Is it possible to swap 305 TBI heads for 305 TPI heads??
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Is it possible to swap 305 TBI heads for 305 TPI heads??
I have an 89 Formula w/ a 305 TPI in it. My T/A has a 305 TBI and my valve seals r bad and was wondering if its possibel to swap TBI heads for TPI heads? is there a diff. between the 2 sets?
Or does anyone know what type of aftermarket heads will fit on my 305 by any chance?
Or does anyone know what type of aftermarket heads will fit on my 305 by any chance?
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The 305 TPI heads will bolt right on a TBI engine. Putting TBI heads on a TPI engine is a step in the wrong direction.
The 305 TPI heads are about the best choice for a 305. Anything aftermarket wouldn't be made specifically for a 305 (350 is the hot market there, and bigger is becoming the norm), and wouldn't make sense unless you were doing a whole lot more to the engine and car for a full-out race-dedicated set-up.
The 305 TPI heads are about the best choice for a 305. Anything aftermarket wouldn't be made specifically for a 305 (350 is the hot market there, and bigger is becoming the norm), and wouldn't make sense unless you were doing a whole lot more to the engine and car for a full-out race-dedicated set-up.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
no i want to take the TPI heads and put them on my TBI engine. But i wasnt shure if it was possible and if thats a step in the better direction.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
you wont gain anything and you may not lose anything but have a better chance of losing power if doing so. yes theyll fit as long as theyre both 87+style. changing seals is easier than you think and will probably give out soon on the other heads too due to age. they all fail at one time or another and its always sooner than later just change them with some nice felpros and dont worry for a long time.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
you wont gain anything and you may not lose anything but have a better chance of losing power if doing so. yes theyll fit as long as theyre both 87+style. changing seals is easier than you think and will probably give out soon on the other heads too due to age. they all fail at one time or another and its always sooner than later just change them with some nice felpros and dont worry for a long time.
#6
Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
I think that if you are going to swap the heads, by all means do so, but be sure to put new valveseals on the heads you are putting on. I wouldnt pull heads to replace valve seals, but i would certainly pull lo3 heads in favor of
lb9 heads.
lb9 heads.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
ok i appreciate all the help. i was just wondering if i did would i gain a lil more power but as it sounds they r the same. but if i do pull the lo3 heads i was gunna do seals and have them re-maned and ported out. also how do u trun an egr valve off? i cut my cat out and i still have all the smog lines hanging around and when i get my headers installed will they turn it off or do i have to my self?
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
ok i appreciate all the help. i was just wondering if i did would i gain a lil more power but as it sounds they r the same. but if i do pull the lo3 heads i was gunna do seals and have them re-maned and ported out. also how do u trun an egr valve off? i cut my cat out and i still have all the smog lines hanging around and when i get my headers installed will they turn it off or do i have to my self?
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
is the "059" casting vortec heads the numbers on the bottom of the heads? do u know where i could possibly find a set of those and an intake for that matter. i have an edlebrock RPM Performer Intake mainifold that i picked up to go along with my camshaft. so all im really looking for is heads..
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
is the "059" casting vortec heads the numbers on the bottom of the heads? do u know where i could possibly find a set of those and an intake for that matter. i have an edlebrock RPM Performer Intake mainifold that i picked up to go along with my camshaft. so all im really looking for is heads..
Vortec heads REQUIRE a vortec specific intake. They only have 8 bolts and they enter the heads straight down through the intake.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Well, the 059 IS the number under the heads, but it is also the last 3 of the casting number. 059 heads came on the 1996-1999 chevy truck 305s and the 1996-2002 fullsize express/savana vans. They were also used on marine 305 engines. I see them turn up on ebay often for not much money. People forget to winterize the blocks of marine engines, trashing the block, and the heads are often not hurt.
Vortec heads REQUIRE a vortec specific intake. They only have 8 bolts and they enter the heads straight down through the intake.
