Intake question for the engine guru's.... - The 1947 - Present Chevrolet & GMC Truck Message Board Network

tx69gmc · 05-30-2006, 10:14 PM

Hey all-

I am in the process of upgrading the top end of my crate 350. Here is what I am going to use. GM Vortec heads, Comp Cams XE268H, Edelbrock 750, 1.6 Roller Rockers. My question is on the intake. Currently, I have stock heads and cam with Performer RPM and Edelbrock 650. Truck seems to be sluggish off of idle. Would this be due to the RPM intake? Am I robbing low end torque by using the Performer RPMintake. I was planning on using a Performer RPM on the new build but was wondering if the standard Performer might be a better torque choice. Thoughts???

**clay68c10** · 05-30-2006, 10:17 PM

The regular Performer will probably match the rpm range of the cam better. I had a 268 comp in a 350 way back and it ran pretty strong. I was running a Weiand stealth intake.

Gray Ghost · 05-30-2006, 10:18 PM

The RPM kicks in about 2500 rpm iirc....the performer starts at 1500 and will give you more low end torque. I had Vortec heads on mine and wasn't that impressed, there's better heads out there for sure.

The 268 cam will help a bunch.

**Daubs** · 05-30-2006, 10:31 PM

I'm just a slight motor head, but checking the edelbrock web site shows the following:

PERFORMER (idle-5500 rpm)
PERFORMER RPM (1500-6500 rpm)

If you switch to Vortec heads you are going to have to get new intake to match. I'd stick with the standard Performer if you want more low end.

The 268H lists as "Good street performance with stock converter, choppy idle." That cam is going to have Duration @0.05 of 218 & 218. That is going to push your power sweet spot higher in RPM range (less low end grunt).

For more low end grunt you might look at following cams:

Dual Energy 255DEH Cam: "Good torque, good mileage. Good RV & towing cam. Smooth idle"
High Energy/Marine 260H Cam: "Vans, pickups, 4WD & towing, in 350 c.i., good idle, strong mid range torque"
High Energy 252H Cam: "Strong torque, excellent mileage for 327-400 c.i., has smooth idle, likes high axle ratios"

I made mistake of getting a cam that was too "big" for my 82 4x4 manual tranny truck with 3.08 rear end. No low end grunt. Ended up pulling that cam and putting something close to 252 grind in. Much better.

What tranny and rear end are you planning to run? Is this 2 wheel or 4 wheel drive? What do you want to do with truck?

tx69gmc · 05-30-2006, 10:35 PM

Thanks for the info. I have the TH350 with 3.73's in the rear. Because of the tranny and gears, I am looking to get the most low end as that is most likely where most of my time will be spent. This is not a daily driver and I am looking for a seat of the pants weekend cruiser.

**Daubs** · 05-30-2006, 10:44 PM

You might think about swapping out the RPM for a standard Performer and keep the Edelbrock 650 carb and stock heads / cam.

I'm assuming you got the base level crate motor, the 260 HP version (part number 10067353 -- not the 290 HP version)

What size tires are you running? Two or four wheel drive?

tx69gmc · 05-30-2006, 10:55 PM

Yep. Base level crate 350. 2WD with 17's. I have most of the parts already but might need to swap out intake and cam. I also currently have long tube headers which are hanging too low with my front end being dropped. I have heard a lot about the Ram Horn Manifolds. What do you guys think?

boot85 · 05-30-2006, 10:55 PM

I agree with Daubs,
if you are after a low end torque motor you have to forget about the fab of the high lift cams and big valve heads. The truth of the matter is that for low end torque you want a low duration cam and small valves. The heads do not have to be top of the line either, the stock heads would be just fine with some new valve seats and new guides. As for the intake any of the Edlebrock Proformer Series would work just fine. Since they are a dual plane intake and that design is for idle up to about 5500 RPM.

Hope this helps

boot85 · 05-30-2006, 11:04 PM

After seeing your last post, another thing to think about if you really are after a low end toque engine is the exhuast. The larger exhuast you have the more you are taking away from the low end torque. For example if you have 1 3/4' exhuast you are going to be robbing your low end torque. You would be better suited to go with a smaller primary rather than a larger one. If I were you I would go with the tried and true chevy Ram Horns, you will surely get the best bang for your buck. Even though they look as pretty as a header they are way more functional for your application.

