Which one do you think is better? The SLP ones are almost $200 cheeper. Has anyone used both and see if one gives more than the other.

 

I've used both when I had a 350 in my car. I thought the SLP runners gave up a lot of torque. The TPIS or AS&M runners( same thing) make more power everywhere. They are worth the extra money.

 

the TPIS runners are made by Arizona Speed & Marine...cost 100 less from them than TPIS.

 

Agreed with the above...dont waste your money on SLP's...Ive used them and the did not feel as strong as the stock runners!! Mid range was somewhat improved but that sotp torque feeling off the line was poor.

Also,the SLP's,while partly siamesed,really need ALOT of porting to make them as big as the ASM runners.The SLP's were in fact,smaller in runner opening than my stockers were and verifiable by placing the gaskets on there..Also,the SLP's are poor fitting IMO.Cant use the pvc lines/pipes anymore because the runners are fat on the outside.

Id get large tubes and a ported base or at least a larger manifold if you MUST have the mods.The stock TPI manifold is a restriction.Expect to see maybe 15HP or so if you get large tube runners and a larger manifold.Thats what 700-900 bucks for a few extra ponies???
Not worth it on a stock engine unless you drag race alot and wan every extra tenth.

:cheers:

 

Bill86 Can I ask you what mods have you performed to your car.

 

From the way you guys talk, I'm assuming you had the early SLP runners. Their 2nd design was far better. Mine have a 1.75" inside diameter, which is substantially larger than the 1.48" diameter of the stock pieces, and just as big as the diameter of my TPIS large tubes. Between the two, I prefer the SLPs. The semi-siamesed design helps effectively shorten runner length, which helps with the high rpm brick wall that we all encounter with TPI. Runner diameter isn't the only thing causing that brick wall... length is. Just widening the runner isn't going to eliminate high rpm breathing issues. By using the SLP runners, and properly porting your plenum, you can move your power band up a little bit. But, just slapping the SLP runners on as-is isn't going to give you any gain whatsoever. The SLPs are for a gearhead that doesn't mind doing a little work. It is essential that you port the plenum to match the runners, and it's also necessary to gasket-match the runners. I found that they didn't line up to the gaskets terribly well.

Also keep in mind that neither brand is going to do much at all if you run a stock base. The runners & base should be upgraded together, and all components (especially the plenum) should be ported to match the gaskets.

If you're not the type of person that's willing to get your hands dirty with a dremmel, I still suggest the SLPs. If you're not willing or able to do the port matching, neither style is going to give any amount of noticable gains, so you might as well waste $250 on the SLPs instead of $400 on the TPIS. Then you'll have $150 to waste on a new throttle body. :lol:

 

Aftermarket Runners on a stock base will give you 0 HP.

Vic

 

So what do you guys think a Port matched plenum, oversize runners and a Accel base will produce on a stock bottom end ?

:cheers:

 

I don't have any actual numbers but thats not what really counts in my opinion...when I added accel runners and intake base there was a very noticable improvement from 1500 rpm on up.

 

I believe the SLPs are rough cast aren't they? Youd need to get them Extrude Honed to be comparible to the AZ speed runners.