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Budget pulling truck engine named (Tommy Boy)

Posted: Mon Jan 30, 2017 11:49 pm
by randy331
My son ran a street stock pulling truck last summer for the first time, and after he got the truck working good with his smog head 355, I loaned him one sittin in the shop that made 525 HP on it's best pull. That got him a second place finish.

So,.. in his quest for more power, but with no money, he found and bought most of a 355 SBC that had been in a drag car. The 355 had ran a sub 10 sec 1/4 mile pass in good air, in a 2900 lb car, so it made decent power for what it is.

He got,
ported victor, JR.
Ported 034 bowties with 2.05-1.6 valves needed guides, but took them up for knurling, and they are "better" :D
Some Scat 6" rods
Some Ross dome pistons DR-390 is on them,.. pins/locks. Not sure but comp be 13.5-1 ish area looks like.
A Herbert roller cam I measured to be 265-277-108 .416" lobes
Some roller lifters not sure what brand
No crank, but found a good Cola 3.48" stroke, that may work out for a decent price
Some rockers maybe an oil pump

I went through stuff in the shop and found 8 Comp cam 954 springs and 8 Comp cams 26089 springs, and Comp cams tool steel retainers for both. Had 8 locators for the 954s springs ,but had to buy a set for the 26089. Some used keepers.
I had an adjustable timing set up for it so we'll be able to change cam timing easy.

Dug out a solid roller sittin in the shop of unknown origin that measures 272-273-107 .415" lobes that's 2 deg faster from .020"-.050". Don't remember where this one came from, but could try it???

Things are cleaned and read to go together, so hoping to get to the dyno in the next month.
Probably be a 2 day dyno session
Got a carb back from carb shop I need to test on something, so there'll be 2-3 carbs on it.
May try both cams. Got a full set of 1.5 and 1.6 rockers we can try, and 8 1.65 rockers.
Got a ported 10051103 bowtie sittin here we could try if it fits decent.
Got a 300-25 here to, un ported so far. Could try it.

Be any difference in those cams?
Power level?
Thinking he needs to come out high and let the sled pull in back into the power curve?
Looks like that's what the better trucks are doing??,.. but I've never pulled.

Anyway,... had a little time, so thought I'd share the Tommy Boy budget build. :)

The engine is named Tommy Boy for a couple reasons.

Randy

Re: Budget pulling truck engine named (Tommy Boy)

Posted: Tue Jan 31, 2017 12:29 am
by wyrmrider
I'd cam doc those cams
the Herbert grind may be from - well idk how far back- most likely easy on springs and valve train unless jerky
any number on it back in the day we did not have good springs or roller rockers so cams had to be not as quick intensity wise

Re: Budget pulling truck engine named (Tommy Boy)

Posted: Tue Jan 31, 2017 9:11 am
by CGT
Seems to be several recent threads on making the best out of piles of old are used parts. I think its cool. I think there are several pulling truck guys on here....PFC1 is sharp and a Missouri guy, maybe he will chime in.

I suppose "Tommy Boy" will be heading out my way for dynoz and beerz. Looking forward to it if so. Have you considered trying some valve job testing on Tommy? A camshaft that isn't just "laying around" You don't have to get all the testing done in one day?

I don't have much pulling truck experience but once the basic rpm range has been established, focus on optimizing that on the dyno? Maybe some reverse pulls?

I would think the two cams you have would run similiarly.

Re: Budget pulling truck engine named (Tommy Boy)

Posted: Tue Jan 31, 2017 11:55 am
by randy331
CGT wrote: I suppose "Tommy Boy" will be heading out my way for dynoz and beerz.
Yes, it will be heading out to your neighborhood for dyno, and beerz could be included. :D
How about steaks ? They seem to help with dyno results evaluation, and with beerz.

