Best head for bottom end

[7upstang]

Hello,

My current mods are as follows:
Cobra Intake, 3:55 gears, 65MM Throttle body, Pro- M 77MM Mass Air, BBK 1-5/8 Long tubes, Subframes Etc,

The car is Strictly street. No aspirations of drag racing and no street racing. I've done the earlier mods just because it makes the car alot more fun to drive. To that end, one of the things I love about driving the car is torque and low end acceleration. With the 3:55s it pulls great. I'm finally ready to do heads and I want to get some more power without losing all my torque.

I really think the Thumper heads look to be my best bet, but I can get a killer deal on some new Performer 5.0s and I am wondering just how much bottom end I will lose by going to them.

I know the TFS and AFR 165s are a better head, but like I said, The Eddys are about half the price.

I was also thinking of keeping the stock cam because once again, torque is everything.

The car is a convertible BTW.

Any help would be greatly appreciated.

PS. anybody seen or heard from Mike/AKA thumper lately?

Sorry about the long post.

 

[fidstang]

Hello,

My current mods are as follows:
Cobra Intake, 3:55 gears, 65MM Throttle body, Pro- M 77MM Mass Air, BBK 1-5/8 Long tubes, Subframes Etc,

The car is Strictly street. No aspirations of drag racing and no street racing. I've done the earlier mods just because it makes the car alot more fun to drive. To that end, one of the things I love about driving the car is torque and low end acceleration. With the 3:55s it pulls great. I'm finally ready to do heads and I want to get some more power without losing all my torque.

I really think the Thumper heads look to be my best bet, but I can get a killer deal on some new Performer 5.0s and I am wondering just how much bottom end I will lose by going to them.

I know the TFS and AFR 165s are a better head, but like I said, The Eddys are about half the price.

I was also thinking of keeping the stock cam because once again, torque is everything.

The car is a convertible BTW.

Any help would be greatly appreciated.

Sorry about the long post.

You wont loose enough to really care about with the 3.55's. Sure, you'll notice it but, you wont care because of all power you will gain from 3400rpms on up. You would probably be better off with some GT40 irons lightly ported and the all important performance valve job. That would be my suggestion for a street car with little to no racing.

 

[low5.0]

Just go with the performers. You will be kicking yourself later down the road when you want more power if you get the thumpers. Im running trick flows and love them.

 

[mattmcdan]

I just picked these GT40X's up. I think they are offered at a very fair price, and we all know they are high quality coming from FMS.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&ih=013&item=230011063794

 

[7upstang]

Just go with the performers. You will be kicking yourself later down the road when you want more power if you get the thumpers. Im running trick flows and love them.

What gears are you running? what block?302 or Stoker? Any nitrous- S/C?
The reason I ask is, most of the guys that I know that are running AFRs or Trick flows, are running 3:73s or 4:10 gears to make up for the lack of bottom end.

 

[ls1beater4eva]

well just my o2, i would go with a set of afr 185 cause there not much more then the 165s and prob the best choice and power gain for your buck.

 

[fidstang]

I think he stated that he wanted a street car that doesn't even get street raced. So what good do heads with 2.02 valves do for him. Now if he plans on staying in the 3500rpm and up range then yeah, go all out spend a lot on some heads. But, honestly, he'll spend most his time in the 1500 to 4500rpm range where the ported stock irons will produce a better power curve. I got 300 whp from GT40 irons from a 93 cobra that were lightly ported and had a valve job. I could beat most of the trickflow, afr and canfield guys to about the 2000ft mark in the 1320. Most would only beat me by .2-.4 seconds. They all had 20-30 more rwhp then me.
I still say for what he stated that he wanted. GT40 irons are his best bet.

