OneHellOfaDart

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AdamR

AdamR

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What RPM do you shift your 340 at ?
I was playing around with desk top Dyno and built a 340 with a set of ported RPM heads, 10.5:1 compression and the XE274 cam your using and got 462 horse at 6500 rpms wich means youd be shifting at close to 7000 rpms. Does it really pull that high ?

I used the Flow numbers from RyanJ. site.
 
:shock: Wow I have been shifting at 6200 rpm's. 7000 :drunken: If I remember when Mikel did it on his he said red line was at
6500? Though I have rev'ed as high as 6500 bumping off the 6al.
 
I was playing around with desk top Dyno and built a 340 with a set of ported RPM heads, 10.5:1 compression and the XE274 cam your using and got 462 horse at 6500 rpms
Click to expand...

Cool. That's almost the exact combo I am planning to build, 'cept I'll have another 20 cubes. :wink:

The problem reving that high, as I see it, is the hydraulic lifters. Unless you use the anti pump-up type, you are limited to about 6000rpm before they induce a valve float affect. I think the anti-pumps will get another 500-700rpm out of it.
 
Yeah its Im getting peak power at 6500rpm. You want to shift above your peak.
 

That cam is designed to make power in the 1800-6000 RPM range. It should drop off right about 6000.

I don't have the engine in my Desktop Dyno anymore, so I can go back to what I did for you.
 
Found the thread...

http://www.forabodiesonly.com/v-web...c.php?t=434&postdays=0&postorder=asc&start=15

Ok... Assuming the cam is installed straight up, and using stock Edelbrock flow numbers, you should be launching at 3000, shifting at 6300, running 12.34 @ 110 MPH.

That's just a quick run through Desktop Dyno/Drag. I can tune it a little later tonight to get more exact. DD says max HP is 381 @ 6000, tq is 377 @ 4500.
Click to expand...

I looked through the thread, I didn't see anything about the cam being an XE274, though. I think I created a generic cam with the same specs, which should have worked out to be the same...
 
Ive got all the specs for the XE274. I'll post them later. I also used Flow numbers for the heads that I got off of RyanJ.s site so they are fully ported.
 
LIFT-------AS-CAST---------PORTED
.100”-------72.5/N/A-----------75.9/N/A
.200”----131.1/107.0--------146.6/107.0
.300”----182.9/151.8--------207.7/156.0
.400”----216.6/181.2--------252.9/200.1
.450”----227.7/182.9--------269.1/207.7
.500”----235.9/185.6--------276.0/217.4
.550”----238.7/185.6--------285.0/221.5
.600”----242.2/185.6--------295.7/225.0
.650”----243.2/185.6--------300.2/226.7
.700”----243.2/185.6--------298.4/228.8

All #’s at 28” of water
No flow tube on exhaust port
2.02”/1.60” Edelbrock Stainless Steel Valves With Proprietary Intake Valve Back Cut Angle.
 
Heres the cam specs.


Cam type- Dual purpose street
Lifter Hyd.
Lobe center - 110
Cam spec @ seat to seat
Over lap - 60
intake lift @ valve .520 ( This is with 1.6 rockers) .488 for 1.5
Exhaust lift @ vavle .523 or .491 with 1.5
Int duration 274
exh duration 284
Timing adv. 0.0

IVO 31
IVC 63
EVO 77
EVC 29
ICA 106
ECA 114
 
I just ran it threw my Drag strip simulator. It says 415 horse with a best possable ET of 11.80 in a 3000lb car.
Actuall times ran were 12.80 with a 727, 3500 rpm conv 3.91 gears and a 28" tire.

By switching to a 4500 rpm converter and 4.57s times dropped to 12.03

Optimum stall was 4565 rpm and gearing is 4.75 with a 28" tire

switching to a A904 with a low 2.74 first gear dropped ET to 11.98 with a 4500 rpm conv and 4.57s.

Optimum shift points are 6555 rpms
it makes 1.22 horse power per cube
Optimim carb is 608-782 CFM
Opt, Primaty tube lenghth is 38.7 cubes
Shift MPH is 1st - 40.8
2nd - 73.6
3rd - 111.9 wich is odd since its a 3 spped so I dont know how youd shift from 3rd.
 
:scratch: man that stuff is cool i got to get me a game like that or what ever it is :thumleft: can u do that to my car?with all my parts
 
for the dyno program
intake
carb
cam
compression
head type, valve size and if they have been ported.

For the drag strip the same plus
car wieght
driver wieght
Conv. stall
Trans type
gearing
tire hieght
exhaust tube size
 
for the dyno program
intake - Eddy RPM
carb - Carter
cam - Adv. Duration: .260°/268°
Dur. @ .050'': 221°/228°
Lift: .430''/.450''
Centerline: 110°
Basic RPM: 1200-5200 RPM
compression - 8 something (Stock)
head type, valve size and if they have been ported.
stock Heads,Stock,not prted

For the drag strip the same plus
car wieght - 3350lb
driver wieght - 235lb
Conv. stall 3800
Trans type T904
gearing 4.56
tire hieght 27.5
exhaust tube size open for now,say 2.5 or 3" what ever u like
 
That was cool guys ! Now do you have a program for suspension ?
Stock leafs, Cal Trac's And qa-1 shocks ? Will Hoosier QTP 8" or 8"
M/T slicks stick it to the ground ? Or will I also need to relocate the springs and go with a wider tire? :D
 
My program lets you put in tire hieght and type. ie Slicks, streat/strip tires or radials. and then trction. Excellant,good, poor.
 
The shorter tire would improve ET abit now doudt. When I ran it trew before it wanted more gear anyway.
 
The computer doesnt simulate traction. Its something you have to pick. Let me see if I can find were I got the software so you can play with it too.
 
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