MurcoRS

The March 2007 Super Chevy magazine has an article featuring a build-up of a TPI 383 stroker that put-out 458 hp & 534 ft lbs that would wind to 6,500 rpm while making power! I was very interested as I have a tired L98 laying around and was always under the impression that even a modified TPI would be done making power over 5K rpm. The article engine featured TPIS big-tube runners and throttle-body, extrude-honed base, plenum, L98 heads, and a 383 short-block (obviously) with a fairly mild Comp Cams XR264HR cam to make this power. This sounded like a fairly "budget-friendly" build until I found out how much extrude honing ran (wow)! I am still interested in doing a "big-tube" TPI build-up but am wondering if a set of "fast burn" heads with an SDPC vortec TPI base would flow as well or better than the "honed" L98 parts would. Has anyone here put a combination like this together?

Boosted_SS

i have a 383 tpi. one bas azz motor!!! i have the GM Hot Cam, eagle crank, eagle connecting rods, speed pro flat top pistons, 1.6 roller rockers, world sportsman II 72cc heads, and ofcourse the tpi. man does this thing MOVE!!

Brisk

iTrader: (25)

I'm building a motor as we speak, I'm going to have to go and pick up that issue.

EDIT: out of curiosity, how much does extrude honing cost?

LT1FUN

Thanks for the heads-up, I'm definitely going to have to pick up the magazine tomorrow. I checked out Super Chevy's website but unfortunately there' no info about the motor or the mods besides a caption that says:

"Stealth Mode TPI: Building a 458-hp L98 street sleeper."

Where did you hear about the motor spinning to 6500rpm? The highest I've seen a TPI motor make HP was 5600rpm and that was with a set of siamesed AS&M runners and a TPIS base (heavily ported). I have a very hard time believing any TPI motor can still be making power at 6500. On the other hand, if it's true, that would definitely change a lot of people's views on what a TPI intake is capable of....

Somebody should pick up the issue and post some scans for everyone to see. Regardless of what RPM the motor peaks at, 458hp and 534# of torque are AWESOME numbers, regardless of intake style. I wonder what their definition of "budget sleeper" is to get those kind of numbers out of a TPI...


Check out their website here: http://www.gethoned.com/parts.php?ge...how=automotive

They do great work, there's no denying it, but the price's they charge are absolutely ridiculous. Considering there's virtually no "hand-work" being done, (time and labour)I don't understand how the process of extrude honing could cost so much. It's just a machine stuffing an an abrasive substance through the ports on ... whatever it is that you send them. There's no real "work" involved at all....none that's being done by human hands anyways, so why so expensive? It's pretty much all automated. Press a button and sit back and relax....

Here are their asking price's for extrude honing the following TPI parts with their "Level II" process:

TPI upper (plenum) $255
TPI lower (base) $475
TPI runners $325

or get the three together for $810.

All that plus the cost of shipping to and from their facility.

Considering you can buy a brand new Edelbrock intake base for $375 ($100 less) which I'm quite sure will outflow any modified stock base). Pick up some SLP runners for $275 (which will flow way more than the factors runners ever would even extrude honed for $50 less and have a place like CorvettePlenums port out your pleunum for about $190 ($60 less) you start to realize that Extrude-Honing's price's are just way too high for what they're offering...

Brisk

iTrader: (25)

TPI doesn't stop making power after 5000rpm, its just the hp curve flattens out.

I've already got a TPIS base and SLP runners, all heavily ported along with a plenum. I was considering on getting the base and runners extrude honed, but forget that ****!

I've got a 355 engine here that I'm either going to fix up and use, or stoke out. Perhaps I'll use the magazine as a blueprint to make power. Oh yea.. then I'll have to change my tranny and rear end... it never ends!

MurcoRS

Upper plenum - $175
Lower plenum - $395
Heads (pair) - $975
I know it's a fantastic service but when you add in head rebuilds, the runners, and throttle body you're into this build for $2,500 before even starting the bottom end rebuild/stroke.
At no point did they say it was a budget build, I just assumed it would be reasonable seeing as I had many of the parts already.


The dyno charts that are in the article show it hitting 450+ hp from 5K to 6.5K rpm and making over 400 ft lbs of torque from 2.5K to 5.5K rpm peaking at 4K rpm. Pretty amazing!!

MurcoRS

It sure got my attention!!!

LT1FUN

So you have the magazine already?

What are the spec's on the motor? What heads are they running? Cam? Compression?

I'm very curious as to what parts they're running to get those numbers. Very impressive. Especially the Torque.

Brisk

iTrader: (25)

yes I am very curious what combination they're running too..