 

[7upstang]

I think he stated that he wanted a street car that doesn't even get street raced. So what good do heads with 2.02 valves do for him. Now if he plans on staying in the 3500rpm and up range then yeah, go all out spend a lot on some heads. But, honestly, he'll spend most his time in the 1500 to 4500rpm range where the ported stock irons will produce a better power curve. I got 300 whp from GT40 irons from a 93 cobra that were lightly ported and had a valve job. I could beat most of the trickflow, afr and canfield guys to about the 2000ft mark in the 1320. Most would only beat me by .2-.4 seconds. They all had 20-30 more rwhp then me.
I still say for what he stated that he wanted. GT40 irons are his best bet.

I agree, and your right, most of my driving will be in the 1500-5000 RPM range. The thing is, IF I get the Edelbrocks, do you think the power band will be that much higher than Ported GT40s or Thumpers. I know the port velocity will be great with the GT 40s, but if I can get a great deal on these Edelbrocks, (600 Canadian- Friend bought them-wrecked his car before he could put them on) I think it will be worth it, but ONLY if it doesn't leave me with a car that has no fun factor from 2-3500 RPM.

There is also the instant gratification of buying the heads NOW, instead of waiting for Thumper or a porting shop.

If you really think I'll enjoy the GT 40s more though, I'll tell him to sell the Edelbrocks on Ebay and find some Thumpers or GT40S. It does sound like you understand what I want from the car.

Thanks for the input.

 

[fidstang]

I agree, and your right, most of my driving will be in the 1500-5000 RPM range. The thing is, IF I get the Edelbrocks, do you think the power band will be that much higher than Ported GT40s or Thumpers. I know the port velocity will be great with the GT 40s, but if I can get a great deal on these Edelbrocks, (600 Canadian- Friend bought them-wrecked his car before he could put them on) I think it will be worth it, but ONLY if it doesn't leave me with a car that has no fun factor from 2-3500 RPM.

There is also the instant gratification of buying the heads NOW, instead of waiting for Thumper or a porting shop.

If you really think I'll enjoy the GT 40s more though, I'll tell him to sell the Edelbrocks on Ebay and find some Thumpers or GT40S. It does sound like you understand what I want from the car.

Thanks for the input.

Take the Edelbrocks if you are getting that good of a deal. You will notice a difference in the 1500 to 3400 rpm but it wont be the big of a deal. Just make sure when you but them you have everything needed for them. Like, if there stud mounts, check the condition of the guide plates. Check the spring seats for wear and don't forget new pushrods, must be hardened ones. You'll be happy with them.

 

[7upstang]

They're pedestal mount, Do I still need hardened push rods? They're still new and not out of the Box so I'm not worried about the condition. (I wouldn't be getting as good of a deal if i hadn't done some free recording for him)

 

[Kerpal]

I've been wondering the exact same thing... I'm looking at the Performers as well and with my daily driver Stang I'm much more concerned with the 1500-4500 RPM powerband than higher-RPM potential...

anyone have solid numbers on how the Performers' low-end power compares to that of ported E7's and GT40's?

 

[5spd GT]

185 will require flycutting to the stock bottomend. I would go with 165's.

 

[fidstang]

They're pedestal mount, Do I still need hardened push rods? They're still new and not out of the Box so I'm not worried about the condition. (I wouldn't be getting as good of a deal if i hadn't done some free recording for him)

New pushrods should always be on the list when doing a swap. Not, saying that the stock ones wont hold up, you just never know when a weak one is going to bend. You can't tell if it's weakend by just looking at it. Also, check your lifters while your in there, pull them out keeping them in order and inspect the roller tip to see if there is any problems with the cam bearings or cam itself.
If your getting the heads for about 560 us dollars I'd say that's a good deal and out of the box they will perform almost as well as good ported GT40 irons.

 

[QDRHRSE]

If you wish to retain bottom end the best thing that you can do is go with a head that has a smaller valve. The TFS and AFR's are absolutely out of the question. You can pick up a set of aluminum GT40y's very cheap. They are a direct bolt on- you don't need to change anything. The GT40p's are good too but need a custom header....by the time you're done the GT40y's are cheaper.

