Hello

Sorry if this common stlye of question angers anyone but i needed comfirmation about the info i got from searching.

Slp runners work very well when port matched to the plenum, however cannot be ported or siamesed very much.

Edelbrock runners work reasonably well out of the box but have more porting/siamesing potential than the slp runners do.

Now please correct me if I am wrong on any of these accounts, I want to get the better of the two and any suggestions are greatly apreciated.

Speed

 

I know most people would just shove the search in my face, but i did search and i didnt get my answer.

All i want to know is which of the two is better and which of the two is more port/siamese friendly.

Speed

 

IMHO the Edelbrock runners are better out of the box. However it is the SLP runners that can be opened up or modified to your hearts content. You can work with the Edelbrock runners but it would take more work to do so.

So out of the box or slight modification go with the Edelbrocks. For a little more work SLP's are the way to go and for bigger power. The SLP's are the route I took.

 

can edelbrock runners be ported and siamesed?

Speed

 

Edelbrocks do flow better "out-of-the-box" than the SLP's, that much I'm sure of after reading numerous TPI comparisons over the years. But I'm pretty sure the SLP's have a bit more potential because you can port the hell out of them, more so than with the Edelbrocks.

Between the two, if your looking for a TPI runners that are more likely to be able to support future mods on your motor, I'd go with the SLP's.

Having said that, have you ever considered Arizona Speed & Marine's "Big Tube Runners"? They have the stock design (which is the coolest looking set-up in my opinion ) and out-flow every other TPI runner on the market. 260cfm/runner right out of the box Blows away every other runner on the market.

I'll be ordering a set in the upcoming weeks myself for my L98.

They're just a possible option you might want to consider before you buy anything.

They're about $415
1985-1992 Large Tube Intake Runners

which, is a bit more than eith the SLP's or the Edelbrock, but with their factory appearance and much better performance, you might want to consider saving up a bit more and getting these instead.

Have you seen this article entitled "10 Times The Torque"

It's a really good read.

Articles That Use Comp Cams® Products

 

You can;t touch the ASM runners. So i woud toss them out. Edelbrocks can be ported and siamesed just as much as SLP's . Mine are ported and siamesed in 4 "deep . So if you don't mind spending the extra cash go Edelbrock. Check my www. for pics of them on the car . You can see the port work .

 

Why would you want to when they out-flow every other runner on the market by a sizable margine?

Neither a ported set of Edelbrocks or SLP's will flow like the AS&M's (or TPIS runners for that matter)

If you send off the SLP's or Edelbrocks to get ported professionally, you'll end up paying more over all, then if you'd just bought the AS&M/TPIS to begin with and like I said, they still won't flow as good.

Despite what the nay-sayers would have you believe, not all TPI runners are equal. There's a reason why AS&M/TPIS runners are the most expensive runners on the market - they outflow every other set of runners available. Just remember, if you want the best, be prepared to pay for it.

Food for thought....

Now, don't get me wrong, I'm not putting down the SLP's or Edelbrocks, they're both far better than the factory runners and have more potential than the fatory runners, but if you want the ultimate TPI set up, a pair of AS&M big tube runners and TPIS big mouth base are the cream of the crop. The best of the best. That's why both pieces are so much more expensive than everything else.

It's not that other brand runners are bad, they're just not quite as good as the best. That's all I'm saying.

 

Honestly, the margin of power gained between the two is so marginal that I would go with the SLP runners for looks alone. I pure hate the way that the Edelbrocks look.

 

Don't forget Extrude Hone either. I believe that smoothness is the key to flow. I got my Edelbrock runners done for under $200. This included opening them a little to gasket match them.

 

umm there is guy on here that has completely siamesed a set of SLPs ... I doubt the ASM even touch them . Pretty sure he has the highest flowing TPI on here ( SLP ported all to heck)You ever see a set of ASM runners get over 5000 rpms yet ? I haven;t But when you take the SLP and Edelbrocks and treat them to a solid port job .... I can't see how the ASM compare really. Are the a bigger inside diameter port than the Edlebrocks ( which are bigger than SLP)


I can;t stand the look of them crappy SLP's . But the ASM do look pretty darn sweet.

Anyone got some good dynosheets of how high a motor can rev with each ? Like Mine is only running 4900 tops now , because of my weak stock port heads.

