Orig69
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Not sure if you tried the Brawler 850
New 440 build issues
- Thread starter chermik1999
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PRHeads
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Sounds like a trip to the chassis dyno might be a good idea.
Get the fuel and timing situations sorted out.
Get the fuel and timing situations sorted out.
Thats going on next.
Ya maybe so. But where I am now with all I'm reading might be time to change cams..lol
Wietse
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Or, change the rear gearing for a 3.73 or higher.
GTX MATT
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I would guess they do not do many performance engines, so I would be suspicious of anything they did. They probably didn’t degree the cam. That said, it helps to have it right and verify, but a few degrees isn’t going to totally turn it into something else. 160 with a mini starter is a little low, but not out of line at 9.5:1. The actual CR may be closer to 9:1 or maybe even a touch less. But its unlikely that the timing chain is off a tooth, or that there is a mechanical problem with rings or valves with that reading.
All that said, a healthy short block, even at 8.5:1, with a 509 cam should run HARD as long as it has the induction and exhaust to match. Yes you could use more gear, but you have enough converter.
Your exhaust sounds restrictive with resonators AND turbo mufflers. Turbo mufflers work well on stock engines, but can be very restrictive on engines that have a good bit of cam in them and need good scavenging. Especially if you have smaller pipes. Hush Thrush Turbos will suck power out of a 500 HP engine like you would not believe, and still be loud.
Does it pull hard when it gets rolling? And does it run harder when its cold?
Try the other carb and verify the AFR. You need to fix that first. You need to be 12-13:1 at WOT. If you’re running pump fuel with a mechanical pump it may be vapor locking.
A 30 GPH electric pump doesn’t sound adequate though.
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Well not much I could do. Couldn't hear myself think..lol. remember it's a lil red. Not much pipe to the stacks.
Pulls ok but seems held back even rolling.
Cam easier..lol. but have 3:55 to install. Can probably exchange for 3:91's
I could put the borlas back on. Just loud...
Actually I'll run open for a few runs to try it.
GTX MATT
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Just don’t run the headers open with no extension. That puts a big hole in the torque curve too, run 18+ inches of pipe after the collectors.
Try the other carb first though before you go through the hassle, and make sure you’re in the 12s or 13s for WOT AFR.
K...was going to leave collector's to resonators on so I could still use the AFR. Like 24" to turbos...,kk
Geoff 2
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Chermik,
You are missing the CLUES.
5-6" of vacuum is too low, & indicates a problem. A different carb cannot fix that. Maybe the cam has been installed retarded. It is a very poor cam choice for this combo. This cam shifts hp from the low range to high range. In my opinion, Chrys did it's fans a big DISSERVICE with the descriptions of their performance cams. Not enough emphasis on the characteristics, rpm range, down side. You would be much better off with a Comp 270H Magnum cam or Isky 270 Mega [ better]. You can only fix a bad cam choice....by changing the cam.....not by tuning.
A 30 gph fuel pump is too small. If the engine makes 450 hp [ I am being generous ], it will consume 45 gph, & you need a 20-50% safety margin.. You need a Carter 4594 elec pump, 72 gph.
A very wise cam grinder, Sig Erson, decades ago recognised the shortcoming of the high rod/stroke ratio of the 440. The 440 has the highest r/s ratio of all the popular BB engines, only beaten by the 350/361/383/400 which were slugs. The duration warning [ below ] only appears for the 440, no other engine.
You are missing the CLUES.
5-6" of vacuum is too low, & indicates a problem. A different carb cannot fix that. Maybe the cam has been installed retarded. It is a very poor cam choice for this combo. This cam shifts hp from the low range to high range. In my opinion, Chrys did it's fans a big DISSERVICE with the descriptions of their performance cams. Not enough emphasis on the characteristics, rpm range, down side. You would be much better off with a Comp 270H Magnum cam or Isky 270 Mega [ better]. You can only fix a bad cam choice....by changing the cam.....not by tuning.
A 30 gph fuel pump is too small. If the engine makes 450 hp [ I am being generous ], it will consume 45 gph, & you need a 20-50% safety margin.. You need a Carter 4594 elec pump, 72 gph.
A very wise cam grinder, Sig Erson, decades ago recognised the shortcoming of the high rod/stroke ratio of the 440. The 440 has the highest r/s ratio of all the popular BB engines, only beaten by the 350/361/383/400 which were slugs. The duration warning [ below ] only appears for the 440, no other engine.
Very good point. Vacuum of 5-6 Hg is pretty low. My 427 Corvette has an old mechanical cam of 256/266 degrees, .579/.600 lift and even it manages 8”. The .509 lift purple cam is rated at 248 duration so I would think it should pull at least 8 or 9” vacuum, maybe a bit more. Since your idle AFR is not bad something else is pulling down the vacuum.
When I was a kid I put a Crowler 280 cam in my stock 383 1964 Sport Fury (3.23/TF) which was widely advertised around 1970 as the cam to get to perk up your stock Mopar. It killed the low end of the 383 which had been its strongest attribute. I have to agree with Geoff 2 that more cam is not necessarily better on these engines.
When I was a kid I put a Crowler 280 cam in my stock 383 1964 Sport Fury (3.23/TF) which was widely advertised around 1970 as the cam to get to perk up your stock Mopar. It killed the low end of the 383 which had been its strongest attribute. I have to agree with Geoff 2 that more cam is not necessarily better on these engines.
B-mine
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New fuel pump, is it electric? Had this problem, gradually wouldn't run after awhile, would just run the fuel in the bowels, till fuel pump filled them up again, all new parts, was the filter in the tank to a almost closed off position on the pick up tube, which found out that the filter is made to close off completely if pushed down far enough. I started at the other end replacing parts, and checking, finally pulled the the tank, thought nothing until I saw the filter on the tube. Pulled the filter, spot welded some spots, put it back on , never a problem after that.
Wow! Never had it explained to me like that before. Thank you...so cam change then..
All been replaced so have that covered. Thanks.
I'll do a detailed check for leaks...maybe there is.
cudatom
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We ran this cam extensively in the early 80's. A couple things we found
1) with 906 heads it liked timing. We ran at 38 for best results. You are there.
2)it likes rpm, meaning it was an absolute dog until about 4200.
We tried 3500 as DC suggested but found 4500 was best and 410 gears.
3) we had the best luck running electric fuel pumps. Tried every aftermarket mechanical pump and none would keep up.
4) we always ran Holley. The 750 dp worked great on the street and track. Took lots of playing to get right.
We ran this cam well into the 11's
Thanks. They are actually 516's. But I kinda figured as much. It's a track engine. As most have mentioned, 3500 or more stall and at least 3.91 or more. Still puzzled about the 5-6 hg, but I'll search again for leaks.
In any event this wasn't really what I was looking for in a street car.
I think cam change and adjustable rockers as well.
So with what I have now gearing, stall etc what would ya'll recommend?
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