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DRR Trophy
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Sorry for the late response guy and think you for all the input.

I’d love to just change the cam but my valves/springs will only handle .600 lift. By my estimate I’d be spending $600 to upgrade this on a set of heads that are truly just street heads. The engine was originally built for my streetcar. When I built this s10 for my daughter when we got her drivers license I didn’t expect her to need to go very fast so I didn’t change much on it. The truck ran 11.0s with the 355ci. We spoon a rod at the end of last season so I stroked it and put the domes and good bottom end. I knew the heads/cam where still street stuff but it worked good at the time. Now that the tracks are closed and we have some down time I want to go ahead and step up the top end. I didn’t see the point in changing the cam until I got a head to handle it. Her brothers(15)car runs 9.80 and we slow it down with a restrictor plate to keep it in the 10s. She makes comments from time to time about her truck being slow so I’m just trying to get hers to run about what his runs.

The truck traps in the 1/4 at about6900. If we increase power to run a low 10 that will increase to about 7200 which is way I built the bottom to hold 7500. Most races here are going to 1/8 so rpm limit shouldn’t be a problem.

Comp cam suggested a custom cam 276/.284 duration @ .050" and .672/.672 lift with a LS of 108

Giving piston to valve clearance. What do y’all think? Seams big to me. Also what are suggestions for heads? I contacted Chad but he said his heads would be overkill
 
Posts: 32 | Location: Zachary | Registered: November 09, 2018Reply With QuoteReport This Post
DRR Pro
Picture of Alaskaracer
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You've got some good advice from some very knowledgeable people here...I'd take it to heart and decide from there....


Mark Goulette
Owner/Driver of the Livin' The Dream Racing dragster
www.livinthedreamracing.com
"Speed kills but it's better than going slow!"
Authorized Amsoil Retailer
 
Posts: 1465 | Location: Back home in Alaska! | Registered: February 13, 2011Reply With QuoteReport This Post
DRR S/Pro
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quote:
Originally posted by Fatboy81:
Sorry for the late response guy and think you for all the input.

I’d love to just change the cam but my valves/springs will only handle .600 lift. By my estimate I’d be spending $600 to upgrade this on a set of heads that are truly just street heads. The engine was originally built for my streetcar. When I built this s10 for my daughter when we got her drivers license I didn’t expect her to need to go very fast so I didn’t change much on it. The truck ran 11.0s with the 355ci. We spoon a rod at the end of last season so I stroked it and put the domes and good bottom end. I knew the heads/cam where still street stuff but it worked good at the time. Now that the tracks are closed and we have some down time I want to go ahead and step up the top end. I didn’t see the point in changing the cam until I got a head to handle it. Her brothers(15)car runs 9.80 and we slow it down with a restrictor plate to keep it in the 10s. She makes comments from time to time about her truck being slow so I’m just trying to get hers to run about what his runs.

The truck traps in the 1/4 at about6900. If we increase power to run a low 10 that will increase to about 7200 which is way I built the bottom to hold 7500. Most races here are going to 1/8 so rpm limit shouldn’t be a problem.

Comp cam suggested a custom cam 276/.284 duration @ .050" and .672/.672 lift with a LS of 108

Giving piston to valve clearance. What do y’all think? Seams big to me. Also what are suggestions for heads? I contacted Chad but he said his heads would be overkill


If low 10's is the goal, change the cam to the right solid lifter or roller cam for your deal. As Ed stated, Comp's is OTL! You likely talked to someone who knows little other than to read from a catalog. Ballpark, take 10 to 15 degrees off the duration and close the lobe separation 2 to 4 degrees. To fine tune the cam you need to know the real compression ratio, not the text book listing for that piston and how much lift those heads with the valves in them can take, ie max installed height. As far as piston to head goes, you need to check it no matter what you change which includes new heads also.

Low 10's with your heads is achievable! Good luck.
 