**Daubs** · 05-30-2006, 11:08 PM

Base level 350 is the 260HP version, same engine as mine (it's on engine stand now...waiting on a few parts before install). You might be able to get away with bigger cam because of your auto tranny. But be careful. Boot85 is right, smaller valves and lower duration cam, smaller tube headers (and smaller 4 barrel carb) give you better low end grunt.

I would seriously consider starting with Performer intake and keeping everything else as you have it (stock heads, cam, Edelbrock 650 carb). You would really hate yourself if you spent all that $$ on heads, cam, etc., and didn't have the low end you want.

Gray Ghost · 05-30-2006, 11:11 PM

Thanks for the correction on the RPMs...should looked it up, too tired to be doing this from memory.

NewKid · 05-31-2006, 10:54 AM

There is an article at this site that shows a vortec cast iron head that is 23 degree fastburn vortec cast iron that will use 4 and 6 bolt intake manifolds. http://popularhotrodding.com/enginem...0511em_vortec/

djracer · 05-31-2006, 12:15 PM

Quote:

Originally Posted by NewKid

There is an article at this site that shows a vortec cast iron head that is 23 degree fastburn vortec cast iron that will use 4 and 6 bolt intake manifolds. http://popularhotrodding.com/enginem...0511em_vortec/

very good reading in this article! I am a serious vortec fan! I'll post a link to my old street truck on dragtruck.com so you can check it out My old 89 truck is truck of the day today! I ran vortecs on both of these trucks!
http://www.dragtruk.com/ENTRIES/U1G6UF5XJGYS.html I would reccomend either pinning the rocker studs or replacing them with screw in studs! Also you need to clearance the push rod slot to run the 1.6 ratio rockers. If your block is set up for a stock roller cam I would run the zz4 cam (you can buy these cheap as take outs sometimes) or the zz4 hot cam kit with new springs.

Feel free to Pm me If I can help!

72MARIO · 05-31-2006, 09:05 PM

I have the performer RPM on my 67 an would really like to swap out to a perfromer just to see the diffirence. I would like more bottom end power because all the driving I do needs the get go. I also am not very happy with the millage I am getting (12 MPG with a 700R). It's a basic 355 using the 327/350HP cam I thinkit's a 447/447 lift. Thinking it's time to try the swap.

**Daubs** · 06-01-2006, 12:29 AM

Quote:

Originally Posted by 72MARIO

I have the performer RPM on my 67 an would really like to swap out to a perfromer just to see the diffirence. I would like more bottom end power because all the driving I do needs the get go. I also am not very happy with the millage I am getting (12 MPG with a 700R). It's a basic 355 using the 327/350HP cam I thinkit's a 447/447 lift. Thinking it's time to try the swap.

I think that is the Chevy "151" grind cam (327 / 350 HP). Not great cam in a truck, especially a 4x4. Once I got her up to around 2,200 RPM's it screamed! But with 3.08 gears that didn't happen often. Mileage sucked also.

I'd swap her out if I were you.

glock35ipsc · 05-31-2006, 09:23 PM

I have the 260hp crate motor in the 68 too. I run a standard Performer, 650 Edelbrock, and a Comp 268H. At that time, I had the manual 3-speed with 3.73's. Ran great and had awesome low end. When the 68 goes back together, it will have the same set-up, but with a TH350 and about a 2200-2400 rpm converter.

Chevrolet4x4s · 05-31-2006, 10:07 PM

Performer EPS is optimised to Performer series carbs and showed according to Edelbrock about 7hp and 9 ftlbs over the standard Performer intake.A Performer EPS will really wake up a sbc vs the stock intake.
Shane

71chevytruckguy · 05-31-2006, 10:57 PM

i've got a 305 in my '69 with a comp 268h cam with a vintage offenhauser daul port intake intake, carb adapter, a rebuilt q-jet, flat tops pistons, and headers. i've a 4 spd saginaw trans with 3.73 gears out back. it really doesn't start to pull untill u get the engine up to 2000rpm then it really comes to life. i like it and if work fine for me. gets 11 mpg on 93 octane. chris.

Chevrolet4x4s · 06-01-2006, 08:10 AM

RV cams are good for trucks

AKChevyman · 06-01-2006, 08:43 AM

Just to throw another idea out there what about and airgap intake that may help with the low end torque. Just a suggestion.