 

Here is a dyno run with hogged-out SLP runners and Edelbrock manifold:

http://users.erols.com/gcwestph/dynorun17.jpg

The hp peak is at 5300 rpm, but it carries out to 6300 rpm before really dropping off. The engine specs and everything else are at:

IROC

 

great link man ! Wonder what heads were on that . Mine only peaks at 4900 , because of the stock port heads I am guessing. Now we gotta see some ASM comparo's . I don't think they go over 5000 rpm . Or if so , it's not as nice a curve as that one for sure.

 

Thanks. They're Trick Flow 23-degree heads. I had the combustion chambers opened up to 70cc to drop the compression ratio down to 10.5, as well as a 5-angle valve job, but the ports are untouched. Here's a link to a bunch of dyno runs I've made with stock runners/Edelbrock manifold, mildly ported SLP runners, and then after the head work and hogging out the runners and manifold.

Dyno Runs

 

How many cfm do stock runners flow? Any idea. What about the edelbrock n slp ones?

Can runners actually be fully ported? Sure you can port away the ends, but can you get right in the middle of the runner to port that? If not, isnt that still the most restrictive part, therefore the rest of the porting will have minimual effects?

 

Greg, very interesting dyno graphs. I like how you made 290 horsepower from 5000 rpm to 6000 rpm and with TPI no less. I bet a lot of people are over looking that fact. I'm trying to extend mine like yours to the 6000rpm range. I shall find out with my next round of mods.

 

I am impressed aswell . I am curious how ported them runners are ??? Just refering to a guy on here named Kevin something or other. He hogged out a set of them SLP's about as far as possible ( absolutely NO divider in the middle). But I think he gota tops of only 5300 ( which I thought was still DAM good )

 

In this picture:

http://users.erols.com/gcwestph/runner1-sm.jpg

You can barely see the start of the dividers. I know I ported the bottom runner openings and the manifold out to 45 mm, and I think the top runner openings are about the same size. I couldn't fit my Dremel tool in much further, but I'm sure they can be ported out further with different tools. Even though I couldn't get down to the middle, I still picked up a lot of power on the top end, particularly above the horsepower peak.

 

Did you ever. I am thinking that the 45 mm base port is what realyl woke it up there.

Frigging way to go man , I have your home page saved , watching for updates

 

Hi Guys

Kevin91Z, Dyno Don and myself all have the hogged out and highly modified SLP runners along with the opened up Edelbrock manifold. All of us make between 324 and 330 horsepower at the rear wheels.

What we do not do is extend the power to the 6000 rpm range like Greg does. Our power falls off quicker than Gregs does and peaks around the 5000 to 5100 rpm range. This is also shorter than Gregs peak power which looks to me like around the 5300rpm range. Like I said above I'm very impressed with Greg's dyno graph expecially considering it is TPI.

We are all modifying our cars this summer but still keeping the TPI. We will be tweaking the TPI also. So this fall when we get back on the dyno and to the track we will post our results. TPI lives on. Good going Greg.

 

yes you guys were to whome I was refering . How big did you open up the manifold ? Like greg says he went from a 42 mm ( stock casted Edlebrock) to 45mm. I am just trying to figure out where he got that topend from . As your runners have absolutely NO divider in the middle ( opened up more than Greg's) . Maybe the secret is in the base.....

 

Thanks. As much as I like my TPI setup, I installed an HSR last month, just need to tune up the Power Enrichment and timing before hitting the dyno and the track again. My goal is to get into the 11's this fall and I knew that wasn't going to happen without changing a bunch of other parts (converter, long-tube headers, etc) if I kept the TPI. I ran 12.47 at 110 mph last year, with a little tire spin and axle hop off the line. New adjustable shocks and airbags should cure the hookin' part, and an extra 30-40 hp should get me there.

 

I agree that the Holley SR is the way to go. But unfortunately here in California to stay smog legal we only have two choices. TPI or the Accel Super Ram. So we will continue to mod the TPI system as that is more fun.

If I remember correctly my intake was around 1.73 inches at the opening. I have had it Extrude Honed. I'm going to open it up a little more this time around plus a few more tweaks. Maybe to 1.75 inches. Also thinking about some thermal heat barriers to keep the intake air cooler. Will be trying out some new ideas.

By the way Greg those are great times for a TPI system.

 

I must respectfully disagree...
370-380 RWHP is more fun. (SuperRam)

 

Yep, Cali92RS and Vincent Z28 have some very respectable Accel Superram cars. Both are in the 370RWHP range with their 355's. I suspect that number will be going up. Make's us TPI guys have to work even harder to keep up. Hey Ken, see you at the dyno and the track. I'm up to a good challenge.

 

I am adding a turbo to make me keep up