MurcoRS

Yeah, I picked it up yesterday and haven't put it down yet!
The block had a Coast Performance 383 stroker kit that made 10.6:1 compression with the ported (extrude honed and a "competition valve job") L98 heads, "Honed" factory upper and lower plenums, TPIS "big-tube" runners and throttle-body, FAST 36 PPH injectors, and a Comp Cams XR264HR cam (.487/.495 lift, 212/218 duration, 110 deg lobe separation) with 1.5 roller rockers. The dyno run was made with a FAST XFI contoller, Hooker 1 5/8" long tube headers with 3" magnaflow headers, and no accessories.

LT1FUN

They made 458hp a 534# of torque with the factory heads and base?? Running only 1 5/8 headers? I'm definitely going to have to pick up that issue tomorrow. Those numbers just seem too good to be true considering the parts being used....

You wouldn't happen to have a scanner do you? It'd be great if someone could host some scans of the article...

Brisk

iTrader: (25)

I have a scanner and I could host some pics.. but I won't have the magazine until tomorrow.

Orr89RocZ

iTrader: (20)

repost.... another thread talks bout this but i'm scanning the articles now

Brisk

iTrader: (25)

link to the other thread?

Orr89RocZ

iTrader: (20)

https://www.thirdgen.org/forums/tpi/...t-stroker.html

Orr89RocZ

iTrader: (20)

for some reason when i use IMG commands the full size pic doesnt come up so its hard to read if not impossible

but here the links for pages 1-7 of the article...click the link then click the bottom right corner of the pic (an icon will pop up when u hold the mouse over it) for full size


http://img176.imageshack.us/img176/8557/scan0001qx0.jpg
http://img246.imageshack.us/img246/2331/scan0002lx4.jpg
http://img295.imageshack.us/img295/4224/scan0003tt3.jpg
http://img260.imageshack.us/img260/8319/scan0004qg7.jpg
http://img245.imageshack.us/img245/8063/scan0005hz4.jpg
http://img259.imageshack.us/img259/7056/scan0006vk1.jpg
http://img201.imageshack.us/img201/4016/scan0007cn1.jpg

LT1FUN

You're a good man Orr89RocZ.

Orr89RocZ

iTrader: (20)

hey no problem...enjoy the article! just goes to show you what no accessories and aftermarket ECM tuning does for a motor....cuz thats a SMALL cam in that 383 and its making big big numbers

Brisk

iTrader: (25)

yea those look like gross hp numbers.. with no accessories, etc. big difference in the 'real world' when its actually in a vehicle.

thanks for the scans!

The Project

iTrader: (6)

Thanks for the article. I have printed it and put it in my vault. Cheers

Damon

Did they dyno the motor at the Westech dyno? If so, that would explain a lot.

There's a lot of guys on this board who have been tinkering with TPIs for a long time. I've messed around with them myself, too. If you think there's a "magic formula" that suddenly changes all the rules of building a TPI engine there's probably a nice patch of swamp land in Florida with your name on it. The phrase "too good to be true" comes quickly to mind. Until that motor gets stuffed under the hood of a 3rd gen Camaro and posts a jaw-dropping 11.99 at a real dragstrip, all-motor, please try to refrain from jumping out of your chair too quickly.

Those kind of power numbers, if true, are what an 8L Viper V10 put out just a few short years ago.

3rdgenZ

iTrader: (1)

even still with those numbers, thats a very capable 11sec motor for a 3rdgen.

Orr89RocZ

iTrader: (20)

if it made 458 on motor with accessories then it might do some good 11 second runs...

but it does without accessories...add acessories and it drops to near 400crank hp or so...maybe alittle less. then drivetrain loss and its around 320-330 whp at most..which is solid 12s but no 11's unlesss serious diet is put on.

3rdgenZ

iTrader: (1)

yea but its the torque thats going to get it done. with a good setup that thing would feel like a rocket ship off the line.

ditchbangr

iTrader: (1)

I know the article is about building a stock appearing motor that put out big #'s. But reading the article I wondered what kind of power it would make with a stealthram, superram, or LT1 converted intake. I too was skeptical about their #'s, carry on...

Orr89RocZ

iTrader: (20)

if you can hook. lol needs a very strong rear end thats for sure! lol

as far as other intakes...i'm sure they would be capable of making a few more hp, but what limits that is the camshaft they use. that cam is small enough for TPI so swaping to other intakes that favor higher rpms wont yeild a big increase in power. it might make 10-15hp up top end, but the bottom end torque will be lost, and even some low rpm hp. so the gains would be canceled out.

that motor with a bigger cam suited for 383's would be interesting to see, even with TPI. i wouldnt run that cam in a TPI 305, let alone a 383. thats a small cam. I'd look into a 224/230 like cam...or even a 230/236 with extruded TPI and good heads. cam like that on that motor with no accessories might be pushing near 500 crank hp.
stealth ram/mini ram 383's with 230/236 cam are proven 450hp motors with accessories... no accessories and aftermarket EFI management, the power numbers would be impressive.

