Looking for some advice!

Everything from the motor to the wheels

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496StrokerOlds
Posts: 34
Joined: Thu Nov 01, 2007 12:43 pm
Location: Enon Valley, Pennsylvania

Looking for some advice!

#1 Post by 496StrokerOlds » Fri Aug 29, 2008 11:01 pm

Hey everyone! I'm looking for some advice on what to do with my current combo. I have been to the track with it a few times and the times havent been what I thought they would be. I was able to take it to a chassis dyno to get the car dialed in with timing, setting the carb up and knowing what the numbers of the motor were. The car made 400 rear wheel horse and 538 rear wheel torque. So far the best ET that I have been able to turn has been 11.70 @ 114mph. I have a buddy that also went to the dyno with me and he only made a few more horse and a few more torque than I did and he's able to run much much faster than me so I was a little puzzled what could be wrong in my case.

My current combo is:

1976 Pontiac Ventura
496 Olds:
4.185 bore
4.5 stroke
6.800 eagle rods
455 crank thats been offset ground and fitted to rods
BRC pistons..9.75:1 actual compression
MSD Distributor
Summit digital ignition box
Rocket racing Heads
Rocket racing intake
Comp cams Extreme energy 284 cam
duration at .050 Intake 240 exhaust 246
Lift at .050 intake 541 exhaust 544
Harland Sharp 1.7 ratio rockers
BIGS 950 carb with 1" 4-hole spacer
77 jets in front..81 jets in rear and the A/F was dead on
1 3/4" headers with 3" collectors
3" exhaust into X-pipe into 3" spintechs mufflers at the rearend
TH-350 tranny with manual valve body
3600-3800 stall converter (stalls more like 3200 tho!)
9" ford with 3.89 gears and a spool
29.5x10.5x15 Hoosier slicks (approx 30" tall)

Front suspension is nice and loose and has good travel.
Rear suspension is new with mono leaf springs from Calvert Racing, cal-trac bars, and Afco double adjustable shocks.

Went to the track tonight and tried shifting at different RPM's and when I shifted first and second at 5400, i went through the traps at 5000 rpm. I then tried shifting a little higher at 5600 and went through the traps at 5200, but the MPH and ET did not change at all.

I'm to the point where I think the converter is too tight so I have one that is going to be sent out to have re-done and I also thought about maybe doing a rear gear swap for something that will really get this thing out of the hole and down the track. Along with a gear swap the option of a new cam has been brought up and only seems like a good idea.

A good buddy has a cam with the specs of:
duration at .050 intake 266 exhaust 270
lift at .050 intake 584 exhaust 560

Even though the cam has a pretty nasty profile, I would be at the point to entertain something like that and match my converter and gears to it with the size tire I have since they are like brand new.

So with all that being said what does everyone think would be a good route to take with choosing a cam and rear-gear setup? The car is rarely driven on the street anymore so street manners can be thrown out the door as I want this thing to really rip down the track with the big cubes it has.

Thanks in advance....looking forward to some good input!! :D

mytmouz
Posts: 647
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Location: Pelahatchie,MS

Re: Looking for some advice!

#2 Post by mytmouz » Sat Aug 30, 2008 12:06 am

Seems like you need more gear with that tall of a tire. The convertor should be ok with the cam you have now. Although with the 1.7 rockers your cam is probably a bit bigger than the specs, so it could need a bigger one. How does the car seem to go now? Does it seem sluggish out of the hole and then pick up, does it seem to leave good then nose over, or does it just seem to be underpowered overall for the combo? THis will help the bench racers to gather their thoughts...
Trucks are for haulin...

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wikd69
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Re: Looking for some advice!

#3 Post by wikd69 » Sat Aug 30, 2008 12:45 am

One comment I'll make, and a follow-on question for the group:

Given that this is a 496 big block with lots of cubes and lots of flow, are your 1 3/4" header primaries big enough ? I don't know, but it seems like you'd want bigger primary tubes for that displacement, especially running aftermarket heads. I've aways thought bigger was better in header tubes, especially for big blocks. Of course, it wasn't until last year that I learned that there really is no such thing as a prune tree <laffin>

Nice motor build, btw :)

For the group: Do these smaller primaries help produce the torque this motor is making ? I really don't know the science behind this. Heck, I have 2 1/8 primaries on my 427, though I do have the huffer. If someone knows, please enlighten me as to what the gains are running smaller primaries.
1969 ProStreet Camaro RS Best 9.75@139 1.46 60'
Blown 427 BBC, TH400 w/Brake, Back-Half Ladderbar
Narrowed 12-Bolt, 4.10 Gears, Spool, Moser 33 Spline

http://www.marsh-racing.com/harrys_camaro-1.htm

496StrokerOlds
Posts: 34
Joined: Thu Nov 01, 2007 12:43 pm
Location: Enon Valley, Pennsylvania

Re: Looking for some advice!