Vortec heads REQUIRE a vortec specific intake. They only have 8 bolts and they enter the heads straight down through the intake.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Non-Vortec (I know its a TPI, but you get the idea)
Vortec
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
ok now i understand! thanks for all your help. ill see what i can find here at one of the local junkyards. i was also told that u can put a set of 350 heads on a 305? I don't know if thats true tho because 350 pistons r bigger and i was told that u can actually blow 350 heads off a 305 because the openings r different sizes causing them not to seal when the piston comes up for the compression stroke? I'm just wondering cause i have a set of 350 trick- flow heads in the basement that i'm wondering what to do with. They have 2" intake valves that r stainless steel. came off a 350 engine that ran off propane that was in a generator. Useable or not?
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
350 heads are definitely useable on a 305. Physically, they bolt right up and seal without any problems. The only issue with using a 350 head is you lose a lot of compression since almost all 305 heads use a 58 cc chamber, and most 350 heads are in the 64-76 cc range on the chambers. If you took them to a machine shop and had them milled down to 58 cc chambers, they'd work great. Otherwise I wouldn't do it since the lowered compression will cost you a good bit of power. The GM 113 casting, aluminum vette heads are great to use on a 305. They already have 58 cc chambers and flow great on a 305. You can have the EGR function turned off with a custom PROM chip. You can also run without the EGR with the existing PROM without really hurting anything, but you'll probably get a "check engine" light. In fact, if you did decide to use the 113 heads, it'd be a good idea to have the EGR function turned off anyways since those heads don't have the EGR passage in them. The vettes used an external EGR system that's plumbed into one of the exhaust manifold tubes.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
but if i do pull the lo3 heads i was gunna do seals and have them re-maned and ported out. also how do u trun an egr valve off? i cut my cat out and i still have all the smog lines hanging around and when i get my headers installed will they turn it off or do i have to my self?
Why not have the TPI heads ported and install better springs, then put them on your engine? You'll have less downtime that way.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Im not the only one who takes their cats off their f-bodies to give them a lil extra kick. So if your going to yell at me, then go give everyone else grief as well. And u cant run a cat when u run race gas anyhow so whats the point of putting a cat on my street/strip car when i use racing gas in it when i go to the track??? everyone knows racing gas burns hotter which makes the material inside catylitc converters melt down and plug solid. And by the way Michigan doesnt enforce the "smog emissions" act like all the other states do. Unlike California and Flordia, Michigan does not "require" emissions test on cars.
Last edited by TADailyDriver; 03-10-2008 at 02:58 PM.
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Kevin isn't ragging on you personally, so don't take it personally. What he says is true. Whether or not Michigan does emissions inspections, the laws you are violating by removing emissions equipment on a street driven car are Federal, not state or local. Other people doing it doesn't make it right for you.
Running a TPI engine on race gas is a complete waste of money. Spend it on something that will produce real results. Even if you run it, what you say regarding its effect on the catalytic converter is still not true.
If you're building a race car, build a race car. If you're building a street car, build a street car. If you're building a street/strip car, it comes in that order.
Since you're talking about factory heads, and going back to the original premise, changing heads because of bad valve seals, none of this sounds like a purpose-built project justifying race gas.
And, for the record, there's no such thing as "H.O. TBI", at least from the factory.
Running a TPI engine on race gas is a complete waste of money. Spend it on something that will produce real results. Even if you run it, what you say regarding its effect on the catalytic converter is still not true.
If you're building a race car, build a race car. If you're building a street car, build a street car. If you're building a street/strip car, it comes in that order.
Since you're talking about factory heads, and going back to the original premise, changing heads because of bad valve seals, none of this sounds like a purpose-built project justifying race gas.
And, for the record, there's no such thing as "H.O. TBI", at least from the factory.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
ok well im srry for my little outburst. I was told by a very good mechanic that ive know for many years that u arent suppose to run race gas with a catlaytic converter as it will cause them to plug due to the extreme heat. but everyone has their opinons i suppose. Anyway, i was also told that my engine is a High Output 305 due to the fact that it has a bigger harmonic balancer. But yet again people dont know everything and they do make mistakes so again correct me if im wrong. And i was only asking about head swappage not just because my valve seals r bad but because i know TPI engines r better then my TBI and so i figured the heads were much better and could benefit my engine. But again im srry if i affend anyone and im only on here to try and learn what i can as i do my build up of my car. So i thank everyone for thier help so far answering my questions.
