Critique my mismatched Teen Build.

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Teedog

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Mt Gambier SA
Heya Guys.. and Gals of course.

Below are the specs of the 318 I am building.
No.. I'm not building a 360.

What sort of HP figure and performance do you think I might achieve with this perhaps somewhat mismatched set of parts I have gathered. This is my first ever build and yes I realize that I have already made some mistakes here but the parts are purchased/money is spent and I don't think the engine itself will be that 'terrible'. Hopefully.


1976 LA 318 Block bored 0.020" over to 321 cubic inches.
KB167 Hyper pistons. Block Zero decked.
Stock Cast crank linished/polished, Resized stock rods.
Entire rotating assembly balanced.
Edelbrock Performer RPM heads #60779, surface milled to 61cc chambers.
Yes.. these heads are too big!!
With a 0.038" head gasket I will only have SCR of 9.85 / DCR of 8.25
Yes.. I should have another point of Compression here!!
Hughes Engines Roller Rockers 1.50 ratio.
Comp Cams Xtreme Energy 'Xe262' Hydraulic Camshaft with matching lifters.
New Milodon Sump and Windage Tray.
Standard Volume Oil Pump.
Weiand Stealth Dual Plane Intake #8022.
Edelbrock Thunder Series AVS Carb - 650cfm #1806
Aussie Pacemaker Tri-Y design Headers, 1 5/8" primaries, 1 3/4" secondaries, 2 1/2 outlets.
2 1/2" Dual exhaust with X-pipe crossover.

This engine will be going into a 3000 pound vehicle with a 904 Auto.
I also have a Trans-go shift kit for the Auto, yet to be installed.

I am trying to achieve a Peppy Performing Street Car /Cruiser with at least 320 flywheel HP. The car is not a daily driver and will most likely only be a weekend Sunny day machine. This car would rarely get to a Drag Strip although future upgrades not ruled out.

Major issues that remain are that I believe I currently only have a stock stall converter and this will need to be bumped up... , and my Stock standard fragile 7 1/4 factory Borg Warner diff which at this point has really long legs also, 2.92 Ratio. Hehe, yes I know, I know. Yet to sort out what I'm going to do with the diff, at a minimum I will throw in some 3.23 gears.

I was also tossing up going to an 'off the shelf' solid cam but not sure what my options are with this... most solid flat tappets are huge for the performance level I'm chasing.
(and the rest of my current drivetrain)
Maybe a Solid Comp 270s or the larger xe268s but even that looks too big for this little Teen.

At this point until I upgrade the converter and diff I feel my current xe262 cam may be at my limit perhaps.

Thanks guys..
What are your thoughts guys?

Cheers,
Teedog


P.S Yes I know my heads are too big!
 
Find a 8.25 rear, you'll be better off than dumping a single penny/cent/or what AUS money is called (sorry dont know it off hand). I'm guess 330 hp or so.
 
I like the build. Heads are not "too big". Needs more cam, IMO, but that one will work fine and achieve your power goals, I believe.
 
I think you will be well past 320 HP. Maybe 330-340 as a guess... before even looking at the above posts by 1970 Duster and RRR. (I am just adjusting HP from a 340 with similar heads and CR and a step larger cam and 1.6 rockers.) It should well meet your goal of being a peppy street cruiser.

IMO the heads are fine for a street cruiser.... and will make HP. The cam will control most of what will happen anyway and the breathing of the heads will help all around, even with lower lift. Your CR will be good to widen the torque range. Approach full throttle with caution! Let us know when you get that first speeding ticket or blow the rear, whichever comes first!

And mismatched? Not hardly.....I've built and run a small block Ford with similar breathing, single plane intake and larger header pipes, and a high lift cam with much lower duration and it was a great street motor. Veeeery wide RPM range and well matched to a stock converter; the cam made it so despite the big breathing parts.
 
I am trying to achieve a Peppy Performing Street Car /Cruiser with at least 320 flywheel HP. The car is not a daily driver and will most likely only be a weekend Sunny day machine.

Thanks guys..
What are your thoughts guys?

Cheers,
Teedog


P.S Yes I know my heads are too big!



Probably 300-320 HP but only if you get the airflow to match.

You will lose efficiency in a big way if you don't get the engine airflow balanced. Intake, heads, compression, exhaust and carb all need to work together or they are fighting each other...resulting in a loss of power.

Better to build a tight smaller set-up that a mismatched bigger one.
 
Just put together a similar combo, stocky eddy heads on a 318. Rering on replacement pistons 10 thou below deck. Round about 9:1 comp. With a lunati voodoo 213/220 @.050
Has stock 2.92 diff and stock converter. Makes loads of low down torque and converter flashes up nicely. Idles with 14 " of vac. Those diffs can take a good bit of abuse before they break an axle. Lots of those diffs running 9's. Makes good power probs 320 hp should run a 13. Will be changing to 3.5 gears soon but leaving stock converter.
 
