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  #31 (permalink)  
Old 07-14-2012, 11:02 PM
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Quote:
Originally Posted by sapsz28 View Post
I have had the rear end apart and the ring gear is stamped Richmond,3:42 my tire is 28 inches tall measured fully top to bottom with a straight edge and from the axle centerline X2 it's a firestone fire hawk 255/60/15 ,still can't understand why I rev 2900 @ 60 mph?. The teeth on the ring gear are 41 and the pinion teeth have 12 which comes out to 3:41666=3:42 .Going through the traps I'm pushing 3rd gear @ 6600rpm I can't figure it out .in the end I figure the dyne could either have not been calibrated or there was some funny business going on.in 1st gear @2200 rpm when I floor it the rear tires light up like Christmas tree no clutch dropping just pedal to the metal I'm going to try a mustang dyne with and without the exhaust hooked up to see if my flow masters are holding anything back,if they are then a higher cfm rated muffler will be put on.
PS has anyone ever had any problems with the MSD STREETFIRE HEI Unit.
The thing that makes the most sense is a tach that's out of calibration. You could have clutch slip, but if you did I'd expect you to smell it and notice the degraded hook up and/or chatter that happens when the clutch plate and flywheel/PP glazes from slippage.

There are thousands of MSD Streetfire distributors running just fine. But that doesn't mean you couldn't have a bad one. Easiest thing IMO is to swap it out for a known good unit- even a stocker, as long as the advance curve is correct.

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  #32 (permalink)  
Old 07-15-2012, 12:47 AM
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61 MPH should be 2500 RPM with 28" tires and a 3.42 axle.
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  #33 (permalink)  
Old 07-15-2012, 09:55 AM
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Horsepower stumped

I have tried 3 different tachometers 4 if I include the factory one ,they were an auto gauge,auto meter z series, and a sun pro all set at the 8 cylinder setting where applicable,as well with a timing gun with a digital readout on it and all of these pieces showed the same rpm across the board in neutral and under load as well as the dynojet dyne I've been on unless my tranny's 4th gear is not a 1.1 final drive but I'm not prepared to open her up unless she's broken,
As far as the 220cc AFR full cnc race port heads are concerned does anyone think they will make enough of a difference over the RHS 200cc's I have now aside from the bigger runners the afr's have 2.10 intake valves versus 2.02 I now have exhaust remains the same at 1.60, and the afr's flow45cfm more than the rhs's, as well from the hydraulic roller set up I will go solid cam flat or solid roller I've not decided yet ,my hydraulic roller set up is
241int@50 245ex@ 50. 541int lift 565ex with 1.5 rockers, all howards products.
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  #34 (permalink)  
Old 07-15-2012, 10:21 AM
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your heads are more than adequate.Flow test them and see what the porter says?Once you have flow tested your heads you can determine if your current cam is the correct choice or if you need more. Local guy here has similar heads on a 10.8s 350 powered 68 Camaro.He too is using a smaller cam similar to yours except solid.vic junior manifold,flowed HP holley,etc.not a street car anymore but still streetable.
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  #35 (permalink)  
Old 07-15-2012, 01:12 PM
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horsepower stumped

I definately want to keep the streetability and reliability aspect of the car,up untill now I've kept both although the cam is stretching it a bit my wife is still using it as a grocery getter,I quite sure the tremec with a 4.56 or 4.33 will make a world of difference.68* the 4.56 will give me a 3.10 final drive the 4.33 would give me a 2.95 final drive, I tgink I will port my RHS 200's and put in a 2.08 intake valve perhaps I'll switch springs from comp cams 987's to a beehive setup for less reciprocating mass and valvetrain stability. Thanks again everyone. As far as ignition wires go, again the taylors give me the best clearance issue on the plug side,perhaps i'll go with a different wire but taylor plug ends,i'll try a 1/2 inch phenolic spacer for some more air should I stick to a 4 hole to keep it dual plane or an open spacer, will it affect the air flow that much,anyone ever try it.
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  #36 (permalink)  
Old 07-15-2012, 01:28 PM
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spacer

