I'm running out of "old tricks" on my 350 and want to see if I can sneak a little more ET out of it. Combo is in my sig, Comp cam is already in it but the weather is a bit too warm to get a good number out of the car compared to the perfect air that I ran my best with the stock cam in. Yesterday my best pass was a 14.08 with a 3050' density altitude. I just swapped my 3.23s for 3.73s and picked up about a tenth and a half from what I would normally run with the air conditions yesterday. Now that I have the gears done, I'll be trying a q-jet(thanks Larry!) to see if there's any gain to be had there. A/Fs are perfect already with the Holley, but I'll see if it likes the q-jet better. Timing is curved in perfectly and I can't find any more gain there. Car dead hooks, no spin at all with 60 foots in the 1.85 range(usually goes 1.7x when it's cooler out). Race weight yesterday was 3761 with me in it and a 1/2 tank. If there's anything you think might pick me up a little, post it, my ears are open.
Artie, can you tell us some of the things you've tried previously that maybe didn't work so well? Might kill some of our suggestions right off the bat. Pretty good numbers so far, I'd say! Devon
Stuff that didn't work or wasn't worth it: Removed tailpipes, added turndowns. Picked up .0012-.0016 but gave me a headache. Gain was not worth it, tailpipes are back on. Tighter converter, picked up 1-2 MPH but lost 2.5 tenths on ET. More timing and 100 octane avgas, no noticeable gain. Removed air cleaner, actually slowed down .0008-.001. Ran engine 2 quarts low on oil to see if there was any gain from less load on oil pump at higher RPMs and reduce windage(old super stock trick, but they run even less oil:eek2: ). No noticeable gain over my standard of 1/2 a quart low. Softer rear springs, all it did was squat more, unload the tires when it bottomed out, then unloaded the tires again when it bounced back up. Aborted pass and changed springs in the pits. No rear swaybar for less weight, drove the car around the block and put it right back on (I removed the front a long time ago). Scraped all undercoating off rear frame that I could reach and painted with black engine enamel instead. Removed 1.8 lbs in 2 hours and said f--- this, the rest of it is still there as it just wasn't worth the effort. Stuff I already did: 4 wheel drum brakes are adjusted for zero drag, also have aluminum drums in the rear. Lightweight wheels/tires, had 15X3.5" fronts but did not lose anything going to a 15X6 with a street radial at 40PSI. Electric dual fan set up (spare from my GN). Had this in for almost 2 years but will be making a small mod. 3.23s with 25.4", 26", 27.1", and 28" tall tires, it liked the 25.4" best so I traded my 3.23s for a friend's 3.73s out of his GN Removed spare tire/jack, unnecessary tools and anything that weighed more than a pound or two unless I need it to race (helmet, etc.). Stuff I plan to try: Waiting for my microswitch and relay to get here so I can run the turn-on circuit for the fan through the normally closed circuit of the relay. I'll use the microswitch to activate the relay at WOT and shut off the fan. I'm doing it this way so failure of the relay coil or switch will still allow fan operation, it just won't cut out at WOT if something fails. I'm going to use some mockup clay, then install a R45LTS (LTS=Long Tapered Seat) spark plug to see if there's enough room for it to not hit the piston at TDC. The reason I'm trying this is to see if reducing the chamber volume gains me any power. If it fits, I'll see how it affects combustion chamber temps (by reading EGT). I think that this will have a propensity for detonation as the spark plug threads hanging into the chamber will be a pretty good thermal conductor, the only way I'll know for sure is if I try it. Index the plugs, I haven't done this for years but still have my old index washer set. Probably no gain but all I'll lose is some time. That's all I can think of right now, have to go through my notes to find more. I'll dig through the logbooks this week and see what other stuff I forgot.
