mrr23

this is from only swapping to the HSR. no prom work, nothing. went way lean in the upper rpms due to more volume of air.

http://stealthram.com/dynoresults.html

zerotosixtyV8

gave up 30 ft. lbs for 10 HP... I dunno if I like that trade off so much, powerband looks about the same. HSR on a stock motor = not so good lol. but it also shows that TPI intake is not the restriction, the heads and cam are what keep it stuck below 5000 rpm. have any charts of it on a build motor?

age

zerotosixty: no offence, but if you read beyond his first sentence, he did say that there was no prom tuning done. To me, prom tuning a car still constitutes it as being a "stock motor", because tuning is tuning. I'll still stick with a properly tuned HSR over a TPI, even if it's just for the practicality and simplicity that the HSR provides.. Sorry if I sound bitter, but I'm just sick of people putting down the HSR/LT1 without thinking about "tuning".

mrr23

people really need to stop looking at peak numbers. look at the whole curve. i run my motor in the 3000-5500 range. well so do most others. at 3200 the HSR takes over. i gained almost a tenth NA and 3 tenths on 150 n2o. and this gain was over a fully siamesed SLP runners and Edelbrock base.

click the green banner and then go to HSR CARS. look at what other people have built and there are dyno graphs there also.

zerotosixtyV8

no one is putting it down, it's a great intake. of course you need tuning, but on a stock 350 it' doesn't give the results it would on a matched engine combination. stock L98 is a low RPM motor and doesn't flow well, a tunnel ram is for a higher RPM motor as that A/F graph showed. prom tuning is still not going to stop the HSR from outbreathing the rest of the motor.

age

obviously, if given a choice, I'd much rather do a head/cam swap over an intake swap. But this isn't about a head/cam swap, and I'm sure that with an HSR, you're allowed more "options" as to what cam you wanna run.

I guess the part where we differ on opinions is the point where mrr23 noted that the HSR hadn't been prom tuned (therefore more is still to be had). Like mrr23, I also like to run my car from roughly 3500-5500rpm, so the torque/hp curve will suit me better (be it in stock form or not) especially AFTER prom tuning.

Guest

Way lean... now there's an understatement.

I agree about not looking at the peaks, especially in places where it doesnt matter. Looks like a good trade to me, once you get that AFR dialed in it should make a huge difference.

zerotosixtyV8

both cars weren't tuned, so certainly there can be some gains from an SLP TPI as well as an HSR. I think for someone running closer to stock components a TPI will work better for them that's all. For any kind of 400+HP beast, an HSR is almost a necessity.

Ray87Z

Actually I'd say it's fairly impressive that the HSR outperformed a upgraded TPI system, but still with the stock heads/cam. You still have more lowend torque than you can use effectively with street tires so it seems to not be much of a tradeoff to me. You picked up around 10hp basically at everything over 3700rpm. Plus the potential is now there to really come alive with at least a cam swap. Over a regular stock TPI the hp gain would have been even more impressive, don't forget that this comparo was against a fairly expensive upgraded TPI system not a stocker... Those upgrades likely cost more than the HSR did so if you're still stock TPI wise the HSR looks like the clear winner to me...

zerotosixtyV8

that's true, those bloody runners cost as much as an HSR. too expensive for that junk IMO lol. but still doesn't a fully ported SLP system with big mouth base only flow like 210 cfm vs. a 190 or so for a bone stock TPI??

gixxer9

HSR is an absolutely night and day difference from the LTR setup for me! The guys are right about the rest of the motor needing to be setup. My car became an animal with the HSR. I had all my motor components with the LTR plus a high-flo base, and it was a dog. I swapped my stealthram in and ran an immediate 12.4 before breaking one of my hydraulic rollers in half! With the HSR, my car wants to rev to 7000 rpm, and therein lies my lifter troubles... I'm installing a solid roller and 7/16" valvetrain components as we speak. Stealth ram is definitely designed to rev, so you'll need matching components to complement that (heads, cam, exhaust, valvtrain). I'm fully expecting to break the 11's in the spring. I probably could have gotten closer this year, but I broke my lifter during the run I made.

