Ideas based on my first Dyno?

[Kaspar 21]

I have a '69 302 with a C4 transmission. Much is stock, but recently I had the Edelbrock Top End Kit 2091 installed, which basically is upgraded Intake, Cam and Cylinder heads.

Besides that I have a 650 CFM Edelbrock Carb, Tri-Y Headers, K&N filter and

recently changes the rear gearing from the standard to a 3.55:1 gearing.

 

So today I ran my first Dyno test and got 253 Bhp and 295 ft/lbs. (400Nm) torque. It's less than I thought it would be:-( According to Edelbrock the kit should deliver 367hp / 340 ft./lbs., but I was pretty far from that. I know their readings have a reputation of being unrealistic and the Dyno-guy didn't hit the 6500 rpm that the Edelbrock test did, 'cause he was a bit worried to go that high with the rpm. It seemed like the bhp peaked at 5000 rpms and so he didn't push it to 6500, like the Edelbrock test. But the torque peaked at 3800 rpm, which is the most interesting reading. Because it's a C4 transmission, he only drove it in 2nd gear. He seamed a bit unsecure of this, but if he ran it in D it would kick down at some point from 3rd to 2nd. It didn't kick down from 2nd to 1st. He seemed a bit unsure if this was the best way to run it.

 

Okay, so my question is this:

I had really hoped to get to above 300 hp and 320 ft./lbs. Is there a conversion from bhp to hp or is that the same?

 

What else could I do to get to there. I know it's a small block and I don't wanna spend much more money, just wanted to ask if you guys have a magic idea?

I'm probably gonna install some Magnaflow mufflers in the near future, but that's more because of the sound.

Had also thought of a Torque converter, but I'm not a mechanic myself, so every operation is costly. The reason why I got the Edelbrock kit is because it all fit together and I didn't have to pay overtime to my mechanic for mixing and adjusting different parts. Plus I live in Denmark so smaller brands are hard to come by.

 

Thanks for your time!

[Wycked69 20]

Was the dyno performed with the engine and transmission in the car ?

[Kaspar 21]

Oh year, the test was done with everything in the car. Which I guess Edelbrock's isn't, or?

[superduty69 11]

While you got lower than expected results, I see a few things.

 

One is that you are comparing engine dyno numbers to chassis dyno numbers. I'm sure Edelbrock's came from an ideal condition with no air cleaner and good long tube headers and sea level air conditions.

 

You also have to account for your drivetrain losses. It takes power to turn the trans and rear. 10-15% are the amounts usually suggested. Also by not running the car in drive could skew the results a bit as now you are not 1:1 in the trans and have more gear ratio. And this will not load the engine the same as in drive.

 

The dyno is just a tool. With no before numbers to compare the after numbers to....

 

Bottom line is are you happy with the power it now makes? If yes do the numbers matter?

[Kaspar 21]

Thanks for clarifying and I understand what you're saying, but numbers are easy to relate to and I got a bit surprised 'cause I was having Edelbrock's in mind. But the reading-difference totally makes sense.

Just wanted to make sure that I shouldn't go back and do some reading in different gears or at 6500 rpm, which seems quite high for the engine.

I got the dyno test, 'cause I did think it would deliver more power than it does, after upgrading to the top end kit.

[sportsroof69 13]

The car was in 2nd, and not it's 1:1 gear, so you can throw those numbers out the window. He should have disconnected the kickdown, and made the pulls in 3rd.

[MN69Grande 203]

One point I'd like to make. The 302 was only advertised at 210/215 HP originally and that was gross horsepower. Which as superduty69 talks about is ideal conditions with the motor out of the car. Your readings are net. I'd say you've added around 80 HP at the wheel and that is not a bad deal.

 

If you want more you're probably going to need different heads. If you put some Trickflow or GT40 heads on that sucker you'd easily be over 300, possibly better than Edelbrock numbers. But that isn't a cheap change. I think you've used all the cheap options up. You could get the stock heads reworked, but for the money I'd get new ones.

 

The torque converter will only make a difference on how the car launches. My guess is right now you have to stand on the brakes at a stop because the car is pulling pretty hard (I found this out from my own experiences). A new Torque converter can solve this problem.

[sportsroof69 13]

The heads in his top end kit are better than GT40s.

[RPM 1,190]

Oh year, the test was done with everything in the car. Which I guess Edelbrock's isn't, or?

 

Engine dynos don't use the transmission.

And yes, it should have been run in 3rd gear, I think. Never heard of them not being run in the 1-1 gear.

 

Bob

[Kaspar 21]

Thanks guys. I complained this morning and they admitted going in the 2nd gear was wrong, so they're giving me a new test next week.

[sportsroof69 13]

Good deal. It'll make more in high gear.

[MikeStang 247]

I'm guessing it will make 310hp and 325-350 on the torque when its done right.

Don't rely on those numbers too much tho...its the time slips that tell the true story...

I think your going to be pleased with what ya get when the dyno is done correctly

[RPM 1,190]

Back before I tore my engine and body into 10,000 pieces, the stock worn out M code rated at 290hp ran darn well. 300 hp is nothing to be ashamed of.

