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Top end questions
https://slantsix.org/forum/viewtopic.php?t=26920		 Page 1 of 2
Author:  Volare4life [ Tue Jan 29, 2008 4:33 pm ]
Post subject:  Top end questions
Hi there before I get started I have a '79 225 slant six, that will be a daily cruiser, weekend brusier, and a budget right about $1,000. What I want to know what if any performance options there are out there for our beloved leaning tower of power,I am looking at getting a new cam for my slant are there any options out there ?

I found a mopar one online (PN#P4529343) but don't know the specs, anyone know ?

Can I swap a solid cam out for a hydraulic cam ?

Does anyone make a roller cam and lifter set for the slant ?

When dealing with the head, what kind of aftermarket springs are available ?

I heard that SB 340 springs will work, is that true ?

What about valves, should I stay stock or go over size ?

2 piece or 1 ?

stainless or regular steel ?

Do the valve guides need to be replaced with something more sturdier like bronze ?

Should I get the block decked ?

Will it improve performance w/a bigger cam and decked block ?

Will I need new shorter push rods ?

Can I use stock adjustable rockers, NOS rockers, or are there aftermarket one that will fit ?

Obviously decking the block raises the compression, how far can stock internals be pushed ( as far as compression ) before things start breaking ? ( I know it all depends on how much abuse the engine has already suffered)

How do you calculate how much to deck off the block to get the compression ratio you want ?

Will a stock head gasket work for a higher compression engine ?

Are there aftermarket pistons that can be used to raise compression and reduce reciprocating mass ?

"rods"

"crank"

Is there an aftermarket distributor, such as MSD billet, available for the slant ?

I will be using ARP studs, bolts, and nuts through out the engine, MSD 6A Ignition (box, coil, wires)know I have tons of questions, But like my Dad always said "Anything worth doing, is worth doing right the first time !!"

-Mike
Author:  DusterIdiot [ Tue Jan 29, 2008 5:04 pm ]
Post subject:  Need more...
You might research on your options in your area, and are you assembling the engine yourself... If so $1000 is a bit low (I just build a 79 block up and it cost about $1500 but had to leave some stock items in place to cut down cost...)

There are other questions to be asked too, are you using an automatic tranny?(you'll need to rebuild and help it along)... what's your rear end ratio?

You'll need to also express what you are looking for (low 14's in the 1/4 mile... 16's ok but need to keep in the 24 mpg range on the highway?)...

???

-D.Idiot
Author:  Red [ Tue Jan 29, 2008 6:28 pm ]
Post subject: 
P4529343
284/284 duration
76 0'lap
.528" lift
28/32 lash
104 centerline
102 installed centerline
use P3412068 springs (dual/damper)
Author:  runvs_826 [ Tue Jan 29, 2008 7:22 pm ]
Post subject: 
This is what I did on my budget, and a few things I would do different. This is all under the impression that you can assemble the engine correctly.
Larger valves (1.77/1.44) with 340 springs - $175.00
-Not as essential as I thougt, that is your call, but double check that they are not shrouded as that is a complete waste of time and money.
Oregon Cam re-grind cam (270 duration with .44 lift) - $75.00
-get new lifters if your going mechanical, possible use old one's if their clean for hydro. Defintley money well spent, I would increase to .48-.50 lift with same duration.
Port and polish kit for my die grinder - $20 and 8 hours of amatuer port work.
The rest of my money was spent on machine work that included: hot tank, .1 head shave, 3 angle grind, new cam bearings. The engine was already over bored. Spend some time polishing the rods for windage and strength. Get some NOS rocker arms with 1.6 ratio, and you will be rocking. The intake and headers are not included in this estimate so that is up to you. I would think some major power will be put to the ground with this work, and careful going over with the die grinder to the head and block. Good luck!
Author:  Charrlie_S [ Tue Jan 29, 2008 8:09 pm ]
Post subject: 
Quote:
-get new lifters if your going mechanical, possible use old one's if their clean for hydro.
Never use old lifters on a new cam.
Quote:
Get some NOS rocker arms with 1.6 ratio, and you will be rocking.
No such animal. NOS rockers will be about 1.5, you actually need to check many more then 12, and pick the closest ones to 1.5. To get 1.6, requires aftermarket roller rockers (not cheap).
Author:  runvs_826 [ Tue Jan 29, 2008 10:00 pm ]
Post subject: 
I did not know about the rockers! I thought that someone somewhere had the stamped guys at 1.6:1. I don't know if really matters at this pont though.
The lifters comment was straight out of Mopar Muscle. The mechanical lifters are a must. While the hydro guys can go between rebuilds if it's clean, but for the price why bother?
I would browse through the oil system including looking at blueprinting the pump and clean passageways. Also the ingnition has to be looked after, so $1000 dollars is a hard budget to adhere too. Make sure you look at more than kust the engine and cool cams.
Author:  dakight [ Wed Jan 30, 2008 3:29 am ]
Post subject: 
There is no descernable difference in the wear pattern of hydraulic lifters vs. solid lifters. Putting used lifters of any kind on a new flat tappet cam will almost certainly result in lobe failure.