Thanks all.
All comments, advice and criticism much appreciated. As I said, first build so am still learning.

It looks like my HP estimate figure seems to be around the mark then.. that's great.
So if i was to move up to an Xe268 hydraulic or equivalent, there would be perhaps another 20-25 HP available to me maybe. Similar torque though?

At this level, is there any gain whatsoever by switching to a solid cam for what is really a Street Car? Personal preference only perhaps?
I'm guessing any gains would be at the very upper end of the Rpm range only?


Cheers,
Teedog
 
A properly sized solid cam will actually excel in low end,mid range,and top end over a hydraulic cam.I wouldn't consider it a worthwhile expense in your situation...yet.

Sounds like a well matched combo that should perform well.The rear end will live until it hooks hard.

The xe268 will make more upper rpm power at the expense of some low end in a 318 IMO.
 
A properly sized solid cam will actually excel in low end,mid range,and top end over a hydraulic cam.I wouldn't consider it a worthwhile expense in your situation...yet.

Sounds like a well matched combo that should perform well.The rear end will live until it hooks hard.

The xe268 will make more upper rpm power at the expense of some low end in a 318 IMO.

So having said that, how would the Solid Xs268s compare to the Hydraulic Xe268 at the lower end of the Rpm range? Or the low lift 270s?

Cheers,
Teedog
 
Our diffs in our Aussie mopars arent what were in US mopars. We had locally manufactured diffs. Lots of our stock type diffs running 9's with a spool and billet axles

come on now!! nobody is run'n 9's with a 7 1/4. the torque of a 9 sec ride would twist the yoke off. not to mention the carnage of the internals from a dead hook.
 
As much as I deplore that recommendation because it is entirely over used, yeah, that's kinda what I was thinkin.

You wouldn't consider a solid cam worth trying with similar or slightly higher specs seeing that I already have the adjustable rocker gear?

Cheers,
Teedog
 
You wouldn't consider a solid cam worth trying with similar or slightly higher specs seeing that I already have the adjustable rocker gear?

Cheers,
Teedog

Absolutely I would. I generally used to make that recommendation, but all these wussies around here always cry about the added expense and the "trouble" of having to periodically adjusting the valves.

You are correct though, the small solid will make more power completely across the board. Both down low, in the middle and up high. The Comp 274S would be an excellent choice just for an off the shelf grind.

You have to keep in mind, a solid cam will "act" like a hydraulic cam that has about ten degrees less duration, so the 274 is right on the money.
 
Rob is spot on, take his advice into count, he knows his stuff.
 
You wouldn't consider a solid cam worth trying with similar or slightly higher specs seeing that I already have the adjustable rocker gear?

Absolutely I would. I generally used to make that recommendation, but all these wussies around here always cry about the added expense and the "trouble" of having to periodically adjusting the valves.

You are correct though, the small solid will make more power completely across the board. Both down low, in the middle and up high. The Comp 274S would be an excellent choice just for an off the shelf grind.

You have to keep in mind, a solid cam will "act" like a hydraulic cam that has about ten degrees less duration, so the 274 is right on the money.

Ok.. so I would certainly be happy to look into stepping up to a solid cam and lifters however my question would now be this...
Would the Edelbrock 'Sure Seat' Valve Springs #5767 as are currently on the heads, be usable on any of the following camshafts?

Comp 270s - I suspect this one would work as Comp specifies the 901-16 Spring which I think the Eddy spring exceeds, although they do not list a spring rate as such?
(This is a small solid but I suspect it would probably still out perform the Xe262 hydraulic and still run with a stock converter.)

and the Comp Xs268s and Xs274s - Not sure the Eddy springs could control these cams?
So I would also be up for new springs, retainers, locks etc.

Eddy Spring #5767 120lbs on the seat 310lbs open (0.580" lift) and as I said no spring rate stated.

How many are running the stock springs on the Eddy #60779 Heads?
Guessing not too many.


Cheers,
Teedog
 
When it comes to people saying don't run large port heads, I believe that's trickle down from engines like the tunnel port 302's and such. 273 heads where designed for a 273 and 340 heads where designed for a 340, 318 and 360 didn't have any heads designed for them until the magnum and when 318 was built the only head being produced was the 273 which is fine for a low powered 318. But 318's are closer in size especially when over bored to a 340 than a 273.

I was thinking the same head and cam combo if I go 318.
While your cam choice leaves power on the table it all depends what your after. For my 400 ford I picked a small cam comps 255deh cause with headers, performer intake and carb, bowel work and that cam I'd figured it would double the stock power output which is more than enough for the bronco and I know I could easily go bigger but I'm not willing to give up even a 1/2 mpg for even 20 or more hp. But for your build I would go with the solid cam a 318 with those heads will love rpm and smaller engines hp curve tapper off slower than larger engine giving you more of a usable powerband (rpm).
 