3rdgenZ

iTrader: (1)

i was thinking atleast a 218 224, that is a very small cam. i just bought a crane Z cam for my L98 its 218/230 .456/.489 along with the new runners it should pull nicely above 4000rpms.

Orr89RocZ

iTrader: (20)

yep sounds good man! let us know how it acts on that L98

MurcoRS

How good can the L98 heads flow, even with "extrude honing"? Would they outflow box-stock "fast burns" or the AFR 195's?

IROC-You

Im more suprised that the heads flowed enough to make those numbers!

MurcoRS

The article didn't go into much technical detail so I left a message on the SS board to hopefully get some more info. Here is the message I left;

I hope we get some more info as the moderators are editors from the mag...

Orr89RocZ

iTrader: (20)

those heads flowed 260cfm they say... which is pretty impressive. I'm also inquiring to a cylinder head porting shop on what they think they can get out of the L98 heads.

problem with those heads is valve size... i dont think you can run much larger than a 2.00 and 1.56 valve in those heads. that will be a limiting factor for sure.
But even so, 260cfm and a good exhaust flow, somewhere over 180-190 cfm or more will make some good power with the right cam and intake.

AFR 195's match that out of the box or so they advertise. fastburns should be around 250-260cfm atleast..they have a 210cc raised runner

Cat59

Speaking only for myself. I'm unable to download this link. Maybe this link has went sour?

Cat.

88BlackZ-51

iTrader: (2)

That is not a budget build by anymeans. By the time you extrude hone that intake, and get the work done to the heads you are talking alot of cash.\

I didnt hear the work "budget" in the article, but when I think of a "TPI" intake that word just comes to mind. The thing I do like is that is it "steath" looking.

I wonder what it costs to build that motor?

Orr89RocZ

iTrader: (20)

works for me? should be still up and running. try again and if it dont work, i could email you the last pic




agreed. its not that cheap of a build. the shortblock is a budget street/mild strip use shortblock, but extrude honing base and heads costs a good bit. if you didnt already have aluminum L98 heads, you'd be better off just buying a aftermarket set like DART or TrickFlow. I think the cost of the L98 heads setup for big cams and the portwork would rival the cost of a aftermarket out of the box head. And the TPI system aint cheap either...extrude hone base is as much as a aftermarket base. aftermarket big tube runners are over 400. TPI is not a budget setup in my eyes...and you dont get the performance one would like, compared to HSR or others. only HSR is cheaper tho...rest are fairly expensive too

3rdgenZ

iTrader: (1)

i (personal) would only extrude the base. i can port the upper manifold myself. even still 400 bucks for the runners and another for porting the base. its not cheap but still even when it gets in the car your still talking about over 450 lbsft of torque. on the street thats a lot of fun.

MurcoRS

Here is what was posted today;

And later....
Interested in what that "used cam" was??? Me too!

Orr89RocZ

iTrader: (20)

wow watch it turn out to be somewhat large of a cam.... how many readers read that and thought lets get a 264 cam and make 450hp. i dont see it happening. else, i'm takin off all my accessories

Bullydawg

iTrader: (7)

Not to steal this thread, but did you guys see the car craft 6.0l truck motor they got and added a cam,carb, and headers and was putting out 480HP for $3,775? It's on page 38.

3rdgenZ

iTrader: (1)

that build was almost a mirror image of the tpi shoot out in super rod
http://compcams.com/Community/Articl...?ID=1737510521
the SS aticle actualy made more power with the EH base. the cam used in the SS article is almost the same as the cam used in the GMHTP article.

MurcoRS

Could this be a recycled article? Many of the same pictures are used here! The 3rd pairing (factory TPI vs. Extrude honing and big-tube runners) matches SS's engine's power curves almost perfectly, even though this Super Rod engine used an XR288HR cam and TFS heads! Something smells!!

Orr89RocZ

iTrader: (20)

thats all? my buddies 6.0L made 450 at the wheels with a Trex cam... thats over 520 on motor.


yeah thats what i was wondering...they made similar power but Super Rod used a HUGE cam.
the pics dont work in the Shootout thread...atleast for me they dont... i'd love to see that article again

3rdgenZ

iTrader: (1)

WOW i didnt even realize that. they have the same pics, literaly. the numbers thou are different. the power curv looks the same simply because its the same induction system. the heads in the SS article are better suited for a TPI intake than the super rod article's TFs. in the SS article they got the same power with the stock base as the Super rod did with the TPIS base.

look at pic #9 in the SS mag and compare it to pic #15, its all diff. look at the DFI in #15 and the dampener. its the same pic in the super rod mag. same thing goes for the TPIS stuff and the pic#11. i dont think that they copy and pasted it thou, the numbers just are'nt the same.


0rr89RocZ> checkout the first post i made with it. it should work.#40