ronmiller

My thoughts and past experience comparing your combo to what I put together back in the mid 80's. You have a Good combo of engine parts. I Personally do not think the Big dome or intake is hurting you at all. What I do know is you got to gear a 427 like a small block. Especially when using a PG. I also think you need more stall/flash from your converter. Something around 5700 to 6200 stall/flash. I would have a minimum of a 5:14 rear gear. I my self would have a 5:38 or a 5:57 in the rear. Then make the 4 link work for your cars 60 footer. I would be shifting that Bad Dude more closer to 7600 to 7800 r.p.m.s. I think your car is capable of mid to low 9's with a gear & converter change. Another thought, when is the last time you had your converter checked ??

The combo I put together back in the mid 80's had a old Edelbrock V Jr. The one that had the twisted/angled carb & a modified 850 on it. A Crower solid lifter cam (not a roller), 188 iron ported heads w/ 2.250 intake valves, 13.1 compression, 6.135 7/16's rods, GM 427 crank. A Good Basic 427 build. The car is a SG style ladder bar a-arm car, weight was 2500 l.b.s. race ready. This chassis by no means was up to par. The first night out with the car, it ran 10:00's @ 137 m.p.h. I couldn't run any faster because I did not have the SG licenses. Later in the year with another guy driving the car, it ran some 9:80's with no other changes. The next year we maid a head & cam change. The car picked up a bunch ever where. The e.t was down in the low 9:00's and m.p.h went up to 143. The guy that owned the car was a Bull head. The chassis & springs were set up for a Military truck. I felt with the correct changes, that car was capable of running 8:50's easy.

One last thing, the 427's do not get the respect it deserves. People refuse to believe they just got beat by a small engine. ops:


Ron 92Camaro

travis91

Maxpower and cp, everything listed has been after the rebuild. The car was running 1.45-1.47 60 ft times with the old carb. I went up/down/sideways on the jetting trying to get it to improve and that was the best it would do. I changed fuel pressure and float level and played with timing from 34 to 41. The old motor liked 41 but the new motor likes 38. I have only made 5 passes with the new carb and jetting was set to 84/92 by Patrick at PS. It ran a tenth faster at same mph than the 800 with that. The a/f gauges were reading rich so I went to 82/90 last time after consulting with Patrick and it picked up another tenth and 2 mph. It is still just a little rich so next time out it will have 80/90 jets. I have not played with timing since the new carb but that is on my list next. The glide is 1.76 as far as I know. It was in the car when I bought it last year.

Ron, I know that 427's are supposed to like high rpm but with the old motor it ran the fastest shifting at 6700. Which is about what the chassis dyno showed because it was dropping off quickly after 6700. By 7000 it showed a loss of 50hp. The torque curve from 4900 to 6200 was with 10 ft lbs. Now I don't know how much changed on the torque curve from the old motor and the new since the cam is the same and the car runs the same times that it ran previously. I am sure there is a couple more tenths in the car with tuning with the new carb but what doesn't make since to me is that everything being equal before the carb change. Why didn't the 3 pts of compression seem to make any difference in my et's. The car hooks good and doesn't blow off the tires. It lifts the left wheel about a foot and the right wheel about 6 inches on launch.

Thanks for all the information guys. I know there is something wrong with the combo somewhere I am just trying to narrow it down before I spend another 5 grand swapping out parts if you know what I mean.

zipper06

I'm thinking that a change of the manifold, as mentioned in 2 above post, maybe a 454R and put a 1" spacer under the carb. That should give it a little more wind. Not many people i know runs the team G except on the street.

JMO

Zip.

maxpower671

good advice and info everyone 8)

doesn't the data and the dyno show the mismatch between heads and camshaft and gearing... :?:

whenever the heads are too big or the cam too small and the RPM to operate in proper range is not present, most likely you will be dissappointed :cry: ... some things you can bandaid, but when talking cylinder heads and camshaft, gearing, not really possible.. .02cents

supergass

I agree with Ronmiller, I think you need more converter more than anything, but it will probably like a bigger cam to go with it......especially in the duration. I like everything else on the cam where it is. With a BBC with square ports and small inches it really needs a minimum of 5500 stall. The victor jr is what I prefer to. If you do put in a bigger stall speed converter a dominator will probably add a tenth or two as well.

travis91

I will try a new billet roller cam and possibly a new intake over the winter shutdown. Who should I talk to to get the best cam profile for my combo. I just checked the converter since I hadn't done that since the rebuild. Before the rebuild last year it was hitting 4500 stall and now it is only hitting 3900. I have made probably 50 passes since I checked the stall previsously. Now I have 2 questions. One, did the stall of the converter change because of the added compression of the engine or is it just from use. Secondly, even though I didn't change the cam would the added compression move the torque and horsepower curve of the motor and if so, would it move the curve up or down?

travis91

So far the best run on the car was 9.87 at 136 in cold air. But consistanly running 10.0's in 70-80 degree air. I decided to replace the cam and I emailed several cam builders with my combo and based on several recommendations ended up going with a Lunati grind with 110 Lobe seperation, 272/280 duration and .722/.722 lift. Installed cam at 107. Ran it for first time today and at 35 degrees ignition advance it was breaking up badly above 6000. Removed 3 degrees and it improved. Removed another 2 degrees for a total of 30 degrees to clear it up. The best run was 10.11. Checked the torque converter and verified it is stalling at 4000 and I will be replacing it after tuning in the new cam and putting it on the dyno to get its new torque curve to build the new converter. I am a little confused as to why 20 degrees more duration would require 8 degrees less advance. Anyone have any thoughts on what might be the issue?

bones427

I ran a 427 .03 over 12.5 comp canfield 310 heads cam 671/690 248/254 dur 106.5 cl victor 454r 4500 intake i had a 850 on it and went to a 1050 it picked up 3 tenths car weighed 2600lbs with a 4.56 gear 32 tall tire it ran 9.70s went to a 4.88 it went 9.50s it really liked the steeper gears this was also with a turbo 350 and 5000 stall. Just thought this might help.

cepx111

I know your starting to dig a money pit here changing parts in all, but I'm gonna say your combo definetly warrants a 1050 dominator, converter change ( 8 incher, 5000 min, preferably 5500 stall) plus a intake change AND to further compliment the combo, more gearing(513)

Clueless as to why you'd need less timing with that cam though.
That dont make any sense to me? 30 TT :shock: I've never seen a BBC run with that low a timing, not worth a shiznit anyway.
Our combos are very similar, save for the smaller CI and the carb.

I run the same cam in my 496, (excellent choice by the way), I run TT @ 40 to 41, never misses a beat.
What plugs are you running? And what gap? I have merlin vr 345cc heads on my motor and use the NGK's racing plug in the #8 heat range gapped @ .032
I can get the offical part # if you like, just let me know.
Cp

Tod74

Are you sure you are only running 30 deg of total adv? Did you locate TDC with a degree wheel? Is this a stock balancer that could have slipped? Hard to understand why it would want 30 deg of timing.