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Many race fuels are leaded, and they will kill a catalytic converter. It's from coating, though, not excessive heat. The typical higher octane of race gas can actually slow a car down if the compression ratio isn't high enough to warrant the octane.
TPI heads will out-flow TBI heads. As Fast355 said, though, the TBI heads are better below a certain RPM range and valve lift. In order to get any improvement with TPI heads on a TBI engine, you have to do other things like cam and exhaust, so just the heads won't make a difference and may actually hurt, as mentioned.
From the factory, "HO" was only used on 3rd gens with the "L69" carb'd 305 engine, 1983 to 1985 (a few in 1986, but statistically insignificant). It made 190 HP, your stock LO3 made 170. The size of the damper doesn't mean anything, as it varied over the years (for reasons that show absolutely no pattern that I can see). There were TPI offerings that made more than 190 HP, but the factory never called them "HO".
There are a lot of myths and wifes' tales out there. This Board has been an invaluable resource for weeding out the ones I've swallowed.
TPI heads will out-flow TBI heads. As Fast355 said, though, the TBI heads are better below a certain RPM range and valve lift. In order to get any improvement with TPI heads on a TBI engine, you have to do other things like cam and exhaust, so just the heads won't make a difference and may actually hurt, as mentioned.
From the factory, "HO" was only used on 3rd gens with the "L69" carb'd 305 engine, 1983 to 1985 (a few in 1986, but statistically insignificant). It made 190 HP, your stock LO3 made 170. The size of the damper doesn't mean anything, as it varied over the years (for reasons that show absolutely no pattern that I can see). There were TPI offerings that made more than 190 HP, but the factory never called them "HO".
There are a lot of myths and wifes' tales out there. This Board has been an invaluable resource for weeding out the ones I've swallowed.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Many race fuels are leaded, and they will kill a catalytic converter. It's from coating, though, not excessive heat. The typical higher octane of race gas can actually slow a car down if the compression ratio isn't high enough to warrant the octane.
TPI heads will out-flow TBI heads. As Fast355 said, though, the TBI heads are better below a certain RPM range and valve lift. In order to get any improvement with TPI heads on a TBI engine, you have to do other things like cam and exhaust, so just the heads won't make a difference and may actually hurt, as mentioned.
From the factory, "HO" was only used on 3rd gens with the "L69" carb'd 305 engine, 1983 to 1985 (a few in 1986, but statistically insignificant). It made 190 HP, your stock LO3 made 170. The size of the damper doesn't mean anything, as it varied over the years (for reasons that show absolutely no pattern that I can see). There were TPI offerings that made more than 190 HP, but the factory never called them "HO".
There are a lot of myths and wifes' tales out there. This Board has been an invaluable resource for weeding out the ones I've swallowed.
TPI heads will out-flow TBI heads. As Fast355 said, though, the TBI heads are better below a certain RPM range and valve lift. In order to get any improvement with TPI heads on a TBI engine, you have to do other things like cam and exhaust, so just the heads won't make a difference and may actually hurt, as mentioned.
From the factory, "HO" was only used on 3rd gens with the "L69" carb'd 305 engine, 1983 to 1985 (a few in 1986, but statistically insignificant). It made 190 HP, your stock LO3 made 170. The size of the damper doesn't mean anything, as it varied over the years (for reasons that show absolutely no pattern that I can see). There were TPI offerings that made more than 190 HP, but the factory never called them "HO".
There are a lot of myths and wifes' tales out there. This Board has been an invaluable resource for weeding out the ones I've swallowed.
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Is that a roller lifter version of that cam? If not, take it back and look at a factory roller type cam. I've never heard glowing reports about Edelbrock cams, but I also haven't heard much about their roller versions. Comp, Lunati, Crane, all make good modern roller grinds that will out-run the typical Edelbrock off-the-shelf cam.
The overall plan is fine. It's actually the typically recommended route to improving performance.
Most any replacement cat now days will be high flow, but the TBI exhaust to a part is restrictive. So, replacing all of it with '86-'90 TPI single-cat application stuff is much better than just replacing the TBI-size cat.
Race gas really isn't going to make a difference. Pump gas will be fine.
