What cam to get with my current build?
I'm understanding that you really need to match the heads, intake, and cam on a custom engine, and maybe even the carb, but I don't know how & don't want to take my mechanic's advice on such a crucial issue, which is that ďit doesn't matter that muchĒ.
All parts of the engine are new, and so before I put it in the 78 El camino, I want to be damn sure that the right cam is in there. It may be the second time I'v replaced it, but I don't really care as long as I get it right.
The engine had a lunati roller cam that was supposed to just be a stock replacement, and my mechanic didn't get the specs off the cam even though I asked him to before he put it in. The bearings got messed up because he put the wrong flywheel on there & so it hadnít really even been driven before I had to have the engine taken out and I thought I would use this opportunity to put in a Lunati Voodoo Roller cam that my mechanic had. I asked for him to write down the specs for it, but he did not write down the specs as I had asked. (I knowÖ***!?!)
He thinks the lift is 490 and the compression ratio is 10:1.
I went to the Lunati website and looked at all the Roller Voodoo cams for one matching that description and the closest I could find was this one:
http://www.lunatipower.com/Product.aspx?id=1993&gid=290 Part Number 60132
ē Cam Specs:
Advertised Duration (Int/Exh): 273/279
Duration @ .050 (Int/Exh): 243/249
Gross Valve Lift (Int/Exh): .578/.585
Valve Lash (Int/Exh): 016/016
RPM Range: 2600-7000
Either way, I feel like I need to know what kind of cam is in the car or Iíd be a fool, so Iím going to have to have him take the part number down and see if it fits with the setup or not. If not, Iím going to get a new one put in. He is a friend of mine, so heís not trying to screw me over, but I feel like I am risking getting screwed if I donít get this setup right.
Once it is in, Iím getting my car to a shop for fine tuning & a checkup, but I donít want to have to pay someone else to take the motor out again and change the cam. (since it is already out).
Hereís the setup Iíve got going, all new stuff.
350 SBC 4 bolt Main, Bored .06 machined at a racing shop
400 externally balanced crankshaft.
Keith Black Performance Dish Pistons, machined at a racing shop, with the rings & stuff for a stoker motor. ( I think this makes it a 389 stroker..?)
I was told I should not use flat top pistons b/c I would not have the compression to run pump gas
High volume & flow Oil pan & pump
ē 210cc intake runner aluminum sbc heads
2.02" intake and 1.60" ex. valves
All the specs are here - http://cgi.ebay.com/ebaymotors/New-c...Q5fCarQ5fParts
When I ordered them, I got them for a mild cam, (the lunati stock replacement cam that was in the motor)
Aluminum roller lifters, and aluminum roller rocker arms
ē The intake is a HI TECH TORQUE LINK INTAKE MANIFOLD
Designed by legendary engine builder Jim Mcfarland. This dual riser intake is a single plane manifold. (that sounds funny, is that possible?)
The manifold runners are extended in length by crossing over and feeding of the oposite side of the carb. This allows longer runner length than the typical Vic JR type manifold. Seems to allow a little more low end power (within the usable range of a single plane manifold) So your usable power band starts sooner. And the peak torque output is higher, much like a Cross Ram intake manifold.Edelbrok 4 barrel performance series
It is really tall so I had to get a low profile carb. I got an Edelbrock performance series 600 cfm 4 barrel. My neighbor came over one day & turned the knobs to ďshow me what they were forĒ so the factory tune is messed up. I see that I can get it performance tuned or fuel economy tuned. Since I assume I have to get it tuned anyway, Iíll get it performance tuned. If I really need to, I can get a 750 cfm.
MSD Streetfire Ignition, Taylor Wires, High output ac delco plugs, HEI Distributor, Large radiator, lightweight fan, new mechanical fuel pump,
( put in an electric without the control & flooded the heck out of the engine, then realized it was the msd ignition that was not working, so I sent it back & got another & put the old fuel pump back on & changed the plugs)
Has air conditioning & power options, which I want to keep.
New battery, waterpump, & high output alternator.
Cruise, power steering, power brakes.
350 turbo automatic transmission that you can also shift on the tree.
7.5 g-body rear end with 3.42 gears and a posi unit. The car weighs no more than 3,800 lbs
Hooker Long Tube Headers
Dual Flowmaster Delta Force exhaust
Spectre Musclecar Cold Air Intake (fits on top of the carb) I do not have this in hand yet, but I think it will fit, as it is 2.4 inches high, and I think thatís about what my breather is. Iím keeping it stock on the outside for a black knight clone job, so Iím barely getting the hood closed.
Regular street tires on 15Ē Rallyís with aftermarket shocks & front end
Thatís all I can think of that one might need to know about the setup
I realize I am an idiot for not buying a crate motor at the outset, but cannot change it now.
I would like to take it to the strip for a day to see what it feels like & what it runs. I donít think this car will corner well at all. I donít know what this car is leaning towards Ė lots of HP & torque or one or the other. Experts would know right away, but whatever cam would make this engine the most kick *** is the one I want.
Basically whatever will make the car worth as close to $12k as possible for when I try to get as much of my money back as possible (hahaha)
Thanks very much for reading this long cam fit question & for any help & suggestions.
the cam you have listed will be too big for a 3.42 gear and a stock converter. a cam like that needs 10-11:1 cr, 4.11 gears, and a 3000-3500 stall.
with a 3.42 gear and stock stall I would stay under 270 degrees of duration (seat to seat). A cam like this can run 10:1 cr with aluminum heads and would require 9.5:1 as a minimum. a 2400 stall would be nice.
how much are the pistons dished? how many cc's?
edelbrock carbs are terrible. get a holley 3310 with a edelbrock rpm intake (not air gap, use a regular rpm).
