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-   -   TBI 454 Build - 50 State Legal (https://67-72chevytrucks.com/vboard/showthread.php?t=537968)

JCampbell 08-11-2012 02:32 PM

TBI 454 Build - 50 State Legal
 
Looking at building a TBI 454 for my C30 crew cab dually. I don't want a hot rod, but I do want to up the HP/torque numbers a bit for towing and general 1-ton abuse. However, I want something that will yield reliability and longevity. I was browsing over at TBIchips.com and I ran across this build:

http://tbichips.com/Jim454.htm

Seems like a solid platform, but I'm curious about the heads on this build. Specifically, will I still be able to run 87 octane fuel? Also, anyone have any educated guesses on what the MPGs might look like on such a combination? I was getting somewhere in the neighborhood of 10.5-11 MPG on the stock set up w/ a TH400, 4.11's and 225/75/16 tires. Not looking for Prius-like numbers, but certainly don't want to decrease from the stock MPG numbers.

INSIDIOUS '86 08-11-2012 03:42 PM

Re: TBI 454 Build - 50 State Legal
 
No need for aftermarket heads. Peanut ports support that same hp and do real good with minor bowl blending. But it looks like a solid build for sure. Add an electric fan and little things here and there and you will come out ahead on mpg and power for less if need be
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KQQL IT 08-11-2012 04:54 PM

Re: TBI 454 Build - 50 State Legal
 
Put a crank in it. 496 cid
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JCampbell 08-11-2012 11:40 PM

Re: TBI 454 Build - 50 State Legal
 
Gee, thanks for that insightful bit of info that had nothing to do with my original post.

JCampbell 08-11-2012 11:48 PM

Re: TBI 454 Build - 50 State Legal
 
Quote:

Originally Posted by INSIDIOUS '86 (Post 5534049)
No need for aftermarket heads. Peanut ports support that same hp and do real good with minor bowl blending.

I've always been told the peanut ports, while not horrible, are the chink in the HP armor, so to speak.

JCampbell 08-11-2012 11:53 PM

Re: TBI 454 Build - 50 State Legal
 
From this thread: http://67-72chevytrucks.com/vboard/s...d.php?t=388216

Quote:

Originally Posted by SCOTI (Post 5303244)
For what it's worth.... I researched the flow data on the PP heads that came w/the 7.4l in my dually & they were similar to AFR's 190cc sbc 23° street heads up to around .500 lift. From my perspective, that type of flow should yield good torque from a larger displacement engine/pkg as long as the valvetrain is sized accordingly.

I hear many say the PP's are junk but I believe that's only true for a higher compression larger cam set-up that exceeds the heads ability to flow. Anything under the 4K rpm ceiling & they'll work just fine. They may not be as good as some 781 ovals @ the more agressive end of things, but they'll still work up to their limitations.


Interesting...

KQQL IT 08-11-2012 11:55 PM

Re: TBI 454 Build - 50 State Legal
 
Sorry but tbi big blocks are not known for mileage or making power.
We had an 89 1ton 454 4spd. Got 6/9mpg and cooked exhaust manifolds
My vortec gets10-12 if the wife drives. 4l80 4:10 and a 31" tire.
In my 6000lb crewcab.
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INSIDIOUS '86 08-12-2012 01:13 AM

Re: TBI 454 Build - 50 State Legal
 
Most aftermarket heads even hardly give a flow improvement over the stock castings. If your worried about flow you can go to ovals but low end will take a minor hit

Proof peanut ports do fine-
http://www.carcraft.com/techarticles...d/viewall.html
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JCampbell 08-12-2012 01:59 AM

Re: TBI 454 Build - 50 State Legal
 
Yeah, I've been doing some reading tonight. I think you're right.

Bowl blending: got any links?

JCampbell 08-12-2012 02:01 AM

Re: TBI 454 Build - 50 State Legal
 
I can't get that link to load, BTW.

huahuamick 08-12-2012 05:22 AM

Re: TBI 454 Build - 50 State Legal
 
Good thread, I always like them.
http://www.couponsavings.info/rec/smile.jpg
http://www.couponsavings.info/for/smile.jpg

rfmaster 08-12-2012 12:00 PM

Re: TBI 454 Build - 50 State Legal
 
JC

JC the PP BBC heads are good up to about 4k RPM. These heads were designed with high velocity intake runners to fill cylinders from intake efficiently at low engine RPM's. This is why they do not well with higher lift - longer duration cams or at higher RPM's - the airflow stalls. Lunati cam 60210LK is nice improvement over a stock bump-stick, but it is mild by BBC standards and has 112 LSA needed to keep idle vacuum levels reasonable. For your build where you are after low RPM torque a simple bowl porting will improve airflow, but do not expect a 1/4 mile screamer. Bowl porting can not be done on a regular production line due to cost involved.
As long as you keep CR under 9.25:1 and decent quench engine should be able to tolerate 87 crap gas that we have here (E10). The KS can take care of knock if and when it happens. A custom tune should be done on any combo since no two engine - trany combinations are identical. You can start with a baseline (from TBI chips) and later tweak VE and SA curves to get additional performance. Use of TH400 will keep engine RPM relatively high at highway speeds - the 4L80E or manual gear box would be a better choice for highway MPG. IMHO, good enough for another 1.5 to 2 MPG over THM400.

