So called 1st run SLP runners?
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Le Mans Master
Joined: Oct 2008
Posts: 9,758
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From: Houston Texas
So called 1st run SLP runners?
I bought these runners used so I have no history on them. The center runners were not siamesed. The other two were, you can tell they were cast that way. I have been told they are not SLP runners. They are Knock-offs*shrug*.What do you know about them? How will they flow? I siamesed the top as far as I could, 5" or so. I am going to see where my rpms fall off and maybe fully siamese them if needed.
Race Director
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From: Overland Park Kansas
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The said they never made anything other than the version being sold today.
Since no other manufacture name has been attached to this design, I'm assuming they're knock-offs. And, with a change in runner-config the makers were probably able to avoid patent infringement. That kind of business rarely lasts and is probably why these aren't made anymore.
Thread Starter
Le Mans Master
Joined: Oct 2008
Posts: 9,758
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From: Houston Texas
I might be the one who said this. After asking SLP (directly) about these runners, they replied along those lines. Basically, they said "Don't ask us, we didn't make those.
The said they never made anything other than the version being sold today.
Since no other manufacture name has been attached to this design, I'm assuming they're knock-offs. And, with a change in runner-config the makers were probably able to avoid patent infringement. That kind of business rarely lasts and is probably why these aren't made anymore.
The said they never made anything other than the version being sold today.
Since no other manufacture name has been attached to this design, I'm assuming they're knock-offs. And, with a change in runner-config the makers were probably able to avoid patent infringement. That kind of business rarely lasts and is probably why these aren't made anymore.
You said it I didn't want to incriminate you
Team Owner
Joined: Dec 2007
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I might be the one who said this. After asking SLP (directly) about these runners, they replied along those lines. Basically, they said "Don't ask us, we didn't make those.
The said they never made anything other than the version being sold today.
Since no other manufacture name has been attached to this design, I'm assuming they're knock-offs. And, with a change in runner-config the makers were probably able to avoid patent infringement. That kind of business rarely lasts and is probably why these aren't made anymore.
The said they never made anything other than the version being sold today.
Since no other manufacture name has been attached to this design, I'm assuming they're knock-offs. And, with a change in runner-config the makers were probably able to avoid patent infringement. That kind of business rarely lasts and is probably why these aren't made anymore.
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
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They are. Only 2-3 sets per year on eBay.
This looks like a nicer set.
(Accept, maybe, for the really thin wall left on the bottom of one of the runners. Is that where you're having problems getting it to seal?)
This looks like a nicer set.
(Accept, maybe, for the really thin wall left on the bottom of one of the runners. Is that where you're having problems getting it to seal?)
Last edited by GREGGPENN; Jul 2, 2009 at 01:22 AM.
Thread Starter
Le Mans Master
Joined: Oct 2008
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From: Houston Texas
WOW! all I need now is some hash marks and I could sell it on Ebay as a Grand Spark Corvette
Last edited by ch@0s; Jul 2, 2009 at 01:31 AM.
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Pro
Joined: Jun 2005
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From: USA
my vague recollection is that when the SLP runners first came out, only one pair on each side was siamesed, no kidding, and the science behind that was that the unsiamesed sets of runners would benefit lower rpm torque, and the siamesed runners would benefit higher rpms, and sorta average out the engine for overall better performance.
then after a while, both sets of runners on each half were siamesed.
I'm not making this up. this was way back when, when TPI first came out, and SLP was on the leading edge of TPI performance.
just my vague recollection.
then after a while, both sets of runners on each half were siamesed.
I'm not making this up. this was way back when, when TPI first came out, and SLP was on the leading edge of TPI performance.
just my vague recollection.
Burning Brakes
Joined: Nov 2004
Posts: 800
Likes: 3
From: Port Orange FL
my vague recollection is that when the SLP runners first came out, only one pair on each side was siamesed, no kidding, and the science behind that was that the unsiamesed sets of runners would benefit lower rpm torque, and the siamesed runners would benefit higher rpms, and sorta average out the engine for overall better performance.
then after a while, both sets of runners on each half were siamesed.
I'm not making this up. this was way back when, when TPI first came out, and SLP was on the leading edge of TPI performance.
just my vague recollection.
then after a while, both sets of runners on each half were siamesed.
I'm not making this up. this was way back when, when TPI first came out, and SLP was on the leading edge of TPI performance.
just my vague recollection.
Roy
Le Mans Master
Joined: Feb 2003
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From: Chicago IL
SLP is the only company I know of that made them like that.
The first batches of runners were actually pretty good quality. Since the tooling is very expensive, the dies became looser as time went on and the last few batches were so bad, I am surprised SLP even sold them.
The first batches of runners were actually pretty good quality. Since the tooling is very expensive, the dies became looser as time went on and the last few batches were so bad, I am surprised SLP even sold them.
