Boost Build Up/Higher RPM

WDRacing · #1 (**permalink**) 01-02-2006, 01:23 PM

You guys will have to bare in mind I'm a DOHC inline guy. All of my experience is from Skylines over in Japan. But the prices of JDM parts and total lack of torque don't suit american soil or my wallet anymore.

I'm, buying a 3rd Gen Camaro (Iroc if I can find one) and will be building/installing a large single turbo system. I know everything I need to about timing and fuel tuning mixed with methonal. What I am fairly clueless on is basic V8 building. Other then balancing and a complete forged rotating assembly, I'm at a loss. Hopefully this is where you guys come in. I'm looking to be on a budget...but not a tight one, meaning I'd go with GMHP instead of AFR if the difference in output is negligeable. Ok enough background...

I want a small block, not partial to stroke or bore, with a 7200rpm rev limit. Boost won't be a factor till past 3500 or so, but I'm a big fan of N20 for launching. Engine management will be from a F.A.S.T standalone or SDS haven't decided yet.

Cam dur/lift/overlap on a V8 confuses me. Hyd or solid???

If there is a thread or sticky or book that I can read that will answer most of my questions about this type of buildup I'll gladly read it.

I really just want to start getting a shopping list together so I can have a few goals set. And brush up on all the V8 building jargon I'm otherwise ignorant about.

Appreciate anything you guys can do.

Anyone else on here with a high boost 3rd Gen?

White Phoenix · #2 (**permalink**) 01-03-2006, 05:07 AM

for a high boost 3rd gen the revs high? call me crazy but we are running a tricked 305 motor in my uncles SCCA car. We easily put down 450 on a mild track setup with stock bore and stroke. We use the 305 because we are allowed more modifications but also due to the smaller stroke it allowes us higher rev limits... we are running currently a 8.5k rpm redline...

but thats just what we did for a high rpm motor... now boost changes things alot... 350 and 383(stroked) parts are going to be way cheaper so id go that route... id say stick with a 350 with a nice forged rotating assembly and some good heads. Obviously stick with a lower compression around 8.5:1. Maybe put in a T76 if your feeling good.

Here is a link to my buddies LS1 with a single T76 putting down like 560 on 6lbs... hes looking for close to 1000 rwhp out of this setup
http://www.public.asu.edu/~nicolasd/

WishIHadACamaro · #3 (**permalink**) 01-03-2006, 01:31 PM

^ cool.

WDRacing · #4 (**permalink**) 01-03-2006, 06:40 PM

I have a TO4R I'll be using, good for 750WHP or so in the trim I have. Plus it'll boost just after 3 grand now that I look at the maps again. My plot originally was a 3.0...duh. Few more cubes to count on, so the RPM doesn't have to go as high as I wanted. Although I'm fairly addicted to seeing 8 grand shifts...My Skyline was shifted at 8200 and my Celica at 8300, course my Celica doesn't have any torque until 7000, but she's just a daily driver for gas mileage reasons.

In the end, I'll be looking for 850-1000 on the bottle. Bottle being a track only option of course.

On a side note, I may have a deal on a 98 Camaro SS. The LS1 I already love and have seen incredible things on the stock block alone. That may be the route I end up going.

Thanks for the link, those are GREAT numbers for 6 psi. I was running 28-31 PSI to get those numbers out of my Skyline, not to mention enough alcohol to kill an entire herd of cows.

WD

JunkyardTurbos · #5 (**permalink**) 04-17-2006, 03:44 PM

As far as a cam is concerned, keep the overlap to minimum. Look for about a 115 LDA. You don't want a reversion problem. Run a bit more exhaust duration than intake. Keep the lift down to reasonable numbers if you are revving high. You don't need it anyway with the turbo. Duration in the 220's at .050 will suffice. Look to CompCams for some good boost camshafts.

Rare4thgens · #6 (**permalink**) 04-18-2006, 01:48 AM

Quote:

Originally Posted by White Phoenix

for a high boost 3rd gen the revs high? call me crazy but we are running a tricked 305 motor in my uncles SCCA car. We easily put down 450 on a mild track setup with stock bore and stroke. We use the 305 because we are allowed more modifications but also due to the smaller stroke it allowes us higher rev limits... we are running currently a 8.5k rpm redline...

but thats just what we did for a high rpm motor... now boost changes things alot... 350 and 383(stroked) parts are going to be way cheaper so id go that route... id say stick with a 350 with a nice forged rotating assembly and some good heads. Obviously stick with a lower compression around 8.5:1. Maybe put in a T76 if your feeling good.

Here is a link to my buddies LS1 with a single T76 putting down like 560 on 6lbs... hes looking for close to 1000 rwhp out of this setup
http://www.public.asu.edu/~nicolasd/

WTF heads and valvetrain are you using on a 305 to get it to rev anywhere near that high? Not trying to sound like a dick, but I know these things are notorious for not liking to spin up. Maybe I won't turn the 305 in my 83 into a coffee table...

As for what this guy needs on his list, I am sure you know about 4 bolt vs 2 etc...splayed vs not. Unless you go to an aftermarket block, all years from 1rst gen small block 350-400 are the same in strength. Deffinately go full roller on the valve train. What about chasis set up?

BTW, I used ot live in Tuscon, do all the Rice still crash up and down Speedway?

greasemonkey · #7 (**permalink**) 04-18-2006, 04:19 AM

your parts list and 'budget' term don't seem to coincide, then again budget is just a matter of perspective....5 grand for me is 100 grand for someone else.

