Another aluminum head comparison
Thread Starter
Instructor
Joined: Apr 2018
Posts: 165
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From: Buxton ME
Another aluminum head comparison
I've read some past posts on the preferred aluminum heads for the C3 350's, but I have a question based on latest pricing. I'm trying to decide between the Summit Racing head and the highly-recommended Trick Flow DH-175 head. I found some older dyno tests that say the Summit heads are middle of the pack, but the range is usually is 10 or 12 hp, which I probably won't feel on the street. The cost difference is $1,134 / pair for the Summits versus $1,630 / pair for the Trick Flows. The $500 difference would cover the cost of the cam kit and most of the associated gaskets, studs, etc. Would pair with a Lunati Voodoo 703 cam (227/233 @ .050").
Latest thoughts?
Latest thoughts?
NCM Grand Opening Veteran
Joined: Sep 2005
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From: South of giving a damn
St. Jude Donor '11, '17
Horse power costs money, how much HP do you need? Sounds like you are more than willing to give up a few ponies for a little value. I have no issues with that idea and I like your plan to save some cash on the heads to finance the cam kit.. I have no idea on the cam, but I'm sure others will chime in.
Race Director
Joined: Mar 2016
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From: Napa Valley California
You need to match the head specs to your engine build to see which heads will perform best with the compression ratio, camshaft and where you want to build power.
Do you want the engine to make more power in the low to mid rpm range, or do you want it to make more power on the top rpm range?
What are your total end plans for the engine and what are you going to use the car for?
The wrong head and cam choice to save a few bucks could make the engine a real dog and not perform where and how you want it to.
Are you going flat tappet or a roller set up?
The other thing to consider is your transmission type and rear gearing.
Everything has to work together or you could end up extremely unhappy with the results.
My other advice is to purchase the heads bare and purchase the springs, rockers, lifters separately.
Again, they all need to work together.
Do you want the engine to make more power in the low to mid rpm range, or do you want it to make more power on the top rpm range?
What are your total end plans for the engine and what are you going to use the car for?
The wrong head and cam choice to save a few bucks could make the engine a real dog and not perform where and how you want it to.
Are you going flat tappet or a roller set up?
The other thing to consider is your transmission type and rear gearing.
Everything has to work together or you could end up extremely unhappy with the results.
My other advice is to purchase the heads bare and purchase the springs, rockers, lifters separately.
Again, they all need to work together.
Thread Starter
Instructor
Joined: Apr 2018
Posts: 165
Likes: 92
From: Buxton ME
Thanks for responses. Looking more for broad torque through 5,000 rpm than a 6,000 rpm screamer. 1977 C3, 4-speed car with 3.36 gears. I've done the basics - headers and 2.1/2" exhaust, Lars' treatment to the Q-jet and Dizzy and an Edelbrock performer. On the chassis dyno, it gained 50 hp. The mods I'm proposing look fairly common and worth another 75 hp or more.
The 703 is a flat tappet, I'm also considering going down one step to the 219/227 cam. I have the 213/219 version in a Pontiac and it makes gobs of torque, but I wish it had a little more after 4,500 rpm.
My only concern about the Summit heads is the 195 cc intake runners versus 175 on the DH175's. Bigger runners is more for high end power?
I see the Skip Whites, wow, less than $900 for the pair! But, they have 200 cc runners, is that detrimental to the low- and mid-range torque?
The 703 is a flat tappet, I'm also considering going down one step to the 219/227 cam. I have the 213/219 version in a Pontiac and it makes gobs of torque, but I wish it had a little more after 4,500 rpm.
My only concern about the Summit heads is the 195 cc intake runners versus 175 on the DH175's. Bigger runners is more for high end power?
I see the Skip Whites, wow, less than $900 for the pair! But, they have 200 cc runners, is that detrimental to the low- and mid-range torque?
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Brett Foote
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2025 C3 of the Year Finalist - Modified
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Cruise-In VIII Veteran
I have a similar car. 4 speed, same diff ratio.
flat top pistons, .015 shim type headgaskets.
64 cc heads, 180 runners. Comp, Xtream Energy 268 Cam on 1.6-1 rockers. Makes great power from 2,000 RPM up.
My suggestion, run the 175 or 180 runners. And a good intake manifold that suits your needs that closely matches your heads.
flat top pistons, .015 shim type headgaskets.
64 cc heads, 180 runners. Comp, Xtream Energy 268 Cam on 1.6-1 rockers. Makes great power from 2,000 RPM up.
