What would you do?

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dustUoff

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Just wanting some opinions on what direction I should take my 360 build. This will be a 95% street car that I want to be a beast out of the hole, won't see much time past 6000 RPM. As of now the engine is a stock stroke 360, i've got KB 190 pistons, an old speed pro cam that's [email protected]"/304 rated/.453" in & ex. on 108 l/s with 88 degrees overlap, with some old 596, 1.88 valve heads that I'm doing some light port and polish work on myself. 727 with stock converter, 3.55 gears, and some Doug's headers. I don't have a ton of money to throw at it right now, maybe like $500 bucks. So I'm wondering what you guys would do? Upgrade my Torque Converter, throw all the money at getting the heads worked over, upgrade the cam, what do you think?
 
I agree with everyone else, in a 69 valiant with a very mild 360, 410 gear and 3800 converter the car ran 7.90's in an 1/8th mile. This car even had a Thermoquad carb and hi-po 340 exhaust manifolds. The converter picked it up almost a half second! With 355 gears, you wouldnt want that much stall but if you call Mancini Racing or Turbo Action, they will tell you what to run to get the performance you want. I used a Coan from Mancini Racing.
 
While the converter would be great for the track, I think a different cam would do better if you intend it to be a cruiser. About what static compression would you be running with those heads and pistons? What intake and carb? Are the valve springs set up for your current cam?

xe268h would be a good choice with stock converter and 3:55's if you want decent low end torque with some top end. xe262h if you want more low end. http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=627&sb=2
 
Well sounds like a converter would be a good way to go! Dano, my static CR should be right around 10.5 to 1 maybe just a Tad more. Running an Eddy performer dual plane intake with a 750 Holley. So do you think that xe268 would be the best choice for that low end grunt?
 
dustUoff said:
Well sounds like a converter would be a good way to go! Dano, my static CR should be right around 10.5 to 1 maybe just a Tad more. Running an Eddy performer dual plane intake with a 750 Holley. So do you think that xe268 would be the best choice for that low end grunt?
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With that compression, you could afford to go larger, but then you'd need the converter too. The intake, to me would be your limiting factor as it doesn't match the rpm band of the cam you have now (2800-6000) or the xe268h (1600-5800). Depends on what your willing to give up in what you have for your desired goal. You could go Stall and an intake to match your current cam, but then 3.55 might not be the best gearing either, which you can change later. With that static compression, gearing and converter considerations, I'd talk to someone about a custom cam.
The one you have seems pretty nasty to me for a 95% street car. Also consider the health of the transmission, it may not respond well to a hot cam and stall (heat) if stock and/or high mileage. Just food for thought.

FYI I run a Lunati 60403 in my 340, but I have a 4 speed and 3.91 gears with ported heads, Stealth Intake, 750 Holley, and Dougs headers.
 
I ran those pistons in a .060" 360, With 915heads & a .039" gasket, the compression came in at 10.3.1, That cam is WAY too small for that compression, I ran the XE284H with adj. rockers an it was quite mild, it had 185-190 psi cranking pressure, RPM intake & a 750dp, 3000 stall & 4.56 gears, It kicked *** in a full dressed 73 Swinger show car, this way at 3700ft. Alt., The torque was unbelievable, I had a 6200 chip in the MSD & at hit it with ease through all gears. A larger cam will definitly benifit you, That little cam you have will most likely cause detination with those pistons, you'll have well over 200 psi, invest in a larger cam, like said, A good converter to match the cam & at least a 4.30 gear, you'll love it.
 
JoeDust451 said:
That cam is WAY too small for that compression, That little cam you have will most likely cause detonation with those pistons, you'll have well over 200 psi, invest in a larger cam, like said, A good converter to match the cam & at least a 4.30 gear, you'll love it.
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That is what I figured as well, too much static/dynamic compression for the smaller cams that work with the intake, 3.55's and stock converter.

Some things needs to change regardless in the combo for it to work together and for ~$500.....

My vote for the money for a 95% street car, lower static compression to ~9:1 (replace pistons), Lunati 60401 or Comp xe262H, reuse Performer, 750 Holley, 3.55's and stock trans/converter.

If you willing to give up driveability, Victor or M1 Intake, Stall matched to cam, at least 4:10 gears, Shift kit/trans rebuild, use existing cam, 750 Holley, Port heads

OP, is your short block assembled or are these just parts on hand?
 
