what's wrong with this combo

Posted By: metcoll

what's wrong with this combo - 09/25/09 08:20 PM

friend of mine has a 3900 b-body 030 440 isky 280 cam six pack pistons eddy torker intake 750 dbl. pump headers 13/4 3-angle valve job msd ignition 2500 stall converter 4.10 gears...could only muster a best of 13.60 @98 mph...we were expecting high 12's timing seemed ok...seems that this would be a decent combo, do guys see something out of the ordinary...thx

Posted By: rebel

Re: what's wrong with this combo - 09/25/09 08:26 PM

whats the c.r?

Posted By: Triple Threat

Re: what's wrong with this combo - 09/25/09 08:34 PM

Is it getting full throttle?

Posted By: gch

Re: what's wrong with this combo - 09/25/09 08:38 PM

What does "timing seemed okay" mean?Where was the timing set at?
Not the best intake but should work with the gears.
Not sure on the cam specs but seems like the motor is down on power with that mph.

Posted By: cgall

Re: what's wrong with this combo - 09/25/09 10:27 PM

What was 60-ft. time, did he spin a lot?

What did he shift at, I would shift that combo at 5500.

Any bog off the line or missing at the top of each gear?

Posted By: metcoll

Re: what's wrong with this combo - 09/25/09 11:35 PM

the 60ft was 1.8 i believe comp is approx.9.5....

Posted By: forphorty

Re: what's wrong with this combo - 09/25/09 11:47 PM

From the parts listed, i assume that it is a street car. What exhaust system?

Posted By: metcoll

Re: what's wrong with this combo - 09/26/09 12:32 AM

when we ran the car we had open headres & slicks

Posted By: Quicktree

Re: what's wrong with this combo - 09/26/09 01:15 AM

biggest problem I see is no converter to get that thing moving.

Posted By: Pacnorthcuda

Re: what's wrong with this combo - 09/26/09 01:19 AM

Quote:

biggest problem I see is no converter to get that thing moving.

With 4.10 gears his 2500 converter should be fine. The 1.8 60 foot bears this out (3900lb car),
With that 60 a VERY low 13 or more likely a high 12 should be possible if the top end is doing its job. He's not making the HP

Posted By: MR_P_BODY

Re: what's wrong with this combo - 09/26/09 01:25 AM

With a 1.8 60 and its weight its doing ok off the line,
I'm thinking it might be a fuel issue

Posted By: 506RR

Re: what's wrong with this combo - 09/26/09 02:40 AM

Quote:

What did he shift at, I would shift that combo at 5500.

I agree. I bet that combo noses over if you try to shift above 5500.

With a 1.8 60', it should be capable of running high 12's. Does it pull hard all the way through the traps? Do you have a fuel pressure gauge to see if it is falling off?

Posted By: metcoll

Re: what's wrong with this combo - 09/26/09 12:03 PM

we have a half inch fuel line from tank to motor with a holley electric pump...before the season is over we are going to pump a lunati 240/250 520/547 cam that i have sitting around, my 4.56 gears & 4200 stall converter,only guessing do you think this would improve the et dramatically thx...

Posted By: MR_P_BODY

Re: what's wrong with this combo - 09/26/09 12:17 PM

What size is the pick up in the tank and have you done
a gals per minute flow test

Posted By: 440Jim

Re: what's wrong with this combo - 09/26/09 12:54 PM

Quote:

before the season is over we are going to pump a lunati 240/250 520/547 cam that i have sitting around, my 4.56 gears & 4200 stall converter,only guessing do you think this would improve the et dramatically thx...

As it is now with a heavy car, stockish heads, low CR (9.5), low stall speed; that is about what you will get. Perhaps a tad better with tuning.

The 4200 will really wake it up, IMO. The proposed cam is about the biggest I would go at that CR, and I like Lunati, but I wouldn't be too quick to swap out the Isky. Keep the RPM below 6000 and it will be happier.

Posted By: Hemiroid

Re: what's wrong with this combo - 09/26/09 01:21 PM

Quote:

Quote:

before the season is over we are going to pump a lunati 240/250 520/547 cam that i have sitting around, my 4.56 gears & 4200 stall converter,only guessing do you think this would improve the et dramatically thx...

As it is now with a heavy car, stockish heads, low CR (9.5), low stall speed; that is about what you will get. Perhaps a tad better with tuning.

The 4200 will really wake it up, IMO. The proposed cam is about the biggest I would go at that CR, and I like Lunati, but I wouldn't be too quick to swap out the Isky. Keep the RPM below 6000 and it will be happier.

It runs about what it should, not "way" off, just average. I also agree that it will like the changes and pick up a bunch.