#4 Post by 496StrokerOlds » Sat Aug 30, 2008 9:11 am

Hey guys! Thanks for the responses so far.

mytmouz--to start answering your questions it just seems the car is sluggish all over. I thought I would be expecting this thing to really set me back in the seat right off the line, but it doesnt seem to be that way. I mean it does throw you back a little, but nothing like it should being that big of a cubic inch motor. I know going to more gear should help out with that and I'm hoping with a better converter that will also aide in helping matters for sure.

wikd69--I have wondered the same thing you have mentioned before and at the time when I bought the headers they were the only ones I could find because of the model car I have and the motor combo that is in it. I have seem a set tho that has 1 7/8" primaries with I believe 3 1/2" collectors so I dont know if those would help or if those still arent big enough.

The cam I mentioned that my buddy has.....would that be something to maybe think about throwing in with a new set of gears and the converter that will be on the way soon??? The cam and lifters are there to use if I want them and my setup can accomonadate it so it was just an option as I thought that could really wake things up.

60ft times from the track last was a 1.738 and 1.735. I also forgot to mention in the original post of the fuel system. It starts with a fuel cell plumbed with -10 line into an aeromotive a1000 pump then up to the engine compartment into an aeromotive a1000 regulator that then has 2 -06 lines coming off it and each line feeds a carb bowl and the regulator has a -08 return line.

Thanks again....looking for more great advice!!

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supernova
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Re: Looking for some advice!

#5 Post by supernova » Sat Aug 30, 2008 11:33 am

More gear ( 4.30 ), nitrous ( 150 shot ):mrgreen: The tires can take a lot more!

Leave the converter alone you will need it with more gear.

Whats up with the headers?

The rest of your combo sounds ok for now.
Blackhoodmafia!!!! :mrgreen: :mrgreen:

1972 Nova SS
572 C.I. BBC

Best to date: 1/8
et: 5.28
mph: 134
new wt. 3340 lbs

496StrokerOlds
Posts: 34
Joined: Thu Nov 01, 2007 12:43 pm
Location: Enon Valley, Pennsylvania

Re: Looking for some advice!

#6 Post by 496StrokerOlds » Sat Aug 30, 2008 11:55 am

supernova--thanks for the response. The idea of a 4.30 gear was something for sure that I might have to lean towards. My buddy and I are going to pull the motor soon to replace the pan gasket and we have been thinking about a cam swap so that's why I wanted to get everything ironed out now so we have a game plan before we do anything. The cam that I mentioned on here calls for pretty much everything I have now except the compression that the cam asks for is 10.5 where I'm at 9.75, but the carb and intake is good for it and then if I went with that cam I would have to go rear gears in the range of 4.10-4.56 so you mentioning 4.30 would be good I think.

With the cam mentioned, different rear gears, and a better matched converter would that really wake this thing up??

Also if anyone knows anyone that might have different headers I would love to know because these seem hard to find with the chassis I have and the motor that is in there.

Thanks in advance!

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supernova
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Location: Ft.Worth Tx

Re: Looking for some advice!

#7 Post by supernova » Sat Aug 30, 2008 1:01 pm

How thick of a head gasket do you have? You could use a thinner gasket to raise the compression.

I'm using a .030 thick gasket instead of a .045, or .060.

What about the bore of the gasket? It might could be smaller too.

Anything to raise the compression while your motor is out of the car.

Just some things to think about.
Blackhoodmafia!!!! :mrgreen: :mrgreen:

1972 Nova SS
572 C.I. BBC

Best to date: 1/8
et: 5.28
mph: 134
new wt. 3340 lbs

496StrokerOlds
Posts: 34
Joined: Thu Nov 01, 2007 12:43 pm
Location: Enon Valley, Pennsylvania

Re: Looking for some advice!

#8 Post by 496StrokerOlds » Sat Aug 30, 2008 1:13 pm

I think there is a .042" head gasket on the car right now. I would have to dig my sheets up to double check on that one for sure though. I have thought about a thinner gasket to bump up the compression ratio also and since the motor will be out soon it would be an easy time to do that for sure. I would just have to double check everything to make sure all would be ok going to a thinner one.

Thanks again!

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stroker1
Posts: 333
Joined: Tue Apr 03, 2007 1:14 pm
Location: Dunn, NC

Re: Looking for some advice!