**Daubs** · 06-01-2006, 09:42 AM

Air gaps are pretty darn cool. But I've heard they don't work good in cooler / cold weather environments. Tough time warming up the engine and carb with the air gap. In a daily driver I'd still stick with the Performer (std)

70c10 · 06-01-2006, 09:57 AM

I don't see anything wrong with the RPM intake with that cam. I would use about a 2500 stall converter. Those heads are good to about .470 lift and the 268 has more than that plus you are adding 1.6 rockers will push it higher so you will need to get the heads setup for that extra lift. Another thing you could do is change your gear ratio since you are running such a tall tire.

glock35ipsc · 06-01-2006, 12:00 PM

Quote:

Originally Posted by 70c10

I don't see anything wrong with the RPM intake with that cam. I would use about a 2500 stall converter. Those heads are good to about .470 lift and the 268 has more than that plus you are adding 1.6 rockers will push it higher so you will need to get the heads setup for that extra lift. Another thing you could do is change your gear ratio since you are running such a tall tire.

Just for everyones info:

The XE268H -

lift @ cam lobe = .318" I/.320" E
lift @ valve w/1.5 rockers = .477" I/.480" E (as advertised by Comp Cams)
lift @ valve w/1.6 rockers = .509" I/.512" E

Jason915 · 06-01-2006, 12:02 PM

I went from a L82 cam and a RPM intake to an EPS and Comp 4x4 cam because the truck would't tow very good at all it had great power after 2500 RPM but didn't have good "truck" low end. Now with the EPS and 4x4 cam it has a tremendious amount of low end power I would have never thought that a 355 with 2.02 X1.60 valves would have this much low end power as this motor has now. The RPM intakes are not for trucks trucks they are designed for cars that are 3600# or lighter.

c10crazy · 06-01-2006, 12:45 PM

jason915, I bet your new power came from the cam mostly!. The 4x4 cam is way better technology. I have never heard RPM intakes are designed for the "specific weight" of a vehicle. They are designed for the RPM usage.

05-30-2006, 10:14 PM	#1
tx69gmc Registered User Join Date: Nov 2005 Location: Denton,TX Posts: 61	Intake question for the engine guru's.... Hey all- I am in the process of upgrading the top end of my crate 350. Here is what I am going to use. GM Vortec heads, Comp Cams XE268H, Edelbrock 750, 1.6 Roller Rockers. My question is on the intake. Currently, I have stock heads and cam with Performer RPM and Edelbrock 650. Truck seems to be sluggish off of idle. Would this be due to the RPM intake? Am I robbing low end torque by using the Performer RPMintake. I was planning on using a Performer RPM on the new build but was wondering if the standard Performer might be a better torque choice. Thoughts???

05-30-2006, 10:17 PM	#2
clay68c10 Senior Member Join Date: Aug 2004 Location: Centennial, CO Posts: 2,979	Re: Intake question for the engine guru's.... The regular Performer will probably match the rpm range of the cam better. I had a 268 comp in a 350 way back and it ran pretty strong. I was running a Weiand stealth intake. __________________ ClusterTruck: 68 C10 Bought in 89, wrecked in 03. Slow low $ rebuild started '17. 6.0 & TKO http://67-72chevytrucks.com/vboard/s...d.php?t=788602 93 K1500 Short Step, 350, NV4500, EBL flash ECU. Vortec heads & roller cam someday... 05 Jeep Wrangler Unlimited. 3” lift & 6-speed 02 E320 the insurance total “free car” 13 Tahoe LTZ

05-30-2006, 10:18 PM	#3
Gray Ghost Senior Member Join Date: Sep 2004 Location: Terrell, TX Posts: 1,967	Re: Intake question for the engine guru's.... The RPM kicks in about 2500 rpm iirc....the performer starts at 1500 and will give you more low end torque. I had Vortec heads on mine and wasn't that impressed, there's better heads out there for sure. The 268 cam will help a bunch. __________________ Kelly '05 GMC Sierra SLE Z71 Bone stock except for new bed rail caps.

05-30-2006, 10:31 PM	#4
Daubs Registered User Join Date: Jan 2005 Location: Eastern Nebraska Posts: 611	Re: Intake question for the engine guru's.... I'm just a slight motor head, but checking the edelbrock web site shows the following: PERFORMER (idle-5500 rpm) PERFORMER RPM (1500-6500 rpm) If you switch to Vortec heads you are going to have to get new intake to match. I'd stick with the standard Performer if you want more low end. The 268H lists as "Good street performance with stock converter, choppy idle." That cam is going to have Duration @0.05 of 218 & 218. That is going to push your power sweet spot higher in RPM range (less low end grunt). For more low end grunt you might look at following cams: Dual Energy 255DEH Cam: "Good torque, good mileage. Good RV & towing cam. Smooth idle" High Energy/Marine 260H Cam: "Vans, pickups, 4WD & towing, in 350 c.i., good idle, strong mid range torque" High Energy 252H Cam: "Strong torque, excellent mileage for 327-400 c.i., has smooth idle, likes high axle ratios" I made mistake of getting a cam that was too "big" for my 82 4x4 manual tranny truck with 3.08 rear end. No low end grunt. Ended up pulling that cam and putting something close to 252 grind in. Much better. What tranny and rear end are you planning to run? Is this 2 wheel or 4 wheel drive? What do you want to do with truck? __________________ '72 Chevy K-20 Crate 350, SM465, 4.10's