//RF

Firebirdjones 08-12-2012 01:10 PM

Re: TBI 454 Build - 50 State Legal
 
Lingenfelter showed the peanut port heads were decent performers back in the early 80's. With minor bowl and port work he made 600 HP and TQ on a 496 build back then for cheap.

Not many details on that build posted above other than cam specs and Edlebrock heads. Cam was ground with 6 degrees of advance ;)

Ideally if you are looking for a complete rebuild of the engine, I'd do a 4.250 roatating assembly like KQQL IT mentioned. Cheap TQ increase.

I looked at the same thing for mine, but ultimately decided to do a 502 crate motor, 400 turbo, 3.73 gears, 29" tire. I get 11-12 mpg around town and 14 mpg highway.
Mine is a peanut port 502 with a very tiny roller cam (.480 lift). I installed a simple performer intake and stock quadrajet (tweaked) and small tube (1 3/4") headers and it dyno'd at 377 hp and 540 ft lbs. tq. It peaked at 5300 rpm which was higher than I had expected but what I really liked about it was the extremely flat torque curve. Over 500 ft lbs. from 2700 rpms all the way up to 4500 rpms.

It pulls like a deisel and lays rubber for a block :lol:

I'm doing a gear vendor for a little more MPG highway and it's gear split ability for around town towing. It should get me another 2-3 mpg easily.

JCampbell 08-12-2012 01:43 PM

Re: TBI 454 Build - 50 State Legal
 
Great info, thanks.

As far as cams go, is there a necessity to a roller conversion cam versus a "drop in" cam of the same (or close) grinds? That Lunati is a $650 investment...not really looking to spend that kind of money unless a necessity. What about something like a Summit sum-1300? Supposedly a pretty torquey cam for heavy trucks/towing.

http://tbichips.com/454ss.htm

RF - I'm *really* reconsidering the 4L80e option.

Firebirdjones 08-12-2012 01:51 PM

Re: TBI 454 Build - 50 State Legal
 
Certainly nothing wrong with a flat tappet cam if that's what is in your budget.

I myself have become a roller cam junky over the last 15 years or so just for the advantages they offer and ease of break in. I agree, it's pricey. A retrofit roller cam swap in the older engines is usually around $1000.

rfmaster 08-12-2012 01:58 PM

Re: TBI 454 Build - 50 State Legal
 
Quote:

Originally Posted by Firebirdjones (Post 5535419)
Lingenfelter showed the peanut port heads were decent performers back in the early 80's. With minor bowl and port work he made 600 HP and TQ on a 496 build back then for cheap.

JC the only problem with high HP numbers that a modified PP BBC heads can deliver, is the fact that eventually there is going to be a fuel delivery limitation imposed by a pair of TBI injectors. When you go through the calculation a pair of BBC injectors (80 lb-hr) can potentially support 340 HP at 13 to 15 PSI fuel pressure. To support 400+ HP a bump in fuel pressure to about 20 to 25 PSI will be required. A custom tune (or DIY tuning) will have to be performed. A large displacement BBC mill will run out of fuel very quickly. Since your goal is 50 state legal (yea, both us live in eco-stupid state of Kalifornia) a 454 displacement will be your limit unless you plan to build a stroker and keep it below 4000 RPM.

//RF

Firebirdjones 08-12-2012 02:01 PM

Re: TBI 454 Build - 50 State Legal
 
Quote:

Originally Posted by rfmaster (Post 5535488)
JC the only problem with high HP numbers that a modified PP BBC heads can deliver, is the fact that eventually there is going to be a fuel delivery limitation imposed by a pair of TBI injectors. When you go through the calculation a pair of BBC injectors (80 lb-hr) can potentially support 340 HP at 13 to 15 PSI fuel pressure. To support 400+ HP a bump in fuel pressure to about 20 to 25 PSI will be required. A custom tune (or DIY tuning) will have to be performed. A large displacement BBC mill will run out of fuel very quickly. Since your goal is 50 state legal (yea, both us live in eco-stupid state of Kalifornia) a 454 displacement will be your limit unless you plan to build a stroker and keep it below 4000 RPM.

//RF

Yes the TBI is going to be the limiting factor that chokes potential. I didn't take into account you are in Cali, I was going to recommend a FAST EFI swap for better tunability and power.

INSIDIOUS '86 08-12-2012 07:19 PM

Re: TBI 454 Build - 50 State Legal
 
Just look up demon engines 454 builds from car craft.
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JCampbell 08-16-2012 11:36 AM

Re: TBI 454 Build - 50 State Legal
 
I don't have the casting numbers on me, but my block seems to be set up for a roller cam. It has the risers cast into the valley of the bock that I assume are for the "spider" to bolt down to.