Your number is great for a low comp stock 350! Too low compression is not allowing you to run a large cam, and no head porting to take advantage of the cam are the only reasons you can not get into the 12s in my opinion. Great work now all you need is head porting, shaving to raise compression and good cam! Since you have a low comp engine, you are pretty limited on the cam selection unless you have the heads shaved and you have done everything else you could really do without modifying the shortblock. The 260 cam will be an improvement over stock but not sure how much larger you want to go without loosing the bottom end... The TA 212 cam will be your best bet if you do go for a cam swap in my opinion. NHRA guys are running 11s using the Q jet, stock intake, no head porting, stock valves, stock lift on cam, ect but where they make the power is in the duration on the cam, having an 60 thou overbore to help the heads breath, and decking the block to get compression up over 10.8:1. They only make about 360 hp but the cars run 4.56 gears, and must be set up REALLY well. Sonny Seal told me once that the Buick 350 is a torque engine and to focus on that not HP, and also said the 350 heads are constipated so head porting especially on the exhaust side and an overbore will help evacuate the cylinder. For the spacer you say 1" but is it open or 4 hole? If you have room a 2" 4 hole spacer may help. There is some dyno info here talking about the lack of gains from a TA intake and the success of a 4 hole spacer: http://www.v8buick.com/showthread.php?t=54585&highlight=ta+intake+dyno+testing
Glad you picked up some with the 3.73's Artie. You know I'm no help but: I've got that clean Chromed front bumper with your name all over it that should take off a few tenths:laugh:
Not yet, but have been thinking about it. I'll grab it below the bumper though, don't want to pull the bulbs out.
It's a 4-hole spacer, I need to measure hood clearance as I've been considering adding another 1" spacer. The only reason the Comp went in is that the stock cam was worn and I had the 260H here. I had gotten the cam for $75 a while back and paid another $70 for a set of lifters. I don't want to go internal on this 350 as I have too many money pit builds going on between my BBB and my turbo 6 powered race car in progress.
I've run the R45LTS plugs in my '69 350 with TRW forged pistons and didn't have any problems with clearance. The extra threads do get carbon buildup on them so don't leave them in too long or they get a little tough to remove. I also used to take the time to index the plugs and also used to grind the strap back half way with the Dremel. Not a big gain, but it did seem to make a difference.
What air cleaner set up do you use? Are you using a stock 4 bbl air cleaner? Or an aftermarket style that shows most of the filter. I always used my stock air cleaner on my Nova :eek2: I would flip the air cleaner lid and only have around a half of inch of gap exposed. It would always fell quicker to me then any other way. But then again I was only a local street racer back in the day and never ran a track. I believe with a 4 bbl stock lid if it is flipped the gap is too big. You would have to modifly an air clearner. Maybe you can modifly a 2 bbl air cleaner to fit a 4 bbl. Just an idea :beer
The long reach plugs have usually been worth a couple of hundreds of a second in any engine I've tried them in, 455 or 350, high or low compression. Never had a clearance problem. I usually used R42LTS with the higher compression although these days I'm using NGK TR55(#3951) which is the equalivent of a 43-44 AC plug. Only $2 each at Advance. I do have a look at them every now and then so that keeps the threads clean. How about some air bags in the back springs. I pump mine right up to 25-30 psi on the pass side and just 2-5 psi in the driver one at the track. Weaker springs was the wrong way to go although maybe weaker on the driver side with the stronger spring on the pass side along with the airbag pumped up in it. I used to run a station wagon spring in the pass side along with the airbag. The only problem was when letting go of the gas the car would feel funny until the chassis settled down. When you're driving around you pump the driver side up and let most of the air out of the pass side to level the car off. You'll need some help there anyway if you go the 455 route down the road. A Q-Jet might be worth something when you get it all set up. In my experience with 350's an 800 cfm one never ran any better than a 750 cfm unit. Looking at how mild your combo is the 750 DP you have might be all it needs but it is worth a try. How about that spacer trick where you run a 1" four hole and then a 1" open underneath it, assuming hood clearance. I read about that a few places now. I'd like to try it but I don't have the hood clearance for sure. Right now I run a Thermoquad with a four hole spacer and a 1"x2" notch in the Edelbrock's plenum divider on my 455. Those stock engines aren't as stock as they appear. Acid etching and sandblasting the ports to make them flow better and look stock. The cam is also probably in the area of 240-250 @.050". The compression is 10.8 but that is probably for the low compression '71 and up engine. Converter is skyhigh also. That and all the detail work is what does it like no power steering, brakes or anything that hints at power loss or weighs too much. Lots more to a "stocker" than meets the eye.
