Edelbrock / RHS heads, or go BIG block and put it to bed!

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WOW! Took awhile for that answer to pop up. i'll say it again after Dodge freak did. No! 17,000 aint crap for a head change.
 
pilotsf said:
Thanks for the break down. Your right, I have a solid car just needs tweaking. One more thing, is 17,000 mile on the motor to high do do a head job. I would hate to start chasing motor repairs.
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No 17,000 miles isn't too high do do a head swap. Their really isn't a set number. You can swap heads whenever you want, some consider it kinda pointless if your dealing with a 100,000+ mile motor because the bottom end is still worn out or close too it, but if the motor has good compression in all the cylinders why not.
 
pilotsf said:
Thanks!
You have helped me before. Small block it is. Its cheaper and easier. Im concerned that a few have said Im down on power as it is now(mean somethings wrong?). Edelbrock said since i have the eddy manifold and carb we should be good to go with mild porting. Can you give me the complete info for Brian and IMM ? RHS is also cheaper!
One more big question i'm at 17,000 miles after the 2 year build. Is it still worth it to do or to late. motor runs strong.
Thanks again
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I just did a set of eddy heads, 2.02 valve, heavy porting, and they go 275cfm at .500 and 283cfm at .550 and then quit flowing more air. That cost 850.00 with valve job...a bit more flow than the RHS but not enough to warrant the cost IMO.
Brian
 
It's apples and oranges when talking aluminum or iron heads. Do you know the chamber size of the heads you have now? How deep are the pistons in the block? If you really have 9.5:1 compression, you NEED iron heads. Or go with Eddys an a set of pistons at zero deck. Either way, they're closed chamber heads an must have proper quench to perform well.
 
pilotsf said:
heads were done at the motor builder. im sure not a real pro job. done with a hand polisher. no flow test. whats a leak down test? I bet if i put edelbrock heads on the motor would bring it back up to where it should be?
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A leakdown test is similar to a compression test, but it tells you how much pressure is being lost past rings or valves. It's more of a performance compression test...lol. The reason I bring that up is the math is telling me what you have now is not producing what it should. IMO, adding any new parts without addressing that issue, might take care of it (if you replace the right stuff) or might do nothing (if you don't).

You have a car that weighs (estimated by me) around 3200lbs. If it's actually heavier, you're making a little more power. If it's lighter, it's making less. You reach 100mph. With my estimate that calculates about 250hp to the tires, or around 300 at the crank. Your dyno confirmed it's close to that. There's always some error in figures such as these so don't start looking for the difference between them...lol. Just understand that it's low for what you have for parts. What I think might be the case, is the lower end is not blueprinted and the static compression is lower, and/or the heads have problems, and/or the cam or installtion has problems, and/or the tuning is off. But, I would anticipate if the engine had ported heads (assuming mild and average quality) and a 280/.480 hydraulic cam, with 9.5:1 and the parts you mention, that you would have closer to 375-390hp and be running closer to 107 in the 1/4. Which is high 12s and what I would expect to see a 360 A body running.

Now, if you are dead set on heads and the leakdown shows no ring seal problems: IMO, you should pull a cylinder head first looking for what you have for pistons, piston installed height (how far down in the bore they are), and valve reliefs. If the compression is really 9.5:1 now, then adding the closed chamber heads will add about .8 to the compression ratio. Depending on the pistons and how it was put together you may need to be careful with the cam choice. If you go with aluminums, you have to use the right gasket and it's thicker than the MP thin ones that would work with iron. So again, to get everything from it, you need to get what you already have on paper nad then come up with a plan. $2500 will get the job done with RPMs too so budget's not really an issue at this point.
 
ou812 said:
I just did a set of eddy heads, 2.02 valve, heavy porting, and they go 275cfm at .500 and 283cfm at .550 and then quit flowing more air. That cost 850.00 with valve job...a bit more flow than the RHS but not enough to warrant the cost IMO.
Brian
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(I'm going to have to send you my Edel. Heads one day....)