 

Bob

[69SlowResto 19]

I am going to have the same engine combo so I'm looking forward to your final numbers

[MN69Grande 203]

The heads in his top end kit are better than GT40s.

 

Sorry read the original post on my phone, didn't see the heads were part of the upgrade kit. I can see why you'd want to see more improvement than the first Dyno. Will be interesting to see what you get on the next run.

[THE EVIL TW1N 12]

I'm going to guess the car will make ~260 rwhp / 300 rwtq. Running in 3rd is the correct gear, but I dont think you will see a huge difference.

 

Obviously I don't know your complete combo since you havent completely listed it. 5.0's (87-93) running those heads through a T-5 would typically make about 280-290 rwhp, but that's through a more efficient transmission (~12% vs ~15-18%) and more efficient rear end (8.8 vs 9").

[Kaspar 21]

I'll be going back next thursday, but is there anything I should look for/ask for him to do, when he does the dyno?

Too bad the test-guy is quite a big fella, but I'll try to remove all other unnecessary weight ;-)

 

The Edelbrock chart said that their HP test peaked at 6500 rpm, but the dyne-guy didn't really dare to go that high. He stopped it at 5000 rpm, but maybe I can ask him to push it to 5500...

 

I've got a C4 transmission that was recently renovated with Red Eagle kit and shift kit.

Edited August 15, 2013 by Kaspar

[cphsonic 11]

Hej Kaspar

 

His weight has no influence, maybe only to the positive side. Less slippage on the rollers. Who are you using?

If the max torque and max HP has already happened by 5000 there is no reason at all to go higher. You wont be driving at that RPM.

 

Nice looking coupe!

 

mvh Hans

[Kaspar 21]

Hej Hans.

I'm using "KJ Biler & MC". They've done a bunch of other work on the car, that I am very pleased with, but I guess they hadn't much experience with dyno testing old fords.

[THE EVIL TW1N 12]

I'll be going back next thursday, but is there anything I should look for/ask for him to do, when he does the dyno?

Too bad the test-guy is quite a big fella, but I'll try to remove all other unnecessary weight ;-)

 

The Edelbrock chart said that their HP test peaked at 6500 rpm, but the dyne-guy didn't really dare to go that high. He stopped it at 5000 rpm, but maybe I can ask him to push it to 5500...

 

I've got a C4 transmission that was recently renovated with Red Eagle kit and shift kit.

The weight will make zero difference on the dyno, as was also posted by someone else.

 

That cam in that package is plenty healthy to make power past 5000 rpm, I would guess closer to 6000 before dropping off. What's the air/fuel ratio look like? Maybe running lean? Or even rich? Something is mismatched in your combo probably. What size exhaust are you running? Those Tri-Y's are probably not helping too much, you probably should move up to long tubes. Also, you will need a higher stall converter (I didnt see that listed on your post), somewhere in the neighborhood of 3000-3500.

 

Could be that the cam was installed a couple degrees retarded. Was it degreed, or installed straight up?

[sportsroof69 13]

Does he have a wideband in it? It should make power closer to 6000.

[Kaspar 21]

Aw man, I don't know anything about all these technicalities. I didn't built the upgrade myself and have very little knowledge about it. Though I do know that both the timing and carburetor are set optimal and that I'm running 2" exhausts. We'll see thursday what it all reads...

[THE EVIL TW1N 12]

2" is too small IMO, you would be better served with 2.5".

[Kaspar 21]

Sorry I meant I have 2.25" exhausts.

[MikeStang 247]

What kinda carburetor and Distributor do you have?

I would take a power valve or 2 with me, and a few sets of jets with me...maybe 2 sizes up and 2 down.....have them set the timing at 32 degrees and work from there...

You need to request that they give you the Dyno sheets showing the Graph, and the AFR on the first pull....This way you will see if the AFR needs to be adjusted, and you can make changes from there if they will let you...I dont know what kinda time or how many pulls you will get tho.

Timing and jetting can play a big role in making power....Most of the aluminum heads that I have run seem to have taken a bit more timing to get where they needed to be.

When you get a new converter I recommend one place and one place only...Stay away from the off the shelf crap.Call Continental Converters and tell them what you have...Year, make and model of the car, gear ratio, transmission and motor size and horsepower since you will know it.

They will build a converter that will perform wonderfully, or they will build it to your specifications.

I had a 10" built for my 455 pontiac....I specified a 2800 flash, and the ability to hold with twin turbos or Nitrous...I also said I wanted it to drive like a normal car.

Well I can tell you this....I picked up 3 tenths in the 1/4 mile, and there is pretty much no flash when you drive it normally, its just like driving a normal car.

However when you mash the go pedal it flashes to 2800 and away you go, and it holds that on boost, or spraying....Hands down the best converter I have ever owned, and there is virtually no slippage on the big end.

you may also want to readjust your valves...alot of time when you install the new cam and heads etc, the valves will go out of adjustment...not saying it happens every time tho....When I built my 408 and we dynoed it It was making great power, then it dropped like 25 hp...we pulled valve covers and one valve had went out of adjustment some how...adjusted it and pulled again and the power was back....

Check all the Basics.

Mike