You wont need a spacer for a Vic Jr manifold.I only use a 3.50 gear. The tremec has I believe 2.78 1st gear.That gives me close to 10:1 first gear over all ratio with a 27 inch street tire it does 54 ish mph in first.just over 2k at 60 mph.I use a solid roller and it buzzes flawlessly over 7k.I put a 6k chip in the rev limiter now as I have too much power to traction ratio atm.
You will have the same problem with the better manifold.If you used a 4.1 rear gear that would give you 11.4 :1 over all first gear. What over all first gear do you think is best?
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  #37 (permalink)  
Old 07-15-2012, 10:01 PM
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horsepower stumped

Its a stepin the right direction with a 4:33 rea end and a.68 overdrive I'll have a 2.93 final drive which is where I want to be on the highway with a 4:56 I'll have a 3.10 final drive again thats fine.
does anyone run dynomax ultraflo welded mufflers and if so how do they perform and sound, Thank you again everyone you have all been a great help
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  #38 (permalink)  
Old 07-17-2012, 07:39 PM
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horsepower stumped

Well i hace freed up the cats and installed 3 inch maganaflow 4inch round bullets HOLY CRAP F Bird you were so right the machine breaths abd does not run out of breath, last night I put her through her pace and she kept pulling and pulling I took her to 7000 rpm with no hesitation although I know I have to keep her no more than 6500 rpm cant wait to put in the 5 speed with 4.10's i'll keep you posted, oh yeah if like flow and loud go wiyh bullets
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  #39 (permalink)  
Old 07-20-2012, 12:16 PM
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Just a note,

Howards Cams also has a rev kit for Hydraulic Rollers.
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  #40 (permalink)  
Old 07-23-2012, 07:29 AM
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F-Bird how can I contact you to pick up the tires are they the M&H racemaster 275/60/15 my number is 905-839-9511 hm
416-729-4766 cell
e-mail gsapounakis@hotmail.com I'm in Pickering Whites rd and Finch
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  #41 (permalink)  
Old 07-24-2012, 09:52 AM
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horespower stumped

IN regards to timing i have 18 Gedgrees initial 36 total however i have my vaccum advance set to port vaccum and the timing raises to 53 degrees I have read in David Vizzards books that that is what a sbs with a large cam needs once were up to highway speeds,would port or full vaccum be better ,not only for mileage but for plug cleanliness and throtle response.
On the dyno though with no vaccum advance i picked up 27 ft-lbs more torque at the wheels,as well is it better to use nylon or plastis scews for the rotor and or weights so that there will be no spark jumping or arching,sometimes after 2 or 3 WOT runs,foe some reason it always happens at the track, I'll get a little hesitation regardless of the amount of time at WOT but if I let off momentarily everything rights itself back up,i've checked my fuel pressure and it does not drop at WOT under load it stays at 6 psi would jet extensionsand the right floats for clearance possibly help,my wires are brand new and tuked and taylored as far away from heat sources as possible with loom separators attached to the valve covers,I know some of you are not fans of taylor wires but they have the most clearance on the plug boot side of any 90 degree boot that i know of Ive melted MSD's and morosos and accel boots but the taylors seem to be doing fine.
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  #42 (permalink)  
Old 07-25-2012, 08:22 AM
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horswpower stumped

Okay I regapped my plugs to .35 even though the gm manual for 1980 says .45 with HEI. .35 for points But I went with your advice,however I just changed my plug boots 2 weeks ago and when I took them off the plugs to regap them the plugs were clean on the tips and tan in colour but the porcelan part of the plug was covered with carbon should that not be the cleanest part of the plug since it is covered buy the boot..
as for thr the prevvious comment the 1st 2 runs were my best then
I ran into those studdering problems after the the car /fuel lines got hot, makes .sense
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  #43 (permalink)  
Old 07-30-2012, 09:03 PM
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stumped

changed the cap & rotor also canged the #2 wire in side yhe old cap all the contacts had carbon and welding type marks but the #2 looks like it had been tig welded so far so good at 2500 i hammer it and she lights em up asfor the phase travel on hard deceleration i show 20 inches vaccum on 1/2 throttle or more vaccum goes to zero.
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  #44 (permalink)  
Old 08-02-2012, 11:12 PM
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sapsZ28

any advantage to locking out the timing and if so how is it done,As well after changing the cap and rotor and trimming the wires with proper looms,new hei boots etc I now have a constant zipper type sound coming from my stereo when the engine is runing ,but not under batery power ,
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  #45 (permalink)  
Old 08-03-2012, 12:20 AM
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chokin it.

I would aim for the exhaust size first, let it exhale, size it up.
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