edelbrock sp2p or performer 400
 

ive got a sp2p on my 400 now and was cleanin the garage and found another intake i had for the same truck was wonderin which will be best ,,,,,i live at 9000 feet and run a holley650 now and i just swapped in a t18,with 410 gears ,,i really just use the truck for haulin firewood and trash but am plannin to go thru the engine real soon and start drivin it more often

Use the Performer 400, that sp2p was a poor excuse for a manifold.

Why is that?

Read some of the old posts here. If I remember right the runners were too small and it did not perform well. It is an old failed design that did not work well and was discontinued. There are still a few out there being passed around on eBay etc waiting for a sucker to buy them. There are much better alternatives from Edelbrock or Weiand. The manifold has been discussed a "few" times:)

Thanks..I'll do a little searching.

Interesting stuff...LOL. I've been sandbaggin, I have to admit. Love all the misconceptions that get passed around until they become facts. Our 'extreme torque' 408s that we build use the SP2P-400 4V intake with TBI ...on the dyno (we have our own) with the SP2P we get about 32 ft-lbs better than the Performer 400 at 3000 RPM...but more than a 60 ft-lb improvement at 2000.

To be fair, we are talking about specialized trail-rig-only motors that are designed to peak at 3000 RPM, so I won't disagree that the SP2P is not what you want for a highway cruiser or even a general-purpose street/trail package (my own 'GP' '78 Bronco has a Performer 400..). It's just interesting to me to see how things get written off in a blanket, wholesale way.

The user that posted above is looking for a GP vehicle application. Not what a SP2P is good for so the answer is correct for his application which is what we were discussing. The manifold is "peaky" and not very good for a daily driver or most applications but there are always a few applications where anything can work well. It makes a gasser "diesel like" with a very narrow power range. A large number of gears or a gear splitter would be useful with them. If you need more of those manifolds it seems like there is always one available on ebay. Please use the SUPPORT option under the MISC tab in the silver menu bar to become an authorized advertiser/commercial user on FTE. Please check the user guidelines for more information.

??..I do buy them on EBay..that's where you find them. Thanks for all the other great advice..I'll add that the the twenty-five years I've been doing this. And who was advertising anything? Certainly not me..my shop is full, thank you for your concern. Plus..the SP2P is more misunderstood than it is deficient..especially for the road applications they were designed for.

Tim..is this typical?

I had a chance to dyno the SP2P during the 400 project. But time and paying customers got things moved along. I have not read any post on the manifold. I remember when the manifold came out. A customer at the time was rebuilding a 396 in pickup, I can't remember if I suggested it at the time or he picked it up, but he was amazed that he got better gas milage. I honestly don't remember what his coments were about the torque.

During that time I would take my bosses pick-up for deliveries, 350 Chevy with a tach and an automatic. I noticed the usable rpm band and during normal in town driving the tach would barely read 2000 - 2500.

Since then I always wanted to build a 460 with a SP2P, 390 bdl and small tube headers. I figured it should idle about 300 :) and respond like crazy, up to 2500. Probably couldn't make 3500, but I figured typical street drving (and this was about early 80's) the gas milage would be nice. I kind of liked the "pea shooter" technology.

Since it never got build, I may never know. It's possible not being able to wind it up would get old.

'Respond like crazy'..yes, that is good description of what the SP2P does for an engine. 'Dying' at much over 3500 is accurate too. Interestingly..the port section area of the SP2P-400 is very similar to a 351W stock intake..so those that want RPM from Windsor confgurations pay big money for heads that come as close as possible to the Clevelands..and those of us in search of huge bottom-end grunt (and cruise fuel economy..) 'revert' back to the low-volume intake design.

We achieved 496 ft-lbs A 3000 RPM with a 400 and an SP2P with a Holley TBI...and it cracked the 400 ft-lb barrier at less than 2000 RPM. Those kind of numbers realy play well on the rocks, or in mud, with big tires. I'm looking forward to what we'll manage with one of Tim's stroker kits in a current project. I know 500 ft-lbs @ 3000 RPM will be history...8-)

man...that gets a guy to thinking....high compression, propane, oz (lower flow) heads, bet my duration is a bit much though. hmmmm. I'd have to get an overdrive of some kind for sure for 2wd use. But I could do that.

Tim......you are aware of my build...what do you think? wish i'd had the chance to think this over before I got the cam etc. I like low end...a lot!

The engine I noted the numbers for above has the iron Oz 2V heads and was massaged to give us a static CR of 10.2:1. Some minor work was done to clean up the heads and we used Ferrea stainless valves (which are slightly larger than stock valve heads..very slightly) with 4-angles seats, blended. Sorry, no flow numbers..we don't have a flow bench.

Off-idle pedal responsiveness is down-right silly..but the engine sits in a rock-crawler and the beast has a hand throttle..the skinny pedal is too dangerous for its potential to snap stuff if you bump it. But it also goes 'flat' at just under 4000 RPM almost like you hit a rev-limiter or something. As has been noted in this thread ..this particular engine would not be suitable for a 'street driver' without an awful lot of gears behind it.

I used to have an sp2p on my 400, but swapped it for a Weiand Action Plus. the sp2p seemed to give me a little better mileage, but the Weiand is definetly more responsive in the midrange

Curious if port matching to intake or plenum runner blending on carb side would be of any benefit in a daily driver with SP2P 400 manifold?

I don't think the benefits would be that great to be honest. The intake tops out very quickly (roughly 4000 rpm from what I've read).

With porting and polishing, there's no way to increase that number to the full range of usable RPM. With my mild 400 build, my usable RPM range is from 1200 to 5200 with the cam I've got.

If I threw on the SP2P intake, I'd be limiting myself significantly in the range of RPMs available.

Just some food for thought.

By the way - this is an 11 year old thread. lol