Ok.. so I would certainly be happy to look into stepping up to a solid cam and lifters however my question would now be this...
Would the Edelbrock 'Sure Seat' Valve Springs #5767 as are currently on the heads, be usable on any of the following camshafts?

Comp 270s - I suspect this one would work as Comp specifies the 901-16 Spring which I think the Eddy spring exceeds, although they do not list a spring rate as such?
(This is a small solid but I suspect it would probably still out perform the Xe262 hydraulic and still run with a stock converter.)

and the Comp Xs268s and Xs274s - Not sure the Eddy springs could control these cams?
So I would also be up for new springs, retainers, locks etc.

Eddy Spring #5767 120lbs on the seat 310lbs open (0.580" lift) and as I said no spring rate stated.

How many are running the stock springs on the Eddy #60779 Heads?
Guessing not too many.


Cheers,
Teedog
Teedog i run the 268 solid in my 318 but i run the EQ magnums heads 1.6 rollers very nice cam idles @ 750 in gear with some lope very strong mid to top end power ,you will need to run min 3.55 rear end and a min 2500 stall, not the **** off the shelfs but one made for your combo,get your dizzy curved.everything got to match to make it work right.Listen to rusty he know his stuff.
 
Heya Guys.. and Gals of course.

Below are the specs of the 318 I am building.
No.. I'm not building a 360.

What sort of HP figure and performance do you think I might achieve with this perhaps somewhat mismatched set of parts I have gathered. This is my first ever build and yes I realize that I have already made some mistakes here but the parts are purchased/money is spent and I don't think the engine itself will be that 'terrible'. Hopefully.


1976 LA 318 Block bored 0.020" over to 321 cubic inches.
KB167 Hyper pistons. Block Zero decked.
Stock Cast crank linished/polished, Resized stock rods.
Entire rotating assembly balanced.
Edelbrock Performer RPM heads #60779, surface milled to 61cc chambers.
Yes.. these heads are too big!!
With a 0.038" head gasket I will only have SCR of 9.85 / DCR of 8.25
Yes.. I should have another point of Compression here!!
Hughes Engines Roller Rockers 1.50 ratio.
Comp Cams Xtreme Energy 'Xe262' Hydraulic Camshaft with matching lifters.
New Milodon Sump and Windage Tray.
Standard Volume Oil Pump.
Weiand Stealth Dual Plane Intake #8022.
Edelbrock Thunder Series AVS Carb - 650cfm #1806
Aussie Pacemaker Tri-Y design Headers, 1 5/8" primaries, 1 3/4" secondaries, 2 1/2 outlets.
2 1/2" Dual exhaust with X-pipe crossover.

This engine will be going into a 3000 pound vehicle with a 904 Auto.
I also have a Trans-go shift kit for the Auto, yet to be installed.

I am trying to achieve a Peppy Performing Street Car /Cruiser with at least 320 flywheel HP. The car is not a daily driver and will most likely only be a weekend Sunny day machine. This car would rarely get to a Drag Strip although future upgrades not ruled out.

Major issues that remain are that I believe I currently only have a stock stall converter and this will need to be bumped up... , and my Stock standard fragile 7 1/4 factory Borg Warner diff which at this point has really long legs also, 2.92 Ratio. Hehe, yes I know, I know. Yet to sort out what I'm going to do with the diff, at a minimum I will throw in some 3.23 gears.

I was also tossing up going to an 'off the shelf' solid cam but not sure what my options are with this... most solid flat tappets are huge for the performance level I'm chasing.
(and the rest of my current drivetrain)
Maybe a Solid Comp 270s or the larger xe268s but even that looks too big for this little Teen.

At this point until I upgrade the converter and diff I feel my current xe262 cam may be at my limit perhaps.

Thanks guys..
What are your thoughts guys?

Cheers,
Teedog


P.S Yes I know my heads are too big!


I'm late do this party and have this to say

Your heads are not to big
Your cam is to small
You do not need more compression
I'd run at the very least the XE268
I'd run a min. of 3.55's
I'm not sure of your headers, but a tri-y will do fine with that combo I described.
 
Engine recipe looks good. Think twice about going bigger on the cam. Big cams like big compression. Go too far and throttle response drops off. Comp Cams has selection free software available. http://www.compcams.com

Agree with recommendation for dumping the 7¼ axle and its 2.92 ratio. If you are unable to find a Mopar 8¼ or 8.75, suggest looking at first and second generation (1960-72, Australian) Falcons for a 9" or maybe an 8.8". The spring perch width should be the same as your A-body. The five-bolt wheel axles match BBP Mopar. Suggest a 3.55:1 ratio with a locking diff.
 
If its only a car you drive every once and a while I would definitely put in more gear especially if you are going with a bigger cam. Adding 4.10s was the best upgrade I ever did to my dart! Id go with at least 3.55s. Thats just my opinion though, I dont mind if I run more rpms on the highway.
 
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