I think you'd be way better off going to an LS1/4th gen. I run a 3rd gen camaro drivetrain in my '56 and I'm very familiar with the TPI and the aftermarket upgrades necessary for various power levels. The more I learn about the genIII engines the more impressed I am, plus there are SOOOOO many aftermarket parts available it's really not cheaper to build a genI sbc.
take $10k and throw it at a genI and an LSx, you'll be way ahead in longevity, reliability and power from the genIII, it's just a way better platform to start with.
not saying that you shouldn't but you don't necessarily NEED to use nitrous to launch with a turbo'd v8...don't underestimate the amount of torque you'll have starting at 3 grand. unless you just want to run a rediculously large turbo and need help spooling it up.

about the 305, it's not a bad engine, they get a bad name from the absolutely useless factory cylinder heads. the 305 is basically a small version of a 350 stroked to a 383...put crappy heads on a 383 and it sucks little nuts, too. good heads and the rest makes the 305 pretty dang potent.

Rare4thgens · #8 (**permalink**) 04-18-2006, 08:37 PM

Quote:

Originally Posted by greasemonkey

your parts list and 'budget' term don't seem to coincide, then again budget is just a matter of perspective....5 grand for me is 100 grand for someone else.

I think you'd be way better off going to an LS1/4th gen. I run a 3rd gen camaro drivetrain in my '56 and I'm very familiar with the TPI and the aftermarket upgrades necessary for various power levels. The more I learn about the genIII engines the more impressed I am, plus there are SOOOOO many aftermarket parts available it's really not cheaper to build a genI sbc.
take $10k and throw it at a genI and an LSx, you'll be way ahead in longevity, reliability and power from the genIII, it's just a way better platform to start with.
not saying that you shouldn't but you don't necessarily NEED to use nitrous to launch with a turbo'd v8...don't underestimate the amount of torque you'll have starting at 3 grand. unless you just want to run a rediculously large turbo and need help spooling it up.

about the 305, it's not a bad engine, they get a bad name from the absolutely useless factory cylinder heads. the 305 is basically a small version of a 350 stroked to a 383...put crappy heads on a 383 and it sucks little nuts, too. good heads and the rest makes the 305 pretty dang potent.

You can and I have built a full roller, factory 4 bolt block 500-700na+ hp sbc gen I (not injected ) for just over 5 grand. No way you will do that with an LS based engine even if it was carbed. If injected, the computer and core/long block would set you back at almost 2 3rds that not to mention mounting it and then a computer controlled trans no matter what.

How do you figure a 305 is a 350 stroked to a 383? Did I miss somethin in all this? Do I need a nap?

WishIHadACamaro · #9 (**permalink**) 04-18-2006, 09:08 PM

Quote:

Originally Posted by Rare4thgens

Quote:

Originally Posted by greasemonkey

your parts list and 'budget' term don't seem to coincide, then again budget is just a matter of perspective....5 grand for me is 100 grand for someone else.

I think you'd be way better off going to an LS1/4th gen. I run a 3rd gen camaro drivetrain in my '56 and I'm very familiar with the TPI and the aftermarket upgrades necessary for various power levels. The more I learn about the genIII engines the more impressed I am, plus there are SOOOOO many aftermarket parts available it's really not cheaper to build a genI sbc.
take $10k and throw it at a genI and an LSx, you'll be way ahead in longevity, reliability and power from the genIII, it's just a way better platform to start with.
not saying that you shouldn't but you don't necessarily NEED to use nitrous to launch with a turbo'd v8...don't underestimate the amount of torque you'll have starting at 3 grand. unless you just want to run a rediculously large turbo and need help spooling it up.

about the 305, it's not a bad engine, they get a bad name from the absolutely useless factory cylinder heads. the 305 is basically a small version of a 350 stroked to a 383...put crappy heads on a 383 and it sucks little nuts, too. good heads and the rest makes the 305 pretty dang potent.

You can and I have built a full roller, factory 4 bolt block 500-700na+ hp sbc gen I (not injected ) for just over 5 grand. No way you will do that with an LS based engine even if it was carbed. If injected, the computer and core/long block would set you back at almost 2 3rds that not to mention mounting it and then a computer controlled trans no matter what.

How do you figure a 305 is a 350 stroked to a 383? Did I miss somethin in all this? Do I need a nap?

maybe he meant 327 is a stroked 305?

greasemonkey · #10 (**permalink**) 04-20-2006, 03:55 AM

I said it's a "small version of" a 383. What I meant was that the bore/stroke ratio is almost the same, which makes it the same but smaller. the 305 and 383 are pretty extreme undersquare engines but they offer an easy platform for a nice low rpm torque curve.

Bore/stroke ratios:

305 - 1.07:1
383 - 1.05:1
350 - 1.15:1
377 - 1.18:1

aight, I was a little inaccurate on the price but it really wouldn't be a whole lot of a difference in price between a gen1 and genIII to build a turbo engine, the difference in price would be more than worth the technology you'd gain, mainly in the heads and valvetrain but also the oiling system and the EFI.
either way you've got to build a short block, get aftermarket heads(maybe not with the LSx? definitely for the genI)
I'm not saying you can't make power with a genI, just saying that the genIII is a LOT better platform to start with and the price isn't outrageously different anymore.

I just bought an '05 6.0L/4L80E with all the accessories, sensors, harness, fusebox and computer for $4k, it doesn't take that much work to get that thing to 500hp.

he's talking about getting a TPI 3rd gen which means aftermarket computer, already mentioned F.A.S.T., that along with a good efi intake is going to eat up a majority of the price margin. sure it may still be cheaper but not by much.