VIN 3307 Drag Race Videos/In-Car/Warm Idle/DMC CA Cams-Result:Stock Peformance-Help!

[DeloreanJoshQ]

Tonight I decided the time was right to take VIN 3307 to the track to see the performance increases over the stock engine set-up.

Let me first set you up on the background....

I have drag raced casually for over 12 years, not professionally, but I know my way around the track, tree, and driving techniques comfortably....

I did not get to drive or test my car before the performance upgrades to have a comparison...The car runs great; no hesitation, smooth acceleration, etc. However, I don't have a stock car to drive and compare to.....

Below are the parts that differ from stock:

DMC-CA Performance Camshafts (advertised +62HP)
http://www.dmccal.com/102707hp_high_...ance_cams.html
Ported and Polished Heads,Valve Job (HP increase unknown)
Cat Converter Delete Pipe (HP increase unknown)
K&N Filter/Hervey Cold Air Intake (HP increase unknown)
Taylor 8mm Wires, Pertronix Coil (HP increase unknown)

There is only one major variable which has been brought up: The exhaust. I have stock manifolds, cross-over pipe, no cat, and stock muffler. More on this later...

Before I went to the track I researched what a stock Delorean would do in the quarter-mile.I went to Tamir's site and found the following sources to give me a good estimate:
I didn't want to trust one source for fear of manipulation of the magazine writers...but they all showed results in the 17-17.9 second/76.5-79mph range....

Road and Track - Dec '81
http://www.entermyworld.com/cat/arti...tdec81e1x1.jpg
17.9 seconds/76.5 mph

Car and Driver - Dec '81
http://www.entermyworld.com/cat/arti...ddec81f1x1.jpg
17.0 sec/79 mph

Motor Trend Dec '81
http://www.entermyworld.com/cat/arti...tdec81e1x1.jpg
17.61sec/77.4 mph

Motor Trend April '82
http://www.entermyworld.com/cat/arti...tapr82g1x1.jpg
17.45 secons/77.7 mph

Alright, so now I have something to compare to...so here we go...

First run, in-car camera(wife)
http://www.youtube.com/user/joshjegs.../3/EYSH1QHELMA
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Shifted at around 6000 rpms, stayed in 3rd gear
Second run...
http://www.youtube.com/user/joshjegs.../2/ymO2iX6Hrbs
[email protected]
Shifted at 5500 rpms, stayed in 3rd gear
Third and final run..
http://www.youtube.com/user/joshjegs.../1/U0tX6N6yJ-w
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Shifted at 6000 rpms, stayed in 3rd gear
At this point I decided my driving skill would not improve the cars performance significantly any further....

So now I am frustrated because I am lining up with stock performance after all of the hard work(ex. 2nd run nearly identical to Road and Track results)to improve it and now I want to figure out why my car is peforming exactly like a stock Delorean....

The camshafts were supposed to add the most HP to my car, so they are the first to research and rule out in a few ways....

-Below is a video of the idle of my car:
http://www.youtube.com/user/joshjegs.../0/QGYuTaLD060

Can anyone confirm by audio comparison if the idle matches that of the idle of a car with the DMC CA camshafts?

Does anyone know the camshaft lift for the intake and exhaust for both stock and DMC CA camshafts? I would like to remove a valve cover and mic the intake and exhaust lobes to check lift...

I have close access to a performance shop with a Mustang dyno and can take the car there to check HP figures...but I am guessing they are going to align with stock engine specs based off of tonight's runs....

As I stated, the car starts up great cold, warm, or hot, idles nicely, no hesitation, smooth acceleration....just doesn't appear to have the performance that I believe it should with what was done....

I talked to Danny B at DMC CA, he said he had never heard of any issues with the cams and that everyone he had talked to were happy with the performance increase...he did not have the specs on the stock and peformance cams; I have to wait until Tues for Don to be available to get them...

Danny said that they always have the stage one exhaust on their cars with the camshafts and recommended it....I understand that the stock exhaust would decrease some of the HP potential...but it is hard for me to believe it would restrict nearly all of it...

Anyone have any other ideas or opinions on what parts and where to check?

I'd really appreciate it!

Josh Q

[sdg3205]

That's bizarre.

Are you allowed to pull of the headers and do a run?! That would tell you (and by how much) if the stock exhaust was holding you up.

[DeloreanJoshQ]

That's bizarre.

Are you allowed to pull of the headers and do a run?! That would tell you (and by how much) if the stock exhaust was holding you up.

That would be alot of work and I really don't think the stock exhaust (even if I put the cat back on) is capping all peformance increases.....

i really just want to find the answer.....

If anyone wants any specifics from the runs, I have the time slips...
60 foot times were all in the 2.7 range
1/8 mile- 11.407secs/64.11mph, 11.527secs/61.86mph, and 11.375secs/64.76mph respectively....

[DMCMW Dave]

We had a car in here that was a full stage 2 engine but with stock exhaust (there was a delay on the exhaust at the time and they wanted the car done). It was just about impossible to tell it from stock - maybe a slighly lumpier idle.

The OEM exhaust is so restrictive that the added flow from the head/cam work was negligable in terms of making power. Once we added the header part of the kit it all seems to wake right up.

Sorry, no dyno or drag strip testing on this one.

[DeloreanJoshQ]

Ugh...if this is true Dave, it's gonna be a while before I can save up 1500-2000 dollars to realize the 1000 dollars i just spent on the cam and head work.....

"welcome to Delorean ownership"?

[jmettee]

Josh,
The only different between out cars is that I have the Hervey cat-converter & you have a straight pipe....& you have stock muffler & I have a Flowmaster. I know my car woke up with changing the cams only, so there should be a difference. Also, my car dyno'd with 130HP at the wheels before the cams. If we believe the dyno, then I would tend to say that yes, the muffler is the primary restriction.

Like you, I put the cams in 'while I was in there', knowing that in the future, I will upgrade to headers. I still need to dyno my car, but may be a while as my work schedule has me on weekly travel at the current time.

IIRC, the specs I was given by Don were .190" lift on the stock cams & .275" on his. While possible, I would doubt DMC-CA mixed up cams. Before I pulled the valve covers, I'd pull the muffler & take a listen to the exhaust note out of your test pipe. The cammed idle should be obvious without the muffler if it is truely restricting that much power (it should sound VERY lopey without a muffler....like this http://www.youtube.com/watch?v=SRsK4qRRnSk)

Lastly, it's hard to hear from the video, but what was your engine speed at launch? On my laptop, sounds like your incar video was just at idle. I know drag racving takes practice & launch is a key parameter & getting good times or bad times.

[jmettee]

Actually, just listened to the incar again....the engine note seems to sound like the performance cams. I recognize the same sound my car has & the stock engine doesn't sound quite as aggressive...there's a bit more of a gurgle/burble in it compared to stock. But again, somewhat hard to hear on a computer.

[mluder]

I'm certainly no expert on this sort of thing but I recall reading somewhere that with the stock engine, cams, etc. JUST by changing over to a high flow muffler you can add 50 hp.

Steve
#4456

[mluder]

Just watched the idle video... Does your oil preasure always run so low at idle? Mine almost pegs at idle and just bounces around up at the top. Of course, under accelleration its topped out.

[sdg3205]

Here's my question:

If you can buy the cams for $600 and get 60 HP gain, bringing the car to 190 bhp and throw on a stage 1 exhaust set up for roughly $2,000 and maybe get another 10 ponies out of that, why spent 5k - 7k on "Stage II" at all? Sounds like you get pretty much the same HP for half the cost.

Anyone?