Alright, JoeDust and Dano... thanks a ton for the insight! So the cam that I have was the one that was in the car when I bought it which is why I didn't know much about it till I recently pulled the engine. It definitely had a nice lope to it but sounds like with the new pistons it may be a little small. I've been looking at the MP 284/.484 cam... would that perform well with my combo? Also, I know the intake is pretty old but if I ported it out would it flow well enough to work? Sounds like i've got some things to consider... but if it were you, and you wanted to keep the 190 pistons, would you go for the cam upgrade and worry about the converter and gearing later? Dano-The engine is disassembled, on a stand right now and all the parts listed are parts on hand.
 
dustUoff said:
Alright, JoeDust and Dano... thanks a ton for the insight! So the cam that I have was the one that was in the car when I bought it which is why I didn't know much about it till I recently pulled the engine. It definitely had a nice lope to it but sounds like with the new pistons it may be a little small. I've been looking at the MP 284/.484 cam... would that perform well with my combo? Also, I know the intake is pretty old but if I ported it out would it flow well enough to work? Sounds like i've got some things to consider... but if it were you, and you wanted to keep the 190 pistons, would you go for the cam upgrade and worry about the converter and gearing later? Dano-The engine is disassembled, on a stand right now and all the parts listed are parts on hand.
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The cam you have, while small in lift is long in duration and pretty narrow, hence the lope. To me, it looks like a Marine cam. The MP 484 cam (2,600-6,000rpm range), while a dated grind, many have used with success (for decades) and will work (I had the Crane version until it ate a lobe before I even got to drive the car, enter the Lunati I have now). Your intake, even ported is still under sized, it's designed for idle-5500 rpms. It has a small plenum, and longer smaller runners. Great for trucks and mild street engines. You'll need a Stealth or RPM intake at very minimum and better yet a Victor intake. You will still need a stall and more gearing with the MP 484 cam.

I just looked up your head and piston combo, your looking at a range of 10.5 to 11.2 static compression. If the block and/or heads are decked, it will be even higher. Honestly, for a street engine, I'd look into dropping the compression unless you want to run race fuel, even with a large cam.
 
What I recommend is getting everything done far as engine, trans, and gear then call Dynamic (or others) with all your details. Let them custom build you a converter to match everything you have. A good converter is going to cost more than $500 I am afraid to say but it's not a "off the shelf" converter. You will be amazed at the difference from a "off the shelf" converter and a custom built one. So try your best to get everything the way you want it BEFORE you order a converter. You will save yourself a bunch of time and money by thinking out the engine correctly (cam, intake,carb, etc) gears, etc... than backing up and punting all over again later.
 
dustUoff said:
Alright, JoeDust and Dano... thanks a ton for the insight! So the cam that I have was the one that was in the car when I bought it which is why I didn't know much about it till I recently pulled the engine. It definitely had a nice lope to it but sounds like with the new pistons it may be a little small. I've been looking at the MP 284/.484 cam... would that perform well with my combo? Also, I know the intake is pretty old but if I ported it out would it flow well enough to work? Sounds like i've got some things to consider... but if it were you, and you wanted to keep the 190 pistons, would you go for the cam upgrade and worry about the converter and gearing later? Dano-The engine is disassembled, on a stand right now and all the parts listed are parts on hand.
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With the right cam, you should be able to run premium, don't know what the CCs are on those heads, I would talk to Brian on cam selection, I wouldn't run anything lower then 240 @ 50 with enough overlap to keep thinks happy, Those pistons have a .040" quench dome, that'll help reduse the chances of detination. The intake will choke it up, at least get an RPM, or a SD, even an M1 single, The 750 will be fine, At this point with those pistons theres only 1 way to go to take full advantage of the build, otherwise drop in some FT KBs, Brian is a wiz at these SBs, i'll garuantee he can steer you in the right direction, & i'll bet he will pick you a cam that'll work with those pistons/heads on pump premium. Then after you build the engine, you can worry about converter & gears a bit later, because i will tell you from exsperience, That 370 of mine was a monster through & through, I could only amazin how well it would have run at or around Sea level in a 3200 car.
 
Sounds like I should have thought everything out a little better haha! Well since I'm limited on funds, I think I'll call around on a bigger cam to go with my current engine combo. Then possibly see about upgrading my intake... after I get the whole engine squared away then I'll worry about my converter and gearing. Why can't I just be rich and have money to get ALL the parts I want! Well thanks for all the help and I'll definitely keep you guys posted as I put this thing together!
 
dustUoff said:
Sounds like I should have thought everything out a little better haha! Well since I'm limited on funds, I think I'll call around on a bigger cam to go with my current engine combo. Then possibly see about upgrading my intake... after I get the whole engine squared away then I'll worry about my converter and gearing. Why can't I just be rich and have money to get ALL the parts I want! Well thanks for all the help and I'll definitely keep you guys posted as I put this thing together!
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Join the crowd! Anyway, that is your best plan, build the short block and cam accordingly. Aluminum heads will help with detonation, so will having a tighter quench. If your keeping those pistons, you will need to work with an engine builder and your tune will need to be dialed in and monitored, those hypers are not very forgiving to detonation. Plan on an intake, you can sell your Performer to build up some scratch. Do things in order, having a stall sitting on the shelf doesn't get the engine together! So what happened to the 95% driver!!
 
lol... ya well, best laid plans right?? Guess what I WANT and what I SHOULD be building aren't matching up too well! Hey one more question. Is it possible to play with the combustion chambers on the heads a little to try and increase the cc size? If I grind and polish? If I don't touch the quench pad? Or is it too easy to screw something up! Just wondering if I can drop that compression down a tad more so I'm closer to the 10 to 1 CR.
 