Thanks guys for the input. I'll just drop the plugs in knowing that they'll fit. I have a few sets of TR55s here from helping some guys out with LS1 stuff, I use them exclusively for LS series NA combos, TR6s for nitrous/boosted ones. I'll index a set and throw 'em in this weekend. I already have the open element 14" air cleaner installed. As far as the rear springs, I have gone to a stiffer spring (not the variable rate) I picked out of the TRW catalog and the car leaves good, no need for airbags. The rear swaybar is 1 1/8" so it leaves pretty level. http://www.davemilcarek.com/050909e/pages/5-9-1S 203.htm That pic is with the 3.23s and 26" tires. As mentioned above, a glass hood is in my near future for a little more weight reduction. My next points race is a week from Saturday, I lost in the final this weekend and am not happy about it. I'll have track results then, hopefully this stuff shows me some good results :TU:
Artie, Without knowing your complete combo, I think you're just about there with squeeking out some ET. The plugs and ram air suggestions are good for a little gain. Adding a 1/2" open spacer on bottom will give you a little bit on the top end. Without any port or bowl work you just "hit the wall" when it comes to these engines. Anything else you can do will have to be on the car itself.
Ideas; Weight Reduction: - Remove Jute padding out from under the carpet. Aparently all together this stuff weighs close to 70lbs. When i removed mine, i could barely lift it since it had soaked in alot of moisture over the years. If you dont want to leave the floor bare (because of noise and heat) replace it with dynamat, or Acoustic Floor matt. http://www.owenscorning.com/quietzone/pdfs/QZFloor_brochure.pdf That stuff is the exact same material as a "floating noodle" that you see in wave pools. Its a porous foam, with sealed cells on the outer layers to repell moisture. Weighs just about nothing, and provides some sound deadning. You may be able to find similar material for cheaper (but as far as i know Owens Corning is the only one making it in Matt form). - Remove inner fenders. -Remove seats, etc... (you say race weight is around 3700? ) you may have already done alot of this. Timing:] - I know you said its perfect, but id like to know what it is. Are you running any MSD or Crane, ignition stuff? - You may try longer plugs, and also may want to see what sort of a result you get running a colder/hotter plug. Im not knowledgeable enough to know which is better, but nitrous and forced induction guys run colder, and low comp guys try to run hotter. Must be a magic heat range for combustion that works. Fuel delivery: - 750 DP, 4 corner idle or not? <---- I never realized how much of a difference this actually makes until i was forced to switch to a carb without 4 corner idle with no other engine mods. 4 corner gives you a much more "explosive" start, than without, especailly from low revs. - Fuel pressure monitoring. Have you checked what the pressure is going down the track? What sort of a pump are you running? What sort of a fuel filter are you running? Heat management: -Might want to try a couple of old hot rodder tricks to pick up a tiny bit of power. Not sure if you can actually quantify this into ET, but it will lower your temps a bit. - Exhaust wrap. (lots of arguments about weather this works.) High heat, low density, faster flow? Definately lowers your under hood temps though. - Carb heat sheild. - Straight water, instead of a 50/50 antifreeze ratio in the rad. - Ice on the intake. Thats all i got for now.
Artie- I would say you have been as thorough as you can be. Cold air kit is about all I see you doing for any gains. Indexing or even changing the plugs I think will be wasting time and money. Cold air is a sure thing! How bout one of those Moroso fuel coolers too...just a thought:TU:
Can you reduce some parasitic hp loss from items like the radiator fan, alternator, or water pump? ....turn off the alternator (switch in field coil circuit?) ....under drive the accessories with different pulley sizes. .....power steering, or manual box? ....electric water pump. I doubt aerodynamic drag comes into play at those speeds, but stuff like front spoilers, blocking off openings in grille area or raising the rear of the hood might be beneficial. It's already launching like a beast... You need more hp!
