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sapsZ28
I did 1 3/4 headman headers 3 inch collector 3 inch xpipe,got rid of the H pipe, 3 inch 2 chamber flowmasters ended up not liking the magnaflows, also put in a 1/2 inch open phoenolic spacer breaths alot better and climbs the rpm ladder faster,I might have room for a 1 inch spacer that will be the next step,not alot of clearance under the Camaro but today i'll find out if it fits.
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saps Z28
Thats why I went with RFI supresiion wires and plugs for 3000kms and 3-1/2 months no noise through the radio,which is a constant noise not the winding rpm type due to rfi suppression or bad grounds this sound is like listening to the distributor firing order throgh a specific sound wave.
This all happened after I changed my cap & rotor and put new hei boots on after custom cutting to length my existing wires , they were way to long from the factory,all parts wereexact as the ones I tossed ,MSD and TAYLOR,. and last I put on a 1/2 inch spacer last weekend and there was a significant difference the car could breath and wind up under load better,last night I switched it and put in a 1 inch spacer ,phoenolic open bore,I only moved the car to park it in the garage but I think I finally woke up the beast .just from pedal feel and sound.althugh i will eventually check it again do spacers in the 1 inch range need the carb rejetted due to the air volume change in the plennum vs before. Thank YOU EVERYONE who has helped me along the way with my ride. |
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I think you are chasing a basic ignition problem.
The difference between a 1/2" spacer and no carb spacer is small at best and can only really be seen thru dyno or track testing (with traction) Generally it adds a bit more top end power. 5 to 12hp at the top[ end typical. You wont feel it in the seat of the pants. What you are feeling is a ignition issue. This car should scream with no spacer at all. You needs gears and traction and track or dyno time. (too bad I was not much help with the traction dept) Did you find some sticky tires for it? Check the length of the contact on the rotor. Some are short ( larger cap/rotor gap) emissions type. check the wires with a ohm meter. radio noise indicates gaps in the electrical path or the RFI Shielding is fubared. Check the center post in the cap under the coil. A stock resistor type one will burn up when using a hi voltage HEI coil and or MSD box. cehck it with a ohm meter. MSD sells steel ones. Flowmaster mufflers are loud and restrictive compared to Magnaflows. Uncap the car and add 12 to 18" collector extensions and you will see the difference. Been there done that. Last edited by F-BIRD'88; 08-04-2012 at 07:06 PM. |
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saps Z28
I changed the contact under the coil and it was all black with carbon on the spring as well the cap and rotor kit came with 2 contacts the [stock] one,and the Msd steel one which I used with dialetic grease,as for the traction issue no I have not adressed it yet, on a daily basis the cars tire will stay as is remember I use it city and hwy on a daily basis thats why I built it to drive it and enjoy it its my little time machine.ive made my tranny decision tremec 5 speed with a .68 overdrive and a 4.10 rear end ratio,i,ll check the ohm readings on the ignition system and let you know, Your right about the 1/2 inch spacer not a huge difference but there was a significant improvement with the 1 inch spacer,
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sapsZ28
In regards to the resistance for the ignition wires what type of numbers should I be looking for in regards to ohms or any other number. when it comes to electricity that is my weakness I dont understand it very well.
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saps Z28
Anyone outhere have any knowledge of ohms and or resistance for ignition wires I checked my grounds and they are intact I have 3 rear battery to the frame block to the firewall and alternator to the frame.
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What wires? brand? type (spiro core?) resistor, non resistor?
what are the ohm readings 1 thru -8. The longer wire will have a higher resistance use the K ohm scale (1000 okms) or 10K scale (10,000 ohms) You are looking for a unusual high resistance. radio noise? |
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sapsZ28
they are Taylor spiro pro's 8mm resisitor type Thanks for the ohm info I will do the redings and get back to you I am assuming the lower the reading the better.
As for the noise its not that winding radio noise its a static crackling sound on battery power there is no noise only when the car is running and its a very low frequency soundit goes through all four speakers but I'm not sure if it goes through the sub i have 2 separate amps I'll get back to you.Thanks again |
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sapsZ28
well I figured out why at times my motor stumbled and momentarily lost power then csme bsck to life I only had a 40 GPH freefflow fuel pump on it rated to 300hp I put a edelbrock performer rpm fuel pump on it which free flows 110 gph and holy crap the motor really came to life before it would pull to 6500 rpm but after 5000 rpm it would take its time now even with the 3:42 gear the car goes to 6500 rpm in a heartbeat ,what a bonehed move I pulled but when I make a mistake i admit it it runs so much better now,I also bypassed the regulator since the pump is preset for 6 psi which is what my ultra 750 calls for,Thanks agaim everyone for all your advice and input.
Now we start to save for a 5 speed.happy cruising everyone |
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Yup, the fuel pump has to be able to keep up with the engine fuel demand at WOT.
On your mechanical pump watch the rubber hose on the inlet side. The one that goes from the frame to the pump) Sometimes when this hose gets hot it collapses under demand (WOT) . Avoid sharp right angle fuel fittings. Keep the fuel lines away from header/exhaust system heat, especialy on the feed side of the mechanical pump. A AFR gauge will show you if the WOT high rpm fuel curve is right. I believe the clocking of the lower pump houseing (fuel inlet position) is adjustable. |
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sapsZ28
Hi F-Bird with the new pump and exhaust and a custom diff pinion snubber,22 degrees initial and 40 total I had a 1,91 60 ft 12,79et @110.68 mph I launched it at 3100rpm its getting better plus I drove it 340 KM round trip to cayuga and back next up is ported heads with a 2.08 int valve 5 and a 125 shot of spray over the winter Thanks for the advice. I know gears and tire when I fry my rears I will go with a drag radial BFG I still want streetability and some handling
And thank you for all your input. Thank you all |
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12.79@110+ now you are getting somewhere. 40deg timing @wot is a lot.
Try richer jets and a bit less timing 36ish. More track time to test will bring it around. Good stuff. I have been right where you are at: Haveing to work thru and solve all the littler stuff like ignition issues and fuel flow etc. |
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