I wouldn't but some do reuse roller lifters because the wear is completely different and there is no seating in required with them. Roller tappet cams are not in common use on a slant anyway.
Author:  Charrlie_S [ Wed Jan 30, 2008 4:33 am ]
Post subject: 
Quote:
The lifters comment was straight out of Mopar Muscle. The mechanical lifters are a must. While the hydro guys can go between rebuilds if it's clean, but for the price why bother?
.
I did not see the article, but I bet they were refering to a Magnum small block. Those engines use hydraulic "roller" lifters from the factory, and it is permissible to reuse them, when swapping cams.
Author:  Volare4life [ Wed Jan 30, 2008 9:48 am ]
Post subject: 
True $1,000 is a small budget, but I can always buy more parts latter on. was mainly concerned about block and head prep.

Now when I install larger valves (1.77/1.44), do I have to get the valve seats cut to fit the new larger valves ?

Do I have to replace the guides ?

Red thanks for the info on the cam, now can I use the cam on a stock engine ?

Will it make any noticable HP gains ?

Should I keep the internals stock, or try aftermarket rods, pistons, lifters ?

Will any aftermarket rockers fit the slant ?

I would like to keep my E/T's low, fuels not really a concern.

I am not sure the rear gear ratio, I swapped out the dinky 7 1/4 for a 8 1/4 out of a '87 5th Ave.

I plan on welding up my own tubular header, and using a clifford 4bbl intake with a 650 holley DP, mechanical secondaries

-Mike
Author:  runvs_826 [ Wed Jan 30, 2008 11:20 am ]
Post subject: 
The stock internals were a concern of mine for my next build also. However everything I've read says they stay together just fine under relative extreme horsepower. Forged pistons are a possibilty if you plan to run nitrous, otherwise I would get some standard overbores and call it good. The money there I would suggest in getting your rotating assembly balanced which is the real money I would put into my bottom end. Also decking the head .1 was the BEST MONEY SPENT, as it kicked up the compression enough. Get some play-dough and see if your hitting your pistons because of the big cam.
There is only the Cox. Bros roller rockers availble, someone else was working on getting some from T&D. Once again you are going to be running into your budget concern being as I've seen the average set go for an upwards of $4XX. This hasn't ever seemed to be an area of need for the slant, even Slantzilla suggests not using them. Cox. Bros also have a roller cam for the slant (I've heard, never verified with them), however, the cam you have should be more than enough. Defintley install bronze giuds, seats, and new cut for the valve. This is the place to spend the money.
The money spent on the hi-pro parts the v8 guys use seem to be better spent on the more basic tricks for the slant. Rotating the assembly and every port and polish get skipped now since they can buy Dart heads and H-beam rods. Not to say they son't do impressive feats, but for us you can spend half the money and obtain even results. In fact Indy this year in their competition used Magnum heads instead of their high dollar ones to achieve their 59X hp number, so sometimes the aftermarket can be overlooked for better OEM components. I've learned off of 302's that were primarily stock parts remachines to provide a monster of an engine.
Thanks to Charrlie_S for the corrections, it's good to have someone looking over your shoulder, even if your wrong.
Author:  Volare4life [ Sat Feb 02, 2008 5:24 am ]
Post subject: 
So stock crank, rods, forged pistons.

But If I switch to aftermarket pistons, from the 2.2/2.5 will I need longer rods to make up for the shorter piston ?

Will they need to be raised dome or dished ?

I would like to be shooting for 9:1-9.5:1 CR

I saw Comp make small cams 252/252, I lost the acution for the 284/284 MP Cam so I'm trying to find an alternative that will suck and expel some serious air.

Can I use stock keepers ?

Valve spring hats ?

" " Valve stem seal ?

