off to see if there are some bent pushrods.
How did the motor act, did it idle fine, pull smooth through the rpms range??
Of course there is always the fact that dyno's are sorta like women........
If you do not find anything then I guess the track will have to be the real dyno.
One more thing I would do is post the entire engine build specs and dyno sheet over on speed talk.com. There are some very knowledgable and helpful guys over there who may be able to help you out.
Motor acted normal, no noises.. Fired right up and pulled smooth through the RPM range.. I have a video of one of the pulls and might post it shortly.
Safety Car
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From: Pettis Performance 565 with two stages of Nitrous Supply nitrous 1.082, 4.61 at 155, 7.17 at 192
I'll tell you Oliver...............somin just ain't right. Who ported the heads? I went over to Rehermorrison's web site and looked at thier 412 cu in. small block; it makes 75+ hp over what yours supposedly made with a little less cam, same heads............pretty much the same motor other than that. RM's dyno is notoriously conservative.
I guess before I got too upset I would run the thing and see what it does. If it out runs the 406 off the trailer then you will now the dyno numbers where a little skewed.
I heard about your tranny issues..........bummer, welcome to the world of race cars !!!! I am lucky I have one friend is a good welder and decent fabricator and another who is awesome, designs and builds stuff for Harley, is presently building his own tube frame Nova from the ground up. It sure helps having that kind of help around. I can weld just well enough to make two pieces of steel stick together (probably) but it ain't pretty.
I guess before I got too upset I would run the thing and see what it does. If it out runs the 406 off the trailer then you will now the dyno numbers where a little skewed.
I heard about your tranny issues..........bummer, welcome to the world of race cars !!!! I am lucky I have one friend is a good welder and decent fabricator and another who is awesome, designs and builds stuff for Harley, is presently building his own tube frame Nova from the ground up. It sure helps having that kind of help around. I can weld just well enough to make two pieces of steel stick together (probably) but it ain't pretty.
Last edited by 69 N.O.X. RATT; Jul 29, 2007 at 10:22 AM.
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Le Mans Master
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From: League City Tx
Damn Oliver, that sux bro...I know you had high expectations for it. I am not sure what that sucker should make but....I would have guessed at least 650....
I mean there are a lot of 400-415" street motors making 550crank hp and NO DOUBT with all the hardware yours has, it should make way more then 50hp more...
I would just take it to the track and see what it does.. track tune it and go from there..
Personally though, I don't think 316cfm intake flow is near enough for 434" breathing through a 288*@.050 cam.... Either the heads are too small or the cam is too big.... But I am no builder so......what the F do I know.
I mean there are a lot of 400-415" street motors making 550crank hp and NO DOUBT with all the hardware yours has, it should make way more then 50hp more...
I would just take it to the track and see what it does.. track tune it and go from there..
Personally though, I don't think 316cfm intake flow is near enough for 434" breathing through a 288*@.050 cam.... Either the heads are too small or the cam is too big.... But I am no builder so......what the F do I know.
Le Mans Master
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From: League City Tx
OH ALSO, I was just looking at the AFR...are those numbers right? 13.78-1 AFR?? why the F would they leave it that lean?? Dude you got 20+hp in jetting alone... That thing should be 12.5-12.8-1. I wouldn't run it with it that lean...thats a melted piston waiting to happen. I can't believe they even made full pulls with it that lean on a 14-1 comp race motor...
Safety Car
Joined: Aug 2001
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From: Pettis Performance 565 with two stages of Nitrous Supply nitrous 1.082, 4.61 at 155, 7.17 at 192
OH ALSO, I was just looking at the AFR...are those numbers right? 13.78-1 AFR?? why the F would they leave it that lean?? Dude you got 20+hp in jetting alone... That thing should be 12.5-12.8-1. I wouldn't run it with it that lean...thats a melted piston waiting to happen. I can't believe they even made full pulls with it that lean on a 14-1 comp race motor...
Race Director
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From: Millington Illinois
St. Jude Donor '08-'09
Need a good tuner. Too lean and looks like the valve timing could be off. That thing should just really be starting to pull hard where your hp drops off. Maybe your heads aren't flowing well enough. AFR 195's Competition ported flow 300 and 225 @ .600 lift. Your trying to feed a 434 14 to 1 motor with less than that if your flow #s are at .700 lift. Did you dial in the ignition timing on the dyno too? A lot of motors don't put out the #s you would think they should on the first couple runs. Seating the rings might be good for 20 HP on a 14 to 1 motor. Proper A/F mix is critical, especially with that kind of compression. The small primary tubes on the headers could be holding you back. A lot of seemingly minor things can combine to cost you a lot of power. A 14 to 1 motor will be finicky to tune properly and may take 15 or 20 runs or more to dial everything in just right with a real good tuner. Good luck!
Last edited by 63mako; Jul 29, 2007 at 11:30 AM.
Thread Starter
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
OH ALSO, I was just looking at the AFR...are those numbers right? 13.78-1 AFR?? why the F would they leave it that lean?? Dude you got 20+hp in jetting alone... That thing should be 12.5-12.8-1. I wouldn't run it with it that lean...thats a melted piston waiting to happen. I can't believe they even made full pulls with it that lean on a 14-1 comp race motor...
Thread Starter
Team Owner
Joined: Jul 2001
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
Need a good tuner. Too lean and looks like the valve timing could be off. That thing should just really be starting to pull hard where your hp drops off. Maybe your heads aren't flowing well enough. AFR 195's Competition ported flow 300 and 225 @ .600 lift. Your trying to feed a 434 14 to 1 motor with less than that if your flow #s are at .700 lift. Did you dial in the ignition timing on the dyno too? A lot of motors don't put out the #s you would think they should on the first couple runs. Seating the rings might be good for 20 HP on a 14 to 1 motor. Proper A/F mix is critical, especially with that kind of compression. The small primary tubes on the headers could be holding you back. A lot of seemingly minor things can combine to cost you a lot of power. A 14 to 1 motor will be finicky to tune properly and may take 15 or 20 runs or more to dial everything in just right with a real good tuner. Good luck!
I will be track tuning to 12.8 : 1 A/F ratio (without spray) and will also use hotter plugs. The larger primaries on my exhaust should give me another 10 - 15 HP.. I think that I could get to about 640 HP if tuned properly (maybe 650) BUT it's still far away from the targeted 700 HP..
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Wow, can't believe you actually got some realy dyno numbers. It's all in the tuning from here on in, you will pick up some more HP easy.
That motor should be pulling to 7000RPM and beyond, meaning the HP should be increasing, not allot, only a few ponies but the fact that it is dropping after 6400RPM leaves me to believe the heads aren't flowing enough for that big 434ci. Anyway congrats still a killer motor
That motor should be pulling to 7000RPM and beyond, meaning the HP should be increasing, not allot, only a few ponies but the fact that it is dropping after 6400RPM leaves me to believe the heads aren't flowing enough for that big 434ci. Anyway congrats still a killer motor
Thread Starter
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
I just checked and the Powerglide indeed mounts 6 inches from a TH400 mount.. Didn't know about that.....
Last edited by GrandSportC3; Jul 29, 2007 at 12:03 PM.
Thread Starter
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Joined: Jul 2001
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17