The torque converter stall should match the cam and intake (well, the cam and intake should match each other). Whatever the cam manufacturer says is the cam "powerband", figure on 500-1000 RPM more stall than that. Error toward the higher side since most any SBC cam assumes a 350, and a 305 needs more stall for the same cam than a 350 would.
The overall plan is fine. It's actually the typically recommended route to improving performance.
Most any replacement cat now days will be high flow, but the TBI exhaust to a part is restrictive. So, replacing all of it with '86-'90 TPI single-cat application stuff is much better than just replacing the TBI-size cat.
Race gas really isn't going to make a difference. Pump gas will be fine.
The torque converter stall should match the cam and intake (well, the cam and intake should match each other). Whatever the cam manufacturer says is the cam "powerband", figure on 500-1000 RPM more stall than that. Error toward the higher side since most any SBC cam assumes a 350, and a 305 needs more stall for the same cam than a 350 would.
Last edited by five7kid; 03-11-2008 at 03:59 PM.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Is that a roller lifter version of that cam? If not, take it back and look at a factory roller type cam. I've never heard glowing reports about Edelbrock cams, but I also haven't heard much about their roller versions. Comp, Lunati, Crane, all make good modern roller grinds that will out-run the typical Edelbrock off-the-shelf cam.
The overall plan is fine. It's actually the typically recommended route to improving performance.
Most any replacement cat now days will be high flow, but the TBI exhaust to a part is restrictive. So, replacing all of it with '86-'90 TPI single-cat application stuff is much better than just replacing the TBI-size cat.
Race gas really isn't going to make a difference. Pump gas will be fine.
The torque converter stall should match the cam and intake (well, the cam and intake should match each other). Whatever the cam manufacturer says is the cam "powerband", figure on 500-1000 RPM more stall than that. Error toward the higher side since most any SBC cam assumes a 350, and a 305 needs more stall for the same cam than a 350 would.
The overall plan is fine. It's actually the typically recommended route to improving performance.
Most any replacement cat now days will be high flow, but the TBI exhaust to a part is restrictive. So, replacing all of it with '86-'90 TPI single-cat application stuff is much better than just replacing the TBI-size cat.
Race gas really isn't going to make a difference. Pump gas will be fine.
The torque converter stall should match the cam and intake (well, the cam and intake should match each other). Whatever the cam manufacturer says is the cam "powerband", figure on 500-1000 RPM more stall than that. Error toward the higher side since most any SBC cam assumes a 350, and a 305 needs more stall for the same cam than a 350 would.
Last edited by TADailyDriver; 03-11-2008 at 05:16 PM.
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The best way is by the description provided by the manufacturer. If you have the p/n, you should be able to tell from Edelbrock's on-line information. (Sorry, I can't access facebook from the computer I'm using right now.)
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
how do i post pics on the reply page like that guy did above?
----------
This is right from the edelbrock website:
Important Application Information
Performer RPM and Performer RPM Hydraulic Roller are for street high-performance and racing applications only — not for heavy vehicles. Use with Edelbrock Performer RPM heads (or other aftermarket heads), adjustable valvetrain components, screw-in studs, high-performance adjustable rocker arms and at least 9.5:1 compression ratio. Headers, high-energy ignitions, lower-than-stock rear gearing and a high-performance torque converter (in auto. transmission equipped vehicles) are necessary.
----------
This is right from the edelbrock website:
Important Application Information
Performer RPM and Performer RPM Hydraulic Roller are for street high-performance and racing applications only — not for heavy vehicles. Use with Edelbrock Performer RPM heads (or other aftermarket heads), adjustable valvetrain components, screw-in studs, high-performance adjustable rocker arms and at least 9.5:1 compression ratio. Headers, high-energy ignitions, lower-than-stock rear gearing and a high-performance torque converter (in auto. transmission equipped vehicles) are necessary.