Got a 3 rd cam volunteered for testing in Tommy Boy. It's a Comp Cam 248-258-109 RT intake NC ex lobes.
Thinkin it would be a better test. I'd like to see a bigger change than the one I got sittin here.
It may fatten up the whole power curve for a small loss up top, which could be a plus when he misses the truck set up on a good hookin track.

Valve job,.. it's whatever the heads had when they got here, with just a quick lap to make sure the knurl didn't move stem centerline.
They could use a valve job. Probably go 50-55 when that happens.

Randy

Re: Budget pulling truck engine named (Tommy Boy)

Posted: Tue Jan 31, 2017 1:10 pm
by wyrmrider
I randy- I would not just do a lap after a knurl
I would be surprised if they did not move and all the lap will do is tell you that you have runout
just as quick to throw them in the SERDI and cut shat 3-5 angles

Re: Budget pulling truck engine named (Tommy Boy)

Posted: Tue Jan 31, 2017 6:07 pm
by KnightEngines
Can you fit K-lines?
From what I've seen in the past knurling is temporary, if the heads are 1/2 decent some K-lines & a fresh valve job would be worth the effort.

An idea, that may not suit the budget, but for a puller wouldn't more cubes be a nice thing to have? - I reckon if you look at comp height on the pistons closely you may find that you can use them with a 3.75" crank & 5.85" rods.
That does mean you'd need a new crank (scat cast would be fine methinks) & rods.

Should be a mean SOB for the outlay, gotta love a spare parts stomper.

Re: Budget pulling truck engine named (Tommy Boy)

Posted: Tue Jan 31, 2017 7:30 pm
by zums
Well Farley was a fat alcoholic drug addict, but funny as hell, so whats the reference?

Re: Budget pulling truck engine named (Tommy Boy)

Posted: Tue Jan 31, 2017 7:52 pm
by Carnut1
I like the iron bowtie head but it is kind of lame stock. They really could use some of your porting talent. Thanks, Charlie

Re: Budget pulling truck engine named (Tommy Boy)

Posted: Tue Jan 31, 2017 8:16 pm
by randy331
zums wrote:Well Farley was a fat alcoholic drug addict, but funny as hell, so whats the reference?
Tommy Boy seemed kinda incompetent, but "pulled through big time" in the end.
Kinda what were hoping for with this Tommy Boy. :D

And most of the parts were purchased from a guy named Tommy.

Engines run better with thoughtful names. Makes them feel like part of the family. :)

Randy

Re: Budget pulling truck engine named (Tommy Boy)

Posted: Tue Jan 31, 2017 9:08 pm
by zums
gotcha

Re: Budget pulling truck engine named (Tommy Boy)

Posted: Tue Jan 31, 2017 9:13 pm
by cgarb
Some of my engines have curse words for names...lol. A 350 Buick race engine I remember that pushed me to my breaking point. Threw in the towel on that one and bought a sbc.

Re: Budget pulling truck engine named (Tommy Boy)

Posted: Wed Feb 01, 2017 5:03 am
by paulzig
Bet you'll surprise us again like you did with that pseudo racing 383 Randy ...

Re: Budget pulling truck engine named (Tommy Boy)

Posted: Wed Feb 01, 2017 9:49 am
by steve316
Used parts are sorted out; if they haven't been pushed to their limits they are a great bang for your buck. :mrgreen:

Re: Budget pulling truck engine named (Tommy Boy)

Posted: Wed Feb 01, 2017 1:24 pm
by rebelrouser
I have built a few truck pulling engines, and usually only the guys that win understand proper wheel speed and a broad torque curve. The losers all say they just need more engine, when they are wasting what they have many times by over revving or lugging the combination they have.

Re: Budget pulling truck engine named (Tommy Boy)

Posted: Wed Feb 01, 2017 5:13 pm
by randy331
Wheel speed is a big part of it, but the better trucks do seem to over rev them some.
I mean if you hook to a sled with a given set-up and the track is looser than thought, and the engine will rev on to 8000 but makes peak HP at 7000 it will still have more tire speed at 8000.

Randy