Will the spring pads have to be cut to fit the new dual springs ?
-Mike
Author:  slantzilla [ Sat Feb 02, 2008 7:01 am ]
Post subject: 
Before you do anything, what trans, converter, gear, and car weight are you working with?

A 904 with a stock converter, low rear end gears, and heavy car will equal a pig if you don't build a motor to fit.

Personally, I like to build the rest of the drivetrain before the engine.

A car with a stock motor, good converter and gear will always outrun a car with a hot motor, stock converter and low (numerical) gears.

:shock:

If it makes you feel any better, I've been running low 12's for a long time with 1.71/1.50 valves and stock rockers. :twisted:
Author:  Bren67Cuda904 [ Sat Feb 02, 2008 8:01 am ]
Post subject: 
Like Zilla said we need to know what your car is and its intended use. Be realalistic. Your not going to be running 13's or 14's on a $1000 budget. (on motor)
Let us know what you've got now and where you'd like to go.
Car/weight?
engine? Carb? manifolds? Ect?
converter? stock?
trans?
rear gear?
tire size?
A/C or not? :lol:
1/4 mile or 1/8 tracks?
Highway use? How much? Be real here.
Daily driver?


Above all don't ask ME how to build one cheap. All I know how to do is spend money. :lol:
Author:  Volare4life [ Tue Feb 12, 2008 9:51 am ]
Post subject: 
1979 Plymouth Volare/3,600#'s

blown(hole in block from rod/piston) 225, stock carter 2bbl, stock cast manifold (EGR system removed)--IN process of getting another '79 225

Automatic 727/stock lock up converter

not sure the rear gear came out of a '87 5th ave, possible 2.76's ?

front tires 215/55R15 on 15X6 steelies/rear 255/65 R15 on aluminium 15X8 mags (think dukes of hazzard mags)

No ac

1/4miles daily driver, high way daily


What I will be doing is stripping the interior and just having 2 light weight racing approved buckets, roll cage if she can go fast enough ;), Hurst mega shifter, shift kit, Linelock, light weight Weldlite wheels, nitto drag radials


Now since I have a 727 for the slant will any and all 727 parts ie shift kits, trans brakes, torque converters fit ? How high of stall should I go ? should I go for a tighter 9" converter ?

Like I said the $1,000 is just the initial cash for the main (big expensive) stuff ie block tanking and machining. But I keep adding $75-100 a week @ $1,300 right now. Just need some guidance and direction on this build,


Thanks,
-Mike
Author:  runvs_826 [ Tue Feb 12, 2008 10:49 am ]
Post subject: 
Well, to start with 1/4 mile car and daily highway are probably the worst combination you could think of, but hey it's ok we can work around that. The rear gears will be a personal choice of yours, 3.23 seems to be you best choice with the 727. I have an A833od so I could go with a little higher, but like I said before it's personal, which are you going to do more? This would be a better starting place like metioned before if the car is down. Maybe even a trac-bar if you want, no cheap ladders that everyone can see that's a personal peeve of mine.
A 14 sec car is plausible but make sure you do realise it will probably be 14.8 not much lower. Gerg Ondayko (spelling?) runs about that and has street trim, runs a four speed, and believe he hasn't done anything extremely radical. So write out your goals with the two ideas metioned above. Sometimes I don't have a hp or time in my build but an idea of what I want to do and I'll just see what happens.
There is a thread on Matrix Builds that has some good recipes. The head would be a good starting place for the money you got right now. Shave the head .1, 3 angle, bronze guides you know the drill. On ebay there is a great guy (in my opinion) who sells valves that drop right in. 340 springs from your local NAPA. As soon as you hot tank the head spend some time cleaning it up with the die grinder. I would do what I could do and than hand it over to the pros whatever that limit would be.
2.2L pistons I don't think match up with stock rods. The "long rod" is .3in so something to measure off. Arias makes some stock forged pistons, and for a daily driver I wouldn't go over 60, I believe the 2.2L's bore is 3.5. Make sure to get the bottom end balanced, there is some different ways to prep your bottom end including shot peening and reducing windage.
Camshaft will be important. With this build you could most likely go with .5 lift and 270 duration. Talk to your local cam grinder, OregonCam did a great job for me for example.
Intake will be interesting, I have no idea what the 2 barrel is truly capable of since it didn't impress me. There is lot's of places to get offy four barrel including a NIB I have.
Even with all this machine and parts I don't believe you'll be more than 1800 complete engine. The local 340 if 1400 for an incomplete engine with 30 over. That leaves tranny prep and rear end. Good luck.
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