Last edited by TADailyDriver; 03-11-2008 at 05:54 PM. Reason: Automerged Doublepost
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Im not the only one who takes their cats off their f-bodies to give them a lil extra kick. So if your going to yell at me, then go give everyone else grief as well. And u cant run a cat when u run race gas anyhow so whats the point of putting a cat on my street/strip car when i use racing gas in it when i go to the track??? everyone knows racing gas burns hotter which makes the material inside catylitc converters melt down and plug solid. And by the way Michigan doesnt enforce the "smog emissions" act like all the other states do. Unlike California and Flordia, Michigan does not "require" emissions test on cars.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Also its been proven that NASCAR car's engines dump out more harmful emmissons in 1 race then my car would in an entire year lol
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3702 - that's what we needed. The description you posted is the general information about that series of cam.
The 3702 is flat tappet. You'll need new pushrods and timing set in order to use it (I assume it came with new lifters). Lift is lame, too. Might as well spent $230 on a roller camshaft that allows you to reuse the lifters & pushrods (might need to replace the timing set just for peace of mind's sake). Or, $75-$150 for a ZZ4 or LT1 take-out cam from eBay, racingjunk or craigslist.
To post pics, click on the "manage attachments" button when you are starting a new thread or replying to an existing thread.
The 3702 is flat tappet. You'll need new pushrods and timing set in order to use it (I assume it came with new lifters). Lift is lame, too. Might as well spent $230 on a roller camshaft that allows you to reuse the lifters & pushrods (might need to replace the timing set just for peace of mind's sake). Or, $75-$150 for a ZZ4 or LT1 take-out cam from eBay, racingjunk or craigslist.
To post pics, click on the "manage attachments" button when you are starting a new thread or replying to an existing thread.
Last edited by five7kid; 03-12-2008 at 12:43 AM.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
3702 - that's what we needed. The description you posted is the general information about that series of cam.
The 3702 is flat tappet. You'll need new pushrods and timing set in order to use it (I assume it came with new lifters). Lift is lame, too. Might as well spent $230 on a roller camshaft that allows you to reuse the lifters & pushrods (might need to replace the timing set just for peace of mind's sake). Or, $75-$150 for a ZZ4 or LT1 take-out cam from eBay, racingjunk or craigslist.
To post pics, click on the "manage attachments" button when you are starting a new thread or replying to an existing thread.
The 3702 is flat tappet. You'll need new pushrods and timing set in order to use it (I assume it came with new lifters). Lift is lame, too. Might as well spent $230 on a roller camshaft that allows you to reuse the lifters & pushrods (might need to replace the timing set just for peace of mind's sake). Or, $75-$150 for a ZZ4 or LT1 take-out cam from eBay, racingjunk or craigslist.
To post pics, click on the "manage attachments" button when you are starting a new thread or replying to an existing thread.
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Stock flat-tappet length rods. You don't need anything fancy.
You really should reconsider the cam, though. You'll make more power with a more modern grind, and it'll behave better. Those Edelbrock cams are over-priced and under-performing. "I already have it" is the absolute worst reason to use it.
You really should reconsider the cam, though. You'll make more power with a more modern grind, and it'll behave better. Those Edelbrock cams are over-priced and under-performing. "I already have it" is the absolute worst reason to use it.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Stock flat-tappet length rods. You don't need anything fancy.
You really should reconsider the cam, though. You'll make more power with a more modern grind, and it'll behave better. Those Edelbrock cams are over-priced and under-performing. "I already have it" is the absolute worst reason to use it.
You really should reconsider the cam, though. You'll make more power with a more modern grind, and it'll behave better. Those Edelbrock cams are over-priced and under-performing. "I already have it" is the absolute worst reason to use it.
ok well i also have a 2103 Edelbrock cam that my dad bought for his 350 a couple years ago that was never installed and is still sitting in the box. Is that a better choice or should i just take back the 3702 and get something better? But i also want a cam that will give the engine that "rough idle" sound.
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I wouldn't use either one of them. The lift is just pathetic, the grind leaves a lot of power on the table while making the whole engine peakier - not good for a street/strip car.
Seriously, I'd rather see you spend twice as much on the cam now, keep the factory roller set-up, and gain more in the low end while making more power at the top. Neither of those Edelbrock cams would do the RPM intake justice, while the more sophisticated grinds available now would bring smiles both on the street and track.