05-30-2006, 10:35 PM	#5
tx69gmc Registered User Join Date: Nov 2005 Location: Denton,TX Posts: 61	Re: Intake question for the engine guru's.... Thanks for the info. I have the TH350 with 3.73's in the rear. Because of the tranny and gears, I am looking to get the most low end as that is most likely where most of my time will be spent. This is not a daily driver and I am looking for a seat of the pants weekend cruiser.

05-30-2006, 10:44 PM	#6
Daubs Registered User Join Date: Jan 2005 Location: Eastern Nebraska Posts: 611	Re: Intake question for the engine guru's.... You might think about swapping out the RPM for a standard Performer and keep the Edelbrock 650 carb and stock heads / cam. I'm assuming you got the base level crate motor, the 260 HP version (part number 10067353 -- not the 290 HP version) What size tires are you running? Two or four wheel drive? __________________ '72 Chevy K-20 Crate 350, SM465, 4.10's

05-30-2006, 10:55 PM	#7
tx69gmc Registered User Join Date: Nov 2005 Location: Denton,TX Posts: 61	Re: Intake question for the engine guru's.... Yep. Base level crate 350. 2WD with 17's. I have most of the parts already but might need to swap out intake and cam. I also currently have long tube headers which are hanging too low with my front end being dropped. I have heard a lot about the Ram Horn Manifolds. What do you guys think?

05-30-2006, 10:55 PM	#8
boot85 71 Chevy Join Date: May 2006 Location: Madison, Wisconsin Posts: 83	Re: Intake question for the engine guru's.... I agree with Daubs, if you are after a low end torque motor you have to forget about the fab of the high lift cams and big valve heads. The truth of the matter is that for low end torque you want a low duration cam and small valves. The heads do not have to be top of the line either, the stock heads would be just fine with some new valve seats and new guides. As for the intake any of the Edlebrock Proformer Series would work just fine. Since they are a dual plane intake and that design is for idle up to about 5500 RPM. Hope this helps

05-30-2006, 11:04 PM	#9
boot85 71 Chevy Join Date: May 2006 Location: Madison, Wisconsin Posts: 83	Re: Intake question for the engine guru's.... After seeing your last post, another thing to think about if you really are after a low end toque engine is the exhuast. The larger exhuast you have the more you are taking away from the low end torque. For example if you have 1 3/4' exhuast you are going to be robbing your low end torque. You would be better suited to go with a smaller primary rather than a larger one. If I were you I would go with the tried and true chevy Ram Horns, you will surely get the best bang for your buck. Even though they look as pretty as a header they are way more functional for your application.

05-30-2006, 11:08 PM	#10
Daubs Registered User Join Date: Jan 2005 Location: Eastern Nebraska Posts: 611	Re: Intake question for the engine guru's.... Base level 350 is the 260HP version, same engine as mine (it's on engine stand now...waiting on a few parts before install). You might be able to get away with bigger cam because of your auto tranny. But be careful. Boot85 is right, smaller valves and lower duration cam, smaller tube headers (and smaller 4 barrel carb) give you better low end grunt. I would seriously consider starting with Performer intake and keeping everything else as you have it (stock heads, cam, Edelbrock 650 carb). You would really hate yourself if you spent all that $$ on heads, cam, etc., and didn't have the low end you want. __________________ '72 Chevy K-20 Crate 350, SM465, 4.10's

05-30-2006, 11:11 PM	#11
Gray Ghost Senior Member Join Date: Sep 2004 Location: Terrell, TX Posts: 1,967	Re: Intake question for the engine guru's.... Thanks for the correction on the RPMs...should looked it up, too tired to be doing this from memory. __________________ Kelly '05 GMC Sierra SLE Z71 Bone stock except for new bed rail caps.