That being said, is it worth the investment to go with a roller cam on this particular build, or will a flat tappet suffice? In other words, is there a significant HP gain by going with a roller set up?

Firebirdjones 08-16-2012 11:49 AM

Re: TBI 454 Build - 50 State Legal
 
Quote:

Originally Posted by JCampbell (Post 5541930)
I don't have the casting numbers on me, but my block seems to be set up for a roller cam. It has the risers cast into the valley of the bock that I assume are for the "spider" to bolt down to.

That being said, is it worth the investment to go with a roller cam on this particular build, or will a flat tappet suffice? In other words, is there a significant HP gain by going with a roller set up?

That's really a judgement call based on your pocket book.

As far as HP, yes the roller cams will gain some HP and TQ over a similarly spec'd flat tappet. For some it's not worth the added expense, but for people like myself, I see other advantages like no real cam break in, no worries about ZDDP in the oils, less heat, less friction, and you can get fancy with much faster ramp profiles (you can only get so far with a flat tappet and small diameter lifters) and yet still keep the camshaft very mild and gain HP.
Also a similarly spec'd flat tappet cam tends to act a little more rambunctious compared to a roller of similar specs. So you gain a slight amount of drivability and vacuum with a roller of the same size.

It's just getting over that initial cost ;). Once done though, you can also change camshafts down the road and reuse the same roller lifters, where as a flat tappet requires new lifters and another break in procedure.

You'll find it's not the roller cams themselves that are all that expensive, it's the lifters that cost money. Then you'll need shorter pushrods, new valve springs etc...

rfmaster 08-16-2012 02:43 PM

Re: TBI 454 Build - 50 State Legal
 
Getting back to the harness question. Ideally I would try to find 94-95 4L80E equipped burban at a local JY and pull a complete harness, PCM and trany. However, we live in less than ideal world. The 4L80E equipped burbas are rare and almost always are ripped apart within minutes they are putout. The more plentiful 4L60E equipped trucks and burbans are very common. The 4L60E harness and PCM can be sourced very easily. As I have mentioned before the 4L60E and its bigger brother use different interface plugs. However, the connectors (at trany and at PCM) can be easily repined. Paying $250 for adapter harness between 4L60E plug and 4L80E makes my blood boil - rip off alert! The other item is re-programming of the PCM. The 16197427 PCM was used with manual, 4L60E and 4L80E transmissions the difference being a calibration EPROM. This requires some one to burn you an EPROM with 4L80E calibration or sourcing PCM from 4L80E vehicle.

The 4L60E to 4L80E is a common swap for 96 and up trucks:
http://www.fourwheeler.com/techartic...smission_swap/

//RF

JCampbell 08-16-2012 04:29 PM

Re: TBI 454 Build - 50 State Legal
 
So what is generally cheaper/easier? To go with an OEM setup and source the parts from Napa (or equiv.) of just go with a full blown retrofit kit like that Lunati?

rfmaster 08-16-2012 05:26 PM

Re: TBI 454 Build - 50 State Legal
 
JC

I have built several flat tappet motors in the last 12 month. In the first engine (305) I installed NOS Crane cam and lifters while in the second engine (350) I went with CS1014r and HT817 lifters (its powering Beast now). In both builds I used liberal amounts of Crane super moly assembly lube to coat cam lobes and lifters. Both engines were pre-lubed and broken-in with Lucas SAE 30W #10631 and a shot of Lucas engine Break-In Oil Additive #10063 for a good measure. Resulting oil mix had high ZDDP levels. The 305 and 350 are equipped with better than stock springs - 90 to 100 psi closed and 280 to 300 PSI at max lift springs (basically Z28 rated springs). In both instances engines were fired without cats for 25 to 30 minutes while varying RPMS between 2000 and 2800!! No problems reported on 305 after 5000+ miles and on 350 the jury is still out.

If the budget is tight - go with a better grade flat tappet cam & lifters, keep valve spring pressure near or just above stock, and make sure that break in procedure is performed correctly. Once cam breaks-in, in first oil change use ZDDP additive for the first 1500 miles or so. After that use quality mineral grade oil, but look for oil with higher level ZDDP (Rotela-T). Engine should be ok.

//RF

JCampbell 08-16-2012 05:52 PM

Re: TBI 454 Build - 50 State Legal
 
Yeah, seems like flat tappet fits my budget a lot better than a retro roller.

eldogg 08-20-2012 09:06 AM

Re: TBI 454 Build - 50 State Legal
 
Mine is .030 over w/flat top pistons (70 LS6 style), balanced, Smallest Summit cam, Comp roller tip rockers, Edelbrock TBI intake, Edelbrock headers, TBI chip, Upgraded fuel pump and regulator spring, Single 3" exhaust w/ largest Magnaflow muffler. I get 11-12 mpg in town and 7-8 mpg hwy. TH400 4:10 235/85/16. It will run on 87 but it likes 89 a whole lot better. I will give the pepsi challenge to any stock diesel to about 70mph. If you have any questions about my combo PM me. There is some pics of it on here. http://queencityspeed.blogspot.com/2...lug-wires.html


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