Thread Starter
Le Mans Master
Joined: Oct 2008
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From: Houston Texas
I just took them off gain because they are leaking. I had to helicoil the bolt holes and plan on using Fel Pro gaskets. The TPIS gaskets fit a little higher and they don't seal well.
Race Director
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From: Overland Park Kansas
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To settle the debate, someone else call SLPONLINE.com and ask if runners used to be made w/o a divider in 2 of the 4 tubes.
I called in fall 2007. At that time, the tech line was answered by a co-owner of the company. He said SLP never made them w/o dividers.
But hey...You never know. He may have been throwing a few back that day!
FYI...The subject cam up like this. I called and asked why dividers where so small (e.g., 1.5"). Their reply was hours and hours of testing provide that to be the optimal config. A few days later I saw two sets w/o dividers in two tubes. Because they were the same, I assumed they were cast that way. (Also, I've seen more sets since then.)
I called back and asked about the tech/thinking with their original design that didn't have dividers in two legs. He said they never made them like that. I asked around the forums and came to the conclusion posted here.
I also note the "B/B" normally cast into the back of SLP runners can't be seen on the set shown here.
I called in fall 2007. At that time, the tech line was answered by a co-owner of the company. He said SLP never made them w/o dividers.
But hey...You never know. He may have been throwing a few back that day!
FYI...The subject cam up like this. I called and asked why dividers where so small (e.g., 1.5"). Their reply was hours and hours of testing provide that to be the optimal config. A few days later I saw two sets w/o dividers in two tubes. Because they were the same, I assumed they were cast that way. (Also, I've seen more sets since then.)
I called back and asked about the tech/thinking with their original design that didn't have dividers in two legs. He said they never made them like that. I asked around the forums and came to the conclusion posted here.
I also note the "B/B" normally cast into the back of SLP runners can't be seen on the set shown here.
Last edited by GREGGPENN; Jul 2, 2009 at 12:19 PM.
Thread Starter
Le Mans Master
Joined: Oct 2008
Posts: 9,758
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From: Houston Texas
I honestly don't care what they are. I'm more concerned with how they will flow. But if we can figure out where they came from that would be nice too.
Pro
Joined: Feb 2005
Posts: 658
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From: Centerville OH
I bought these runners used so I have no history on them. The center runners were not siamesed. The other two were, you can tell they were cast that way. I have been told they are not SLP runners. They are Knock-offs*shrug*.What do you know about them? How will they flow? I siamesed the top as far as I could, 5" or so. I am going to see where my rpms fall off and maybe fully siamese them if needed.
The set you have has definitely been ported and cleaned up. The quality on the first gen runners was HORRIBLE right out of the box. I had to do a bunch of clean-up and have the flanges milled just to get them to fit.
Thread Starter
Le Mans Master
Joined: Oct 2008
Posts: 9,758
Likes: 49
From: Houston Texas
SLP did make runners in that configuration. I still have a set that I bought directly from SLP in 1996, and they are the same configuration as yours
The set you have has definitely been ported and cleaned up. The quality on the first gen runners was HORRIBLE right out of the box. I had to do a bunch of clean-up and have the flanges milled just to get them to fit.
The set you have has definitely been ported and cleaned up. The quality on the first gen runners was HORRIBLE right out of the box. I had to do a bunch of clean-up and have the flanges milled just to get them to fit.
Sorry, for all the questions
Last edited by ch@0s; Jul 2, 2009 at 01:02 PM.
Race Director
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From: Overland Park Kansas
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You never mentioned that to me. So you're saying the ASMs were .2 tenths faster than these? (Maybe that's why SLP said we never made those ) I thought your set went to another member. If you still have them, I suspect ekess would be interested in buying them from you.
gp
Racer
Joined: Oct 2007
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Those are definitely SLP runners. They are of the first design as I bought a set exactly like those around 1991 from SLP. IMHO they are the best ones SLP produced. Maybe the best TPI runners made.
They have very little restriction in them compared to the SLP 2nd design. With the 2nd design they have bolt lug bosses protruding into the air flow and that cuts down on the cross sectional area. Plus they did away with the siamese on the one runner set.
I have modified mine since then by siamesing the other side and I'm making over 370rwhp with a 355. With my new build I expect to break the 400rwhp barrier but with an increase to 369 cubic inches.
Yes those are very good runners.
They have very little restriction in them compared to the SLP 2nd design. With the 2nd design they have bolt lug bosses protruding into the air flow and that cuts down on the cross sectional area. Plus they did away with the siamese on the one runner set.
I have modified mine since then by siamesing the other side and I'm making over 370rwhp with a 355. With my new build I expect to break the 400rwhp barrier but with an increase to 369 cubic inches.
Yes those are very good runners.