05-31-2006, 10:54 AM	#12
NewKid Registered User Join Date: Aug 2005 Location: OCEAN SHORES WASHINGOTN Posts: 57	Re: Intake question for the engine guru's.... There is an article at this site that shows a vortec cast iron head that is 23 degree fastburn vortec cast iron that will use 4 and 6 bolt intake manifolds. http://popularhotrodding.com/enginem...0511em_vortec/ __________________ 83 GMC Vandura 1 Ton 84 Chevy S-10 4x4 Durango 84 Ford 1 ton Cargo van

05-31-2006, 09:05 PM	#14
72MARIO Registered User Join Date: Nov 2000 Location: Huntsville Ontario Canada Posts: 4,052	Re: Intake question for the engine guru's.... I have the performer RPM on my 67 an would really like to swap out to a perfromer just to see the diffirence. I would like more bottom end power because all the driving I do needs the get go. I also am not very happy with the millage I am getting (12 MPG with a 700R). It's a basic 355 using the 327/350HP cam I thinkit's a 447/447 lift. Thinking it's time to try the swap. __________________ 1968 Suburban numbers matching all original truck now equipped with 6.0/4L80 on Accuair http://67-72chevytrucks.com/vboard/s...d.php?t=625017 1967 C/20 6.0/4L80 Roofing Truck 1990 V2500 Suburban "Plow Truck" 2005 TAHOE DD

05-31-2006, 09:23 PM	#16
glock35ipsc Next project: 1970 K10 Join Date: Feb 2004 Location: Fort Collins, Colo 80524 Posts: 6,685	Re: Intake question for the engine guru's.... I have the 260hp crate motor in the 68 too. I run a standard Performer, 650 Edelbrock, and a Comp 268H. At that time, I had the manual 3-speed with 3.73's. Ran great and had awesome low end. When the 68 goes back together, it will have the same set-up, but with a TH350 and about a 2200-2400 rpm converter. __________________ *Bob* 1970 Chevy K10 LWB "Goldie" 350/TH350 *next project!!* 1981 Chevy C10 LWB 355/TH350 - My son's truck LS SWAP FORUM! Tons of LS swap info here! PLEASE CLICK HERE TO SUPPORT THE GREATEST BOARD ON THE NET! CLICK HERE FOR THE FAQ INDEX by KRUE

05-31-2006, 10:07 PM	#17
Chevrolet4x4s Registered User Join Date: Nov 2005 Location: WV Posts: 227	Re: Intake question for the engine guru's.... Performer EPS is optimised to Performer series carbs and showed according to Edelbrock about 7hp and 9 ftlbs over the standard Performer intake.A Performer EPS will really wake up a sbc vs the stock intake. Shane __________________ 1993 K1500 350 5 speed 1985 K10 Silverado Vortec 406 5 speed (in body shop) "I been drivin' this '85 pickup truck Them buddies of mine call it a bucket of rust She's a little beat up but she still runs like the wind Yeah, kinda like me I been banged and bruisedBeen around the block a time or two But I'm runnin' like new goin' places I never been No, I ain't broke I'm just broken in" 1963 Dodge Townwagon(its amazng what 30 years and zero miles will do to a vehicle ) Member#20327



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05-31-2006, 10:57 PM	#18
71chevytruckguy Registered User Join Date: Jul 2005 Location: Kernersville, NC Posts: 599	Re: Intake question for the engine guru's.... i've got a 305 in my '69 with a comp 268h cam with a vintage offenhauser daul port intake intake, carb adapter, a rebuilt q-jet, flat tops pistons, and headers. i've a 4 spd saginaw trans with 3.73 gears out back. it really doesn't start to pull untill u get the engine up to 2000rpm then it really comes to life. i like it and if work fine for me. gets 11 mpg on 93 octane. chris. __________________ its a work in progess. 71 c-10 lwb, in the middle of frame off restoration. 69 c-10 swb, drag truck, 406 sbc, balanced, comp 292 cam, ported, polished, gasket matched, and bowl blended pro comp 210cc heads, 2.02/1.60 ferrea valves,1.6 roller rockers, re curved hei with msd 6al box, 2-step rev limter, accel 300+ wires, ported victor jr intake, holley 750 double pumper carb, dynomax 1 5/8 headers, 4 spd munci m-20 with super case and iron midplate, mr. gasket vertigate shifter, 5.38 pro gears with full spool, 33 spline moser axles and c-clip elimators, line-loc, 5 gal fuel cell, holley blue pump. 7.807 @ 88.37mph 1.60 60FT 80 g-20 van, tow rig, cammed 305, th350, 10 bolt 88 jeep wrangler, dd, 258, ax-15 swap, 4.5" lift, 33x12.50's, lockers, 3.55's