An example would be http://store.summitracing.com/partde...8&autoview=sku . There are probably other good choices out there, I was just looking for reasonable lift with more duration and a modern grind. You will absolutely have to have new valve springs for that cam, and the guides cut down for more valve travel (cutting the guides for positive-type valve stem seals is a good two-birds-with-one-stone way to get that) - easy to do when you've got the heads apart for the porting and rebuild.
Seriously, I'd rather see you spend twice as much on the cam now, keep the factory roller set-up, and gain more in the low end while making more power at the top. Neither of those Edelbrock cams would do the RPM intake justice, while the more sophisticated grinds available now would bring smiles both on the street and track.
An example would be http://store.summitracing.com/partde...8&autoview=sku . There are probably other good choices out there, I was just looking for reasonable lift with more duration and a modern grind. You will absolutely have to have new valve springs for that cam, and the guides cut down for more valve travel (cutting the guides for positive-type valve stem seals is a good two-birds-with-one-stone way to get that) - easy to do when you've got the heads apart for the porting and rebuild.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
well i think ill take ur advice and go with that comp cam. Im on a tight budget tho which means it prolly wont come to me until summer time. But ill still install that timing kit, shift kit, and headers. Anything else u can reccommend me to do?
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Its a 7801 Performer- Link True Rolling Timing Chain. Is that still compatible with that Comp Xtreme Series Cam?
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"For factory roller camshaft motors. Will not fit behind stock timing cover."
It won't fit the Edelbrock cams you have, actually.
It won't fit the Edelbrock cams you have, actually.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
So im taking back the Edelbrock Camshaft and buying the Comp Cam Xtreme Series. So now all i have to do it buy an aftermarket timing chain cover? anything else i need to know?
this is the cam im looking at:
Brand:COMP Cams Product Line:COMP Cams Xtreme Energy Camshafts Part Type:Camshafts Part Number: CCA-08-502-8 Cam Style: Hydraulic roller tappet Basic Operating RPM Range: 1,500-5,500 Intake Duration at 050 inch Lift: 218 Exhaust Duration at 050 inch Lift: 224 Duration at 050 inch Lift: 218 int./224 exh. Advertised Intake Duration: 269 Advertised Exhaust Duration: 276 Advertised Duration: 269 int./276 exh. Intake Valve Lift with Factory Rocker Arm Ratio: 0.495 in. Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.503 in. Valve Lift with Factory Rocker Arm Ratio: 0.495 int./0.503 exh. lift Lobe Separation (degrees): 112 Intake Valve Lash: 0.000 in. Exhaust Valve Lash: 0.000 in. Computer Controlled Compatible: No Grind Number: CS XR269HR-12 Quantity: Sold individually. Camshaft, Hydraulic Roller Tappet, Advertised Duration 269/276, Lift .495/.503, Chevy, Small Block, Each
but it said beg. year 1987 and ending year 1987. mines an 88 will it still fit?
this is the cam im looking at:
Brand:COMP Cams Product Line:COMP Cams Xtreme Energy Camshafts Part Type:Camshafts Part Number: CCA-08-502-8 Cam Style: Hydraulic roller tappet Basic Operating RPM Range: 1,500-5,500 Intake Duration at 050 inch Lift: 218 Exhaust Duration at 050 inch Lift: 224 Duration at 050 inch Lift: 218 int./224 exh. Advertised Intake Duration: 269 Advertised Exhaust Duration: 276 Advertised Duration: 269 int./276 exh. Intake Valve Lift with Factory Rocker Arm Ratio: 0.495 in. Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.503 in. Valve Lift with Factory Rocker Arm Ratio: 0.495 int./0.503 exh. lift Lobe Separation (degrees): 112 Intake Valve Lash: 0.000 in. Exhaust Valve Lash: 0.000 in. Computer Controlled Compatible: No Grind Number: CS XR269HR-12 Quantity: Sold individually. Camshaft, Hydraulic Roller Tappet, Advertised Duration 269/276, Lift .495/.503, Chevy, Small Block, Each
but it said beg. year 1987 and ending year 1987. mines an 88 will it still fit?
Last edited by TADailyDriver; 03-12-2008 at 10:56 PM.