My biggest issue with the current cam, it's a REALLY lazy lobe. I wonder at which lobe lift the seat to seat duration was computed. That cam has an intake closing event right at 80* abdc.

The duration at .050 might lend to the detonation monster, the really long ramps will mitigate a bit of that. If it was like a XE268 or 274 with a shorter total duration, then I might be concerned a bit more.

Brian at IMM can definately get you a cam that will work and get one custom cut if needed for a really good price.
 
I'd run a larger dual plane and not a single plane for the shear torque advantage coupled with a pro built converter (AdamR's reply) and 4.30 gears. The purple cam would work fine, though I myself would look at a split duration cam from Comp or Crane with the small valve ported heads. Alot depends on actual head flow balance and percentages between int. & exh. ports. The single pattern cams work best with very well balanced ported head flow between ports, in and out.

Resell the Performer and roll the money over into a new dual plane intake, spend the money on the converter and gear ratio first, cam second.
 
Thanks Rumblefish, got another question for you. If I went with a cam with different durations what should I be looking for? If I had more duration on the exhaust would that help bleed off some of my compression? I was looking at this Comp cam what do you think?
COMP CamsManufacturer's Part Number20-225-4Part TypeCamshaftsProduct LineCOMP Cams Xtreme Energy CamshaftsSummit Racing Part NumberCCA-20-225-4UPC036584047001 Cam StyleHydraulic flat tappetBasic Operating RPM Range2,300-6,500Intake Duration at 050 inch Lift240Exhaust Duration at 050 inch Lift246Duration at 050 inch Lift240 int./246 exh.Advertised Intake Duration284Advertised Exhaust Duration296Advertised Duration284 int./296 exh.Intake Valve Lift with Factory Rocker Arm Ratio0.507 in.Exhaust Valve Lift with Factory Rocker Arm Ratio0.510 in.Valve Lift with Factory Rocker Arm Ratio0.507 int./0.510 exh.Lobe Separation (degrees)110
Also, how much lift can I get away with on stock springs?
 
dustUoff said:
lol... ya well, best laid plans right?? Guess what I WANT and what I SHOULD be building aren't matching up too well! Hey one more question. Is it possible to play with the combustion chambers on the heads a little to try and increase the cc size? If I grind and polish? If I don't touch the quench pad? Or is it too easy to screw something up! Just wondering if I can drop that compression down a tad more so I'm closer to the 10 to 1 CR.
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It would be easier to just change the pistons since the motor isn't assembled. You might be able to have the piston tops milled down too.
 
Well I made it over to Fort Worth this morning to the DFW swap meet and picked myself up an Eddy RPM Airgap intake for a helluva deal! So now i've got something that will hopefully feed this thing air a little better! So my next quest is to get my cam selection figured out so I can get the engine all back together!
 
dustUoff said:
lol... ya well, best laid plans right?? Guess what I WANT and what I SHOULD be building aren't matching up too well! Hey one more question. Is it possible to play with the combustion chambers on the heads a little to try and increase the cc size? If I grind and polish? If I don't touch the quench pad? Or is it too easy to screw something up! Just wondering if I can drop that compression down a tad more so I'm closer to the 10 to 1 CR.
Click to expand...
What head gasket thickness are you running?? A thicker gasket will drop the compression. Be sure to give Brian a call he'll steer you right on your build.
 
crackedback said:
My biggest issue with the current cam, it's a REALLY lazy lobe. I wonder at which lobe lift the seat to seat duration was computed. That cam has an intake closing event right at 80* abdc.

The duration at .050 might lend to the detonation monster, the really long ramps will mitigate a bit of that. If it was like a XE268 or 274 with a shorter total duration, then I might be concerned a bit more.

Brian at IMM can definitely get you a cam that will work and get one custom cut if needed for a really good price.
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I agree. Try the XE268 or XE274.

Yes, the converter will help. But adding one of those cams vs a $400-500 converter... The XE274 cam will make take it to the limit with street tires on the street out of the hole. And will ET lower.

I have a XE274 in a 416 so I'm prejudiced. I think any more would require higher idle speed and get real lumpy on the street. IMHO, it dances on the edge of a hot street cam. Also note I have a 4" stroker 416 that will "soak up cam" compared to a 360.
 
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