Brians post is what I often refur to and mostly in the highlighted bold. If your engine isn't really more than a mild hop up over stock, the Edel. heads are not really worth the money invested. While IMO, the head (Edelbrock) is a good head for street and light strip, the expense vs performance return on a mild mill is not what I would call a big bang for the buck.

In this area, I suggest ethier porting the OE head or going to a brand new head in which these days IMO, would be the Indy/RHS head. Alot depends on exactly what your doing, where you wanna go with it and what is allready done to the engine.

Looking at your basic build info, it is not much more than a stock set up with a few extra goodies on top. This type of build was very common in the old days on top of stock short blocks. Your cam timing and lift are still on the small side. Though it will for surely make good power, it is still a streetable 100% of the time combonation of parts.

To really take advantage of the Edelbrock head, (OOTB adv. flow rates at least) I would be looking at least another 10* of duration and .550 lift at a min. amount. (In which actual at the valve lift will be slightly less than .550.)
 
rumblefish360 said:
(I'm going to have to send you my Edel. Heads one day....)

Brians post is what I often refur to and mostly in the highlighted bold. If your engine isn't really more than a mild hop up over stock, the Edel. heads are not really worth the money invested. While IMO, the head (Edelbrock) is a good head for street and light strip, the expense vs performance return on a mild mill is not what I would call a big bang for the buck.

In this area, I suggest ethier porting the OE head or going to a brand new head in which these days IMO, would be the Indy/RHS head. Alot depends on exactly what your doing, where you wanna go with it and what is allready done to the engine.

Looking at your basic build info, it is not much more than a stock set up with a few extra goodies on top. This type of build was very common in the old days on top of stock short blocks. Your cam timing and lift are still on the small side. Though it will for surely make good power, it is still a streetable 100% of the time combonation of parts.

To really take advantage of the Edelbrock head, (OOTB adv. flow rates at least) I would be looking at least another 10* of duration and .550 lift at a min. amount. (In which actual at the valve lift will be slightly less than .550.)
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Thank you everyone for your help! As always I know what to do now. RHS HEADS and Run it !
 
moper said:
.....Just understand that it's low for what you have for parts. What I think might be the case, is the lower end is not blueprinted and the static compression is lower, and/or the heads have problems, and/or the cam or installtion has problems, and/or the tuning is off. But, I would anticipate if the engine had ported heads (assuming mild and average quality) and a 280/.480 hydraulic cam, with 9.5:1 and the parts you mention, that you would have closer to 375-390hp and be running closer to 107 in the 1/4. Which is high 12s and what I would expect to see a 360 A body running.

....
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Could working on the chassis, converter, and engine tuning possibly get him in the 12's? Is the Edelbrock carb ok or costing HP?

Like would knowing his 60' times help to know if he is hooking up?? I don't think he's listed those times.
 
pilotsf said:
thanks.
my average 60' times were 1.93 with slicks. i was going to put 4.11 gears in the rear for quicker times but i would like to get 300 hp to the wheels, and up my trq. Im just trying to tweak the car a bit for a good drivable street car.
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While the Edelbrock carb isn't my choice carb for racing, the carb style seems to cost some top end power or speed. I find the carb very very good for street use and also find it capable. It's best quality is tunability on the primary side.
It's worst quality is un-tunabilty on the secondary side.
Lack of air bleed chanabilty is an issue with the carb sitting on a big cam and etc.... mods on a very serious engine.

(Perfur a AVS style myself for secondary opening changes over the counter weighted air door on the AFB.)

Personaly, more gear & converter would help a good bit. Alot of info reguarding this is not posted. Frames tied togther would be nice.
 
With a 68 Dart like yours, I would think for a while about a big block. Yes, it costs some cash.

If you REALLY would be satisfied with a high 12 second quarter, it should not be hard to reach with your 360. If, a year from now, you wish you were running high 11's... see what I'm getting at? Figure out what you're really after and don't build the car a third time.