My suggestion, run the 175 or 180 runners. And a good intake manifold that suits your needs that closely matches your heads.
Le Mans Master
Joined: May 2007
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From: North tonawanda NY
Le Mans Master
Joined: May 2007
Posts: 5,022
Likes: 1,120
From: North tonawanda NY
Eric Weingartner also did extensive testing on both a set he ported and stock castings and had positive things to say about them. He did a long multi step porting series of videos on you tube about them. I only remember all this because I researched the crap out of budget heads for over a year before making my choice. I bought the 190 size casting though for my 355.
I replaced a set of dart iron eagle 180s with the aluminum chinese 190 castings (im told the same castings are sold as the 195 also so) I had to rejet my carb to fatter jets as the flow increase was noticeable and though my engine rarely sees rpms over even 4000 I did not feel any loss in power at lower rpms whatsoever.
Last edited by augiedoggy; Mar 12, 2024 at 11:40 PM.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
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From: New Braunfels Texas
After using two pairs of TF DH175's......I can recommend them highly.....high quality and work extremely well on 350-383.....my other choice is the 180 Dart Pro 1 Platinum....but they are so high priced now........
The Brodix IK180 is an excellent piece too that needs a little cleanup in the port IMHO....but will work fine out of the box and make good power for a decent price.
I don't use AFR....never heve.....just never had any experience with them as they were too far away and hard to work with........just one of those things.
Jebby
The Brodix IK180 is an excellent piece too that needs a little cleanup in the port IMHO....but will work fine out of the box and make good power for a decent price.
I don't use AFR....never heve.....just never had any experience with them as they were too far away and hard to work with........just one of those things.
Jebby
Thread Starter
Instructor
Joined: Apr 2018
Posts: 165
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From: Buxton ME
I watched Eric's videos in the middle of the night when I couldn't sleep mulling over head options. He's says he's dis-proved the smaller runner theory on torque, but he's testing a 600 HP 408 with a huge cam and testing 195 versus 215 cc heads, both of which might be too small for that motor. Not sure that applies to my 350 that I'm trying to get maybe 350 hp and 400 ft-lbs out of.
I'm going to call Skip White's today, but I'm leaning towards biting the bullet for the DH175's. I like the 175cc runner and the 60 cc chamber for a little extra compression. My second choice is the AFR Enforcers, pretty good at $1,250 / pair. The Brodix are $1,250 each!
Also leaning toward the more moderate 219 / 227 cam. I don't race this car, unless I'm late for happy hour....
For this application, I plan to re-use my rebuilt Q-jet and Performer intake manifold and re-jet the carb as required. Anyone see that as a big mistake?
Thanks for all the responses.
I'm going to call Skip White's today, but I'm leaning towards biting the bullet for the DH175's. I like the 175cc runner and the 60 cc chamber for a little extra compression. My second choice is the AFR Enforcers, pretty good at $1,250 / pair. The Brodix are $1,250 each!
Also leaning toward the more moderate 219 / 227 cam. I don't race this car, unless I'm late for happy hour....
For this application, I plan to re-use my rebuilt Q-jet and Performer intake manifold and re-jet the carb as required. Anyone see that as a big mistake?
Thanks for all the responses.
Old Pro Solo Guy
Joined: Dec 2017
Posts: 8,053
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From: Marlton NJ
<snip>
Would pair with a Lunati Voodoo 703 cam (227/233 @ .050").
The 703 is a flat tappet, I'm also considering going down one step to the 219/227 cam. I have the 213/219 version in a Pontiac and it makes gobs of torque, but I wish it had a little more after 4,500 rpm.
My only concern about the Summit heads is the 195 cc intake runners versus 175 on the DH175's. Bigger runners is more for high end power?
I see the Skip Whites, wow, less than $900 for the pair! But, they have 200 cc runners, is that detrimental to the low- and mid-range torque?
Would pair with a Lunati Voodoo 703 cam (227/233 @ .050").
The 703 is a flat tappet, I'm also considering going down one step to the 219/227 cam. I have the 213/219 version in a Pontiac and it makes gobs of torque, but I wish it had a little more after 4,500 rpm.
My only concern about the Summit heads is the 195 cc intake runners versus 175 on the DH175's. Bigger runners is more for high end power?
I see the Skip Whites, wow, less than $900 for the pair! But, they have 200 cc runners, is that detrimental to the low- and mid-range torque?
Here are the HP & TQ figures for the 4 stock 327s in the c2s.