For bottom end you need a lot of port velocity. The bigger the intake runner- the worse the port velocity gets. People often make the mistake of going with overly large valves and exhaust too. Big mistake. All you get is a car with a peaky powerband.

The Edelbrocks are a good solid head. I think that the Twisted wedge is the best head there is but not for your configuration. The AFR 165's are really good but overkill and expensive as well.

 

[5spd GT]

QDRHorse - The AFR 165's and TW's are very very similar in power output. Saying they are overkill shows they you are not familiar with the power numbers between the two. 165's have a slight advantage over the entire power range over the TW's. You get what you pay for. Want quality aluminum pieces get the AFR's or TW's.

 

[7upstang]

If you wish to retain bottom end the best thing that you can do is go with a head that has a smaller valve. The TFS and AFR's are absolutely out of the question. You can pick up a set of aluminum GT40y's very cheap. They are a direct bolt on- you don't need to change anything. The GT40p's are good too but need a custom header....by the time you're done the GT40y's are cheaper.

For bottom end you need a lot of port velocity. The bigger the intake runner- the worse the port velocity gets. People often make the mistake of going with overly large valves and exhaust too. Big mistake. All you get is a car with a peaky powerband.

The Edelbrocks are a good solid head. I think that the Twisted wedge is the best head there is but not for your configuration. The AFR 165's are really good but overkill and expensive as well.

I thought the GT40Y heads had bigger valves than the Eddy performer 5.0
(194 intake 160 exhaust versus 190 intakes 160 exhaust for the edelbrock)

That is why I am a little worried about going to any of the aftermarket aluminum heads, the loss of port velocity.

The deal I'm getting on the Edelbrocks is amazing, so I'm willing to make a bit of a trade off, versus GT40 iron, as long as it doesn't remove every last bit of torque from the bottom end.
What do you think?

 

[Grn92LX]

Stick with the edelbrocks since you said you can get them cheap.

 

[Tonys96Cobra]

Yes get the Edelbrocks. I will buy you a set of P heads and trade them for your Eddys. Thats what you need to do. Now. ASAP.

 

[QDRHRSE]

The TW's have a slightly larger port and a bigger intake valve. Raw power is not what we are looking for in this situation. The AFR would make more lowend tq with a stock cam. The design of the TW's chamber is a lot more effient and from experience I have found the TW's to work a lot better....just not in this case. I would gladly trade my AFR 185's for an equally prepped set of TW's. I would say that I know quite a bit about the differences in the heads as I have tried most of them. Going back to the original point of the thread- the TW is a bit much and the AFR is borderline but probably not worth it for his application imo. I am not only familiar with the power numbers on paper but I am familiar with the output based on ET's and real life experience. Get off your couch and drop the magazines and get some real experience and #'s. Call Rick Anderson @ Anderson Ford and tell them how much better the AFR heads are and you will likely get the 20 minute lecture that I got. Also, how can you compare the quality of a TFS or AFR head to an Edelbrock or Ford cylinder head? That's crazy talk. Come on man. You're better than that.

 

[QDRHRSE]

I thought the GT40Y heads had bigger valves than the Eddy performer 5.0
(194 intake 160 exhaust versus 190 intakes 160 exhaust for the edelbrock)

That is why I am a little worried about going to any of the aftermarket aluminum heads, the loss of port velocity.

The deal I'm getting on the Edelbrocks is amazing, so I'm willing to make a bit of a trade off, versus GT40 iron, as long as it doesn't remove every last bit of torque from the bottom end.
What do you think?

I'm not sure of the valve size but the ports are dinky. They make a ton of bottom end. If the deal you're getting on the edelbrocks is that good, what are you waiting for? There is nothing wrong with those. For a nearly stock set up I would stick with a nearly stock head. I have never tried the Performer head, only the Performer RPM. They were ok. From a cost/performance perspective the Y heads are the most bang for your buck as it seemed like a slight concern for you. I think that you can find them for under $700. If you can get something comprable for less- you should.