I happen to like the Edelbrock heads. They'll let you run a bit more compression and squeak by with premium pump gas. That would mean some machine work, or a piston swap, and I assume that's not in the plans.

I dig the AFB for a mildly built engine.
 
He really needs to get rid of the taxi cab carb... it's probably a good 15hp behind a similar sized holley. I'm not a fan of those Ede carbs, period.

No reason with good tuning, a really good converter and tweaking, that car can't run 12.5's as it sits before any head change. Just takes time and finding out where the time is going. I'll guess the converter isn't the best piece, change that and the carb and it's an entirely different animal.
 
Put an 850 Holley DP on it!

The Edel is better for idle quality but the 850 DP would out do it. Plus it kick in faster...yep more converter and an 850 holley would make a noticeable difference. It be cheaper too.

You could use both carbs, use the holley just for the strip--if you take it there. The Eddy is a great street carb, IMO...but then I run two 500 cfm eddies.
 
I agree there's something (or somethings) that could yield solid improvements without major component replacement. But I'd like to see how it goes after the swap.
 
dodge freak said:
Put an 850 Holley DP on it!
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Screw that. Put a Holley 1050 Dom. on it. Crap, if your going bigger than big since the 800 is allready a bit big, ya might as well go to a Dom. F%^&( it, Right?

In fact, your idea of twin carbs is great. Twin Dom.'s on a T-ram, FG$%^& IT!
 
I would highly recommend a holley 750DP carb...it makes more avg. power and better peaks as well.
The RHS heads will get you where you want to be, the carb can be added later.

I always suggest guys work work work that chassis! We race cars not engines, so the better the chassis (launch) the better the car will e.t. with the same power.
My car is a perfect example. Even with only 460 or so HP it ran 6.94 in the 1/8 at 3350lbs. with a 1.42 60ft. That was with a 3500stall Hughes converter and foot braking too.

It did make alot of TQ though...the 60ft. made that e.t. SHINE!!
Brian
 
750 DP would be the best all around carb and you might find a good buy off ebay.

You could just swap carbs first. Look in to tossing some stuff away to lose weight. If the car came with AC and it no longer has it, by the heater core is some unneeded parts, only like 15 lbs but it all adds up.......................we used to remove the seat belts, carpet, padding to loose weight back when I went to high school, ah the good old days, lol
 
You have everything you need in the engine to go in the 12 second range.
Your mph is very good for the cars ET.

Your 60 foot times are way off.
Remember that 1 tenth of a second in 60 foot is worth 2 tenths on the end of the track.
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If I had to guess I would say the car is very slow off the line and getting good traction OR spinning it's wheels.

Knowing the answer to this question would help?????(spinning or hooking)

Also...What is your stall speed and gear ratio??????????

And where did your engine make it's peak torque on the dyno????


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A) If it's spinning then adjust the pinion snubber 1/2 inch from the floor and keep the tire pressure as hard as possible without spinning ,plus make sure that a good burnout was performed.

B)If it's hooking good then it's the carb that needs adjusting.

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Having a good TORQUE CONVERTER BASED ON THE DYNO INFORMATION would help you out the most in the sixty foot.

You have enough power to go 12's.

Make it hook and keep the engine in it's max power band and your there.

Installing a set of heads next is the ticket.

I would change the cam last.
 
T67POWER said:
You have everything you need in the engine to go in the 12 second range.
Your mph is very good for the cars ET.

Your 60 foot times are way off.
Remember that 1 tenth of a second in 60 foot is worth 2 tenths on the end of the track.
---------------------------------------------------------------------------
If I had to guess I would say the car is very slow off the line and getting good traction OR spinning it's wheels.

Knowing the answer to this question would help?????(spinning or hooking)

Also...What is your stall speed and gear ratio??????????

And where did your engine make it's peak torque on the dyno????