Posts: 2149 | Location: Tewksbury, MA,USA | Registered: November 03, 2000Reply With QuoteReport This Post
DRR Top Comp
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Ah ha ha ha ha ha! The cam is gonna improve the efficiency of the converter, at lower rpm at the stripe

oh my gawd what a cluster F! Laughing Hard
 
Posts: 9398 | Location: Madeira Beach Fl. | Registered: June 12, 2018Reply With QuoteReport This Post
DRR Elite
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your way out of your league, step aside.
 
Posts: 13522 | Location: NJ | Registered: August 20, 2000Reply With QuoteReport This Post
DRR Top Comp
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Proceed, ya'll are some entertaining mofo's no doubt!

 
Posts: 9398 | Location: Madeira Beach Fl. | Registered: June 12, 2018Reply With QuoteReport This Post
DRR Trophy
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Yes that cam seamed a bit much. I’m going to get with my local engine builder and see what he would spec out for the cam
 
Posts: 32 | Location: Zachary | Registered: November 09, 2018Reply With QuoteReport This Post



DRR Pro
Picture of SpeierRacingHeads
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I built myself a 3.48 stroke, 379 with a set of my 205cc CNC heads. 10-1, 750 carb, true 91 octane, 231/235 cam, .550 lift, for my street car. It made 510tq@4000 and 548@6300..

We didn't find every ounce of power because it got a elbow/EFI/throttle body in the car.

You can easily make the same power with an as-cast head and a much smaller cam than you were told.
 
Posts: 1405 | Location: Hays Kansas | Registered: January 23, 2006Reply With QuoteReport This Post
DRR S/Pro
Picture of "The Bender"
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quote:
Originally posted by 1320racer:
Very achievable with just a cam change but depending on what the converter flashes to and drops to after the shift now, it may need a tweek. I'm guessing the converter is loose now so the right cam would only improve it's efficiency.


I'm with Ed on this one....


272" Spitzer
540 Chevy
The Blower Shop XR1
FTI XPM Series Converter
FTI Level 6 Powerglide
3.69@199
.916 60'

2017 Bradenton Heads Up Madness
Open Outlaw Champ

2018 PDRA T/D #5
2019 PDRA T/D #2

2020 Retired From T/D Competition....

2020 Bradenton NMCA Hemi Shootout Winner

2021 getting back into bracket racing with a Gen3 Hemi powered 87 Cutlass.
 
Posts: 3096 | Location: Yes | Registered: July 08, 2009Reply With QuoteReport This Post
DRR S/Pro
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quote:
Originally posted by Mike Rietow:
quote:
Originally posted by "The Bender":
quote:
Originally posted by 1320racer:
Very achievable with just a cam change but depending on what the converter flashes to and drops to after the shift now, it may need a tweek. I'm guessing the converter is loose now so the right cam would only improve it's efficiency.


I'm with Ed on this one....


2, 10 or 200 greenhorns in here who don't know what they're talking about agreeing with Ed, won't change performance fundamentals.

The only way the converter gets more efficient with a cam change, is if the engine makes more power, goes faster and cross's at higher RPM - MPH.

That's a fact, not an opinion.


Here's another fact for Mr Absolute! It would if it were modified to better fit the new cam or whatever, so that's a second way to your ONLY WAY!

Just saying!

BTW, I replied to you on this so not to leave you out and feeling lonely regarding this tread. Laughing very hard

Got a question for you, since you are so smart, cuz you say u r, why are you wasting your time here, shouldn't you be working on a cure for the Covid -19????

This message has been edited. Last edited by: TOP38,
 
Posts: 2149 | Location: Tewksbury, MA,USA | Registered: November 03, 2000Reply With QuoteReport This Post
DRR Elite
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Mike, I'm going to post over at YB, thanking them for chasing you and all your aliases out of there and with nowhere to go, landing here. Because of you, Top38, Bender and I now agree on performance advice and I suspect as long as you are around we will in many more threads. Big Grin
 
Posts: 13522 | Location: NJ | Registered: August 20, 2000Reply With QuoteReport This Post
DRR Top Comp
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Here's where we are greenhorns. Not opinion but fact.

