We're booked for Wednesday and getting my pal Kenny's Firebird ready for the chassis dyno. We were setting the lash the other day (and replacing a few broken polylocks) and I just happened to have the camera handy....
The basic combo is:
67 Firebird convert
400 Pontiac
BME rods and pistons
7.5:1
Ported E heads, intake flows 320 @ around .700 lift
Ultradyne solid roller, 276@ .050",.630" w/1.5 's, on 112
Kuhl 6-71, 30% overdriven (that is not a typo!)
two 9375 1050 carbs
2" Hedman race headers
3&1/2" exhaust to the axle, with Scott Brown X pipe and Hooker Aero Chamber mufflers
TH400, Art Carr 10" blower converter
4.56 12 bolt
29x10.5 "W" Hoosiers
the shortblock is getting tired, it's been bored/honed and re-ringed a few times now, piston to wall is getting very loose and this block is about done. It is just a 2 barrel 400 block from a Catalina and nothing special, and I know Kenny will just laugh if it blows up, as long as he makes beaucoup HP.
We can't drive the blower any harder, but we can slow it if the 30% proves to be too much. It sure feels strong on the street though....
The burning question:
how much HP/TQ will it make,
assuming it doesn't blow up immediately?
we're going to Advanced Chassis Dyno in the Sterling Heights area this time around.
We will have a Compucar 1000HP plate kit on hand, but that is just for S&G, and not to be counted in.
Guesses, anyone?
Cool engine! I bet it makes lots of horsepower just before the crankshaft snout and balancer go flying of the engine! Stand back!
Weak cast iron crankshafts are the problem with supercharging these great engines. I was around the supercharged Pontiac funny cars in the 1960's and the crankshafts couldn't drive the superchargers without snapping the snout off.
Let us know how it comes out.
Dennis Moore
1st problem:
The nitrous solonoids were not working. wiring? dunno. No time to figure it out.
2nd problem:
The dyno operator was an hour late, even though the date had been set up for close to a week. So we sat around and killed some time for awhile. During this time we started talking about buying a dyno, getting a shop and starting our own business with it.....
3rd problem:
Once the guy arrived, he immediately brought up the fact we couldn't get O2 readings because of the leaded fuel. Gee Whiz, Kenny asked him about that on the phone and he said "no problem", yet after we arrived there all of a sudden it was a no-can-do situation. Why the sudden change of heart? Perhaps being too busy, and not paying attention to what's said on the phone? Whatever it was, Kenny wasn't happy.
That mess presented us with two choices:
1. Tell the guy thanks for wasting our day, tell him he owes us about $50 for fuel, and go home pissed off.
2. Be a good sport, run it anyway, do some plug checks to at least see if it's going lean, and get some HP numbers.
Thankfully the latter choice was made, and we were on.
The dyno ended up being a Dynojet which was fine with me.
1st run, tried to be conservative, kept the rpm down somewhat to 6300-6400.
574 RWHP, 539 TQ
Coolant blew out the overflow....other than that no issues....plugs were well into the safe zone with lots of color....we were good to go!
2nd run, didn't let it cool down for very long, but brought the rpm up slightly to 6600-ish
601 RWHP, 574 TQ
3rd run, we got to talking about the air filters.
Kuhl (the supercharger guru) mentioned his air cleaner setup cost 80HP, however Kenny had put on larger elements to try and avoid that. Only one way to find out how well it worked:
615 RWHP, 508 TQ
rpm was run up to 6600-6700.
So the larger elements work reasonably well....cool....
At this point the car sat and cooled for a long time while the car owner and dyno guy BSed, and I wandered around the shop checking out all the cool junk.
I got to thinking the next run should be balls to the wall but for some reason they kept the rpm down again. I was looking forward to seeing 7200-7400 out of it (the rev limiter is usually set to 7500) but I guess the dyno guy wanted to stay conservative.
He must have been out of oil dri or something
Even after sitting, the supercharger case and the heads were still hot enough to cook an egg on but apparently what little they cooled did help..air cleaners were also left off from the previous run:
622 RWHP, 561 TQ , car was run up to 6600-6700 or so.
That was the best of the day, and the end of our time slot.
The funny thing is that every single run was ended WELL before HP showed any signs of falling off.....in fact right when she was starting to really scream that was the end. That was a little frustrating for me to see.
I guess the disappointment after finding out about the lack of a/f readings made everything laid back and nobody made a point of saying "TAKE IT OVER 7 GRAND!", but doggone it...if it would have been mine I would have made sure the guy knew to do that......oh well.
I have no doubt that it would have seen somewhere between 630-650 RWHP had the rpm been allowed to go higher, but as it was we knew we had 750 HP + at the flywheel.....and it didn't blow up....so what the heck, that was good enough.
I like Advanced Chassis Dyno's facility and will probably go back there. Even though the other one (Monkeywrench racing) I went to before with the Dynapack is repeatable as far as HP, I found the torque numbers to be a complete mess there...and the Dynapack simply can't handle any more TQ than I am currently making, no matter what the manufacturer says....when I ran the GTX the computer complained about it reaching max torque capacity several times.
So for quite some time to come, I will remain the Monkeywrench racing DYNO KING because it can't handle any more than I have and the owner is afraid of me
breaking it Both are repeatable and nice machines but the Dynojet can handle more than the Dynapack3000 so that makes it an easy decision for me.
We left, made it within 2 miles of home, then the right slick went flat
Had to stop and pump it up a couple times, and finally made it.
Left again (in the Polara), topped it off with an Applebee's all you can eat ribs dinner, went back home fat dumb and happy, and it was a good day
Blown:
Horesepower, schmorsepower...who gives a ****? I just wanna BANG the chick in your avatar...
LO
[ September 11, 2003, 11:57 AM: Message edited by: LakesOnly ]
LakesOnly:
Blown:
Horesepower, schmorsepower...who gives a ****? I just wanna BANG the chick in your avatar...
LOYou.....and about 10 million other guys
Blown 472:
<SNIP> I was looking forward to seeing 7200-7400 out of it (the rev limiter is usually set to 7500) but I guess the dyno guy wanted to stay conservative.
He must have been out of oil dri or something
LMAO Great line.
Loved hearing about your experience. I was bracing myself for your saying something like "the engine lunched when the snout wrung off on the way home at 3000 rpm during a light throttle upshift."
Just the slick going down...whew.
DaveA
That is so cool! I am glad you guys did not wound the catalina block.Old pontiacs are cool. I lost interest when we had "corporate motors".What in the hell was an olds 403 doing in a trans am? I have an invitation for some winter fun. I worked for a shelby/cobra retoration guy when I was 16.He has a complete shop right close to where I live.I bet you would like to check it out sometime when the snow flies.I once saw a boss 429 complete on his engine stand.It was perfect as far a stock goes.He is kind of a prick till you get to know him. Then he is a bigger prick.But he knows his fords and really isn't that bad.Stay Cool
DEL51:
That is so cool! I am glad you guys did not wound the catalina block.Old pontiacs are cool. I lost interest when we had "corporate motors".What in the hell was an olds 403 doing in a trans am? I have an invitation for some winter fun. I worked for a shelby/cobra retoration guy when I was 16.He has a complete shop right close to where I live.I bet you would like to check it out sometime when the snow flies.I once saw a boss 429 complete on his engine stand.It was perfect as far a stock goes.He is kind of a prick till you get to know him. Then he is a bigger prick.But he knows his fords and really isn't that bad.Stay Cool Heck yeah, got to do something when it is raining ice.
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