Guest

Take another look at the AFR and tell me that tuning the previous setup would make anywhere near the same difference as tuning the HSR setup he has.

zerotosixtyV8

with what you have to work with yes. on a better breathing motor, the HSR would go charging away from the SLP setup like no tomorrow. tuning won't stop the HSR from outbreathing the rest of the motor. why are you getting all pissy??? I said on a stock L98 an HSR doesn't do that much!!! mr223 said himself he only dropped a tenth on the motor!! I never once said an HSR was bad.

age

he said that the tenth gain was over an already upgraded TPI setup which I'm sure mrr23 had spent some time prom tuning..

Guest

Pissy? lol

You were the one who said "both cars weren't tuned, so certainly there can be some gains from an SLP TPI as well as an HSR."

And I am saying that just looking at his AFR on the dyno sheet its obvious that on his car, the gains of tuning the SLP setup would be minimal at best, while those of the HSR would be quite significant. It would make the gap between the two much larger. I'd even bet you that with some timing adjustments at the lower RPM's, you could wipe away most if not all of that loss.

I guess everyone has their own boat. Those who want to pull trailers, and those who want to race.

mrr23

you'll notice i stated this was run on a stock 1987 .bin. the only tuning i did with the SLP/Edelbrock was to the MAF table 1 to get it to idle better and change injector constant to 24# still the a/f was 11.8:1 but madmax is right. there would've been minimal gain leaning it out more. i may have gained about 4-5 hp leaning it up some. also side note here. i cut the divider completely out of the SLP runners. all the way to the base. left the divider in the runner where it mounts to the base.

now the HSR used the same 1987 .bin. with it's 15:1 a/f, there is much gain to be had there. also a side note here. this motor has 2 cylinders at 80 psi due to broke rings again. smokes a little.

if you click the blue banner and go to dyno sheets you'll find a comparison from the stock runners and completely siamesed stock base and LT1 cam vs. the SLP/Edelbrock and ZZ4 cam.

tell you what. i'll see if i can get on the same dyno i did the others on before i pull this motor. that way i can get some graphs comparing the stock setup also.

as far as the timing is concerned. i use the holley prostrip annihilator igninton system. i have bypassed the ECM and control the timing curve through it. i have 36* in by 2500 rpm.

zerotosixtyV8

I said the same damned thing. on a modified motor the HSR will pull away while the TPI will be sitting around acting like junk. on a stock motor, there is nothing you can do as far as tuning is concerned to keep the HSR from out flowing the intake, short of choking it off as well! tuning on a stock motor with even a modified TPI can yield decent gains! you make it sound like I am saying the HSR is a poor intake.

mrr23

well i dyno'ed today. unfortunately the 2 bad cylinders are starting to catch up with me. the dyno shows the loss under 2500 rpm. but now in the upper rpms it shows the same hp and tq lines. so it's a tainted graph. but, i'll put them up later to show what's happening.

zerotosixtyV8

mrr23 do you have any comparisons between the HSR and a miniram or LT1 intake on similarly modified motors?

mrr23

we have a member, mike davis, that has done that.

http://stealthram.com/intakecompare.html

and here's his site with the dynos

http://www.eecis.udel.edu/~davis/z28/winter01/dyno/

side note. for giggles i bought myself a new compression tester and decided to do another compression test. well the #3 that had 80 psi last time now has 140 psi. pretty much i will have to assume i did something wrong the last time. but i'm still losing oil and smioking. so that leaves another cylinder somewhere bad.

Kevin Gray

If your valve seals are leaking and oil drained into the cylinder,, and you did a "cold" compression test, that could be the reason your reading increased from 80 to 140,,, and there could still be a problem there. Another reason could be the rings were,, or are seizing, meaning they're not rotating on the piston freely. This will also give you a high then low reading from one test to the next. Then there's always the chance that you had the preload on the lifters tight (valves not closing),,, if you readjusted the lifters later correctly,, that would give your compression back. So,,, it's hard to say if you did anything wrong or not when you tested 80 pounds.

mrr23

more than likely it was the other gauge i used. probably didn't have it tight enough. the valve seals are posi seals not even 5k old. didn't readjust the lifters. the 80 psi was cold, the 140 was warm. the last time i broke the #8 top ring, i was at 135. the rest were at 175. i'm still positive it's another broke ring. just cylinders not as bad off as i thought.

mrr23

also remember this is from an untuned HSR swap.

mrr23

ok here's the graph comparing my stock runners, siamesed stock base ( by siamesed i mean all the way to the head side) and LT1 cam vs the HSR and ZZ4 cam.

http://fl-thirdgen.org/mrr23/images/...t/dyno1419.jpg