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A) If it's spinning then adjust the pinion snubber 1/2 inch from the floor and keep the tire pressure as hard as possible without spinning ,plus make sure that a good burnout was performed.

B)If it's hooking good then it's the carb that needs adjusting.

________________________________________________________________

Having a good TORQUE CONVERTER BASED ON THE DYNO INFORMATION would help you out the most in the sixty foot.

You have enough power to go 12's.

Make it hook and keep the engine in it's max power band and your there.

Installing a set of heads next is the ticket.

I would change the cam last.
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Thanks! You have helped me before too. Awsome
Its hard to keep my car a good driver and a good racer but that is my main goal. I want a 1968 flash back.

A-I just purchased some dot 28" dot street drag slicks to help launch.
B-I'm for sure going to a smaller 750 carb(during head change)
C-Buying heads on Monday and shipping to motor builder.
D-Problem? Eddy or RHS heads? Eddys are 1600$ ready to go and RHS from IMM are 1350$ ready to go. My engine builder STEVE WANN(race champion hemi bracket) is going to have to decide. I cant !
E-Removing any extra weight
C-Converter
F-3.73 gears now, probably will go to 4.11 with a locker
What do you think! you have always helped and I appriciate that.
 
What converter stall speed do you have and at what rpm did the engine make peak torque at????
 
Pioltsf, What RPM are you crossing the finish line at with your current 3.73 gears?

And you just purchased 28" dot tires, what was the diameter of your other tires?
 
pilotsf said:
D-Problem? Eddy or RHS heads? Eddys are 1600$ ready to go and RHS from IMM are 1350$ ready to go. My engine builder STEVE WANN(race champion hemi bracket) is going to have to decide. I cant !
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Those eddys wont make near as much power as the rhs's, unless he does some serious porting to them. Is $1600 for the eddies with any of the correction machine work that's required to fix the guides and crappy valve job, or just OOTB. If OOTB, those eddies are not that good. Better than a factory X/J head, yes, better than Brians RHS set up, no fricken way!

Ede's go about 215 cfm at .400 lift which is what you will be accessing, the rhs go somewhere in the 240's at .400. There's some good power to be gained there, better chamber... and the RHS are not ported one bit.
 
Plus iron heads hold the heat in better and make more power over the same ported aluminum heads. Now if the compression was 11 to 1, aluminum heads would run on pump gas were the iron heads would need better fuel.

With just 9.5 to 1 compression, stay with iron heads, IMO
 
crackedback said:
Those eddys wont make near as much power as the rhs's, unless he does some serious porting to them. Is $1600 for the eddies with any of the correction machine work that's required to fix the guides and crappy valve job, or just OOTB. If OOTB, those eddies are not that good. Better than a factory X/J head, yes, better than Brians RHS set up, no fricken way!

Ede's go about 215 cfm at .400 lift which is what you will be accessing, the rhs go somewhere in the 240's at .400. There's some good power to be gained there, better chamber... and the RHS are not ported one bit.
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Bull puckies! lol
I run OOTB RPMs with valve jobs corrected and gasket matched on my strokers and they make 450-490hp depending on the combo. That's about 240-245 on a street cammed engine (.497 @ the retainer) by the numbers. And that's more than one set of them over years. So I can't agree with that.
That being said - The comparison is not apples to apples. The RHS are ready to bolt on for $1350+S7H from Brian. They are purchased as bare castings so if you buy them, your shop may get more for the work or get worse results. RPMs come assembled but IMO are not in any condition to be run OOTB. They need the valve job fixed, special head bolts, the special Fel Pro head gaskets, and possibly upgraded springs which brings the cost to get them on the engine and running up to around $2K plus springs. RPMs are lighter and have more potential than the RHS heads. But that costs.
In this particular instance, I think Brain's heads are the better choice. Again assuming the engine is healthy and the issues it has are tuning/setup. I still don't believe it is but that's of no consequence.
 
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