250hp @ 4400, 350 ft-lbs @ 2800
300hp @ 5000, 360 ft-lbs @ 3200
350hp @ 5800, 360 ft-lbs @ 3600
365hp @ 6200, 350 ft-lbs @ 4000
The first two basically have your L48 cam with 195* duration. The differences are in heads, valves, exhaust specs, CR, etc.
The third one (L79) basically has a similar to 703 cam with 224* duration.
Those do start to lose some bottom end TQ but do rev well to 6300+.
That may or may not be what you want.
The fourth one (L76) is the solid lifter cam'd "screamer" with even more duration, around 239* if you want to compare it to a H cam. They rev to like 6800.
If I were you, I would pick the in between cam, the 217* dur one. It is still 20* bigger than your L48 cam and should run terrific, without losing any lower end TQ. And it will pull well from 1000rpm, unlike the 227* cam, which will have a surge at 1500 and then pull well.
It will pair very nicely with 175 or 180cc heads, and make peak HP at 5000, and rev well to 5500.
I would not go with the 227* cam, unless you want to use the higher rpms. But you will lose some low end. But some of us like 6500rpm! LOL.
In your case you will probably gain 40HP from the head change, and 30HP from the cam change. There is probably only 10-15HP difference in the two cams you mentioned. Have fun.
Last edited by leigh1322; Mar 13, 2024 at 06:34 PM.
Thread Starter
Instructor
Joined: Apr 2018
Posts: 165
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From: Buxton ME
Thanks, Leigh, good summary and I agree on the 217 cam. The 213 in my Pontaci pulls hard off-idle thru 4,500 rpm, which is enough on a long-stroke street engine.
Will keep you all posted on progress....
Will keep you all posted on progress....
Safety Car
Joined: Nov 2001
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From: northern CA
Concerned more about low to mid range torque I decided on the TF 175 heads for my C2 327 (.040). The 60cc chambers, flat top pistons, and .015 steel shim head gaskets upped the compression ratio to 10.0 ..
Intake manifold is an Edelbrock 2703 EPS with a drop base air filter assembly and 2 inch tall air filter for stock hood clearance. The 2 inch filter and drop base did appear to choke off some air flow going into the carb air horn. The filter top lid was modified to add more air filter media to enhance air flow.
The cam is the factory LT-1 solid lifter with about 25K miles on it now. The previous diff ratio was a 4:11 .. As the car is pretty much a cruiser now a 3:08 diff replaced the 4:11’s.
Performance wise I’m ok with the slower climbing rev capability running 3:08’s. Occasional max revs see something on the order of 4500-5000.
John
Intake manifold is an Edelbrock 2703 EPS with a drop base air filter assembly and 2 inch tall air filter for stock hood clearance. The 2 inch filter and drop base did appear to choke off some air flow going into the carb air horn. The filter top lid was modified to add more air filter media to enhance air flow.
The cam is the factory LT-1 solid lifter with about 25K miles on it now. The previous diff ratio was a 4:11 .. As the car is pretty much a cruiser now a 3:08 diff replaced the 4:11’s.
Performance wise I’m ok with the slower climbing rev capability running 3:08’s. Occasional max revs see something on the order of 4500-5000.
John
Last edited by mrg; Mar 14, 2024 at 06:06 PM.
Racer
Joined: May 2020
Posts: 498
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I have a 383 9.6cr w/200cc heads and a 225/232 cam on 114 LSA w/ dual plane intake and 750 carb.
This engine is extremely responsive and has very strong torque.
Getting ready to pull the trigger on Edelbrock’s dual quad set up for possibly better top end horse power.
This engine is extremely responsive and has very strong torque.
Getting ready to pull the trigger on Edelbrock’s dual quad set up for possibly better top end horse power.
Le Mans Master
Joined: May 2007
Posts: 5,022
Likes: 1,120
From: North tonawanda NY
As far as budget heads nothing ive seen any data on can touch the performance at the same costpoint of the chinese casting sold under different names like the enforcers,skip white and blueprint heads.
Last edited by augiedoggy; Mar 14, 2024 at 11:12 PM.
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Bottom line, ANY aftermarket aluminium head is going to be better than a smog era stock head.
And I agree, build what you can afford, it'll be heaps better than stock! And maybe won't be the very best.
But if you get caught up in that game, the spending never stops! There will always be a guy with a faster car! Always! No matter how much you spend!
And I agree, build what you can afford, it'll be heaps better than stock! And maybe won't be the very best.
But if you get caught up in that game, the spending never stops! There will always be a guy with a faster car! Always! No matter how much you spend!