My question is after he goofed on the first go round why use him again?
Your the customer, you should have all say on your engine and when you ask him for specs he should give them "it really don`t matter much" spells out to me a few things, one, he don`t care, two, he may not know what he`s doing and that`s the best answer he can give.
Hereís the specs on the pistons:
Keith Black/KB Pistons KB135-060
Pistons, Hypereutectic, Dish, 4.060 in. Bore, 5/64 in., 5/64 in., 3/16 in
ore (in) 4.060 in.
Bore (mm) 103.124mm
Piston Style Dish, with two valve reliefs
Piston Material Hypereutectic aluminum
Compression Distance (in) 1.433 in.
Piston Head Volume (cc) +18.00cc
Wrist Pin Style Press-fit or floating
Pin Diameter (in) 0.927 in.
Piston Ring Thickness 5/64 in. x 5/64 in. x 3/16 in.
Quantity Sold as a set of 8.
Notes D shaped recess. Piston weight 500g, pin weight 145g.
Here are the numbers on the heads
Intake Flow Exhaust Flow
Straight plug 64cc combustion cambers
Valve springs installed @ 1.80 with 140# closed pressure
Springs good to 600 lift
These heads are best suited for engines in the 350-550hp range using solid flat tappet or hydraulic roller lifters.
He's fixing the issue, but I forsee another issue with the wrong cam, so I want to head this one off & get my car outta there & back to my house after he puts the motor back in. I don't want him to put the motor back in the car until I have the best cam for the rest of the engine, if that makes sense
you will have about 9.5:1 cr.
get a mild cam to match the compression, gear, and stall.
a cam with about 260 degrees duration (seat to seat) will work well.
I would get a cam with 110 lsa, 260 degrees on the intake and 260 degrees on the exhaust. no need for more duration on the exhaust.
sure, those cams will have only a slight lopy, very slight. vacuum should be good, 16 to 17 inhg depending which cam you choose from that group.
Thank you SOO much!!!
This would have been a nightmare if the engine got put in with the wrong cam
I got my engine back to my house & took it out of the car & found out what type of cam is actually in the engine.
Camshaft, Hydraulic Flat Tappet, Advertised Duration 284/284, Lift .458/.458 Lobe Separation (degrees) 110
On one hand, it is a lot closer to what i need in the car, on the other hand, I was told it was a Voodoo Hydraulic Roller Cam, so I paid $100 bucks for it, but I think that was all a lie and there was never any cam change.
Is the cam in there good for the engine, or just blah?
I THINK that with an rpm range starting at 1,500 I don't need to do anything to my 350TH like add a stall converter, so that may be good.
I had the engine made for a 78 el camino, but realized I would not be able to get that $$ back out of the car, so I bought a 1980 z28 with T-Tops that had a good running 305 sbc with a 350TH, that I could actually make sure worked, as it was in the car, and put that in the El Camino, which brought my costs back in line with what the car is worth. provided that I can sell the camaro for $800 which would mean I got the El Camino an engine & tranny for $500 installed, that I know works well.
But if I wanted to get the $6k I have in my engine back out someday, I knew I needed to put it in a more valuable car, so I bought a 1973 z28 which was in "B" shape, but had no motor or trans.
This was my first venture into this stuff & I never expected all this, but it is fun learning, as long as I don't lose money in the end, and get to drive fun cars.
So, my "custom" 388 stroker is out of the car now, if there is anything I need to do to it, now is the time, if I need a stall converter, new cam, or bigger than stock oil pan. I will go ahead and get the Holley 750 carb and RPM manifold, as suggested above.
I had the engine in the 80 camaro for awhile to test and break it in and it runs extremely well from an idle, starting, sound, and burning rubber standpoint. I didn't have any guages hooked up, so I don't know the speeds or oil pressure, but it was not running hot & would get rubber starting and going into second.
I felt like there was too long a time from when my foot hit the gas to when the car took off, but I think the carb & intake change might fix that.
Anyway, that's it - Thanks for the advice. I guess if anyone wants to buy a 1980 z28 t-top roller for $800 contact me :)
ps - the vin & cowl were checked on all the cars & are both z/28s
The cam seems to be a little on the lazy side. with 284 advertised and only 218 at 0.050". The lift does match the duration at 0.050". The good thing is the cam will likely live a long life due to it's soft ramps.
should run a 2000 to 2200 rpm stall with a 3.42 gear.
The "new" 1973 z28 I got to put the engine in has a 3.73 gear ratio. I called Lunati this morning to try & decide whether it would be worth it to buy another cam and lifters & pay to have it professionally changed.
I was given this cam as a better one for this exact setup
Lunati Voodoo Hydraulic Flat Tappet, Advertised Duration 262/268, Lift .468/.489, Chevy, Small Block,
so I think I would be looking at $200 in parts + the install.
I'm not sure if the power increase would be worth the change, when I could get the Holley Carb & Intake that was mentioned for the same price, not to mention the engine runs well now and I don't want to jinx it, but then again, after all this, why settle for mediocre?
I ended up in a virtual dyno software thread here that I was going to use to determine the power gain from changing cams, but readers said the software was crap, so I didn't get it.
What I would LIKE to do is put a tremec 6 spd manual & supercharger in, but I think it would be money down a pit on the 73 camaro, b/c I would like to sell it eventually (in theory)
My advice is, if you are happy the way it runs now then don't mess with it.
|All times are GMT -6. The time now is 03:43 AM.|
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.