Anyone else?

2, 10 or 200 greenhorns in here who don't know what they're talking about agreeing with Ed, won't change performance fundamentals.

The only way the converter gets more efficient with a cam change, is if the engine makes more power, goes faster and cross's at higher RPM - MPH.

That's a fact, not an opinion. This is not a subjective matter or I wouldn't be here.
 
Posts: 9398 | Location: Madeira Beach Fl. | Registered: June 12, 2018Reply With QuoteReport This Post
DRR S/Pro
Picture of "The Bender"
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Does this mean that Mike has "out-Ed'ed" even Ed?

Falling of chair laughing


272" Spitzer
540 Chevy
The Blower Shop XR1
FTI XPM Series Converter
FTI Level 6 Powerglide
3.69@199
.916 60'

2017 Bradenton Heads Up Madness
Open Outlaw Champ

2018 PDRA T/D #5
2019 PDRA T/D #2

2020 Retired From T/D Competition....

2020 Bradenton NMCA Hemi Shootout Winner

2021 getting back into bracket racing with a Gen3 Hemi powered 87 Cutlass.
 
Posts: 3096 | Location: Yes | Registered: July 08, 2009Reply With QuoteReport This Post
DRR Top Comp
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Generally speaking, people can't handle the Truth. That's where I come in. Smile Laughing Hard

 
Posts: 9398 | Location: Madeira Beach Fl. | Registered: June 12, 2018Reply With QuoteReport This Post



DRR Top Comp
Picture of Curly1
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For Cam recommendation I would call all of the major manufacturers and get their opinions. You will quickly see a few are way out of line with others. Disregard them.

I called one big cam company one time for a recommendation. They asked me "Big Block or small Block Drag or Dirt track? Here is cam you need" Obviously I did not buy from them. They have went from a good cam company to sales team.

My last few cams have been from Bullet and they have been great. When you call them they will ask you a bunch of questions about what you have, what you want to achieve and will give you a good recommendation and how it will help you.

There are some who think they know more about cams than the people who do it for a living.


https://postimg.cc/gallery/np3zpruo/
"Dunning-Kruger Effect"
-a type of Cognitive bias where people with little expertise or ability assume they have superior expertise or ability. This overestimation occurs as a result of the fact that they do not have enough knowledge to know they don't have enough knowledge.

Before you argue with someone ask yourself, "Is this person mentally mature enough to grasp the concept of a different perspective?" If not there is no point to argue.

4X NE2 CHAMPION. 2020 TDRA NE2 Champion
 
Posts: 4001 | Location: United States of Texas | Registered: April 02, 2011Reply With QuoteReport This Post
DRR Pro
Picture of SpeierRacingHeads
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I have and use, with great success, a copy of controlled induction. I'd be happy to run the cam so we can see how wrong it is!
 
Posts: 1405 | Location: Hays Kansas | Registered: January 23, 2006Reply With QuoteReport This Post
DRR Elite
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There are a few here that definitely know more about cams then the minimum wage "tech" guy on the other end of the phone line.
 
Posts: 13522 | Location: NJ | Registered: August 20, 2000Reply With QuoteReport This Post
DRR Pro
Picture of SpeierRacingHeads
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I did it for a goof. Modeled it off a AFR 210 head, and 6800 peak rpm. 13-1, 383

 
Posts: 1405 | Location: Hays Kansas | Registered: January 23, 2006Reply With QuoteReport This Post
DRR Pro
Picture of SpeierRacingHeads
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It wants more because the head doesn't flow as well.

 
Posts: 1405 | Location: Hays Kansas | Registered: January 23, 2006Reply With QuoteReport This Post
DRR Pro
Picture of SpeierRacingHeads
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Here is the full sheet. The head flowed way more than I thought. But this is CI.

 
Posts: 1405 | Location: Hays Kansas | Registered: January 23, 2006Reply With QuoteReport This Post
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