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To be honest with you, I don't know what they mean by "Will not fit behind stock timing cover," or what timing cover will work. I'd say give Edelbrock a call (I quoted that from Summit's site, by the way - whether they could answer that question is a crap shoot.)
There's no difference between 1987 and 1988. Check the other listed applications, you're covered.
There's no difference between 1987 and 1988. Check the other listed applications, you're covered.
Last edited by five7kid; 03-13-2008 at 01:20 PM.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Well great news! theres a local car yard outside of town and the guy is willing to sell me a set of Vortec heads and the Intake manifold for 150 bucks! they r off a 1997 305. I found the timing cover kit i need and i should have that new comp cam ordered by the end of this week. Will be bringing the other one back soon! What type of valve springs should i go with for the heads? Anything u can think of that i may need just tell me! thanks
#39
Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Well great news! theres a local car yard outside of town and the guy is willing to sell me a set of Vortec heads and the Intake manifold for 150 bucks! they r off a 1997 305. I found the timing cover kit i need and i should have that new comp cam ordered by the end of this week. Will be bringing the other one back soon! What type of valve springs should i go with for the heads? Anything u can think of that i may need just tell me! thanks
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
he said he had 305, and 350 vortec assemblies laying around, and i already wrote down the casting numbers that i was given earlier so ill def make shure to check. i dont wanna get screwed outta a deal
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
If they are 059 castings, they are the ones you want for a 305. If they are 520 castings, they are roughly equivalent to the 081 TPI heads.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Ok ya i gotta call the guy tommrow and have him pull a set of 305 v. heads n intake then go and look at them. What type of valve springs should i run? Also will my throttle body setup fit right onto that intake? if not what will i have to do to make it fit.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Don't feel bad dude. He gets up on his soapbox about the tampering deal everytime someone posts anything about their cats or their smog pump system. I was giving him a hard time about it just a few weeks ago too. Whether something is legal or illegal doesn't always coincide with it being right. In other words, a lot of the laws that the tree-huggers have put into effect are completely retarded anyways. The smog pump and the cat on my car took a permanent vacation a long time ago. I guess if you live in a state like CA long enough, all those enviromental crackpots start to rub off on you, even if you're a car guy. Lol. If those dumbasses really want to clean up the air, they need to go after all the big industries that dump tons of crap into the air from smokestacks. Of course that'll never happen since they have the money to pay lobbyists to keep them off their backs. A few car hobbyists are hurting this planet's air about as much as a cloud of gnats. Ok, done ranting now.
In the meantime, I'm running 12 second ET's, getting 25+ miles per gallon on the highway, putting more than 350 horsepower to the wheels, and passing CA's tough smog test (including the visual) as clean as stock. When you can do the same, let me know. In the meantime, I'll be over here laughing as you try to find out of stock emissions devices when your state decides to start doing emissions tests.
Unleaded gas from the pump, will not harm your catalytic converter. Its only leaded gas that will hurt it.
#44
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Ok so for the Comp Cam Xtreme Energy Cam im looking at says its doesnt work w/ computer controlled Vehicles. I have a computer controlled Dist. so will it work with my car's engine or not.
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It's not the distributor, it's the computer that the cam may make unhappy.
Which cam, specifically?
Which cam, specifically?
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
Make CHEVROLET Engine Type V8 Engine Size 5.0L/305 Liter 5.0 CID 305 Beginning Year 1987 Ending Year 1988 Engine Family Chevy small block Gen I Camshaft Usage Street/StripAm i good to go???
#47
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I'm probably not the best person to answer about TPI (certainly not the one with a load of experience with it), but I don't think it would cause any problems.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
#49
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Oops, sorry, got this topic mixed up with another.
TBI is speed density, meaning the programing assumes certain things are true such as displacement, exhaust flow, cam timing, etc. Changing those things can throw off what it does based on what it sees.
The TBI forum would be a better place to get that answer.
TBI is speed density, meaning the programing assumes certain things are true such as displacement, exhaust flow, cam timing, etc. Changing those things can throw off what it does based on what it sees.
The TBI forum would be a better place to get that answer.
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Re: Is it possible to swap 305 TBI heads for 305 TPI heads??
ok well thanks for all your help, really appreciate it. and will keep u posted about my upgrades and progress.