HESCO head and looking to build 4.6L - Need opinions

[SCRMBLDXJ]

Hello All,

I have a HESCO head that's been in storage for years; it was on an engine that failed for some cam related issue and was pulled for a LS swap ~15 years ago. (I will have it pressure tested and checked, but to my knowledge, it should have many hrs of life left in it.) I also have '95 4.0L & '98 4.0L engines on stands that both ran with a slight rocker tick or piston slap until they warmed up. I plan to buy a Clegg kit for this project. This will be my first stroker... I want to learn about strokers through this HESCO head 4.6L project.

This motor will be going in my '98 XJ daily driver, w an AW4 & NP231. I plan to build another stroker in the next 5 yrs for a '83 CJ-8 project that I'm mildly upgrading/modifying (why I want a Jeep I-6 for it). In the past, I've built two SBCs (355 & 383) ~25 yrs ago and I grew up around cars. My father was a dirt short-track stock car crew chief and I had a considerable amount of wrench time in my teens and early 20s, then I finished college, joined the Army, got deployed a few times, got married, house, family and etc. I've owned a Jeep since I was 17 and every vehicle we drive is a Jeep. I'm not specifically a Jeep fanatic, but I have knowledge of how to work on any part of a CJ, XJ, TJ or JK, multiples of spare parts and we love the capabilities & experience of driving a Jeep... so that's all we own.

The goal for this project is (1.) reliability/longevity, (2.) learning about the nuances of Jeep stroker motors and (3.) gaining some HP/torque over a 4.0L. I'm planning to run high octane pump gas, but I want to be able to limp it home on 87 octane if needed (when that's all that can be found). I'm leaning toward buying a Clegg Stage 2 kit for the lower end. I have a '99 XJ intake, 62mm TB, a spare wire harness & ECM. I also have '86 258 crank, but I'm leaning toward just getting a Clegg kit for this engine and using the 258 crank in the next stroker project.

I'm looking for recommendations for a HESCO head 4.6 build to fit the parameters above...

Would anyone recommend a Clegg kit? Which one?

Are there better options going all parts separate?

Recommended cam selections?

Thanks in advance for your help and recommendations!

V/R,
Scott

[Cheromaniac]

The Clegg kit looks good but I'd shave 0.010" from the block deck to bump the lowish 9.3 compression up a couple of tenths.
If your Hesco head is already assembled with upgraded valve springs, you could go for the Comp cams 68-301-5 camshaft. The shortish duration and higher valve lift should deliver plenty of torque.

[mpgMike]

A note on block selection; the '96 - '98 blocks are considered the best ones. They have the main girdle reinforcement plate, for one. When using one in a stroker, you will have to shim this plate away from the block slightly to clear the connecting rods. Not too much, as you won't be able to get the oil pan on. I used a '96 block for my 4.6 in my '95 ZJ.

cEng.png

[SCRMBLDXJ]

Gentlemen, thanks very much for the information!

Here are some updates, and more questions…

I went through my parts stash, which has become a little crazy after 25+ yrs of collecting… I found that I have 3x complete 91-95 XJ engines, and I found a 258 crank that looks like it could be reground/polished (casting #3235477; it was stored upright). I also found a Cloyes 9-3127 timing set, a late model 4.0L main bearing girdle and a slightly odd Comp cam (more below).

I know the 96-98 blocks had some reinforcement webbing cast in and the bottom end girdle, but I have more early blocks (casting #53008405), so I’m thinking of using a 91-95 block for this build. It seems the main girdle will bolt on to the older style mains. I’m planning to use ARP main studs (PN ARP 146-5401) and an ARP girdle spacer kit, and then mount the girdle to the older design block. Will this work? Is it worth the time/trouble?

The Comp Cams is PN 163-000-5, it came from a Summit outlet store (for $100). This cam appears to be a custom grind…

CompCams 163-0005-5.jpg

It seems to be ground very close to 68-301-5, but with slightly less valve lift. And, it seems to have late model style nomenclature but has the older style cam button/mechanism. Do these custom grinds from Comp Cams have a good/bad reputation? Potential issues?

Cam Bearing Question: Comparing ACL cam bearings (PN- 4C549S) or Dura Bond cam bearings (PN- N7B); which is better in anyone’s experience? ACL are recommended/used by Newcomer and Clegg’s recommended Dura Bond.

Are Johnson/Hylift lifters worth buying, rather than using Comp Cams lifters? Do Johnson lifters make that much difference in durability or power in anyone’s experience?

I’m planning to use factory 4.0L rods that were reconditioned by the machine shop. I’m going to have the shop balance the reground 3235477 crank and rotating assembly. I was planning to buy a Clegg kit, but I’m not going now that I found a 258 crank. However, I’m thinking of using the Keith Black hypereutectic dish pistons [-21cc] (PN - KB438C), but Summit seems to be sold old of these and only Clegg’s seem to have them for $120 more than Summit was selling them for. Is there a similar hypereutectic piston that has an estimated compression ratio of 9.3:1?

One final question (for now)? Can a HESCO adjustable fuel pressure regulator, w 24lbs injectors be used with the factory ‘98XJ computer to tune this 4.6L or should I start looking for other things to tune this right?

[Cheromaniac]

1. The '91-'95 blocks will do fine for a stroker build without the main cap girdle. If you can find a set of main cap studs with the matching nuts, by all means use it with the appropriate thickness shims.

2. The camshaft and the 258 crank you have will also do fine for the stroker build. However you'll need to insert a 10mm thick keyed spacer in front of the harmonic balancer. If you have an old harmonic balancer, cut off the rearmost 10mm portion and use that as your spacer.

3. You could reach out to Russ Pottenger for a set of pistons.

4. The '96-'04 4.0L Jeeps use a 49psi fuel system so as long as the Hesco adjustable regulator has that range of adjustment, you can use it.

[Russ Pottenger]

More than happy to help you out with a set of pistons to a rotating assembly along with camshaft recommendations.

Feel free to contact me directly at:
Russ Pottenger
Bishop-Buehl Racing Engines
531 N. Lyall Avenue
West Covina, California 91790
Work (626) 967-1000
Cell (626) 673-2203
Email: [email protected]