#9 Post by stroker1 » Sun Aug 31, 2008 10:21 am

Angle mill!!! Shave the heads!!! Thinner gasket!!! :lol:
'87 S10 stock suspension, Caltracs, 9" rearend, 1.82 Glide, 383 SBC,
Brodix Track1 Heads, 14:1 compression, 180 shot plate,
2" tube Hussler Headers, 1.38 60ft., 6.20 ET 1/8th, 109 MPH,
Still Tuning, more to come.

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Bob West
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Joined: Sat Dec 24, 2005 1:39 pm
Location: Republic,Mo

Re: Looking for some advice!

#10 Post by Bob West » Sun Aug 31, 2008 2:54 pm

I picked up .10-.15 going from 1.75 to 2" tubes on my 505. I would think the Olds would make enough torque to pull those gears and they dont like to be wound up too tight. I would look at a tight 8" converter too.
72 Malibu-Nov. '08-1.329-3.995-6.280@106.94-9.988@131.62
best 60ft to date- 1.319
http://www.dragtimes.com/1972-Chevrolet ... -5251.html

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wikd69
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Re: Looking for some advice!

#11 Post by wikd69 » Sun Aug 31, 2008 4:09 pm

stroker1 wrote:Angle mill!!! Shave the heads!!! Thinner gasket!!! :lol:
Yeah, what stroker1 said !!! :D
1969 ProStreet Camaro RS Best 9.75@139 1.46 60'
Blown 427 BBC, TH400 w/Brake, Back-Half Ladderbar
Narrowed 12-Bolt, 4.10 Gears, Spool, Moser 33 Spline

http://www.marsh-racing.com/harrys_camaro-1.htm

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BILTIT
Posts: 187
Joined: Tue Aug 07, 2007 11:14 am
Location: Lloydminster,SK, CANADA

Re: Looking for some advice!

#12 Post by BILTIT » Sun Aug 31, 2008 4:40 pm

496- we are in a similar boat.

My setup is very close to yours, alittle more cam and less cubes here though.

My convertor is holding me back (3200). I run 28'' tires and cross at 5500.

11.97/111/1.65 last year (dual plane intake, smaller cam) crossing at 5200, this year i ran 12.0/112/1.77 crossing at 5500 with a single plane intake and larger cam lashed way too tight.

I will post the rest of my specs later tonight as i am at work right now.
1974 Pontiac Ventura, 455P (9.5:1 comp.), 850DP, 3100 ''Tight'' 10'', 3.73's/28x13.5
Upgrading in June:
KRE 310cfm@.550 heads, 10.5 comp., hyd roller, 3800 tight 10'', better rear suspension.
Race Weight: 3750#'s
2007 best: 11.97 at 110 1.65 60ft.

sc racing
Posts: 1773
Joined: Sun Jun 11, 2006 1:45 pm
Location: Sahuartia Az

Re: Looking for some advice!

#13 Post by sc racing » Sun Aug 31, 2008 8:21 pm

496- you never posted how much your car weighs.

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BILTIT
Posts: 187
Joined: Tue Aug 07, 2007 11:14 am
Location: Lloydminster,SK, CANADA

Re: Looking for some advice!

#14 Post by BILTIT » Sun Aug 31, 2008 11:34 pm

Pv's plugged or not in the carb? Jet seems alittle on the small side for a 950, my modded 850 has 80/88 with PV plugged in rear. I dont know anything about your heads but i assume they are equal or better to mine (factory D-ports ported to 260cfm) so i figure you ahould be running more fuel than me.
1974 Pontiac Ventura, 455P (9.5:1 comp.), 850DP, 3100 ''Tight'' 10'', 3.73's/28x13.5
Upgrading in June:
KRE 310cfm@.550 heads, 10.5 comp., hyd roller, 3800 tight 10'', better rear suspension.
Race Weight: 3750#'s
2007 best: 11.97 at 110 1.65 60ft.

496StrokerOlds
Posts: 34
Joined: Thu Nov 01, 2007 12:43 pm
Location: Enon Valley, Pennsylvania

Re: Looking for some advice!

#15 Post by 496StrokerOlds » Mon Sep 01, 2008 10:10 am

sc racing--the car weighs right around 3600 with me in it I think.

biltit--the carb has a power valve in the front...4.5. In the rear is doesn't have one. We started with jets that were higher in number but it was lean and really through the A/F ratio off. Where we have the jets now got the A/F ratio down in the 12.2-12.4 range throughout. I think the flow numbers on the heads are real close to 320 intake side and 285 exhaust side. That is just off memory, but I think thats right on the nose of what they are suppose to be as listed on the website.

Thanks again.

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