06-01-2006, 08:10 AM	#19
Chevrolet4x4s Registered User Join Date: Nov 2005 Location: WV Posts: 227	Re: Intake question for the engine guru's.... RV cams are good for trucks __________________ 1993 K1500 350 5 speed 1985 K10 Silverado Vortec 406 5 speed (in body shop) "I been drivin' this '85 pickup truck Them buddies of mine call it a bucket of rust She's a little beat up but she still runs like the wind Yeah, kinda like me I been banged and bruisedBeen around the block a time or two But I'm runnin' like new goin' places I never been No, I ain't broke I'm just broken in" 1963 Dodge Townwagon(its amazng what 30 years and zero miles will do to a vehicle ) Member#20327

06-01-2006, 08:43 AM	#20
AKChevyman Chevy Forever Join Date: Jun 2005 Location: Dalzell SC Posts: 314	Re: Intake question for the engine guru's.... Just to throw another idea out there what about and airgap intake that may help with the low end torque. Just a suggestion. __________________ My first love 1971 C20 Hugger orange Getting face lift and heart transplant .30 402 BB /TH400 and GV Wifes car 1969 Chevelle SS 396 325hp/TH400 Factroy A/C Automatic w/ Floor shift console. restored.

06-01-2006, 09:42 AM	#21
Daubs Registered User Join Date: Jan 2005 Location: Eastern Nebraska Posts: 611	Re: Intake question for the engine guru's.... Air gaps are pretty darn cool. But I've heard they don't work good in cooler / cold weather environments. Tough time warming up the engine and carb with the air gap. In a daily driver I'd still stick with the Performer (std) __________________ '72 Chevy K-20 Crate 350, SM465, 4.10's

06-01-2006, 09:57 AM	#22
70c10 67-72 Addict! Join Date: Feb 2002 Location: The TAX State! Posts: 7,857	Re: Intake question for the engine guru's.... I don't see anything wrong with the RPM intake with that cam. I would use about a 2500 stall converter. Those heads are good to about .470 lift and the 268 has more than that plus you are adding 1.6 rockers will push it higher so you will need to get the heads setup for that extra lift. Another thing you could do is change your gear ratio since you are running such a tall tire. __________________ Jim 1970 C/10 Fleetside w/Ghost Flames Lowered 4.5" front and 4" rear (Raked) 355/350 Turbo w/shift kit 10" Redneck Performance Verter w/2500 stall Hooker Super Comps part#2808-1 Performer RPM Air-Gap 12 Bolt w/3:73 gears- Eaton Posi Comp Cams XE262 with 1.6 Crane Energizers, Road Demon 625 and Brodix IK 180 heads Last edited by 70c10; 06-01-2006 at 10:13 AM.

06-01-2006, 12:02 PM	#24
Jason915 Registered User Join Date: Jan 2005 Location: Colorado Springs Posts: 693	Re: Intake question for the engine guru's.... I went from a L82 cam and a RPM intake to an EPS and Comp 4x4 cam because the truck would't tow very good at all it had great power after 2500 RPM but didn't have good "truck" low end. Now with the EPS and 4x4 cam it has a tremendious amount of low end power I would have never thought that a 355 with 2.02 X1.60 valves would have this much low end power as this motor has now. The RPM intakes are not for trucks trucks they are designed for cars that are 3600# or lighter. __________________ 1971 GMC K1500 SWB Fleetside, 4" skyjacker softride and, 14 Bolt FF, HD Dana 44 4.10's 1970 K5 TBI conversion lifted etc SOLD 1968 C20 camper truck SOLD “To ban guns because criminals use them is to tell the innocent and law-abiding that their rights and liberties depend not on their own conduct, but on the conduct of the guilty and the lawless.” Jeff Snyder

06-01-2006, 12:45 PM	#25
c10crazy Like a Rock! Join Date: May 2002 Location: USA Posts: 1,092	Re: Intake question for the engine guru's.... jason915, I bet your new power came from the cam mostly!. The 4x4 cam is way better technology. I have never heard RPM intakes are designed for the "specific weight" of a vehicle. They are designed for the RPM usage. __________________ 69 LWB Runs great - work in progress Mess with me and you mess with the whole trailer park!

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